WorldWideScience

Sample records for high-dose rate conformal

  1. High-dose-rate Three-dimensional Conformal Radiotherapy Combined with Active Breathing Control for Stereotactic Body Radiotherapy of Early-stage Non-small-cell Lung Cancer.

    Science.gov (United States)

    Wang, Ruozheng; Yin, Yong; Qin, Yonghui; Yu, Jinming

    2015-12-01

    The purpose of this study was to evaluate the feasibility and benefits of using high-dose-rate three-dimensional conformal radiotherapy (3D-CRT) combined with active breathing control (ABC) for stereotactic body radiotherapy (SBRT) of patients with early-stage non-small-cell lung cancer (NSCLC). Eight patients with early-stage NSCLC underwent CT scans under standard free-breathing (FB) and moderately deep inspiration breath-hold (mDIBH) with ABC. Two high-dose-rate 3D-CRT plans (1000 Mu/min) were designed based on the CT scans with FB and mDIBH. The maximal dose (D1%), minimal dose (D99%), conformity index (CI), and homogeneity index (HI) of the planning target volume (PTV), and dose-volume indices of the organs at risk between each plan were compared. The mean PTV volume decreased from 158.04 cm(3) with FB to 76.90 cm(3) with mDIBH (p < 0.05). When mDIBH was used, increases in the affected lung volume (by 47%), contralateral lung volume (by 55%), and total lung volume (by 50%) were observed compared to FB (p < 0.05). The V5-V40 of the affected lung (Vx represented the percentage volume of organs receiving at least the x Gy), V5-V40 and the mean dose for the total lung, V5-V40 and mean dose of the chest wall, and the maximum dose of the spinal cord were less for mDIBH than FB (p < 0.05). There were no significant differences in CI, HI, D1%, or D99% for the PTV between the plans. In conclusion, high-dose-rate 3D-CRT combined with ABC reduced the radiation dose to the lungs and chest wall without affecting the dose distribution in SBRT of early-stage NSCLC patients. © The Author(s) 2014.

  2. A novel conformal superficial high-dose-rate brachytherapy device for the treatment of nonmelanoma skin cancer and keloids.

    Science.gov (United States)

    Ferreira, Clara; Johnson, Daniel; Rasmussen, Karl; Leinweber, Clinton; Ahmad, Salahuddin; Jung, Jae Won

    To develop a novel conformal superficial brachytherapy (CSBT) device as a treatment option for the patient-specific radiation therapy of conditions including superficial lesions, postsurgical positive margins, Dupuytren's contractures, keloid scars, and complex anatomic sites (eyelids, nose, ears, etc.). A preliminary CSBT device prototype was designed, built, and tested using readily available radioactive seeds. Iodine-125 ((125)I) seeds were independently guided to the treatment surface to conform to the target. Treatment planning was performed via BrachyVision Planning System (BPS) and dose distributions measured with Gafchromic EBT3 film. Percent depth dose curves and profiles for Praseodymium-142 ((142)Pr), and Strontium-90/Yttrium-90 ((90)Sr-(90)Y) were also investigated as potential sources. Results achieved with (90)Sr-(90)Y and electron external beam radiation therapy were compared and Monte Carlo N-Particle eXtended 2.6 simulations of (142)Pr seeds were validated. BPS was able to predict clinical dose distributions for a multiple seeds matrix. Calculated and measured doses for the (125)I seed matrix were 500 cGy and 473.5 cGy at 5 mm depth, and 171.0 cGy and 201.0 cGy at 10 mm depth, respectively. Results of (90)Sr-(90)Y tests demonstrate a more conformal dose than electron EBRT (1.6 mm compared to 4.3 mm penumbra). Measured (142)Pr doses were 500 cGy at surface and 17.4 cGy at 5 mm depth. The CSBT device provides a highly conformal dose to small surface areas. Commercially available BPS can be used for treatment planning, and Monte Carlo simulation can be used for plans using beta-emitting sources and complex anatomies. Various radionuclides may be used in this device to suit prescription depths and treatment areas. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  3. 3-D conformal treatment of prostate cancer to 74 Gy vs. high-dose-rate brachytherapy boost: A cross-sectional quality-of-life survey

    Energy Technology Data Exchange (ETDEWEB)

    Vordermark, Dirk [Univ. of Wuerzburg (DE). Dept. of Radiation Oncology] (and others)

    2006-09-15

    The effects of two modalities of dose-escalated radiotherapy on health-related quality of life (HRQOL) were compared. Forty-one consecutive patients were treated with a 3-D conformal (3-DC) boost to 74 Gy, and 43 with high-dose rate (HDR) brachytherapy boost (2x9 Gy), following 3-D conformal treatment to 46 Gy. Median age was 70 years in both groups, median initial PSA was 7.9 {mu}g/l in 3-DC boost patients and 8.1 {mu}g/l in HDR boost patients. Stage was 7 in 52% and 47%, respectively. HRQOL was assessed cross-sectionally using EORTC QLQ-C30 and organ-specific PR25 modules 3-32 (median 19) and 4-25 (median 14) months after treatment, respectively. Questionnaires were completed by 93% and 97% of patients, respectively. Diarrhea and insomnia scores were significantly increased in both groups. In the PR25 module, scores of 3-DC boost and HDR boost patients for urinary, bowel and treatment-related symptoms were similar. Among responders, 34% of 3-DC boost patients and 86% of HDR boost patients had severe erectile problems. Dose escalation in prostate cancer by either 3-DC boost to 74 Gy or HDR brachytherapy boost appears to result in similar HRQOL profiles.

  4. Concomitant chemoradiotherapy with high dose rate brachytherapy ...

    African Journals Online (AJOL)

    Purpose: This study aims to report the incidence of treatment-induced acute toxicities, local control and survival of patients with cervix cancer treated by external beam radiotherapy (EBR) and high-dose-rate (HDR) brachytherapy concomitant with weekly Cisplatin chemotherapy. Methods: Forty patients with FIGO Stages IB2 ...

  5. High dose rate brachytherapy for oral cancer

    Science.gov (United States)

    YamazakI, Hideya; Yoshida, Ken; Yoshioka, Yasuo; Shimizutani, Kimishige; Furukawa, Souhei; Koizumi, Masahiko; Ogawa, Kazuhiko

    2013-01-01

    Brachytherapy results in better dose distribution compared with other treatments because of steep dose reduction in the surrounding normal tissues. Excellent local control rates and acceptable side effects have been demonstrated with brachytherapy as a sole treatment modality, a postoperative method, and a method of reirradiation. Low-dose-rate (LDR) brachytherapy has been employed worldwide for its superior outcome. With the advent of technology, high-dose-rate (HDR) brachytherapy has enabled health care providers to avoid radiation exposure. This therapy has been used for treating many types of cancer such as gynecological cancer, breast cancer, and prostate cancer. However, LDR and pulsed-dose-rate interstitial brachytherapies have been mainstays for head and neck cancer. HDR brachytherapy has not become widely used in the radiotherapy community for treating head and neck cancer because of lack of experience and biological concerns. On the other hand, because HDR brachytherapy is less time-consuming, treatment can occasionally be administered on an outpatient basis. For the convenience and safety of patients and medical staff, HDR brachytherapy should be explored. To enhance the role of this therapy in treatment of head and neck lesions, we have reviewed its outcomes with oral cancer, including Phase I/II to Phase III studies, evaluating this technique in terms of safety and efficacy. In particular, our studies have shown that superficial tumors can be treated using a non-invasive mold technique on an outpatient basis without adverse reactions. The next generation of image-guided brachytherapy using HDR has been discussed. In conclusion, although concrete evidence is yet to be produced with a sophisticated study in a reproducible manner, HDR brachytherapy remains an important option for treatment of oral cancer. PMID:23179377

  6. Transit dose calculation in high dose rate brachytherapy (HDR ...

    African Journals Online (AJOL)

    Transit doses around a high dose rate 192Ir brachytherapy source were calculated using Sievert Integral at positions where the moving source was located exactly between two adjacent dwell positions. The correspond-ing transit dose rates were obtained by using energy absorption coefficients. Discrete step sizes of 0.25 ...

  7. Dose determination in high dose-rate brachytherapy.

    Science.gov (United States)

    Houdek, P V; Schwade, J G; Wu, X; Pisciotta, V; Fiedler, J A; Serago, C F; Markoe, A M; Abitbol, A A; Lewin, A A; Braunschweiger, P G

    1992-01-01

    Although high dose-rate brachytherapy with a single, rapidly moving radiation source is becoming a common treatment modality, a suitable formalism for determination of the dose delivered by a moving radiation source has not yet been developed. At present, brachytherapy software simulates high dose-rate treatments using only a series of stationary sources, and consequently fails to account for the dose component delivered while the source is in motion. We now describe a practical model for determination of the true, total dose administered. The algorithm calculates both the dose delivered while the source is in motion within and outside of the implanted volume (dynamic component), and the dose delivered while the source is stationary at a series of fixed dwell points. It is shown that the dynamic dose element cannot be ignored because it always increases the dose at the prescription points and, in addition, distorts the dose distribution within and outside of the irradiated volume. Failure to account for the dynamic dose component results in dosimetric errors that range from significant (> 10%) to negligible (source activity, and source speed as defined by the implant geometry.

  8. Comparison of acute and subacute genitourinary and gastrointestinal adverse events of radiotherapy for prostate cancer using intensity-modulated radiation therapy, three-dimensional conformal radiation therapy, permanent implant brachytherapy and high-dose-rate brachytherapy

    NARCIS (Netherlands)

    Morimoto, Masahiro; Yoshioka, Yasuo; Konishi, Koji; Isohashi, Fumiaki; Takahashi, Yutaka; Ogata, Toshiyuki; Koizumi, Masahiko; Teshima, Teruki; Bijl, Henk P; van der Schaaf, Arjen; Langendijk, Johannes A; Ogawa, Kazuhiko

    2014-01-01

    AIMS AND BACKGROUND: To examine acute and subacute urinary and rectal toxicity in patients with localized prostate cancer monotherapeutically treated with the following four radiotherapeutic techniques: intensity-modulated radiation therapy, three-dimensional conformal radiation therapy,

  9. Interstitial high-dose-rate brachytherapy in eyelid cancer.

    Science.gov (United States)

    Mareco, Virgínia; Bujor, Laurentiu; Abrunhosa-Branquinho, André N; Ferreira, Miguel Reis; Ribeiro, Tiago; Vasconcelos, Ana Luisa; Ferreira, Cidalina Reis; Jorge, Marília

    2015-01-01

    To report the experience and the outcomes of interstitial high-dose-rate (HDR) brachytherapy (BT) of eyelid skin cancer at the Department of Radiotherapy of Hospital de Santa Maria in Lisbon. Seventeen patients (pts; mean age, 73.75 years) who underwent eyelid interstitial HDR BT with an (192)Ir source between January 2011 and February 2013 were analyzed. Lesions were basal (94%) and squamous (6%) cell carcinomas, on lower (88%) or upper (6%) eyelids, and on inner canthus (6%). T-stage was Tis (6%), T1 (46%), T2 (36%), and T3a (12%). The purpose of BT was radical (12%), adjuvant to surgery (71%), or salvage after surgery (18%). The BT implant and treatment planning were based on the Stepping Source Dosimetry System. The median total dose was 42.75 Gy (range, 32-50 Gy), with a median of 10 fractions (range, 9-11 fractions), twice daily, 6 h apart. The median V100 was 2.38 cm(3) (range, 0.83-5.59 cm(3)), and the median V150 was 1.05 cm(3) (range, 0.24-3.12 cm(3)). At a median followup of 40 months (range, 7-43 months), the local control was 94.1%. There was one local recurrence and one non-related death. The BT was well tolerated. Madarosis was the most common late effect (65% of pts) and was related with higher values of V100 (p = 0.027). Cosmetic outcomes were good and excellent in 70% of pts. Interstitial HDR BT is a feasible and safe technique for eyelid skin cancers, with good local control. Recurrent lesions and higher volumes receiving the prescribed dose were associated with worse outcomes. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  10. Use of ultrasound in image-guided high-dose-rate brachytherapy: enumerations and arguments

    Science.gov (United States)

    Kataria, Tejinder; Gupta, Deepak; Goyal, Shikha; Bisht, Shyam Singh; Basu, Trinanjan; Abhishek, Ashu

    2017-01-01

    Inherently, brachytherapy is the most conformal radiotherapeutic technique. As an aid to brachytherapy, ultrasonography (USG) serves as a portable, inexpensive, and simple to use method allowing for accurate, reproducible, and adaptive treatments. Some newer brachytherapy planning systems have incorporated USG as the sole imaging modality. Ultrasonography has been successfully used to place applicator and dose planning for prostate, cervix, and anal canal cancers. It can guide placement of brachytherapy catheters for all other sites like breast, skin, and head and neck cancers. Traditional USG has a few limitations, but recent advances such as 3-dimensional (3D) USG and contrast USG have enhanced its potential as a dependable guide in high-dose-rate image-guided brachytherapy (HDR-IGBT). The authors in this review have attempted to enumerate various aspects of USG in brachytherapy, highlighting its use across various sites. PMID:28533803

  11. Use of ultrasound in image-guided high-dose-rate brachytherapy: enumerations and arguments

    Directory of Open Access Journals (Sweden)

    Susovan Banerjee

    2017-04-01

    Full Text Available Inherently, brachytherapy is the most conformal radiotherapeutic technique. As an aid to brachytherapy, ultrasonography (USG serves as a portable, inexpensive, and simple to use method allowing for accurate, reproducible, and adaptive treatments. Some newer brachytherapy planning systems have incorporated USG as the sole imaging modality. Ultrasonography has been successfully used to place applicator and dose planning for prostate, cervix, and anal canal cancers. It can guide placement of brachytherapy catheters for all other sites like breast, skin, and head and neck cancers. Traditional USG has a few limitations, but recent advances such as 3-dimensional (3D USG and contrast USG have enhanced its potential as a dependable guide in high-dose-rate image-guided brachytherapy (HDR-IGBT. The authors in this review have attempted to enumerate various aspects of USG in brachytherapy, highlighting its use across various sites.

  12. High-Dose Conformal Radiotherapy Reduces Prostate Cancer-Specific Mortality: Results of a Meta-analysis

    Energy Technology Data Exchange (ETDEWEB)

    Viani, Gustavo Arruda, E-mail: gusviani@gmail.com [Department of Radiation Oncology, Marilia Medical School, Marilia, Sao Paulo (Brazil); Godoi Bernardes da Silva, Lucas; Stefano, Eduardo Jose [Department of Radiation Oncology, Marilia Medical School, Marilia, Sao Paulo (Brazil)

    2012-08-01

    Purpose: To determine in a meta-analysis whether prostate cancer-specific mortality (PCSM), biochemical or clinical failure (BCF), and overall mortality (OM) in men with localized prostate cancer treated with conformal high-dose radiotherapy (HDRT) are better than those in men treated with conventional-dose radiotherapy (CDRT). Methods and Materials: The MEDLINE, Embase, CANCERLIT, and Cochrane Library databases, as well as the proceedings of annual meetings, were systematically searched to identify randomized, controlled studies comparing conformal HDRT with CDRT for localized prostate cancer. Results: Five randomized, controlled trials (2508 patients) that met the study criteria were identified. Pooled results from these randomized, controlled trials showed a significant reduction in the incidence of PCSM and BCF rates at 5 years in patients treated with HDRT (p = 0.04 and p < 0.0001, respectively), with an absolute risk reduction (ARR) of PCSM and BCF at 5 years of 1.7% and 12.6%, respectively. Two trials evaluated PCSM with 10 years of follow up. The pooled results from these trials showed a statistical benefit for HDRT in terms of PCSM (p = 0.03). In the subgroup analysis, trials that used androgen deprivation therapy (ADT) showed an ARR for BCF of 12.9% (number needed to treat = 7.7, p < 0.00001), whereas trials without ADT had an ARR of 13.6% (number needed to treat = 7, p < 0.00001). There was no difference in the OM rate at 5 and 10 years (p = 0.99 and p = 0.11, respectively) between the groups receiving HDRT and CDRT. Conclusions: This meta-analysis is the first study to show that HDRT is superior to CDRT in preventing disease progression and prostate cancer-specific death in trials that used conformational technique to increase the total dose. Despite the limitations of our study in evaluating the role of ADT and HDRT, our data show no benefit for HDRT arms in terms of BCF in trials with or without ADT.

  13. High dose rate prostate brachytherapy: an overview of the rationale, experience and emerging applications in the treatment of prostate cancer

    Science.gov (United States)

    Challapalli, A; Jones, E; Harvey, C; Hellawell, G O; Mangar, S A

    2012-01-01

    The technological advances in real-time ultrasound image guidance for high dose rate (HDR) prostate brachytherapy places this treatment modality at the forefront of innovation in radiotherapy. This review article will explore the rationale for HDR brachytherapy as a highly conformal method of dose delivery and safe dose escalation to the prostate, in addition to the particular radiobiological advantages it has over low dose rate and external beam radiotherapy. The encouraging outcome data and favourable toxicity profile will be discussed before looking at emerging applications for the future and how this procedure will feature alongside stereotactic radiosurgery. PMID:23118099

  14. Novel Use of the Contura for High Dose Rate Cranial Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Scanderbeg, Daniel J., E-mail: dscanderbeg@ucsd.edu [Department of Radiation Oncology, University of California at San Diego, La Jolla, CA (United States); Center for Advanced Radiotherapy Technologies, Rebecca and John Moores Comprehensive Cancer Center, University of California at San Diego, La Jolla, CA (United States); Alksne, John F. [Division of Neurological Surgery, University of California at San Diego, La Jolla, CA (United States); Lawson, Joshua D. [Department of Radiation Oncology, University of California at San Diego, La Jolla, CA (United States); Center for Advanced Radiotherapy Technologies, Rebecca and John Moores Comprehensive Cancer Center, University of California at San Diego, La Jolla, CA (United States); Murphy, Kevin T. [Department of Radiation Oncology, University of California at San Diego, La Jolla, CA (United States)

    2011-01-01

    A popular choice for treatment of recurrent gliomas was cranial brachytherapy using the GliaSite Radiation Therapy System. However, this device was taken off the market in late 2008, thus leaving a treatment void. This case study presents our experience treating a cranial lesion for the first time using a Contura multilumen, high-dose-rate (HDR) brachytherapy balloon applicator. The patient was a 47-year-old male who was diagnosed with a recurrent right frontal anaplastic oligodendroglioma. Previous radiosurgery made him a good candidate for brachytherapy. An intracavitary HDR balloon brachytherapy device (Contura) was placed in the resection cavity and treated with a single fraction of 20 Gy. The implant, treatment, and removal of the device were all completed without incident. Dosimetry of the device was excellent because the dose conformed very well to the target. V90, V100, V150, and V200 were 98.9%, 95.7%, 27.2, and 8.8 cc, respectively. This patient was treated successfully using the Contura multilumen balloon. Contura was originally designed for deployment in a postlumpectomy breast for treatment by accelerated partial breast irradiation. Being an intracavitary balloon device, its similarity to the GliaSite system makes it a viable replacement candidate. Multiple lumens in the device also make it possible to shape the dose delivered to the target, something not possible before with the GliaSite applicator.

  15. Comparable cell survival between high dose rate flattening filter free and conventional dose rate irradiation.

    Science.gov (United States)

    Verbakel, Wilko F A R; van den Berg, Jaap; Slotman, Ben J; Sminia, Peter

    2013-04-01

    Investigation of clonogenic cell survival and cell proliferation following single dose and fractionated delivery of high dose rate flattening filter free (FFF) irradiation compared to conventional dose rates. The human astrocytoma D384, glioma T98 and lung carcinoma SW1573 cell lines were irradiated using either a single dose (0-12 Gy) or a fractionated protocol of 5 daily fractions of 2 Gy (D384) or 3 Gy (SW1573). Cells were irradiated inside a phantom using fixed gantry beams of a linear accelerator. A sliding window technique created homogeneous dose distributions over the surface of the cell cultures. Irradiations using standard beams (6 MV, 600 MU/min.) and high dose rate FFF beams (10 MV, 2400 MU/min.) were compared. Cell survival was determined by clonogenic assay. In the fractionated irradiation set-up, the number of clonogenic cells was estimated by including tumor cell proliferation during the overall treatment time in the analysis. All cell lines showed equal cell survival following irradiation using either the FFF beams or conventional flattened (FF) beams. This was observed after single dose exposure (0-12 Gy) as well as after fractionated irradiation (p = 0.08 for D384 and 0.20 for SW1373 cell lines). FFF irradiation with a dose rate of 2400 MU/min and four times higher dose per pulse compared to irradiation with FF beams did not change cell survival for three human cancer cell lines up to a fraction dose of 12 Gy compared to irradiation using FF beams.

  16. Salvage high-dose-rate brachytherapy for local prostate cancer recurrence after radical radiotherapy

    Directory of Open Access Journals (Sweden)

    V. A. Solodkiy

    2016-01-01

    Full Text Available Studies salvage interstitial radiation therapy for recurrent prostate cancer, launched at the end of the XX century. In recent years, more and more attention is paid to high-dose-rate brachytherapy (HDR-BT as a method of treating local recurrence.The purpose of research – preliminary clinical results of salvage high-dose-rate brachytherapy applied in cases of suspected local recurrence or of residual tumour after radiotherapy.Preliminary findings indicate the possibility of using HDR-BT, achieving local tumor control with low genitourinary toxicity.

  17. High-dose-rate brachytherapy of rhabdomyosarcoma limited to the external auditory canal.

    Science.gov (United States)

    King, Martin T; Voros, Laszlo; Cohen, Gil'ad N; Lanning, Ryan M; Ganly, Ian; O'Suoji, Chibuzo C; Wolden, Suzanne L

    To report on the single-catheter high-dose-rate brachytherapy treatment of a 21-month-old girl child with an embryonal, botryoid-type, rhabdomyosarcoma limited to the external auditory canal (EAC). A 2.4-mm diameter catheter was inserted into the right EAC and placed against the tympanic membrane. A computed tomography simulation scan was acquired. A brachytherapy treatment plan, in which 21 Gy in seven fractions was prescribed to a 1-mm depth along the distal 2 cm of the catheter, was generated. Treatments were delivered under anesthesia without complication. A dosimetric comparison between this plan and an intensity-modulated radiation therapy (IMRT) plan was then conducted. A clinical target volume (CTV), which encompassed a 1-mm margin along the distal 2 cm of the catheter, was delineated for both plans. Given positioning uncertainty under image guidance, a planning target volume (PTV = CTV + 3-mm margin) was defined for the IMRT plan. The IMRT plan was optimized for maximal CTV coverage but subsequently normalized to the same CTV volume receiving 100% of the prescription dose (V100) of the brachytherapy plan. The IMRT plan was normalized to the brachytherapy CTV V100 of 82.0%. The PTV V100 of this plan was 34.1%. The PTV exhibited dosimetric undercoverage within the middle ear and toward the external ear. Mean cochlea doses for the IMRT and brachytherapy plans were 26.7% and 10.5% of prescription, respectively. For rhabdomyosarcomas limited to the EAC, a standard brachytherapy catheter can deliver a highly conformal radiation plan that can spare the nearby cochlea from excess radiation. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  18. Postoperative high-dose-rate brachytherapy in the prevention of keloids

    NARCIS (Netherlands)

    Veen, Ronald E.; Kal, Henk B.

    2007-01-01

    Background: The aim of this study is to show the efficiency of keloidectomy and postoperative interstitial high-dose-rate (HDR) brachytherapy in the prevention of keloids. Methods and Materials: Between 1998 and 2004, 35 patients with 54 keloids were treated postoperatively with HDR brachytherapy.

  19. Learning curve of MRI-based planning for high-dose-rate brachytherapy for prostate cancer

    DEFF Research Database (Denmark)

    Buus, Simon; Rylander, Susanne; Hokland, Steffen

    2016-01-01

    Purpose To evaluate introduction of MRI-based high-dose-rate brachytherapy (HDRBT), including procedure times, dose-volume parameters, and perioperative morbidity. Methods and Materials Study included 42 high-risk prostate cancer patients enrolled in a clinical protocol, offering external beam...

  20. An automated optimization tool for high-dose-rate (HDR) prostate brachytherapy with divergent needle pattern

    NARCIS (Netherlands)

    Borot, Maxence; Maenhout, M.; de Senneville, B. Denis; Hautvast, G.; Binnekamp, D.; Lagendijk, J. J. W.; van Vulpen, M.; Moerland, M. A.

    2015-01-01

    Focal high-dose-rate (HDR) for prostate cancer has gained increasing interest as an alternative to whole gland therapy as it may contribute to the reduction of treatment related toxicity. For focal treatment, optimal needle guidance and placement is warranted. This can be achieved under MR guidance.

  1. Computed Tomography–Planned High-Dose-Rate Brachytherapy for Treating Uterine Cervical Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Zolciak-Siwinska, Agnieszka, E-mail: agnieszka.zolciak@wp.pl [Department of Brachytherapy, The Maria Skłodowska-Curie Memorial Cancer Center and Institute of Oncology, Warsaw (Poland); Gruszczynska, Ewelina; Bijok, Michal [Department of Medical Physics, The Maria Skłodowska-Curie Memorial Cancer Center and Institute of Oncology, Warsaw (Poland); Jonska-Gmyrek, Joanna [Department of Teleradiotherapy, The Maria Skłodowska-Curie Memorial Cancer Center and Institute of Oncology, Warsaw (Poland); Dabkowski, Mateusz [Department of Brachytherapy, The Maria Skłodowska-Curie Memorial Cancer Center and Institute of Oncology, Warsaw (Poland); Staniaszek, Jagna [Department of Teleradiotherapy, The Maria Skłodowska-Curie Memorial Cancer Center and Institute of Oncology, Warsaw (Poland); Michalski, Wojciech [Department of Clinical Trials and Biostatistics, The Maria Skłodowska-Curie Memorial Cancer Center and Institute of Oncology, Warsaw (Poland); Kowalczyk, Adam; Milanowska, Katarzyna [Department of Medical Physics, The Maria Skłodowska-Curie Memorial Cancer Center and Institute of Oncology, Warsaw (Poland)

    2016-09-01

    Purpose: To evaluate the long-term results of computed tomography (CT)–planned high-dose-rate (HDR) brachytherapy (BT) for treating cervical cancer patients. Methods and Materials: CT-planned HDR BT was performed according to the adapted Group European de Curietherapie-European Society for Therapeutic Radiology and Oncology (GEC-ESTRO) recommendations in 216 consecutive patients with locally advanced cervical cancer, International Federation of Gynecology and Obstetrics (FIGO) stage IB to IVA, who were treated with conformal external beam radiation therapy and concomitant chemotherapy. We analyzed outcomes and late side effects evaluated according to the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer and Subjective, Objective, Management, Analysis evaluation scoring system and compared them with the results from a historical group. Results: The median age was 56 years (range, 32-83 years). The median follow-up time for living patients was 52 months (range 37-63 months). The 5-year cumulative incidence function for the local recurrence rate for patients with FIGO II and III was 5.5% and 20%, respectively (P=.001). The 5-year rates of overall survival (OS) and disease-free survival (DFS) were 66.4% and 58.5%, respectively. The relative risk of failure for OS and DFS for FIGO III in relation to FIGO II was 2.24 (P=.003) and 2.6 (P=.000) and for lymph node enlargement was 2.3 (P=.002) and 2 (P=.006), respectively. In 2 patients, rectovaginal fistula occurred, and in 1 patient, vesicovaginal fistula occurred without local progression. Comparison of late adverse effects in patients treated according to the GEC-ESTRO recommendations and in the historical group revealed a reduction in fistula formation of 59% and also a reduction in rectal grade 3 to 4 late toxicity of >59%. Conclusions: This is the largest report with mature data of CT-planned BT HDR for the treatment of cervical cancer with good local control and

  2. A dose verification tool for high-dose-rate interstitial brachytherapy treatment planning in accelerated partial breast irradiation.

    Science.gov (United States)

    Marqa, Mohamad Feras; Caudrelier, Jean-Michel; Betrouni, Nacim

    2012-01-01

    To develop a dose verification tool for high-dose-rate interstitial brachytherapy treatment planning in accelerated partial breast irradiation. We have developed a software tool for interstitial brachytherapy treatment planning assessment. The software contains a database of seven (192)Ir source models and is able to estimate the dose distribution using the Task Group 43 and the Sievert integral algorithms. Dose-volume histogram analysis and dose quality assurance (QA) criteria including conformity (COnformal INdex [COIN] and conformation number [CN]), homogeneity (homogeneity index [HI]) parameters were implemented in the software to evaluate and to compare between the doses estimated by the two algorithms and a dose extracted from an external treatment planning system (TPS). The tool was evaluated and validated on four clinical cases treated by high-dose-rate interstitial brachytherapy. The doses provided by the Task Group 43 and the Sievert integral algorithms were evaluated by establishing the dose-volume histogram analysis and then by calculating the QA criteria. The algorithms were validated by comparing the dose at different anatomic points with their corresponding dose points provided from TPS. The differences were considered in good agreement (within 5%). Pretreatment dose verification is an important step in the QA of brachytherapy accelerated partial breast irradiation. A simple, fast, and accurate method of dose verification is therefore needed. The software proposed in this study could fulfill these requirements. In addition, it is freely available for using by anyone wishing to do a QA on any TPS. Copyright © 2012 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  3. Remote afterloading high dose-rate intracavity radiotherapy for advanced maxillary cancer. Treatment with individual appliances

    Energy Technology Data Exchange (ETDEWEB)

    Horimoto, Susumu; Kakei, Masaki; Saito, Tomokatsu [Yokohama City Univ. (Japan). School of Medicine] [and others

    1998-08-01

    Seven advanced maxillary cancers, 5 squamous cell carcinomas, and 2 adenoid cystic carcinomas were treated with remote afterloading high dose-rate intracavity radiotherapy. For treatment, we fabricated individual dental acrylic appliances for the postoperative area of the oral cavity. Because the appliance was specially matched to the remaining maxillary structures, radiation doses to the treated area were easily reproduced without distress to the patient. However, minor or major complications (moderate or severe mucositis and osteoradionecrosis) were observed in all patients. In this study, the number of patients was too small to assess the significance of this treatment. Nevertheless, with improvements, we think that remote afterloading high dose-rate intracavity radiotherapy with a dental acrylic appliance will soon be used to treat advanced maxillary carcinoma. (author)

  4. Perioperative Interstitial High-Dose-Rate Brachytherapy for the Treatment of Recurrent Keloids

    DEFF Research Database (Denmark)

    Jiang, Ping; Baumann, René; Dunst, Jürgen

    2016-01-01

    PURPOSE: To prospectively evaluate high-dose-rate brachytherapy in the treatment of therapy-resistant keloids and report first results, with emphasis on feasibility and early treatment outcome. METHODS AND MATERIALS: From 2009 to 2014, 24 patients with 32 recurrent keloids were treated...... with immediate perioperative high-dose-rate brachytherapy; 3 patients had been previously treated with adjuvant external beam radiation therapy and presented with recurrences in the pretreated areas. Two or more different treatment modalities had been tried in all patients and had failed to achieve remission....... After (re-)excision of the keloids, a single brachytherapy tube was placed subcutaneously before closing the wound. The target volume covered the scar in total length. Brachytherapy was given in 3 fractions with a single dose of 6 Gy in 5 mm tissue depth. The first fraction was given within 6 hours...

  5. Salvage high-dose-rate interstitial brachytherapy for locally recurrent rectal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Pellizzon, Antonio Cassio Assis, E-mail: acapellizzon@hcancer.org.br [A.C. Camargo Cancer Center, Sao Paulo, SP (Brazil). Departamento de Radioterapia

    2016-05-15

    For tumors of the lower third of the rectum, the only safe surgical procedure is abdominal-perineal resection. High-dose-rate interstitial brachytherapy is a promising treatment for local recurrence of previously irradiated lower rectal cancer, due to the extremely high concentrated dose delivered to the tumor and the sparing of normal tissue, when compared with a course of external beam radiation therapy. (author)

  6. Development of computerized dose planning system and applicator for high dose rate remote afterloading irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Choi, T. J. [Keimyung Univ., Taegu (Korea); Kim, S. W. [Fatima Hospital, Taegu (Korea); Kim, O. B.; Lee, H. J.; Won, C. H. [Keimyung Univ., Taegu (Korea); Yoon, S. M. [Dong-a Univ., Pusan (Korea)

    2000-04-01

    To design and fabricate of the high dose rate source and applicators which are tandem, ovoids and colpostat for OB/Gyn brachytherapy includes the computerized dose planning system. Designed the high dose rate Ir-192 source with nuclide atomic power irradiation and investigated the dose characteristics of fabricated brachysource. We performed the effect of self-absorption and determining the gamma constant and output factor and determined the apparent activity of designed source. he automated computer planning system provided the 2D distribution and 3D includes analysis programs. Created the high dose rate source Ir-192, 10 Ci(370GBq). The effective attenuation factor from the self-absorption and source wall was examined to 0.55 of the activity of bare source and this factor is useful for determination of the apparent activity and gamma constant 4.69 Rcm{sup 2}/mCi-hr. Fabricated the colpostat was investigated the dose distributions of frontal, axial and sagittal plane in intra-cavitary radiation therapy for cervical cancer. The reduce dose at bladder and rectum area was found about 20 % of original dose. The computerized brachytherapy planning system provides the 2-dimensional isodose and 3-D include the dose-volume histogram(DVH) with graphic-user-interface mode. emoted afterloading device was built for experiment of created Ir-192 source with film dosimetry within {+-}1 mm discrepancy. 34 refs., 25 figs., 11 tabs. (Author)

  7. Pediatric peri-operative fractionated high-dose-rate brachytherapy for recurrent Wilms’ tumor using a reconstructed Freiburg flap

    Directory of Open Access Journals (Sweden)

    Emily Flower

    2016-10-01

    Full Text Available Purpose : To report peri-operative fractionated high-dose-rate (HDR brachytherapy with a 3D customized Freiburg flap applicator to treat locally recurrent Wilms’ tumor, followed by immediate hyperthermic intraperitoneal chemotherapy for a 16-year-old with a second recurrence of nephroblastoma (Wilms’ tumor. Material and methods: The tumor was excised and surgical bed was treated with fractionated HDR brachytherapy using a Freiburg flap applicator. Hyperthermic intraperitoneal chemotherapy was performed immediately after the removal of brachytherapy applicator. Results: The Freiburg flap was successfully reconstructed to enable delivery of conformable peri-operative HDR brachytherapy. The clinical target volume (CTV D90 was 26 Gy in 5 fractions. Conclusions : Peri-operative fractionated HDR brachytherapy with a customized Freiburg flap applicator was delivered successfully across a large multi-disciplinary team.

  8. A model for low dose effects of low-LET radiation delivered at high dose rates

    Science.gov (United States)

    Schöllnberger, H.; Stewart, R.D.; Mitchel, R.E.J.

    2011-01-01

    In vitro studies show that protective tumour-reducing effects occur for low dose rates (mGy per minute). To account for these phenomena, we have previously developed stochastic and deterministic multi-stage cancer models that include radiation-induced adaptations in DNA repair processes and radical scavenging. Here, these models are extended to account for the induction of radioprotective mechanisms for low doses of low LET radiation delivered at high dose rates. Cellular adaptations in DNA repair are related to temporal changes in the amount of DNA damage in a cell. The combined effects of endogenous DNA damage, background radiation and artificial irradiation are considered. PMID:22318364

  9. Effects of high dose rate gamma radiation on survival and reproduction of Biomphalaria glabrata

    Energy Technology Data Exchange (ETDEWEB)

    Cantinha, Rebeca S.; Nakano, Eliana [Instituto Butantan, Sao Paulo, SP (Brazil). Lab. de Parasitologia], e-mail: rebecanuclear@gmail.com, e-mail: eliananakano@butantan.gov.br; Borrely, Sueli I. [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Sao Paulo, SP (Brazil). Centro de Tecnologia das Radiacoes], e-mail: sborrely@ipen.br; Amaral, Ademir; Melo, Ana M.M.A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia (GERAR)], e-mail: amaral@ufpe.br; Silva, Luanna R.S. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia. Lab. de Radiobiologia], e-mail: amdemelo@hotmail.com, e-mail: luannaribeiro_lua@hotmail.com

    2009-07-01

    Ionizing radiations are known as mutagenic agents, causing lethality and infertility. This characteristic has motivated its application on animal biological control. In this context, the freshwater snail Biomphalaria glabrata can be considered an excellent experimental model to study effects of ionizing radiations on lethality and reproduction. This work was designed to evaluate effects of {sup 60}Co gamma radiation at high dose rate (10.04 kGy/h) on B. glabrata. For this purpose, adult snails were selected and exposed to doses ranging from 20 to 100 Gy, with 10 Gy intervals; one group was kept as control. There was not effect of dose rate in the lethality of gamma radiation; the value of 64,3 Gy of LD{sub 50} obtained in our study was similar to that obtained by other authors with low dose rates. Nevertheless, our data suggest that there was a dose rate effect in the reproduction. On all dose levels, radiation improved the production of embryos for all exposed individuals. However, viability indexes were below 6% and, even 65 days after irradiation, fertility was not recovered. These results are not in agreement with other studies using low dose rates. Lethality was obtained in all groups irradiated, and the highest doses presented percentiles of dead animals above 50%. The results demonstrated that doses of 20 and 30 Gy were ideal for population control of B. glabrata. Further studies are needed; nevertheless, this research evidenced great potential of high dose rate gamma radiation on B. glabrata reproductive control. (author)

  10. Chromosomal Aberrations in Normal and AT Cells Exposed to High Dose of Low Dose Rate Irradiation

    Science.gov (United States)

    Kawata, T.; Shigematsu, N.; Kawaguchi, O.; Liu, C.; Furusawa, Y.; Hirayama, R.; George, K.; Cucinotta, F.

    2011-01-01

    Ataxia telangiectasia (A-T) is a human autosomally recessive syndrome characterized by cerebellar ataxia, telangiectases, immune dysfunction, and genomic instability, and high rate of cancer incidence. A-T cell lines are abnormally sensitive to agents that induce DNA double strand breaks, including ionizing radiation. The diverse clinical features in individuals affected by A-T and the complex cellular phenotypes are all linked to the functional inactivation of a single gene (AT mutated). It is well known that cells deficient in ATM show increased yields of both simple and complex chromosomal aberrations after high-dose-rate irradiation, but, less is known on how cells respond to low-dose-rate irradiation. It has been shown that AT cells contain a large number of unrejoined breaks after both low-dose-rate irradiation and high-dose-rate irradiation, however sensitivity for chromosomal aberrations at low-dose-rate are less often studied. To study how AT cells respond to low-dose-rate irradiation, we exposed confluent normal and AT fibroblast cells to up to 3 Gy of gamma-irradiation at a dose rate of 0.5 Gy/day and analyzed chromosomal aberrations in G0 using fusion PCC (Premature Chromosomal Condensation) technique. Giemsa staining showed that 1 Gy induces around 0.36 unrejoined fragments per cell in normal cells and around 1.35 fragments in AT cells, whereas 3Gy induces around 0.65 fragments in normal cells and around 3.3 fragments in AT cells. This result indicates that AT cells can rejoin breaks less effectively in G0 phase of the cell cycle? compared to normal cells. We also analyzed chromosomal exchanges in normal and AT cells after exposure to 3 Gy of low-dose-rate rays using a combination of G0 PCC and FISH techniques. Misrejoining was detected in the AT cells only? When cells irradiated with 3 Gy were subcultured and G2 chromosomal aberrations were analyzed using calyculin-A induced PCC technique, the yield of unrejoined breaks decreased in both normal and AT

  11. Ureteral stent insertion for gynecologic interstitial high-dose-rate brachytherapy.

    Science.gov (United States)

    Demanes, D Jeffrey; Banerjee, Robyn; Cahan, Benjamin L; Lee, Steve P; Park, Sang-June; Fallon, Julia M; Reyes, Paula; Van, Thanh Q; Steinberg, Michael L; Kamrava, Mitchell R

    2015-01-01

    To determine the utility of ureteral stents in interstitial gynecological brachytherapy. We reviewed 289 patients with cervix cancer treated with high-dose-rate interstitial brachytherapy who did not have pretreatment hydronephrosis to determine the relative incidence of benign ureteral strictures after treatment. We also did comparative dosimetry analysis in five cases of high-dose-rate brachytherapy. Bilateral ureteral stents were placed during the procedure. Three dosimetry plans were created to determine the impact of modifying clinical target volume (CTV) and applying ureteral dose constraints. In Plan 1, the ureters were contoured and excluded from the CTV and 120% dose constraints were applied. In Plan 2, the ureters were contoured and excluded, but no dose constraints were applied to the ureter. In Plan 3, the CTV was created as if the location of the ureters was unknown and then ureteral dose was determined. There were 11 ureteral strictures observed in 255 nonstented cases and 0 ureteral strictures in 34 stented cases. Plan 1 reduced the ureter dose (D(0.1cc)) by a median 22% (7.0-53.8%) compared with Plan 2 and by a median of 30.9% (12.3-65%). compared with Plan 3. Placement of stents and ureteral dose constraints facilitates dosimetry and reduces the dose to ureters. Temporary ureteral stents prevent obstruction during interstitial gynecologic brachytherapy and allows the ureters to be addressed as an organ at risk. Copyright © 2015. Published by Elsevier Inc.

  12. Introduction of novel 3D-printed superficial applicators for high-dose-rate skin brachytherapy.

    Science.gov (United States)

    Jones, Emma-Louise; Tonino Baldion, Anna; Thomas, Christopher; Burrows, Tom; Byrne, Nick; Newton, Victoria; Aldridge, Sarah

    Custom-made surface mold applicators often allow more flexibility when carrying out skin brachytherapy, particularly for small treatment areas with high surface obliquity. They can, however, be difficult to manufacture, particularly if there is a lack of experience in superficial high-dose-rate brachytherapy techniques or with limited resources. We present a novel method of manufacturing superficial brachytherapy applicators utilizing three-dimensional (3D)-printing techniques. We describe the treatment planning process and the process of applicator manufacture. The treatment planning process, with the introduction of a pre-plan, allows for an "ideal" catheter arrangement within an applicator to be determined, exploiting varying catheter orientations, heights, and curvatures if required. The pre-plan arrangement is then 3D printed to the exact specifications of the pre-plan applicator design. This results in improved target volume coverage and improved sparing of organs at risk. Using a pre-plan technique for ideal catheter placement followed by automated 3D-printed applicator manufacture has greatly improved the entire process of superficial high-dose-rate brachytherapy treatment. We are able to design and manufacture flexible, well-fitting, superior quality applicators resulting in a more efficient and improved patient pathway and patient experience. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  13. Perioperative high-dose-rate interstitial brachytherapy boost for patients with early breast cancer.

    Science.gov (United States)

    Sharma, Daya Nand; Deo, S V S; Rath, Goura Kisor; Shukla, Nootan Kumar; Thulkar, Sanjay; Madan, Renu; Julka, Pramod Kumar

    2013-01-01

    To evaluate the clinical results of perioperative high-dose-rate interstitial brachytherapy boost treatment preceding whole breast external beam radiation therapy in patients with early breast cancer. From 2005-2010, 100 patients with early breast cancer who met the eligibility criteria were enrolled in the study. Brachytherapy implant was performed during the breast-conserving surgery procedure. The boost treatment was started on the 3rd postoperative day to deliver a dose of 15 Gy in 6 fractions over 3 days. Three weeks later, external beam radiation therapy to the whole breast was started for a prescription dose of 50 Gy. The study end points were local recurrence, acute toxicity and cosmetic outcome. Median age of the patients was 46 years, and median follow-up was 52 months. No patient developed a local recurrence but 5 patients developed distant metastases. The 5-year overall survival and disease-free survival were 86% and 77%, respectively. Eleven patients had acute toxicity; 4 wound complications and 7 grade III skin toxicity. Nine of the 11 patients had breast size of more than 1500 cc. Except for the breast volume (>1500 cc), there was no statistically significant correlation between any of the patient or dosimetry-related factors and acute toxicity. Good-excellent cosmesis was observed in 87% of patients. Perioperative high-dose-rate interstitial brachytherapy boost followed by whole breast external beam radiation therapy provides excellent local control, acceptable acute toxicity and good-excellent breast cosmesis in patients with early breast cancer.

  14. Experiences of high dose rate interstitial brachytherapy for carcinoma of the mobile tongue

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Hiroshi; Inoue, Toshihiko; Yamazaki, Hideya (Osaka Univ. (Japan). Faculty of Medicine) (and others)

    1994-03-01

    Interstitial brachytherapy was conducted for mobile tongue carcinoma using a high dose rate remote afterloading machine with small [sup 192]I source. Detailed method, named as 'linked double-botton technique', is to approach from submandibular skin by an open-ended stainless steel needles to the tongue lesion, and to replace each needle into flexible nylon tube from the oral cavity. Delivered dose was 60 Gy/10 Fr./5-6 days at the distance 5 mm from the source plane. Ten patients with mobile tongue carcinoma Tl-2N0 were treated with this method from October 1991 through August 1992. Local was uncontrolled in one patient, in whom the lesion was combined with leukoplakia at both lateral borders of the tongue. This was in accordance with the result in low dose rate treatment. This can be a substitute to low dose rate system for treatment of mobile tongue carcinoma. (author).

  15. High-dose rate Ir-192 interstitial brachytherapy for recurrent pelvic tumors

    Energy Technology Data Exchange (ETDEWEB)

    Tsukiyama, Iwao; Katano, Susumu; Kotake, Kenjiro; Yamamoto, Seiichiro; Kamata, Hiroyuki; Sekiguchi, Isao [Tochigi Cancer Center, (Japan); Furuta, Masaya; Ohno, Tatsuya

    1999-06-01

    Recurrent pelvic tumors are difficult to control with external irradiation alone. We have conducted phase I and II clinical trials against recurrent pelvic tumors. From January 1995 through March 1997, 13 recurrent pelvic tumors in 10 patients were treated with high-dose rate Ir-192 interstitial brachytherapy. Complete responses were achieved for 2 tumors, partial responses for 5 tumors, and no response for 6 tumors; therefore, the response rate was 61% (8 of 13 tumors). Treatment-related morbidity was noted in 5 patients and included one case each of skin ulcer, rectovaginal fistula, sacral abscess, rectal bleeding, and vesicovaginal fistula. In January 1999, four patients were alive and had survived for 17, 18, 28, and 46 months. Six patients had died but had survived 4, 13, 15, 16, and 27 months. (author)

  16. Adjuvant high dose rate brachytherapy for soft tissue sarcomas: initial experience report

    Directory of Open Access Journals (Sweden)

    Robert Whitfield

    2011-03-01

    Full Text Available Purpose: Adjuvant high-dose-rate brachytherapy (HDRBT offers advantages over low dose rate brachytherapy (LDRBT, although there are little data on local tumor control and treatment related toxicity. We report outcome in patients with primary, recurrent, and metastatic extremity and superficial trunk soft tissue sarcoma. Material and methods: Eleven patients (12 sites with intermediate or high grade sarcoma were treated with adjuvant HDRBT following surgical resection. Patients were treated at 3.4 Gy fractions delivered twice daily to a total dose of 34 Gy (1 patient received 9 fractions. Results: With median follow-up of 20.8 months, 1 patient developed a local recurrence. 2-year local control and overall survival are 89% and 71%, respectively. Wound complications occurred in 3 sites. Two of the wound complications developed in the area of previous external beam radiotherapy (EBRT. Conclusion: Surgical resection followed by HDRBT is associated with excellent early local tumor control and acceptable wound complication.

  17. Non-melanoma skin cancer treated with high-dose-rate brachytherapy: a review of literature.

    Science.gov (United States)

    Delishaj, Durim; Rembielak, Agata; Manfredi, Bruno; Ursino, Stefano; Pasqualetti, Francesco; Laliscia, Concetta; Orlandi, Francesca; Morganti, Riccardo; Fabrini, Maria Grazia; Paiar, Fabiola

    2016-12-01

    The incidence of non-melanoma skin cancer (NMSC) has been increasing over the past 30 years. There are different treatment options and surgical excision is the most frequent treatment due to its low rates of recurrence. Radiotherapy is an effective alternative of surgery, and brachytherapy (BT) might be a better therapeutic option due to high radiation dose concentration to the tumor with rapid dose fall-off resulting in normal tissues sparing. The aim of this review was to evaluate the local control, toxicity, and cosmetic outcomes in NMSC treated with high-dose-rate BT (HDR-BT). In May 2016, a systematic search of bibliographic database of PubMed, Web of Science, Scopus, and Cochrane Library with a combination of key words of "skin cancer", "high dose rate brachytherapy", "squamous cell carcinoma", "basal cell carcinoma", and "non melanoma skin cancer" was performed. In this systematic review, we included randomized trials, non-randomized trials, prospective and retrospective studies in patients affected by NMSC treated with HDR-BT. Our searches generated a total of 85 results, and through a process of screening, 10 publications were selected for the review. Brachytherapy was well tolerated with acceptable toxicity and high local control rates (median: 97%). Cosmetic outcome was reported in seven study and consisted in an excellent and good cosmetic results in 94.8% of cases. Based on the review data, we can conclude that the treatment of NMSC with HDR-BT is effective with excellent and good cosmetics results, even in elderly patients. The hypofractionated course appears effective with very good local disease control. More data with large-scale randomized controlled trials are needed to assess the efficacy and safety of brachytherapy.

  18. Non-melanoma skin cancer treated with high-dose-rate brachytherapy: a review of literature

    Directory of Open Access Journals (Sweden)

    Durim Delishaj

    2016-12-01

    Full Text Available Purpose: The incidence of non-melanoma skin cancer (NMSC has been increasing over the past 30 years. There are different treatment options and surgical excision is the most frequent treatment due to its low rates of recurrence. Radiotherapy is an effective alternative of surgery, and brachytherapy (BT might be a better therapeutic option due to high radiation dose concentration to the tumor with rapid dose fall-off resulting in normal tissues sparing. The aim of this review was to evaluate the local control, toxicity, and cosmetic outcomes in NMSC treated with high-dose-rate BT (HDR-BT. Material and methods: In May 2016, a systematic search of bibliographic database of PubMed, Web of Science, Scopus, and Cochrane Library with a combination of key words of “skin cancer”, “high dose rate brachytherapy”, “squamous cell carcinoma”, “basal cell carcinoma”, and “non melanoma skin cancer“ was performed. In this systematic review, we included randomized trials, non-randomized trials, prospective and retrospective studies in patients affected by NMSC treated with HDR-BT. Results: Our searches generated a total of 85 results, and through a process of screening, 10 publications were selected for the review. Brachytherapy was well tolerated with acceptable toxicity and high local control rates (median: 97%. Cosmetic outcome was reported in seven study and consisted in an excellent and good cosmetic results in 94.8% of cases. Conclusions : Based on the review data, we can conclude that the treatment of NMSC with HDR-BT is effective with excellent and good cosmetics results, even in elderly patients. The hypofractionated course appears effective with very good local disease control. More data with large-scale randomized controlled trials are needed to assess the efficacy and safety of brachytherapy.

  19. High dose rate brachytherapy with customized applicators for malignant facial skin lesions.

    Science.gov (United States)

    Jumeau, R; Renard-Oldrini, S; Courrech, F; Buchheit, I; Oldrini, G; Vogin, G; Peiffert, D

    2016-07-01

    Brachytherapy is a well-known treatment in the management of skin tumors. For facial or scalp lesions, applicators have been developed to deliver non-invasive treatment. We present cases treated with customized applicators with high dose rate system. Patients with poor performance status treated for malignant skin lesions of the scalp or the facial skin between 2011 and 2014 were studied. Afterloading devices were chosen between Freiburg(®) Flap, silicone-mold or wax applicators. The clinical target volume (CTV) was created by adding margins to lesions (10mm to 20mm). The dose schedules were 25Gy in five fractions for postoperative lesions, 30Gy in six fractions for exclusive treatments and a single session of 8Gy could be considered for palliative treatments. In 30 months, 11 patients received a treatment for a total of 12 lesions. The median age was 80 years. The median follow-up was 17 months and the 2-year local control rate was 91%. The mean CTV surface was 41.1cm(2) with a mean thickness of 6.1mm. We conceived three wax applicators, used our silicone-mold eight times and the Freiburg(®) Flap one time. We observed only low-grade radiodermitis (grade I: 50%, grade II: 33%), and no high-grade skin toxicity. High dose rate brachytherapy with customized applicators for facial skin and scalp lesions is efficient and safe. It is a good modality to treat complex lesions in patients unfit for invasive treatment. Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  20. Bladder–Rectum Spacer Balloon in High-Dose-Rate Brachytherapy in Cervix Carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Rai, Bhavana [Department of Radiotherapy and Oncology, Regional Cancer Centre, Postgraduate Institute of Medical Education and Research, Chandigarh (India); Patel, Firuza D., E-mail: firuzapatel@gmail.com [Department of Radiotherapy and Oncology, Regional Cancer Centre, Postgraduate Institute of Medical Education and Research, Chandigarh (India); Chakraborty, Santam; Sharma, Suresh C.; Kapoor, Rakesh [Department of Radiotherapy and Oncology, Regional Cancer Centre, Postgraduate Institute of Medical Education and Research, Chandigarh (India); Aprem, Abi Santhosh [Corporate R and D Division, HLL Lifecare Limited, Karamana, Trivandrum (India)

    2013-04-01

    Purpose: To compare bladder and rectum doses with the use of a bladder–rectum spacer balloon (BRSB) versus standard gauze packing in the same patient receiving 2 high-dose-rate intracavitary brachytherapy fractions. Methods and Materials: This was a randomized study to compare the reduction in bladder and rectum doses with the use of a BRSB compared with standard gauze packing in patients with carcinoma of the cervix being treated with high-dose-rate intracavitary brachytherapy. The patients were randomized between 2 arms. In arm A, vaginal packing was done with standard gauze packing in the first application, and BRSB was used in the second application. Arm B was the reverse of arm A. The International Commission for Radiation Units and Measurement (ICRU) point doses and doses to 0.1-cm{sup 3}, 1-cm{sup 3}, 2-cm{sup 3}, 5-cm{sup 3}, and 10-cm{sup 3} volumes of bladder and rectum were compared. The patients were also subjectively assessed for the ease of application and the time taken for application. Statistical analysis was done using the paired t test. Results: A total of 43 patients were enrolled; however, 3 patients had to be excluded because the BRSB could not be inserted owing to unfavorable local anatomy. Thus 40 patients (80 plans) were evaluated. The application was difficult in 3 patients with BRSB, and in 2 patients with BRSB the application time was prolonged. There was no significant difference in bladder doses to 0.1 cm{sup 3}, 1 cm{sup 3}, 2 cm{sup 3}, 5 cm{sup 3}, and 10 cm{sup 3} and ICRU bladder point. Statistically significant dose reductions to 0.1-cm{sup 3}, 1-cm{sup 3}, and 2-cm{sup 3} volumes for rectum were observed with the BRSB. No significant differences in 5-cm{sup 3} and 10-cm{sup 3} volumes and ICRU rectum point were observed. Conclusion: A statistically significant dose reduction was observed for small high-dose volumes in rectum with the BRSB. The doses to bladder were comparable for BRSB and gauze packing. Transparent balloons of

  1. A phantom for verification of dwell position and time of a high dose rate brachytherapy source.

    Science.gov (United States)

    Madebo, M; Pillainayagam, J; Kron, T; Franich, R

    2012-09-01

    Accuracy of dwell position and reproducibility of dwell time are critical in high dose rate (HDR) brachytherapy. A phantom was designed to verify dwell position and dwell time reproducibility for an Ir-192 HDR stepping source using Computed Radiography (CR). The central part of the phantom, incorporating thin alternating strips of lead and acrylic, was used to measure dwell positions. The outer part of the phantom features recesses containing different absorber materials (lead, aluminium, acrylic and polystyrene foam), and was used for determining reproducibility of dwell times. Dwell position errors of dwell time as low as 0.1 s, the minimum dwell time of the treatment unit, could be detected by choosing dwell times over the four materials that produce identical exposure at the CR detector.

  2. High-dose-rate (HDR) brachytherapy for the treatment of benign obstructive endobronchial granulation tissue.

    Science.gov (United States)

    Madu, Chika N; Machuzak, Michael S; Sterman, Daniel H; Musani, Ali; Ahya, Vivek; McDonough, James; Metz, James M

    2006-12-01

    Severe airway obstruction can occur in the setting of benign granulation tissue forming at bronchial anastomotic sites after lung transplantation in up to 20% of patients. Many of these benign lesions respond to stent placement, laser ablation, or balloon bronchoplasty. However, in certain cases, proliferation of granulation tissue may persist despite all therapeutic attempts. This study describes a series of refractory patients treated with high-dose-rate (HDR) brachytherapy for benign proliferation of granulation tissue, causing airway compromise. Between April 2002 and June 2005, 5 patients with significant airway compromise from recurrent granulation tissue were treated with HDR brachytherapy. All patients had previously failed to maintain a patent airway despite multiple bronchoscopic interventions. Treatment was delivered using an HDR brachytherapy afterloader with (192)Ir. Dose prescription was to a depth of 1 cm. All patients were treated weekly, with total doses ranging from 10 Gy to 21 Gy in two to three fractions. The median follow-up was 12 months. All patients experienced a reduction in therapeutic bronchoscopic procedures after HDR brachytherapy compared with the pretreatment period. With the exception of possible radiation-induced bronchitis in 1 patient, there were no other treatment related complications. At the time of this report, 2 patients have died and the other 3 are alive with marked symptomatic improvement and reduced bronchoscopic procedures. High-dose-rate brachytherapy is an effective treatment for benign proliferation of granulation tissue causing airway obstruction. The early response to therapy is encouraging and further follow-up is necessary to determine long-term durability and late effects.

  3. Bladder wall recurrence of prostate cancer after high-dose-rate brachytherapy.

    Science.gov (United States)

    Raleigh, David R; Hsu, I-Chow; Braunstein, Steve; Chang, Albert J; Simko, Jeffry P; Roach, Mack

    2015-01-01

    Prostate cancer seeding after needle biopsy has been reported in the perineum, rectal wall, and periprostatic soft tissue. In this article, we report the results of a localized prostate cancer recurrence in the bladder following protrusion of a single high-dose-rate brachytherapy catheter through the bladder wall at the ultimate site of failure. A 62-year-old man with high-risk prostate adenocarcinoma was treated with long-term androgen deprivation therapy, intensity-modulated radiation, and high-dose-rate brachytherapy boost. He developed biochemical recurrence 4 years after treatment, and a CT scan of the pelvis revealed a nodule in the posterior, inferior bladder wall. Surgical pathology following transurethral resection of tumor within the bladder was consistent with high-grade prostate adenocarcinoma. The patient's prostate-specific antigen level fell to the range of normal postoperatively, and whole body imaging, including a multi-parametric MRI of the prostate with diffusion and spectroscopy, failed to reveal any other sites of disease. Review of the CT scan obtained for dosimetry at the time of brachytherapy demonstrated a lone catheter protruding through the bladder wall at the site of eventual recurrence. The tumor recurred in the bladder 12 months later, once more without evidence of disease within the prostate itself or distantly, and the patient was started on salvage androgen deprivation therapy. This case is the first report of prostate cancer recurrence in the bladder wall after brachytherapy and raises questions about prostate cancer biology, brachytherapy technique, and the timing of brachytherapy boost relative to whole pelvic radiotherapy for prostate cancer. Published by Elsevier Inc.

  4. Quality control of high-dose-rate brachytherapy: treatment delivery analysis using statistical process control.

    Science.gov (United States)

    Able, Charles M; Bright, Megan; Frizzell, Bart

    2013-03-01

    Statistical process control (SPC) is a quality control method used to ensure that a process is well controlled and operates with little variation. This study determined whether SPC was a viable technique for evaluating the proper operation of a high-dose-rate (HDR) brachytherapy treatment delivery system. A surrogate prostate patient was developed using Vyse ordnance gelatin. A total of 10 metal oxide semiconductor field-effect transistors (MOSFETs) were placed from prostate base to apex. Computed tomography guidance was used to accurately position the first detector in each train at the base. The plan consisted of 12 needles with 129 dwell positions delivering a prescribed peripheral dose of 200 cGy. Sixteen accurate treatment trials were delivered as planned. Subsequently, a number of treatments were delivered with errors introduced, including wrong patient, wrong source calibration, wrong connection sequence, single needle displaced inferiorly 5 mm, and entire implant displaced 2 mm and 4 mm inferiorly. Two process behavior charts (PBC), an individual and a moving range chart, were developed for each dosimeter location. There were 4 false positives resulting from 160 measurements from 16 accurately delivered treatments. For the inaccurately delivered treatments, the PBC indicated that measurements made at the periphery and apex (regions of high-dose gradient) were much more sensitive to treatment delivery errors. All errors introduced were correctly identified by either the individual or the moving range PBC in the apex region. Measurements at the urethra and base were less sensitive to errors. SPC is a viable method for assessing the quality of HDR treatment delivery. Further development is necessary to determine the most effective dose sampling, to ensure reproducible evaluation of treatment delivery accuracy. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Postoperative single-dose interstitial high-dose-rate brachytherapy in therapy-resistant keloids.

    Science.gov (United States)

    Hafkamp, C J H; Lapid, O; Dávila Fajardo, R; van de Kar, A L; Koedooder, C; Stalpers, L J; Pieters, B R

    Patients with keloids complain of the cosmetic aspect, pain, and pruritus. Many different therapies are being used for keloids. The aim of this study was to evaluate the recurrence rate and outcome after resection followed by a single-dose brachytherapy. Patients treated by resection of the keloid plus a single dose of 13 Gy high-dose-rate brachytherapy were evaluated at least 1 year after treatment. Clinical response and cosmesis were assessed by a plastic surgeon and by the patients using the Patient and Observer Scar Assessment Scale. Only 24 of the 61 invited patients responded to participate with the study; 29 keloids were evaluated. The recurrence rate was 24.1% after a median followup of 53 months (19-95 months). Patients scored on average 24.3 for their total Patient and Observer Scar Assessment Scale score (range 6-52), whereas the observer scored on average 14.6 (range 6-42). This treatment has a higher recurrence rate than that reported in most other studies. This may be explained by differences in recurrence definition, differences in followup time among studies, and selection bias because of not contributing to the study. The cosmetic outcome for evaluated patients is relatively good. This treatment policy has the advantage that patients are treated in a single day. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  6. Verification of SuperMC for simulation of a high-dose-rate brachytherapy source

    Science.gov (United States)

    Naeem, Hamza; Wasaye, Muhammad Abdul; Chen, Chaobin; Zheng, Huaqing; Hao, Lijuan

    2017-06-01

    In this study, SuperMC (Super Monte Carlo simulation program for nuclear and radiation simulation) was tested and verified for simulation of a high-dose-rate brachytherapy source. The Monte Carlo simulation includes calculations of the air kerma strength, dose rate constant, radial dose function and anisotropy function as recommended by the American Association of Physicists in Medicine (AAPM) in Task Group reports 43 and 43U1 (TG-43, TG-43U1). The air kerma strength, dose rate constant, radial dose function and anisotropy function were compared with previously published Monte Carlo simulation results and experimental data. The calculated parameters were found to be in good agreement with published Monte Carlo and measured data. The value obtained from the SuperMC simulation for the air kerma strength was 9.779 × 10-8 U·Bq-1 and the dose rate constant was 1.1092 ± 0.02% cGy·h-1·U-1. The time to transport 5 × 107 photons showed SuperMC to be relatively faster than MCNP. The results show that SuperMC can be used for fast and accurate simulations and dosimetric calculations of HDR brachytherapy sources.

  7. Comparative dosimetry of GammaMed Plus high-dose rate Ir brachytherapy source.

    Science.gov (United States)

    Patel, N P; Majumdar, B; Vijayan, V

    2010-07-01

    The comparative dosimetry of GammaMed (GM) Plus high-dose rate brachytherapy source was performed by an experiment using 0.1-cc thimble ionization chamber and simulation-based study using EGSnrc code. In-water dose measurements were performed with 0.1-cc chamber to derive the radial dose function (r = 0.8 to 20.0 cm) and anisotropy function (r = 5.0 cm with polar angle from 10° to 170°). The nonuniformity correction factor for 0.1-cc chamber was applied for in-water measurements at shorter distances from the source. The EGSnrc code was used to derive the dose rate constant (Λ), radial dose function g(L)(r) and anisotropy function F(r, θ) of GM Plus source. The dosimetric data derived using EGSnrc code in our study were in very good agreement relative to published data for GM Plus source. The radial dose function up to 12 cm derived from measured dose using 0.1-cc chamber was in agreement within ±3% of data derived by the simulation study.

  8. High-dose-rate interstitial brachytherapy for the treatment of penile carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Petera, J.; Odrazka, K.; Zouhar, M.; Bedrosova, J.; Dolezel, M. [Dept. of Oncology and Radiotherapy, Charles Univ. Medical School and Teaching Hospital, Hradec Kralove (Czech Republic)

    2004-02-01

    Background: interstitial low-dose-rate (LDR) brachytherapy allows conservative treatment of T1-T2 penile carcinoma. High-dose-rate (HDR) is often considered to be dangerous for interstitial implants because of a higher risk of complications, but numerous reports suggest that results may be comparable to LDR. Nevertheless, there are no data in the literature available regarding HDR interstitial brachytherapy for carcinoma of the penis. Case report: a 64-year-old man with T1 NO MO epidermoid carcinoma of the glans is reported. Interstitial HDR brachytherapy was performed using the stainless hollow needle technique and a breast template for fixation and good geometry. The dose delivered was 18 x 3 Gy twice daily. Results: after 232 days from brachytherapy, the patient was without any evidence of the tumor, experienced no serious radiation-induced complications, and had a fully functional organ. Conclusion: HDR interstitial brachytherapy is feasible in selected case of penis carcinoma, when careful planning and small single fractions are used. (orig.)

  9. 3D-printed applicators for high dose rate brachytherapy: Dosimetric assessment at different infill percentage.

    Science.gov (United States)

    Ricotti, Rosalinda; Vavassori, Andrea; Bazani, Alessia; Ciardo, Delia; Pansini, Floriana; Spoto, Ruggero; Sammarco, Vittorio; Cattani, Federica; Baroni, Guido; Orecchia, Roberto; Jereczek-Fossa, Barbara Alicja

    2016-12-01

    Dosimetric assessment of high dose rate (HDR) brachytherapy applicators, printed in 3D with acrylonitrile butadiene styrene (ABS) at different infill percentage. A low-cost, desktop, 3D printer (Hamlet 3DX100, Hamlet, Dublin, IE) was used for manufacturing simple HDR applicators, reproducing typical geometries in brachytherapy: cylindrical (common in vaginal treatment) and flat configurations (generally used to treat superficial lesions). Printer accuracy was investigated through physical measurements. The dosimetric consequences of varying the applicator's density by tuning the printing infill percentage were analysed experimentally by measuring depth dose profiles and superficial dose distribution with Gafchromic EBT3 films (International Specialty Products, Wayne, NJ). Dose distributions were compared to those obtained with a commercial superficial applicator. Measured printing accuracy was within 0.5mm. Dose attenuation was not sensitive to the density of the material. Surface dose distribution comparison of the 3D printed flat applicators with respect to the commercial superficial applicator showed an overall passing rate greater than 94% for gamma analysis with 3% dose difference criteria, 3mm distance-to-agreement criteria and 10% dose threshold. Low-cost 3D printers are a promising solution for the customization of the HDR brachytherapy applicators. However, further assessment of 3D printing techniques and regulatory materials approval are required for clinical application. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  10. Fractionated high-dose-rate brachytherapy in the management of uterine cervical cancer.

    Science.gov (United States)

    Park, Hee-Chul; Suh, Chang Ok; Kim, Gwi Eon

    2002-12-01

    It is well known that intracavitary radiotherapy (ICR), either alone or in combination with external-beam radiotherapy (EBRT) is an essential component of the radiation treatment of uterine cervical cancer. Although low-dose-rate (LDR) brachytherapy has been successfully applied to the management of such patients, several radiation oncologists have experience of using high-dose-rate (HDR) brachytherapy with promising clinical results over the past 4 decades. However, there has been a considerable reluctance by radiation oncologists and gynecologists in North America to employ the HDR remote afterloading technique instead of the more firmly established LDR treatment modality. In contrast, the HDR-ICR system is rapidly gaining acceptance in Korea since the introduction of the Ralstron, remotely controlled afterloading system using HDR Co-60 sources, at the Yonsei Cancer Center in 1979. According to brachytherapy statistics reported by the Korean Society of Therapeutic Radiology and Oncology, in 1997, brachytherapy was performed upon 1,758 Korean patients with uterine cervical cancer, of whom approximately 83% received HDR brachytherapy. In this review, we present our experiences of HDR-ICR for the treatment of uterine cervical cancer. In addition, we discuss the controversial points, which are raised by those considering the use of HDR-ICR for uterine cervical cancer; these issues include physical and radiobiological considerations, and the prospect of future technical improvements.

  11. Salvage high-dose-rate brachytherapy for esophageal cancer in previously irradiated patients: A retrospective analysis.

    Science.gov (United States)

    Wong Hee Kam, Stéphanie; Rivera, Sofia; Hennequin, Christophe; Lourenço, Nelson; Chirica, Mircea; Munoz-Bongrand, Nicolas; Gornet, Jean-Marc; Quéro, Laurent

    2015-01-01

    To evaluate outcomes after exclusive salvage high-dose-rate (HDR) intraluminal esophageal brachytherapy given to previously irradiated patients with recurrent esophageal cancer. We reviewed medical records of 30 patients who were treated by salvage HDR brachytherapy for local esophageal cancer. Brachytherapy delivered four to six fractions of 5-7 Gy at 5 mm from the applicator surface and 20 mm above and below the macroscopic tumor volume. Eighty percentage of patients received treatment as initially planned. Complete response rate, evaluated 1 month after brachytherapy by endoscopy and biopsy, was 53%. Squamous histology and complete endoscopic tumor response at 1 month were significantly associated with better local tumor control. Median local progression-free survival was 9.8 months. Overall survival was 31.5% and 17.5% at 1 and 2 years, respectively. On univariate analysis, preserved performance status and limited weight loss (brachytherapy were associated with better overall survival. Severe toxicity (Grade ≥3) occurred in 7 patients (23%). Although esophageal cancer in previously irradiated patients is associated with poor outcomes, HDR brachytherapy may be a valuable salvage treatment for inoperable patients with locally limited esophageal cancer, particularly in the subset of patients with preserved performance status and limited weight loss (≤10%) before salvage brachytherapy. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  12. Prognostic factors in squamous cell lip carcinoma treated with high-dose-rate brachytherapy.

    Science.gov (United States)

    Guinot, Jose-Luis; Arribas, Leoncio; Vendrell, Juan B; Santos, Miguel; Tortajada, Maria I; Mut, Alejandro; Cruz, Julia; Mengual, Jose L; Chust, Maria L

    2014-12-01

    The purpose of this study was for us to present our analysis of the results and prognostic factors in squamous lip carcinoma treated with high-dose-rate (HDR) brachytherapy. From 1999 to 2010, 102 patients were treated with HDR-brachytherapy, 54 with T1, 33 with T2, and 15 with T4. Eight cases were N+. Twenty-one patients were treated with surgery plus brachytherapy because of close/positive margins. Nine fractions of 5 Gy were given over 5 days in 67% of the patients. Elective neck treatment was performed in 23 cases. The 10-year actuarial local control was 94.6%, nodal regional control was 88.6%, disease-free survival was 84.6%, and cause-specific survival was 93.2%. In the univariate analysis, T4 tumors had higher risk of local failure and T2 of regional relapse. In the multivariate analysis, skin involvement was the only significant factor for tumor progression. HDR-brachytherapy yields excellent local control rates. Skin involvement increases the risk of local and cervical recurrence. Elective neck treatment should be done in T2 to T4 tumors or with skin or commissure involvement. © 2014 Wiley Periodicals, Inc.

  13. High dose rate 192Ir source calibration: A single institution experience

    Science.gov (United States)

    Abdullah, R.; Abdullah, N. H.; Mohamed, M.; Idris, N. R. N.; Yusoff, A. L.; Chen, S. C.; Zakaria, A.

    2017-05-01

    Measurement of source strength of new high dose rate (HDR) 192Ir supplied by the manufacturer is part of quality assurance recommended by Radiation Safety Section, Ministry of Health of Malaysia. The source strength is determined in reference air kerma rate (RAKR). The purpose of this study was to evaluate RAKR measurement of 192Ir using well-type ionisation chamber with RAKR stated in the certificate provided by the manufacturer. A retrospective study on 19 MicroSelectron HDR 192Ir Classic from 2001 to 2009 and 12 MicroSelectron HDR 192Ir V2 sources from 2009 to 2016 supplied by manufacturer were compared. From the study, the agreement between measured RAKR and RAKR stated in the certificate by manufacturer for all 32 sources supplied were within ±2.5%. As a conclusion, a threshold level of ±2.5% can be used as suitable indicator to spot problems of the brachytherapy system in Department of Nuclear Medicine Radiotherapy and Oncology, Hospital USM.

  14. Clinical outcome of high-dose-rate interstitial brachytherapy in patients with oral cavity cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sung Uk; Cho, Kwan Ho; Moon, Sung Ho; Choi, Sung Weon; Park, Joo Yong; Yun, Tak; Lee, Sang Hyun; Lim, Young Kyung; Jeong, Chi Young [National Cancer Center, Goyang (Korea, Republic of)

    2014-12-15

    To evaluate the clinical outcome of high-dose-rate (HDR) interstitial brachytherapy (IBT) in patients with oral cavity cancer. Sixteen patients with oral cavity cancer treated with HDR remote-control afterloading brachytherapy using 192Ir between 2001 and 2013 were analyzed retrospectively. Brachytherapy was administered in 11 patients as the primary treatment and in five patients as salvage treatment for recurrence after the initial surgery. In 12 patients, external beam radiotherapy (50-55 Gy/25 fractions) was combined with IBT of 21 Gy/7 fractions. In addition, IBT was administered as the sole treatment in three patients with a total dose of 50 Gy/10 fractions and as postoperative adjuvant treatment in one patient with a total of 35 Gy/7 fractions. The 5-year overall survival of the entire group was 70%. The actuarial local control rate after 3 years was 84%. All five recurrent cases after initial surgery were successfully salvaged using IBT +/- external beam radiotherapy. Two patients developed local recurrence at 3 and 5 months, respectively, after IBT. The acute complications were acceptable (< or =grade 2). Three patients developed major late complications, such as radio-osteonecrosis, in which one patient was treated by conservative therapy and two required surgical intervention. HDR IBT for oral cavity cancer was effective and acceptable in diverse clinical settings, such as in the cases of primary or salvage treatment.

  15. In vivo measurements for high dose rate brachytherapy with optically stimulated luminescent dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Renu; Jursinic, Paul A. [Department of Radiation Oncology, West Michigan Cancer Center, 200 North Park Street, Kalamazoo, Michigan 49007 (United States)

    2013-07-15

    Purpose: To show the feasibility of clinical implementation of OSLDs for high dose-rate (HDR) in vivo dosimetry for gynecological and breast patients. To discuss how the OSLDs were characterized for an Ir-192 source, taking into account low gamma energy and high dose gradients. To describe differences caused by the dose calculation formalism of treatment planning systems.Methods: OSLD irradiations were made using the GammaMedplus iX Ir-192 HDR, Varian Medical Systems, Milpitas, CA. BrachyVision versions 8.9 and 10.0, Varian Medical Systems, Milpitas, CA, were used for calculations. Version 8.9 used the TG-43 algorithm and version 10.0 used the Acuros algorithm. The OSLDs (InLight Nanodots) were characterized for Ir-192. Various phantoms were created to assess calculated and measured doses and the angular dependence and self-absorption of the Nanodots. Following successful phantom measurements, patient measurements for gynecological patients and breast cancer patients were made and compared to calculated doses.Results: The OSLD sensitivity to Ir-192 compared to 6 MV is between 1.10 and 1.25, is unique to each detector, and changes with accumulated dose. The measured doses were compared to those predicted by the treatment planning system and found to be in agreement for the gynecological patients to within measurement uncertainty. The range of differences between the measured and Acuros calculated doses was -10%-14%. For the breast patients, there was a discrepancy of -4.4% to +6.5% between the measured and calculated doses at the skin surface when the Acuros algorithm was used. These differences were within experimental uncertainty due to (random) error in the location of the detector with respect to the treatment catheter.Conclusions: OSLDs can be successfully used for HDR in vivo dosimetry. However, for the measurements to be meaningful one must account for the angular dependence, volume-averaging, and the greater sensitivity to Ir-192 gamma rays than to 6 MV x

  16. Radiolysis of confined water: hydrogen production at a high dose rate.

    Science.gov (United States)

    Le Caër, Sophie; Rotureau, Patricia; Brunet, Francine; Charpentier, Thibault; Blain, Guillaume; Renault, Jean Philippe; Mialocq, Jean-Claude

    2005-12-09

    The production of molecular hydrogen in the radiolysis of dried or hydrated nanoporous controlled-pore glasses (CPG) has been carefully studied using 10 MeV electron irradiation at high dose rate. In all cases, the H2 yield increases when the pore size decreases. Moreover, the yields measured in dried materials are two orders of magnitude smaller than those obtained in hydrated glasses. This proves that the part of the H2 coming from the surface of the material is negligible in the hydrated case. Thus, the measured yields correspond to those of nanoconfined water. Moreover, these yields are not modified by the presence of potassium bromide, which is a hydroxyl radical scavenger. This experimental observation shows that the back reaction between H2 and HO* does not take place in such confined environments. These porous materials have been characterized before and after irradiation by means of Fourier-transform infrared (FT-IR) spectroscopy, electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) techniques, which helps to understand the elementary processes taking place in this type of environment, especially the protective effect of water on the surface in the case of hydrated glasses.

  17. Assessment of dose uniformity around high dose rate 192Ir and 60Co stepping sources.

    Science.gov (United States)

    Farhood, Bagher; Ghorbani, Mahdi

    2017-12-01

    This study aimed to evaluate dose uniformity for 192Ir and 60Co stepping sources. High dose rate 192Ir and 60Co stepping sources were simulated by the MCNPX Monte Carlo code. To investigate dose uniformity, treatment lengths of 30, 50, 100, and 150 mm with stepping distances of 3, 5, 7, and 10 mm were considered. Finally, dose uniformity for the 192Ir and 60Co stepping sources with increasing distances from the source were assessed at these treatment lengths and steps. The findings showed that the dose distribution was non-uniform for regions in close vicinity of the source, especially in the high source steps, but for most points at distances >10 mm from the center of the source, the dose distribution was uniform. For most points, the dose uniformity increased with reduction of the source steps and increments of the transverse distance from the source. The dose non-uniformity was similar for most of the corresponding points of 60Co and 192Ir sources with the same treatment lengths and source steps, except at the distance of 150 mm. When using stepping technique for the treatment of tumors, more attention should be focused on treatment planning, especially with higher stepping distances and lower transverse distances from the source.

  18. On the use of particle filters for electromagnetic tracking in high dose rate brachytherapy

    Science.gov (United States)

    Götz, Th I.; Lahmer, G.; Brandt, T.; Kallis, K.; Strnad, V.; Bert, Ch; Hensel, B.; Tomé, A. M.; Lang, E. W.

    2017-10-01

    Modern radiotherapy of female breast cancers often employs high dose rate brachytherapy, where a radioactive source is moved inside catheters, implanted in the female breast, according to a prescribed treatment plan. Source localization relative to the patient’s anatomy is determined with solenoid sensors whose spatial positions are measured with an electromagnetic tracking system. Precise sensor dwell position determination is of utmost importance to assure irradiation of the cancerous tissue according to the treatment plan. We present a hybrid data analysis system which combines multi-dimensional scaling with particle filters to precisely determine sensor dwell positions in the catheters during subsequent radiation treatment sessions. Both techniques are complemented with empirical mode decomposition for the removal of superimposed breathing artifacts. We show that the hybrid model robustly and reliably determines the spatial positions of all catheters used during the treatment and precisely determines any deviations of actual sensor dwell positions from the treatment plan. The hybrid system only relies on sensor positions measured with an EMT system and relates them to the spatial positions of the implanted catheters as initially determined with a computed x-ray tomography.

  19. Hypofractionated high-dose-rate plesiotherapy in nonmelanoma skin cancer treatment.

    Science.gov (United States)

    Arenas, Meritxell; Arguís, Monica; Díez-Presa, Lorena; Henríquez, Ivan; Murcia-Mejía, Mauricio; Gascón, Marina; Gómez, David; Lafuerza, Anna; Mur, Encarna; Azón, Antoni; Rovirosa, Àngels; Sabater, Sebastià

    2015-01-01

    Nonmelanoma skin cancer (NMSC) is the commonest cancer in humans. NMSC treatment currently includes surgery, radiation therapy, and topical approaches. The objective was to analyze and compare the outcomes, toxicity, and cosmesis of NMSC treated by two hypofractionated high-dose-rate (HDR) plesiotherapy techniques. A retrospective institutional clinical study of 134 basal cell or squamous cell skin carcinomas treated at Radiation Oncology Department. Lesions were treated from November 2006 to December 2011 with a moderate hypofractionated HDR plesiotherapy using a fixed applicator or a customized mold. After a median follow-up of 33 months, overall disease-free survival at 3 and 5 years was 95.12% and 93.36%, respectively. For Leipzig applicator, disease-free survival at 3 years was 94.9% and 94.9% at 5 years, for customized mold was 93.1% at 3 years and 88% at 5 years. Complete regression was achieved in 98% of lesions. Two lesions persisted after treatment; both had been treated by a Leipzig applicator. Six lesions suffered local recurrence (five Leipzig applicators and three molds, p = 0.404). Grade skin toxicity. The cosmesis outcomes were excellent or good in 82% of patients, fair in 13%, and not available in 5%. Hypofractionated HDR plesiotherapy is an effective and well-tolerated treatment for NMSC with different toxicity levels depending on the plesiotherapy technique used. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  20. A dose verification method for high-dose-rate brachytherapy treatment plans.

    Science.gov (United States)

    Kumar, Rajesh; Sharma, S D; Vijaykumar, C; Deshpande, Sudesh; Sharma, P K; Vandana, S; Philomena, A; Chilkulwar, Ravi H

    2008-01-01

    To evolve a fast dose verification method for high-dose-rate (HDR) brachytherapy treatment plans and to demonstrate its applicability in different clinical cases. We developed a software tool in VC++ for the Varisource HDR unit for HDR dosimetry plan verification using TG-43 parameters. HDR treatment dosimetry of a number clinical cases using Varisource was verified by comparison with the treatment planning system (TPS). A number of different types of clinical cases treated by Varisource were evaluated. TPS calculated dose values and verification code calculated dose values were found to agree to within 3% for most of the dose calculation points. We have validated with clinical cases a fast and independent dose verification method of the dosimetry at selected points for HDR brachytherapy treatments plan using TG-43 parameters. This can be used for the verification of the TPS calculated dose at various points. The code is written to work with Varisource, but it can conceivably be modified for other sources also by using the fitted constant of the respective source.

  1. Current situation of high-dose-rate brachytherapy for cervical cancer in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Rogerio Matias Vidal da; Souza, Divanizia do Nascimento, E-mail: rmv.fisica@gmail.com [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil); Pinezi, Juliana Castro Dourado [Pontificia Universidade Catolica de Goias (PUC-Goias), Goiania, GO (Brazil); Macedo, Luiz Eduardo Andrade [Hospital Chama, Arapiraca, AL (Brazil)

    2014-05-15

    To assess the current situation of high-dose-rate (HDR) brachytherapy for cancer of the cervix in Brazil, regarding apparatuses, planning methods, prescription, fractionation schedule and evaluation of dose in organs at risk. Materials and methods: in the period between March/2012 and May/2013, a multiple choice questionnaire was developed and sent to 89 Brazilian hospitals which perform HDR brachytherapy. Results: sixty-one services answered the questionnaire. All regions of the country experienced a sharp increase in the number of HDR brachytherapy services in the period from 2001 to 2013. As regards planning, although a three-dimensional planning software was available in 91% of the centers, conventional radiography was mentioned by 92% of the respondents as their routine imaging method for such a purpose. Approximately 35% of respondents said that brachytherapy sessions are performed after teletherapy. The scheme of four 7 Gy intracavitary insertions was mentioned as the most frequently practiced. Conclusion: the authors observed that professionals have difficulty accessing adjuvant three-dimensional planning tools such as computed tomography and magnetic resonance imaging. (author)

  2. Preoperative high dose rate brachytherapy for clinical stage II endometrial carcinoma

    Directory of Open Access Journals (Sweden)

    Alexander Olawaiye

    2011-07-01

    Full Text Available Purpose: We sought to evaluate pathological response, tolerance, and outcome after preoperative (neoadjuvant high dose rate brachytherapy in a small series of patients with clinical stage II endometrial carcinoma, and to evaluate a dose and fractionation protocol for this treatment. Material and methods: Twelve women diagnosed with clinical stage II endometrial carcinoma from 1999-2010 were treated with preoperative radiation therapy. Their medical charts were retrospectively analyzed for HDR treatment regimen, pathological response, and longitudinal outcomes. Radiation doses were normalized to a biologically equi­valent dose of 2 Gy per fraction (EQD2. Results: Two patients had complete pathological response to neoadjuvant therapy; five more had only microscopic residual disease at the time of surgery. At a median follow up of 37 months (1-91 months, one patient has developed recurrence at the vaginal apex six months after completing initial therapy, while another developed a lung recurrence at 28 months. Two-year disease-free and cause-specific survivals were 88% and 100%, respectively. Conclusions: Our small study shows that the HDR fractionation schedule, as done in our series for preoperative radiation therapy for clinical stage II endometrial cancer, is well tolerated and would be an option for patients treated with neoadjuvant radiation therapy.

  3. Monte Carlo dose calculations for high-dose-rate brachytherapy using GPU-accelerated processing.

    Science.gov (United States)

    Tian, Z; Zhang, M; Hrycushko, B; Albuquerque, K; Jiang, S B; Jia, X

    2016-01-01

    Current clinical brachytherapy dose calculations are typically based on the Association of American Physicists in Medicine Task Group report 43 (TG-43) guidelines, which approximate patient geometry as an infinitely large water phantom. This ignores patient and applicator geometries and heterogeneities, causing dosimetric errors. Although Monte Carlo (MC) dose calculation is commonly recognized as the most accurate method, its associated long computational time is a major bottleneck for routine clinical applications. This article presents our recent developments of a fast MC dose calculation package for high-dose-rate (HDR) brachytherapy, gBMC, built on a graphics processing unit (GPU) platform. gBMC-simulated photon transport in voxelized geometry with physics in (192)Ir HDR brachytherapy energy range considered. A phase-space file was used as a source model. GPU-based parallel computation was used to simultaneously transport multiple photons, one on a GPU thread. We validated gBMC by comparing the dose calculation results in water with that computed TG-43. We also studied heterogeneous phantom cases and a patient case and compared gBMC results with Acuros BV results. Radial dose function in water calculated by gBMC showed GPU-based MC dose calculation package, gBMC, for HDR brachytherapy make it attractive for clinical applications. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  4. Verification of High Dose Rate 192Ir Source Position During Brachytherapy Treatment Using Silicon Pixel Detectors

    Science.gov (United States)

    Batic, Matej; Burger, Janez; Cindro, Vladimir; Kramberger, Gregor; Mandic, Igor; Mikuz, Marko; Studen, Andrej; Zavrtanik, Marko

    2011-10-01

    A system for in-vivo tracking of 192Ir source during high dose rate or pulsed dose rate brachytherapy treatment was built using 1 mm thick silicon pad detectors as image sensors and knife-edge lead pinholes as collimators. With source self-images obtained from a dual-pinhole system, location of the source could be reconstructed in three dimensions in real time. The system was tested with 192Ir clinical source (kerma rate in air at 1 m 2.38 Gy/h) in air and plexi-glass phantom. The locations of the source were tracked from a distance of 40 cm in a field of view of 20 × 20 × 20 cm3. Reconstruction precision, defined as the average distance between true and reconstructed source positions, with data collected in less than 1 s with 22 GBq 192Ir source was about 5 mm. The reconstruction precision was in our case mainly limited by imperfect alignment of detectors and pinholes. With perfect alignment the statistical error would allow precision of about 1 mm which could further be improved with larger detector placed at larger distance from the pinhole. However already the modest precision of few millimeters is sufficient for in-vivo detection of larger deviations from planned treatment caused by various misadministrations or malfunctioning of the brachytherapy treatment apparatus. Usage of silicon detectors offers a possibility for building a compact device which could be used as an independent online quality assurance system. In this paper details about sensors, readout system and reconstruction algorithm are described. Results from measurements with clinical source are presented.

  5. Monte Carlo Dosimetry of the 60Co BEBIG High Dose Rate for Brachytherapy.

    Directory of Open Access Journals (Sweden)

    Luciana Tourinho Campos

    Full Text Available The use of high-dose-rate brachytherapy is currently a widespread practice worldwide. The most common isotope source is 192Ir, but 60Co is also becoming available for HDR. One of main advantages of 60Co compared to 192Ir is the economic and practical benefit because of its longer half-live, which is 5.27 years. Recently, Eckert & Ziegler BEBIG, Germany, introduced a new afterloading brachytherapy machine (MultiSource®; it has the option to use either the 60Co or 192Ir HDR source. The source for the Monte Carlo calculations is the new 60Co source (model Co0.A86, which is referred to as the new BEBIG 60Co HDR source and is a modified version of the 60Co source (model GK60M21, which is also from BEBIG.The purpose of this work is to obtain the dosimetry parameters in accordance with the AAPM TG-43U1 formalism with Monte Carlo calculations regarding the BEBIG 60Co high-dose-rate brachytherapy to investigate the required treatment-planning parameters. The geometric design and material details of the source was provided by the manufacturer and was used to define the Monte Carlo geometry. To validate the source geometry, a few dosimetry parameters had to be calculated according to the AAPM TG-43U1 formalism. The dosimetry studies included the calculation of the air kerma strength Sk, collision kerma in water along the transverse axis with an unbounded phantom, dose rate constant and radial dose function. The Monte Carlo code system that was used was EGSnrc with a new cavity code, which is a part of EGS++ that allows calculating the radial dose function around the source. The spectrum to simulate 60Co was composed of two photon energies, 1.17 and 1.33 MeV. Only the gamma part of the spectrum was used; the contribution of the electrons to the dose is negligible because of the full absorption by the stainless-steel wall around the metallic 60Co. The XCOM photon cross-section library was used in subsequent simulations, and the photoelectric effect, pair

  6. Nationwide, Multicenter, Retrospective Study on High-Dose-Rate Brachytherapy as Monotherapy for Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Yoshioka, Yasuo, E-mail: yoshioka@radonc.med.osaka-u.ac.jp [Department of Radiation Oncology, Osaka University Graduate School of Medicine, Osaka (Japan); Kotsuma, Tadayuki [Department of Radiation Oncology, Osaka National Hospital, Osaka (Japan); Komiya, Akira [Department of Urology, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, Toyama (Japan); Department of Urology, Chiba University Hospital, Chiba (Japan); Kariya, Shinji [Department of Radiology, Kochi Medical School, Kochi (Japan); Konishi, Koji [Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka (Japan); Nonomura, Norio [Department of Urology, Osaka University Graduate School of Medicine, Osaka (Japan); Ogawa, Kazuhiko [Department of Radiation Oncology, Osaka University Graduate School of Medicine, Osaka (Japan); Tanaka, Eiichi [Department of Radiation Oncology, Osaka National Hospital, Osaka (Japan); Nishimura, Kensaku [Department of Urology, Osaka National Hospital, Osaka (Japan); Fujiuchi, Yasuyoshi; Kitamura, Hiroshi [Department of Urology, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, Toyama (Japan); Yamagami, Takuji [Department of Radiology, Kochi Medical School, Kochi (Japan); Yamasaki, Ichiro [Department of Urology, Kochi Medical School, Kochi (Japan); Nishimura, Kazuo [Department of Urology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka (Japan); Teshima, Teruki [Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka (Japan); Nakamura, Katsumasa [Department of Radiation Oncology, Hamamatsu University School of Medicine, Shizuoka (Japan); Itami, Jun [Department of Radiation Oncology, National Cancer Center Hospital, Tokyo (Japan)

    2017-04-01

    Purpose: To present, analyze, and discuss results of a nationwide, multicenter, retrospective study on high-dose-rate brachytherapy (HDR-BT) as monotherapy for low-, intermediate-, and high-risk prostate cancer. Methods and Materials: From 1995 through 2013, 524 patients, 73 (14%) with low-risk, 207 (40%) with intermediate-risk, and 244 (47%) with high-risk prostate cancer, were treated with HDR-BT as monotherapy at 5 institutions in Japan. Dose fractionations were 27 Gy/2 fractions for 69 patients (13%), 45.5 Gy/7 fractions for 168 (32%), 49 Gy/7 fractions for 149 (28%), 54 Gy/9 fractions for 130 (25%), and others for 8 (2%). Of these patients, 156 (30%) did not receive androgen deprivation therapy, and 202 patients (39%) did receive androgen deprivation therapy <1 year, 112 (21%) for 1-3 years, and 54 (10%) for >3 years. Median follow-up time was 5.9 years (range, 0.4-18.1 years), with a minimum of 2 years for surviving patients. Results: After 5 years, respective actuarial rates of no biochemical evidence of disease, overall survival, cause-specific survival, and metastasis-free survival for all patients were 92%, 97%, 99%, and 94%. For low/intermediate/high-risk patients, the 5-year no biochemical evidence of disease rates were 95%/94%/89%, the 5-year overall survival rates were 98%/98%/94%, the 5-year cause-specific survival rates were 98%/100%/98%, and the 5-year metastasis-free survival rates were 98%/95%/90%, respectively. The cumulative incidence of late grade 2 to 3 genitourinary toxicity at 5 years was 19%, and that of late grade 3 was 1%. The corresponding incidences of gastrointestinal toxicity were 3% and 0% (0.2%). No grade 4 or 5 of either type of toxicity was detected. Conclusions: The findings of this nationwide, multicenter, retrospective study demonstrate that HDR-BT as monotherapy was safe and effective for all patients with low-, intermediate-, and high-risk prostate cancer.

  7. High-Dose-Rate Monotherapy: Safe and Effective Brachytherapy for Patients With Localized Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Demanes, D. Jeffrey, E-mail: jdemanes@mednet.ucla.edu [California Endocurietherapy at UCLA, Department of Radiation Oncology, David Geffen School of Medicine of University of California at Los Angeles, Los Angeles, CA (United States); Martinez, Alvaro A.; Ghilezan, Michel [William Beaumont Hospital, Royal Oak, MI (United States); Hill, Dennis R.; Schour, Lionel; Brandt, David [California Endocurietherapy, Oakland, CA (United States); Gustafson, Gary [William Beaumont Hospital, Royal Oak, MI (United States)

    2011-12-01

    Purpose: High-dose-rate (HDR) brachytherapy used as the only treatment (monotherapy) for early prostate cancer is consistent with current concepts in prostate radiobiology, and the dose is reliably delivered in a prospectively defined anatomic distribution that meets all the requirements for safe and effective therapy. We report the disease control and toxicity of HDR monotherapy from California Endocurietherapy (CET) and William Beaumont Hospital (WBH) in low- and intermediate-risk prostate cancer patients. Methods and Materials: There were 298 patients with localized prostate cancer treated with HDR monotherapy between 1996 and 2005. Two biologically equivalent hypofractionation protocols were used. At CET the dose was 42 Gy in six fractions (two implantations 1 week apart) delivered to a computed tomography-defined planning treatment volume. At WBH the dose was 38 Gy in four fractions (one implantation) based on intraoperative transrectal ultrasound real-time treatment planning. The bladder, urethral, and rectal dose constraints were similar. Toxicity was scored with the National Cancer Institute Common Toxicity Criteria for Adverse Events version 3. Results: The median follow-up time was 5.2 years. The median age of the patients was 63 years, and the median value of the pretreatment prostate-specific antigen was 6.0 ng/mL. The 8-year results were 99% local control, 97% biochemical control (nadir +2), 99% distant metastasis-free survival, 99% cause-specific survival, and 95% overall survival. Toxicity was scored per event, meaning that an individual patient with more than one symptom was represented repeatedly in the morbidity data table. Genitourinary toxicity consisted of 10% transient Grade 2 urinary frequency or urgency and 3% Grade 3 episode of urinary retention. Gastrointestinal toxicity was <1%. Conclusions: High disease control rates and low morbidity demonstrate that HDR monotherapy is safe and effective for patients with localized prostate cancer.

  8. Online pretreatment verification of high-dose rate brachytherapy using an imaging panel

    Science.gov (United States)

    Fonseca, Gabriel P.; Podesta, Mark; Bellezzo, Murillo; Van den Bosch, Michiel R.; Lutgens, Ludy; Vanneste, Ben G. L.; Voncken, Robert; Van Limbergen, Evert J.; Reniers, Brigitte; Verhaegen, Frank

    2017-07-01

    Brachytherapy is employed to treat a wide variety of cancers. However, an accurate treatment verification method is currently not available. This study describes a pre-treatment verification system that uses an imaging panel (IP) to verify important aspects of the treatment plan. A detailed modelling of the IP was only possible with an extensive calibration performed using a robotic arm. Irradiations were performed with a high dose rate (HDR) 192Ir source within a water phantom. An empirical fit was applied to measure the distance between the source and the detector so 3D Cartesian coordinates of the dwell positions can be obtained using a single panel. The IP acquires 7.14 fps to verify the dwell times, dwell positions and air kerma strength (Sk). A gynecological applicator was used to create a treatment plan that was registered with a CT image of the water phantom used during the experiments for verification purposes. Errors (shifts, exchanged connections and wrong dwell times) were simulated to verify the proposed verification system. Cartesian source positions (panel measurement plane) have a standard deviation of about 0.02 cm. The measured distance between the source and the panel (z-coordinate) have a standard deviation up to 0.16 cm and maximum absolute error of  ≈0.6 cm if the signal is close to sensitive limit of the panel. The average response of the panel is very linear with Sk. Therefore, Sk measurements can be performed with relatively small errors. The measured dwell times show a maximum error of 0.2 s which is consistent with the acquisition rate of the panel. All simulated errors were clearly identified by the proposed system. The use of IPs is not common in brachytherapy, however, it provides considerable advantages. It was demonstrated that the IP can accurately measure Sk, dwell times and dwell positions.

  9. Salvage high-dose-rate brachytherapy for isolated vaginal recurrence of endometrial cancer.

    Science.gov (United States)

    Baek, Sungjae; Isohashi, Fumiaki; Yamaguchi, Hiroko; Mabuchi, Seiji; Yoshida, Ken; Kotsuma, Tadayuki; Yamazaki, Hideya; Tanaka, Eiichi; Sumida, Iori; Tamari, Keisuke; Otani, Keisuke; Seo, Yuji; Suzuki, Osamu; Yoshioka, Yasuo; Kimura, Tadashi; Ogawa, Kazuhiko

    We have retrospectively analyzed the outcomes of high-dose-rate (HDR) brachytherapy as a salvage therapy for vaginal recurrence of endometrial cancer. From 1997 to 2012, salvage HDR brachytherapy was performed in 43 patients. The median age was 64 years (range, 41-88 years). HDR brachytherapy was performed by interstitial brachytherapy in 34 patients (79%) and by intracavity brachytherapy in nine patients (21%). Seventeen (40%) of the 43 patients were treated with external beam radiotherapy. The median followup period was 58 months (range, 6-179 months). The 5-year overall survival (OS), progression-free survival (PFS), and local control rates (LC) were 84%, 52%, and 78%, respectively. Patients who received brachytherapy with external beam radiotherapy experienced no nodal recurrence (0 of 17 patients), whereas 23% of the patients (6 of 26 patients) who received brachytherapy alone experienced nodal recurrence (p = 0.047). The pathologic grade at the time of initial surgery (G1-2 vs. G3) was found to be a significant prognostic factor for both OS and PFS. The respective 5-year OS was 96% vs. 40% (p brachytherapy vs. intracavity brachytherapy) were significant prognostic factors for LC. The respective 5-year LC was 74% vs. 100% (p = 0.020) and 85% vs. 56% (p = 0.035). HDR brachytherapy is effective and feasible in patients with isolated vaginal recurrence of endometrial cancer. Pathologic grade, age, and modality were significant prognostic factors. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  10. High-dose-rate interstitial brachytherapy for female peri-urethral cancer

    Directory of Open Access Journals (Sweden)

    Daya Nand Sharma

    2016-01-01

    Full Text Available Purpose: Peri-urethral cancer (PUC in females is a rare malignancy. Surgery is not usually contemplated due to associated morbidity. Radiation therapy (RT can be employed in the form of interstitial brachytherapy (IBT alone for early lesions, and external beam radiation therapy (EBRT with or without IBT for advanced lesions. We report our first experience in the literature to evaluate the role of high-dose-rate (HDR IBT in female PUC. Material and methods : Between 2008 and 2013, 10 female patients with PUC (5 primary and 5 recurrent were treated with HDR-IBT with or without EBRT at our center. Size of the lesion ranged from 1.5 cm to 5.0 cm. A 2-3 plane free-hand implant was performed using plastic catheters. The prescribed dose of HDR-IBT was 42 Gy in 14 fractions for brachytherapy alone (5 patients, and 18-21 Gy for the boost along with EBRT (5 patients. Patients were followed up regularly for assessment of disease control and toxicity. Results: At a median follow up of 25 months, six patients were disease free at their last follow up. Four patients developed recurrence: 2 at inguinal nodes, 1 at local site, and 1 at both local as well as inguinal nodes. Moist desquamation was the commonest acute toxicity observed in all 5 patients treated with IBT alone, which healed within 4 weeks’ time. Overall, grade II delayed complication rate was 30%. Conclusions : Though small sample size, the results of our study have shown that HDR-IBT provides good loco-regional control with acceptable toxicity for female PUC.

  11. Radioablation of adrenal gland malignomas with interstitial high-dose-rate brachytherapy. Efficacy and outcome

    Energy Technology Data Exchange (ETDEWEB)

    Mohnike, K. [Universitaetsklinikum Magdeburg A.oe.R., Otto-von-Guericke-Universitaet, Klinik fuer Radiologie und Nuklearmedizin, Magdeburg (Germany); DTZ am Frankfurter Tor, Berlin (Germany); Neumann, K.; Seidensticker, M.; Seidensticker, R.; Pech, M.; Streitparth, T.; Ricke, J. [Universitaetsklinikum Magdeburg A.oe.R., Otto-von-Guericke-Universitaet, Klinik fuer Radiologie und Nuklearmedizin, Magdeburg (Germany); Hass, P.; Gademann, G. [Universitaetsklinikum Magdeburg A.oe.R., Otto-von-Guericke-Universitaet, Klinik fuer Strahlentherapie, Magdeburg (Germany); Klose, S. [Universitaetsklinikum Magdeburg A.oe.R., Otto-von-Guericke-Universitaet, Klinik fuer Nieren- und Hochdruckkrankheiten, Diabetologie und Endokrinologie, Magdeburg (Germany); Garlipp, B.; Benckert, C. [Universitaetsklinikum Magdeburg A.oe.R., Otto-von-Guericke-Universitaet, Klinik fuer Allgemein-, Viszeral- und Gefaesschirurgie, Magdeburg (Germany); Wendler, J.J.; Liehr, U.B.; Schostak, M. [Universitaetsklinikum Magdeburg A.oe.R., Otto-von-Guericke-Universitaet, Klinik fuer Urologie und Kinderurologie, Magdeburg (Germany); Goeppner, D. [Universitaetsklinikum Magdeburg A.oe.R., Otto-von-Guericke-Universitaet, Klinik fuer Dermatologie, Magdeburg (Germany)

    2017-08-15

    To assess the efficacy, safety, and outcome of image-guided high-dose-rate (HDR) brachytherapy in patients with adrenal gland metastases (AGM). From January 2007 to April 2014, 37 patients (7 female, 30 male; mean age 66.8 years, range 41.5-82.5 years) with AGM from different primary tumors were treated with CT-guided HDR interstitial brachytherapy (iBT). Primary endpoint was local tumor control (LTC). Secondary endpoints were time to untreatable progression (TTUP), time to progression (TTP), overall survival (OS), and safety. In a secondary analysis, risk factors with an influence on survival were identified. The median biological equivalent dose (BED) was 37.4 Gy. Mean LTC after 12 months was 88%; after 24 months this was 74%. According to CTCAE criteria, one grade 3 adverse event occurred. Median OS after first diagnosis of AGM was 18.3 months. Median OS, TTUP, and TTP after iBT treatment were 11.4, 6.6, and 3.5 months, respectively. Uni- and multivariate Cox regression analyses revealed significant influences of synchronous disease, tumor diameter, and the total number of lesions on OS or TTUP or both. Image-guided HDR-iBT is safe and effective. Treatment- and primary tumor-independent features influenced survival of patients with AGM after HDR-iBR treatment. (orig.) [German] Beurteilung der Effektivitaet, Sicherheit und Ergebnisse nach bildgefuehrter High-dose-rate-(HDR-)Brachytherapie bei Patienten mit Nebennierenmetastasen. Von Januar 2007 bis April 2014 wurden 37 Patienten (7 weiblich, 30 maennlich; mittleres Alter 66,8 Jahre, Spanne 41,5-82,5 Jahre) mit Nebennierenmetastasen verschiedener Primarien mit CT-gesteuerter interstitieller HDR-Brachytherapie (iBT) behandelt. Der primaere Endpunkt war die lokale Tumorkontrolle (LTC). Sekundaere Endpunkte umfassten die Zeit bis zum nicht mehr behandelbaren Progress (TTUP), die Zeit bis zum Progress (TTP), das Gesamtueberleben (OS) und die Sicherheit der Methode. In einer sekundaeren Analyse wurden Risikofaktoren

  12. A method for verification of treatment times for high-dose-rate intraluminal brachytherapy treatment

    Directory of Open Access Journals (Sweden)

    Muhammad Asghar Gadhi

    2016-06-01

    Full Text Available Purpose: This study was aimed to increase the quality of high dose rate (HDR intraluminal brachytherapy treatment. For this purpose, an easy, fast and accurate patient-specific quality assurance (QA tool has been developed. This tool has been implemented at Bahawalpur Institute of Nuclear Medicine and Oncology (BINO, Bahawalpur, Pakistan.Methods: ABACUS 3.1 Treatment planning system (TPS has been used for treatment planning and calculation of total dwell time and then results were compared with the time calculated using the proposed method. This method has been used to verify the total dwell time for different rectum applicators for relevant treatment lengths (2-7 cm and depths (1.5-2.5 cm, different oesophagus applicators of relevant treatment lengths (6-10 cm and depths (0.9 & 1.0 cm, and a bronchus applicator for relevant treatment lengths (4-7.5 cm and depth (0.5 cm.Results: The average percentage differences between treatment time TM with manual calculation and as calculated by the TPS is 0.32% (standard deviation 1.32% for rectum, 0.24% (standard deviation 2.36% for oesophagus and 1.96% (standard deviation 0.55% for bronchus, respectively. These results advocate that the proposed method is valuable for independent verification of patient-specific treatment planning QA.Conclusion: The technique illustrated in the current study is an easy, simple, quick and useful for independent verification of the total dwell time for HDR intraluminal brachytherapy. Our method is able to identify human error-related planning mistakes and to evaluate the quality of treatment planning. It enhances the quality of brachytherapy treatment and reliability of the system.

  13. Comparison of dose and catheter optimization algorithms in prostate high-dose-rate brachytherapy.

    Science.gov (United States)

    Poulin, Eric; Varfalvy, Nicolas; Aubin, Sylviane; Beaulieu, Luc

    2016-01-01

    The purpose of this work was to compare the hybrid inverse treatment planning optimization (HIPO), inverse dose-volume histogram-based optimization (DVHO), and fast simulated annealing stochastic algorithm (IPSA). The catheter optimization algorithm HIPO was also compared with the Centroidal Voronoi Tessellation (CVT) algorithm. In this study, eight high-dose-rate prostate cases were randomly selected from an anonymized bank of patients. Oncentra Prostate v4.1 was used to run DVHO and the HIPO catheter optimization (HIPO_cat), whereas Oncentra Brachy v4.3 was used for the remaining. For fixed catheter configurations, DVHO plans were compared with IPSA and HIPO. For catheter positions optimization, CVT and HIPO_cat algorithms were compared with standard clinical template plans. CVT catheters were further restrained to the template grid (CVT_grid) and compared with HIPO_cat. For dose optimization, IPSA and HIPO were not different from each other. The urethra D10 and the computation time were found significantly better with IPSA and HIPO compared with DVHO (p 0.05). For catheter placement, CVT plans were better, whereas HIPO_cat plans were significantly worse (p HIPO_cat plans do not for all catheter numbers. The CVT algorithm run time was significantly faster than HIPO_cat (p HIPO give similar dosimetric results. The CVT approach was found to be better than HIPO_cat and was able to reduce the number of catheters significantly. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  14. Automated high-dose rate brachytherapy treatment planning for a single-channel vaginal cylinder applicator

    Science.gov (United States)

    Zhou, Yuhong; Klages, Peter; Tan, Jun; Chi, Yujie; Stojadinovic, Strahinja; Yang, Ming; Hrycushko, Brian; Medin, Paul; Pompos, Arnold; Jiang, Steve; Albuquerque, Kevin; Jia, Xun

    2017-06-01

    High dose rate (HDR) brachytherapy treatment planning is conventionally performed manually and/or with aids of preplanned templates. In general, the standard of care would be elevated by conducting an automated process to improve treatment planning efficiency, eliminate human error, and reduce plan quality variations. Thus, our group is developing AutoBrachy, an automated HDR brachytherapy planning suite of modules used to augment a clinical treatment planning system. This paper describes our proof-of-concept module for vaginal cylinder HDR planning that has been fully developed. After a patient CT scan is acquired, the cylinder applicator is automatically segmented using image-processing techniques. The target CTV is generated based on physician-specified treatment depth and length. Locations of the dose calculation point, apex point and vaginal surface point, as well as the central applicator channel coordinates, and the corresponding dwell positions are determined according to their geometric relationship with the applicator and written to a structure file. Dwell times are computed through iterative quadratic optimization techniques. The planning information is then transferred to the treatment planning system through a DICOM-RT interface. The entire process was tested for nine patients. The AutoBrachy cylindrical applicator module was able to generate treatment plans for these cases with clinical grade quality. Computation times varied between 1 and 3 min on an Intel Xeon CPU E3-1226 v3 processor. All geometric components in the automated treatment plans were generated accurately. The applicator channel tip positions agreed with the manually identified positions with submillimeter deviations and the channel orientations between the plans agreed within less than 1 degree. The automatically generated plans obtained clinically acceptable quality.

  15. Impact of source position on high-dose-rate skin surface applicator dosimetry.

    Science.gov (United States)

    Jeong, Jeho; Barker, Christopher A; Zaider, Marco; Cohen, Gil'ad N

    2016-01-01

    Skin surface dosimetric discrepancies between measured and treatment planning system predicted values were traced to source position sag inside the applicator and to source transit time. We quantified their dosimetric impact and propose corrections for clinical use. We measured the dose profiles from the Varian Leipzig-style high-dose-rate (HDR) skin applicator, using EBT3 film, photon diode, and optically stimulated luminescence dosimeter for three different GammaMedplus HDR afterloaders. The measured dose profiles at several depths were compared with BrachyVision Acuros calculated profiles. To assess the impact of the source sag, two different applicator orientations were considered. The dose contribution during source transit was assessed by comparing diode measurements using an HDR timer and an electrometer timer. Depth doses measured using the three dosimeters were in good agreement, but were consistently higher than the Acuros dose calculations. Measurements with the applicator face up were significantly (exceeding 10%) lower than those in the face down position, due to source sag inside the applicator. Based on the inverse square law, the effective source sag was evaluated to be about 0.5 mm from the planned position. The additional dose during source transit was evaluated to be about 2.8% for 30 seconds of treatment with a 40700 U (10 Ci) source. With a very short source-to-surface distance, the small source sag inside the applicator has a significant dosimetric impact. This effect is unaccounted for in the vendor's treatment planning template and should be considered before the clinical use of the applicator. Further investigation of other applicators with large source lumen diameter may be warranted. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  16. Prostate-Specific Antigen Bounce After High-Dose-Rate Monotherapy for Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Mehta, Niraj H., E-mail: nmehta@mednet.ucla.edu [University of California, Los Angeles, Los Angeles, California (United States); Kamrava, Mitchell; Wang, Pin-Chieh; Steinberg, Michael; Demanes, Jeffrey [University of California, Los Angeles, Los Angeles, California (United States)

    2013-07-15

    Purpose: To characterize the magnitude and kinetics of prostate-specific antigen (PSA) bounces after high-dose-rate (HDR) monotherapy and determine relationships between certain clinical factors and PSA bounce. Methods and Materials: Longitudinal PSA data and various clinical parameters were examined in 157 consecutive patients treated with HDR monotherapy between 1996 and 2005. We used the following definition for PSA bounce: rise in PSA ≥threshold, after which it returns to the prior level or lower. Prostate-specific antigen failure was defined per the Phoenix definition (nadir +2 ng/mL). Results: A PSA bounce was noted in 67 patients (43%). The number of bounces per patient was 1 in 45 cases (67%), 2 in 19 (28%), 3 in 2 (3%), 4 in 0, and 5 in 1 (1%). The median time to maximum PSA bounce was 1.3 years, its median magnitude was 0.7, and its median duration was 0.75 years. Three patients (2%) were noted to have PSA failure. None of the 3 patients who experienced biochemical failure exhibited PSA bounce. In the fully adjusted model for predicting each bounce, patients aged <55 years had a statistically significant higher likelihood of experiencing a bounce (odds ratio 2.22, 95% confidence interval 1.38-3.57, P=.001). There was also a statistically significant higher probability of experiencing a bounce for every unit decrease in Gleason score (odds ratio 1.52, 95% confidence interval 1.01-2.04, P=.045). Conclusions: A PSA bounce occurs in a significant percentage of patients treated with HDR monotherapy, with magnitudes varying from <1 in 28% of cases to ≥1 in 15%. The median duration of bounce is <1 year. More bounces were identified in patients with lower Gleason score and age <55 years. Further investigation using a model to correlate magnitude and frequency of bounces with clinical variables are under way.

  17. An automated optimization tool for high-dose-rate (HDR) prostate brachytherapy with divergent needle pattern

    Science.gov (United States)

    Borot de Battisti, M.; Maenhout, M.; de Senneville, B. Denis; Hautvast, G.; Binnekamp, D.; Lagendijk, J. J. W.; van Vulpen, M.; Moerland, M. A.

    2015-10-01

    Focal high-dose-rate (HDR) for prostate cancer has gained increasing interest as an alternative to whole gland therapy as it may contribute to the reduction of treatment related toxicity. For focal treatment, optimal needle guidance and placement is warranted. This can be achieved under MR guidance. However, MR-guided needle placement is currently not possible due to space restrictions in the closed MR bore. To overcome this problem, a MR-compatible, single-divergent needle-implant robotic device is under development at the University Medical Centre, Utrecht: placed between the legs of the patient inside the MR bore, this robot will tap the needle in a divergent pattern from a single rotation point into the tissue. This rotation point is just beneath the perineal skin to have access to the focal prostate tumor lesion. Currently, there is no treatment planning system commercially available which allows optimization of the dose distribution with such needle arrangement. The aim of this work is to develop an automatic inverse dose planning optimization tool for focal HDR prostate brachytherapy with needle insertions in a divergent configuration. A complete optimizer workflow is proposed which includes the determination of (1) the position of the center of rotation, (2) the needle angulations and (3) the dwell times. Unlike most currently used optimizers, no prior selection or adjustment of input parameters such as minimum or maximum dose or weight coefficients for treatment region and organs at risk is required. To test this optimizer, a planning study was performed on ten patients (treatment volumes ranged from 8.5 cm3to 23.3 cm3) by using 2-14 needle insertions. The total computation time of the optimizer workflow was below 20 min and a clinically acceptable plan was reached on average using only four needle insertions.

  18. Dosimetric impact of interfraction catheter movement in high-dose rate prostate brachytherapy.

    Science.gov (United States)

    Foster, William; Cunha, J Adam M; Hsu, I-Chow; Weinberg, Vivan; Krishnamurthy, Devan; Pouliot, Jean

    2011-05-01

    To evaluate the impact of interfraction catheter movement on dosimetry in prostate high-dose-rate (HDR) brachytherapy. Fifteen patients were treated with fractionated HDR brachytherapy. Implants were performed on day 1 under transrectal ultrasound guidance. A computed tomography (CT) scan was performed. Inverse planning simulated annealing was used for treatment planning. The first fraction was delivered on day 1. A cone beam CT (CBCT) was performed on day 2 before the second fraction was given. A fusion of the CBCT and CT was performed using intraprostatic gold markers as landmarks. Initial prostate and urethra contours were transferred to the CBCT images. Bladder and rectum contours were drawn, and catheters were digitized on the CBCT. The planned treatment was applied to the CBCT dataset, and dosimetry was analyzed and compared to the initial dose distribution. This process was repeated after a reoptimization was performed, using the same constraints used on day 1. Mean interfraction catheter displacement was 5.1 mm. When we used the initial plan on day 2, the mean prostate V100 (volume receiving 100 Gy or more) decreased from 93.8% to 76.2% (p < 0.01). Rectal V75 went from 0.75 cm(3) to 1.49 cm(3) (p < 0.01). A reoptimization resulted in a mean prostate V100 of 88.1%, closer to the initial plan (p = 0.05). Mean rectal V75 was also improved with a value of 0.59 cm(3). There was no significant change in bladder and urethra dose on day 2. A mean interfraction catheter displacement of 5.1 mm results in a significant decrease in prostate V100 and an increase in rectum dose. A reoptimization before the second treatment improves dose distribution. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. 3D-printed surface mould applicator for high-dose-rate brachytherapy

    Science.gov (United States)

    Schumacher, Mark; Lasso, Andras; Cumming, Ian; Rankin, Adam; Falkson, Conrad B.; Schreiner, L. John; Joshi, Chandra; Fichtinger, Gabor

    2015-03-01

    In contemporary high-dose-rate brachytherapy treatment of superficial tumors, catheters are placed in a wax mould. The creation of current wax models is a difficult and time consuming proces.The irradiation plan can only be computed post-construction and requires a second CT scan. In case no satisfactory dose plan can be created, the mould is discarded and the process is repeated. The objective of this work was to develop an automated method to replace suboptimal wax moulding. We developed a method to design and manufacture moulds that guarantee to yield satisfactory dosimetry. A 3D-printed mould with channels for the catheters designed from the patient's CT and mounted on a patient-specific thermoplastic mesh mask. The mould planner was implemented as an open-source module in the 3D Slicer platform. Series of test moulds were created to accommodate standard brachytherapy catheters of 1.70mm diameter. A calibration object was used to conclude that tunnels with a diameter of 2.25mm, minimum 12mm radius of curvature, and 1.0mm open channel gave the best fit for this printer/catheter combination. Moulds were created from the CT scan of thermoplastic mesh masks of actual patients. The patient-specific moulds have been visually verified to fit on the thermoplastic meshes. The masks were visually shown to fit onto the thermoplastic meshes, next the resulting dosimetry will have to be compared with treatment plans and dosimetry achieved with conventional wax moulds in order to validate our 3D printed moulds.

  20. Dosimetric verification of a high dose rate brachytherapy treatment planning system in homogeneous and heterogeneous media.

    Science.gov (United States)

    Uniyal, S C; Sharma, S D; Naithani, U C

    2013-03-01

    To verify the dosimetric accuracy of treatment plans in high dose rate (HDR) brachytherapy by using Gafchromic EBT2 film and to demonstrate the adequacy of dose calculations of a commercial treatment planning system (TPS) in a heterogeneous medium. Absorbed doses at chosen points in anatomically different tissue equivalent phantoms were measured using Gafchromic EBT2 film. In one case, tandem ovoid brachytherapy was performed in a homogeneous cervix phantom, whereas in the other, organ heterogeneities were introduced in a phantom to replicate the upper thorax for esophageal brachytherapy treatment. A commercially available TPS was used to perform treatment planning in each case and the EBT2 films were irradiated with the HDR Ir-192 brachytherapy source. Film measurements in the cervix phantom were found to agree with the TPS calculated values within 3% in the clinically relevant volume. In the thorax phantom, the presence of surrounding heterogeneities was not seen to affect the dose distribution in the volume being treated, whereas, a little dose perturbation was observed at the lung surface. Doses to the spinal cord and to the sternum bone were overestimated and underestimated by 14.6% and 16.5% respectively by the TPS relative to the film measurements. At the trachea wall facing the esophagus, a dose reduction of 10% was noticed in the measurements. The dose calculation accuracy of the TPS was confirmed in homogeneous medium, whereas, it was proved inadequate to produce correct dosimetric results in conditions of tissue heterogeneity. Copyright © 2012 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  1. Custom-made micro applicators for high-dose-rate brachytherapy treatment of chronic psoriasis

    Directory of Open Access Journals (Sweden)

    Ivan M. Buzurovic

    2017-06-01

    Full Text Available Purpose: In this study, we present the treatment of the psoriatic nail beds of patients refractory to standard therapies using high-dose-rate (HDR brachytherapy. The custom-made micro applicators (CMMA were designed and constructed for radiation dose delivery to small curvy targets with complicated topology. The role of the HDR brachytherapy treatment was to stimulate the T cells for an increased immune response. Material and methods: The patient diagnosed with psoriatic nail beds refractory to standard therapies received monthly subunguinal injections that caused significant pain and discomfort in both hands. The clinical target was defined as the length from the fingertip to the distal interphalangeal joint. For the accurate and reproducible setup in the multi-fractional treatment delivery, the CMMAs were designed. Five needles were embedded into the dense plastic mesh and covered with 5 mm bolus material for each micro applicator. Five CMMAs were designed, resulting in the usage of 25 catheters in total. Results: The prescription dose was planned to the depth of the anterior surface of the distal phalanx, allowing for the sparing of the surrounding tissue. The total number of the active dwell positions was 145 with step size of 5 mm. The total treatment time was 115 seconds with a 7.36 Ci activity of the 192Ir source. The treatment resulted in good pain control. The patient did not require further injections to the nail bed. After this initial treatment, additional two patients with similar symptoms received HDR brachytherapy. The treatment outcome was favorable in all cases. Conclusions : The first HDR brachytherapy treatment of psoriasis of the nail bed is presented. The initial experience revealed that brachytherapy treatment was well-tolerated and resulted in adequate control of the disease. A larger cohort of patients will be required for additional conclusions related to the long-term clinical benefits.

  2. Second salvage high-dose-rate brachytherapy for radiorecurrent prostate cancer

    Directory of Open Access Journals (Sweden)

    Metha Maenhout

    2017-04-01

    Full Text Available Purpose : Salvage treatments for localized radiorecurrent prostate cancer can be performed safely when a focal and image guided approach is used. Due to the low toxicity, the opportunity exists to investigate a second salvage treatment when a second locally recurrent prostate cancer occurs. Here, we describe a second salvage treatment procedure of 4 patients. Material and methods : Four patients with a pathologically proven second local recurrence were treated in an outpatient magnetic resonance imaging (MRI-guided setting with a single fraction of 19 Gy focal high-dose-rate brachytherapy (HDR-BT. Delineation was performed using choline-PET-CT or a 68Ga-PSMA PET in combination with multiparametric 3 Tesla MRI in all four patients. Toxicity was measured using common toxicity criteria for adverse events (CTCAE version 4.0. Results : With a median follow-up of 12 months (range, 6-15, there were 2 patients with biochemical recurrence as defined by the Phoenix-definition. There were no patients with grade 3 or more toxicity. In all second salvage HDR-BT treatments, the constraints for rectum, bladder, and urethra were met. Median treatment volume (GTV was 4.8 cc (range, 1.9-6.6 cc. A median of 8 catheters (range, 6-9 were used, and the median dose to the treatment volume (GTV was a D95: 19.3 Gy (SD 15.5-19.4 Gy. Conclusions : Second focal salvage MRI-guided HDR-BT for a select group of patients with a second locally recurrent prostate cancer is feasible. There was no grade 3 or more acute toxicity for these four patients.

  3. Clinical implementation of a novel applicator in high-dose-rate brachytherapy treatment of esophageal cancer

    Directory of Open Access Journals (Sweden)

    Ivan M. Buzurovic

    2016-08-01

    Full Text Available Purpose : In this study, we present the clinical implementation of a novel transoral balloon centering esophageal applicator (BCEA and the initial clinical experience in high-dose-rate (HDR brachytherapy treatment of esophageal cancer, using this applicator. Material and methods: Acceptance testing and commissioning of the BCEA were performed prior to clinical use. Full performance testing was conducted including measurements of the dimensions and the catheter diameter, evaluation of the inflatable balloon consistency, visibility of the radio-opaque markers, congruence of the markers, absolute and relative accuracy of the HDR source in the applicator using the radiochromic film and source position simulator, visibility and digitization of the applicator on the computed tomography (CT images under the clinical conditions, and reproducibility of the offset. Clinical placement of the applicator, treatment planning, treatment delivery, and patient’s response to the treatment were elaborated as well. Results : The experiments showed sub-millimeter accuracy in the source positioning with distal position at 1270 mm. The digitization (catheter reconstruction was uncomplicated due to the good visibility of markers. The treatment planning resulted in a favorable dose distribution. This finding was pronounced for the treatment of the curvy anatomy of the lesion due to the improved repeatability and consistency of the delivered fractional dose to the patient, since the radioactive source was placed centrally within the lumen with respect to the clinical target due to the five inflatable balloons. Conclusions : The consistency of the BCEA positioning resulted in the possibility to deliver optimized non-uniform dose along the catheter, which resulted in an increase of the dose to the cancerous tissue and lower doses to healthy tissue. A larger number of patients and long-term follow-up will be required to investigate if the delivered optimized treatment can

  4. High-dose-rate brachytherapy for uterine cervical cancer: the results of different fractionation regimen

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Won Sup; Kim, Tae Hyun; Yang, Dae Sik; Choi, Myung Sun; Kim, Chul Yong [College of Medicine, Korea University, Seoul (Korea, Republic of)

    2002-09-15

    Although high-dose-rate (HDR) brachytherapy regimens have been practiced with a variety of modalities and various degrees of success, few studies on the subject have been conducted. The purpose of this study was to compare the results of local control and late complication rate according to different HDR brachytherapy fractionation regimens in uterine cervical cancer patients. From November 1992 to March 1998, 224 patients with uterine cervical cancer were treated with external beam irradiation and HDR brachytherapy. In external pelvic radiation therapy, the radiation dose was 45 {approx} 54 Gy (median dose 54 Gy) with daily fraction size 1.8 Gy, five times per week. In HDR brachytherapy, 122 patients (Group A) were treated with three times weekly with 3 Gy to line-A (isodose line of 2 cm radius from source) and 102 patients (Group B) underwent the HDR brachytherapy twice weekly with 4 or 4.5 Gy to line-A after external beam irradiation. Iridium-192 was used as the source of HDR brachytherapy. Late complication was assessed from grade 1 to 5 using the RTOG morbidity grading system. The local control rate (LCR) at 5 years was 80% in group A and 84% in group B ({rho} = 0.4523). In the patients treated with radiation therapy alone, LCR at 5 years was 60.9% in group A and 76.9% in group B ({rho} = 0.2557). In post-operative radiation therapy patients, LCR at 5 years was 92.6% in group A and 91.6% in group B ({rho} 0.8867). The incidence of late complication was 18% (22 patients) and 29.4% (30 patients), of bladder complication was 9.8% (12 patients) and 14.7% (15 patients), and of rectal complication was 9.8% (12 patients) and 21.6% (22 patients), in group A and B, respectively. Lower fraction sized HDR brachytherapy was associated with decrease in late complication ({rho} =0.0405) (rectal complication, {rho} = 0.0147; bladder complication, {rho} =0.115). The same result was observed in postoperative radiation therapy patients ({rho} = 0.0860) and radiation only

  5. Inverse Planned High-Dose-Rate Brachytherapy for Locoregionally Advanced Cervical Cancer: 4-Year Outcomes

    Energy Technology Data Exchange (ETDEWEB)

    Tinkle, Christopher L.; Weinberg, Vivian [Department of Radiation Oncology, University of California, San Francisco, California (United States); Chen, Lee-May [Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Francisco, California (United States); Littell, Ramey [Gynecologic Oncology, The Permanente Medical Group, San Francisco, California (United States); Cunha, J. Adam M.; Sethi, Rajni A. [Department of Radiation Oncology, University of California, San Francisco, California (United States); Chan, John K. [Gynecologic Oncology, California Pacific Medical Center, San Francisco, California (United States); Hsu, I-Chow, E-mail: ichow.hsu@ucsf.edu [Department of Radiation Oncology, University of California, San Francisco, California (United States)

    2015-08-01

    Purpose: Evaluate the efficacy and toxicity of image guided brachytherapy using inverse planning simulated annealing (IPSA) high-dose-rate brachytherapy (HDRB) boost for locoregionally advanced cervical cancer. Methods and Materials: From December 2003 through September 2009, 111 patients with primary cervical cancer were treated definitively with IPSA-planned HDRB boost (28 Gy in 4 fractions) after external radiation at our institution. We performed a retrospective review of our experience using image guided brachytherapy. Of the patients, 70% had a tumor size >4 cm, 38% had regional nodal disease, and 15% had clinically evident distant metastasis, including nonregional nodal disease, at the time of diagnosis. Surgical staging involving pelvic lymph node dissection was performed in 15% of patients, and 93% received concurrent cisplatin-based chemotherapy. Toxicities are reported according to the Common Terminology Criteria for Adverse Events version 4.0 guidelines. Results: With a median follow-up time of 42 months (range, 3-84 months), no acute or late toxicities of grade 4 or higher were observed, and grade 3 toxicities (both acute and late) developed in 8 patients (1 constitutional, 1 hematologic, 2 genitourinary, 4 gastrointestinal). The 4-year Kaplan-Meier estimate of late grade 3 toxicity was 8%. Local recurrence developed in 5 patients (4 to 9 months after HDRB), regional recurrence in 3 (6, 16, and 72 months after HDRB), and locoregional recurrence in 1 (4 months after HDR boost). The 4-year estimates of local, locoregional, and distant control of disease were 94.0%, 91.9%, and 69.1%, respectively. The overall and disease-free survival rates at 4 years were 64.3% (95% confidence interval [CI] of 54%-73%) and 61.0% (95% CI, 51%-70%), respectively. Conclusions: Definitive radiation by use of inverse planned HDRB boost for locoregionally advanced cervical cancer is well tolerated and achieves excellent local control of disease. However, overall

  6. Limitations of the TG-43 formalism for skin high-dose-rate brachytherapy dose calculations

    Energy Technology Data Exchange (ETDEWEB)

    Granero, Domingo, E-mail: dgranero@eresa.com [Department of Radiation Physics, ERESA, Hospital General Universitario, 46014 Valencia (Spain); Perez-Calatayud, Jose [Radiotherapy Department, La Fe University and Polytechnic Hospital, Valencia 46026 (Spain); Vijande, Javier [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100, Spain and IFIC (UV-CSIC), Paterna 46980 (Spain); Ballester, Facundo [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100 (Spain); Rivard, Mark J. [Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts 02111 (United States)

    2014-02-15

    Purpose: In skin high-dose-rate (HDR) brachytherapy, sources are located outside, in contact with, or implanted at some depth below the skin surface. Most treatment planning systems use the TG-43 formalism, which is based on single-source dose superposition within an infinite water medium without accounting for the true geometry in which conditions for scattered radiation are altered by the presence of air. The purpose of this study is to evaluate the dosimetric limitations of the TG-43 formalism in HDR skin brachytherapy and the potential clinical impact. Methods: Dose rate distributions of typical configurations used in skin brachytherapy were obtained: a 5 cm × 5 cm superficial mould; a source inside a catheter located at the skin surface with and without backscatter bolus; and a typical interstitial implant consisting of an HDR source in a catheter located at a depth of 0.5 cm. Commercially available HDR{sup 60}Co and {sup 192}Ir sources and a hypothetical {sup 169}Yb source were considered. The Geant4 Monte Carlo radiation transport code was used to estimate dose rate distributions for the configurations considered. These results were then compared to those obtained with the TG-43 dose calculation formalism. In particular, the influence of adding bolus material over the implant was studied. Results: For a 5 cm × 5 cm{sup 192}Ir superficial mould and 0.5 cm prescription depth, dose differences in comparison to the TG-43 method were about −3%. When the source was positioned at the skin surface, dose differences were smaller than −1% for {sup 60}Co and {sup 192}Ir, yet −3% for {sup 169}Yb. For the interstitial implant, dose differences at the skin surface were −7% for {sup 60}Co, −0.6% for {sup 192}Ir, and −2.5% for {sup 169}Yb. Conclusions: This study indicates the following: (i) for the superficial mould, no bolus is needed; (ii) when the source is in contact with the skin surface, no bolus is needed for either {sup 60}Co and {sup 192}Ir. For

  7. Biological effective doses in the intracavitary high dose rate brachytherapy of cervical cancer

    Directory of Open Access Journals (Sweden)

    Y. Sobita Devi

    2011-12-01

    Full Text Available Purpose: The aim of this study is to evaluate the decrease of biological equivalent dose and its correlation withlocal/loco-regional control of tumour in the treatment of cervical cancer when the strength of the Ir-192 high dose rate(HDR brachytherapy (BT source is reduced to single, double and triple half life in relation to original strength of10 Ci (~ 4.081 cGy x m2 x h–1. Material and methods: A retrospective study was carried out on 52 cervical cancer patients with stage II and IIItreated with fractionated HDR-BT following external beam radiation therapy (EBRT. International Commission onRadiation Units and Measurement (ICRU points were defined according to ICRU Report 38, using two orthogonal radiographimages taken by Simulator (Simulix HQ. Biologically effective dose (BED was calculated at point A for diffe -rent Ir-192 source strength and its possible correlation with local/loco-regional tumour control was discussed. Result: The increase of treatment time per fraction of dose due to the fall of dose rate especially in HDR-BT of cervicalcancer results in reduction in BED of 2.59%, 7.02% and 13.68% with single, double and triple half life reduction ofsource strength, respectively. The probabilities of disease recurrence (local/loco-regional within 26 months are expectedas 0.12, 0.12, 0.16, 0.39 and 0.80 for source strength of 4.081, 2.041, 1.020, 0.510 and 0.347 cGy x m2 x h–1, respectively.The percentages of dose increase required to maintain the same BED with respect to initial BED were estimated as1.71, 5.00, 11.00 and 15.86 for the dose rate of 24.7, 12.4, 6.2 and 4.2 Gy/hr at point A, respectively. Conclusions: This retrospective study of cervical cancer patients treated with HDR-BT at different Ir-192 sourcestrength shows reduction in disease free survival according to the increase in treatment time duration per fraction.The probable result could be associated with the decrease of biological equivalent dose to point A. Clinical

  8. Limitations of the TG-43 formalism for skin high-dose-rate brachytherapy dose calculations.

    Science.gov (United States)

    Granero, Domingo; Perez-Calatayud, Jose; Vijande, Javier; Ballester, Facundo; Rivard, Mark J

    2014-02-01

    In skin high-dose-rate (HDR) brachytherapy, sources are located outside, in contact with, or implanted at some depth below the skin surface. Most treatment planning systems use the TG-43 formalism, which is based on single-source dose superposition within an infinite water medium without accounting for the true geometry in which conditions for scattered radiation are altered by the presence of air. The purpose of this study is to evaluate the dosimetric limitations of the TG-43 formalism in HDR skin brachytherapy and the potential clinical impact. Dose rate distributions of typical configurations used in skin brachytherapy were obtained: a 5 cm × 5 cm superficial mould; a source inside a catheter located at the skin surface with and without backscatter bolus; and a typical interstitial implant consisting of an HDR source in a catheter located at a depth of 0.5 cm. Commercially available HDR(60)Co and (192)Ir sources and a hypothetical (169)Yb source were considered. The Geant4 Monte Carlo radiation transport code was used to estimate dose rate distributions for the configurations considered. These results were then compared to those obtained with the TG-43 dose calculation formalism. In particular, the influence of adding bolus material over the implant was studied. For a 5 cm × 5 cm(192)Ir superficial mould and 0.5 cm prescription depth, dose differences in comparison to the TG-43 method were about -3%. When the source was positioned at the skin surface, dose differences were smaller than -1% for (60)Co and (192)Ir, yet -3% for (169)Yb. For the interstitial implant, dose differences at the skin surface were -7% for (60)Co, -0.6% for (192)Ir, and -2.5% for (169)Yb. This study indicates the following: (i) for the superficial mould, no bolus is needed; (ii) when the source is in contact with the skin surface, no bolus is needed for either (60)Co and (192)Ir. For lower energy radionuclides like (169)Yb, bolus may be needed; and (iii) for the interstitial case, at

  9. Concomitant cervical and transperineal parametrial high-dose-rate brachytherapy boost for locally advanced cervical cancer

    Directory of Open Access Journals (Sweden)

    Caroline Bailleux

    2016-01-01

    Full Text Available Purpose: There is no consensus for parametrial boost technic while both transvaginal and transperineal approaches are discussed. A prototype was developed consisting of a perineal template, allowing transperineal needle insertion. This study analyzed acute toxicity of concomitant cervical and transperineal parametrial high-dose-rate brachytherapy (HDRB boost for locally advanced cervical cancer. Material and methods: From 01.2011 to 12.2014, 33 patients (pts presenting a locally advanced cervical cancer with parametrial invasion were treated. After the first course of external beam radiation therapy with cisplatinum, HDRB was performed combining endocavitary and interstitial technique for cervical and parametrial disease. Post-operative delineation (CTV, bladder, rectum, sigmoid and planification were based on CT-scan/MRI. HDRB was delivered in 3-5 fractions over 2-3 consecutive days. Acute toxicities occurring within 6 months after HDRB were retrospectively reviewed. Results: Median age was 56.4 years (27-79. Clinical stages were: T2b = 23 pts (69.7%, T3a = 1 pt (3%, T3b = 6 pts (18.2%, and T4a = 3 pts (9.1%. Median HDRB prescribed dose was 21 Gy (21-27. Median CTVCT (16 pts and HR-CTV MRI (17 pts were 52.6 cc (28.5-74.3, 31.9 cc (17.1-58, respectively. Median EQD2αβ10 for D90CTV and D90HR-CTV were 82.9 Gy (78.2-96.5, 84.8 Gy (80.6-91.4, respectively. Median EQD2αβ3 (CT/MRI for D2cc bladder, rectum and sigmoid were 75.5 Gy (66.6-90.9, 64.4 Gy (51.9-77.4, and 60.4 Gy (50.9-81.1, respectively. Median follow-up was 14 months (ranged 6-51. Among the 24 pts with MFU = 24 months, 2-year LRFS rate, RRFS, and OS were 86.8%, 88.8%, and 94.1%, respectively. The rates of acute genitourinary and gastrointestinal toxicities were 36% (G1 dysuria = 8 pts, G2 infection = 2 pt, G3 infection = 2 pts, and 27% (G1 diarrhea = 9 pts, respectively. One patient presented vaginal bleeding at the time of applicator withdrawal (G3-blood transfusion; no bleeding was

  10. Predictors of Toxicity After Image-guided High-dose-rate Interstitial Brachytherapy for Gynecologic Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Larissa J. [Department of Radiation Oncology, Brigham and Women' s Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts (United States); Viswanathan, Akila N., E-mail: aviswanathan@lroc.harvard.edu [Department of Radiation Oncology, Brigham and Women' s Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts (United States)

    2012-12-01

    Purpose: To identify predictors of grade 3-4 complications and grade 2-4 rectal toxicity after three-dimensional image-guided high-dose-rate (HDR) interstitial brachytherapy for gynecologic cancer. Methods and Materials: Records were reviewed for 51 women (22 with primary disease and 29 with recurrence) treated with HDR interstitial brachytherapy. A single interstitial insertion was performed with image guidance by computed tomography (n = 43) or magnetic resonance imaging (n = 8). The median delivered dose in equivalent 2-Gy fractions was 72.0 Gy (45 Gy for external-beam radiation therapy and 24 Gy for brachytherapy). Toxicity was reported according to the Common Toxicity Criteria for Adverse Events. Actuarial toxicity estimates were calculated by the Kaplan-Meier method. Results: At diagnosis, the median patient age was 62 years and the median tumor size was 3.8 cm. The median D90 and V100 were 71.4 Gy and 89.5%; the median D2cc for the bladder, rectum, and sigmoid were 64.6 Gy, 61.0 Gy, and 52.7 Gy, respectively. The actuarial rates of all grade 3-4 complications at 2 years were 20% gastrointestinal, 9% vaginal, 6% skin, 3% musculoskeletal, and 2% lymphatic. There were no grade 3-4 genitourinary complications and no grade 5 toxicities. Grade 2-4 rectal toxicity was observed in 10 patients, and grade 3-4 complications in 4; all cases were proctitis with the exception of 1 rectal fistula. D2cc for rectum was higher for patients with grade 2-4 (68 Gy vs 57 Gy for grade 0-1, P=.03) and grade 3-4 (73 Gy vs 58 Gy for grade 0-2, P=.02) rectal toxicity. The estimated dose that resulted in a 10% risk of grade 2-4 rectal toxicity was 61.8 Gy (95% confidence interval, 51.5-72.2 Gy). Discussion: Image-guided HDR interstitial brachytherapy results in acceptable toxicity for women with primary or recurrent gynecologic cancer. D2cc for the rectum is a reliable predictor of late rectal complications. Three-dimensional-based treatment planning should be performed to ensure

  11. High-dose-rate brachytherapy monotherapy without androgen deprivation therapy for intermediate-risk prostate cancer.

    Science.gov (United States)

    Patel, Shyamal; Demanes, D Jeffrey; Ragab, Omar; Zhang, Mingle; Veruttipong, Darlene; Nguyen, Kristine; Park, Sang-June; Marks, Leonard; Pantuck, Allan; Steinberg, Michael; Kamrava, Mitchell

    Outcomes using high-dose-rate (HDR) brachytherapy monotherapy (without androgen deprivation therapy or external beam radiation therapy) for National Comprehensive Cancer Network-defined intermediate-risk (IR) patients are limited. We report our long-term data using HDR monotherapy for this patient population. One-hundred ninety IR prostate cancer patients were treated 1996-2013 with HDR monotherapy. Biochemical prostate-specific antigen (PSA) failure was per the Phoenix definition. Acute and late genitourinary and gastrointestinal toxicities were graded according to Common Toxicity Criteria of Adverse Events, version 4. Kaplan-Meier (KM) biochemical progression-free survival (BPFS), cause-specific survival, and overall survival rates were calculated. Univariate analyses were performed to determine relationships with BPFS. The median patient age was 66 years (43-90), and the median initial PSA was 7.4 ng/mL. The Gleason score was ≤6 in 26%, 3 + 4 in 62%, and 4 + 3 in 12%. The median treatment BED1.5 was 254 Gy; 83% of patients were treated with a dose of 7.25 Gy × six fractions delivered in two separate implants. With a median follow-up of 6.2 years, KM BPFS at 5/8 years was 97%/90%, cause-specific survival at 8 years was 100%, and overall survival at 5/8 years was 93%/88%. Late genitourinary toxicities were 36.3% Grade 1, 18.9% Grade 2, and 3.7% Grade 3. Late gastrointestinal toxicities were 6.3% Grade 1, 1.1% Grade 2, and no Grade ≥3. Of the patients with no sexual dysfunction before treatment, 68% maintained potency. Age, initial PSA, T stage, Gleason score, prostate volume, and percent positive cores did not correlate with BPFS. Stratifying by favorable vs. unfavorable IR groups did not affect BPFS. HDR brachytherapy monotherapy represents a safe and highly effective treatment for IR prostate cancer patients with long-term follow-up. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  12. Predictors of toxicity after image-guided high-dose-rate interstitial brachytherapy for gynecologic cancer.

    Science.gov (United States)

    Lee, Larissa J; Viswanathan, Akila N

    2012-12-01

    To identify predictors of grade 3-4 complications and grade 2-4 rectal toxicity after three-dimensional image-guided high-dose-rate (HDR) interstitial brachytherapy for gynecologic cancer. Records were reviewed for 51 women (22 with primary disease and 29 with recurrence) treated with HDR interstitial brachytherapy. A single interstitial insertion was performed with image guidance by computed tomography (n = 43) or magnetic resonance imaging (n = 8). The median delivered dose in equivalent 2-Gy fractions was 72.0 Gy (45 Gy for external-beam radiation therapy and 24 Gy for brachytherapy). Toxicity was reported according to the Common Toxicity Criteria for Adverse Events. Actuarial toxicity estimates were calculated by the Kaplan-Meier method. At diagnosis, the median patient age was 62 years and the median tumor size was 3.8 cm. The median D90 and V100 were 71.4 Gy and 89.5%; the median D2cc for the bladder, rectum, and sigmoid were 64.6 Gy, 61.0 Gy, and 52.7 Gy, respectively. The actuarial rates of all grade 3-4 complications at 2 years were 20% gastrointestinal, 9% vaginal, 6% skin, 3% musculoskeletal, and 2% lymphatic. There were no grade 3-4 genitourinary complications and no grade 5 toxicities. Grade 2-4 rectal toxicity was observed in 10 patients, and grade 3-4 complications in 4; all cases were proctitis with the exception of 1 rectal fistula. D2cc for rectum was higher for patients with grade 2-4 (68 Gy vs 57 Gy for grade 0-1, P=.03) and grade 3-4 (73 Gy vs 58 Gy for grade 0-2, P=.02) rectal toxicity. The estimated dose that resulted in a 10% risk of grade 2-4 rectal toxicity was 61.8 Gy (95% confidence interval, 51.5-72.2 Gy). Image-guided HDR interstitial brachytherapy results in acceptable toxicity for women with primary or recurrent gynecologic cancer. D2cc for the rectum is a reliable predictor of late rectal complications. Three-dimensional-based treatment planning should be performed to ensure adequate tumor coverage while minimizing the D2cc to the

  13. High-Dose-Rate Monotherapy for Localized Prostate Cancer: 10-Year Results

    Energy Technology Data Exchange (ETDEWEB)

    Hauswald, Henrik; Kamrava, Mitchell R.; Fallon, Julia M.; Wang, Pin-Chieh; Park, Sang-June; Van, Thanh; Borja, Lalaine; Steinberg, Michael L.; Demanes, D. Jeffrey, E-mail: JDemanes@mednet.ucla.edu

    2016-03-15

    Purpose: High-dose-rate (HDR) brachytherapy was originally used with external beam radiation therapy (EBRT) to increase the dose to the prostate without injuring the bladder or rectum. Numerous studies have reported HDR brachytherapy is safe and effective. We adapted it for use without EBRT for cases not requiring lymph node treatment. Patients and Methods: We entered the patient demographics, disease characteristics, and treatment parameters into a prospective registry and serially added follow-up data for 448 men with low-risk (n=288) and intermediate-risk (n=160) prostate cancer treated from 1996 to 2009. Their median age was 64 years (range 42-90). The median prostate-specific antigen (PSA) level was 6.0 ng/mL (range 0.2-18.2). The Gleason score was ≤6 in 76% and 7 in 24%. The median dose was 43.5 Gy in 6 fractions. The clinical and biochemical disease control and survival rates were calculated. Adverse events were graded according to the Common Toxicity Criteria of Adverse Events. Results: The median follow-up period was 6.5 years (range 0.3-15.3). The actuarial 6- and 10-year PSA progression-free survival was 98.6% (95% confidence interval [CI] 96.9%-99.4%) and 97.8% (95% CI 95.5%-98.9%). Overall survival at 10 years was 76.7% (95% CI 69.9%-82.2%). The local control, distant metastasis-free survival, and cause-specific survival were 99.7% (95% CI 97.9%-99.9%), 98.9% (95% CI 96.3%-99.7%), and 99.1% (95% CI 95.8%-99.8%). T stage, initial PSA level, Gleason score, National Comprehensive Cancer Network risk group, patient age, and androgen deprivation therapy did not significantly correlate with disease control or survival. No late grade 3 to 4 rectal toxicities developed. Late grade 3 to 4 genitourinary toxicity occurred in 4.9% (grade 3 in 4.7%). Conclusions: HDR monotherapy is a safe and highly effective treatment of low- and intermediate-risk prostate cancer.

  14. Direction-Modulated Brachytherapy for High-Dose-Rate Treatment of Cervical Cancer. I: Theoretical Design

    Energy Technology Data Exchange (ETDEWEB)

    Han, Dae Yup [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States); Department of Electrical and Computer Engineering, University of California San Diego, La Jolla, California (United States); Webster, Matthew J. [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States); Department of Physics, University of California San Diego, La Jolla, California (United States); Scanderbeg, Daniel J.; Yashar, Catheryn; Choi, Dongju; Song, Bongyong [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States); Devic, Slobodan [Medical Physics Unit, McGill University, Montréal, Québec (Canada); Department of Radiation Oncology, Jewish General Hospital, Montréal, Québec (Canada); Ravi, Ananth [Department of Medical Physics, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); Song, William Y., E-mail: wyjsong@gmail.com [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States); Department of Medical Physics, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada)

    2014-07-01

    Purpose: To demonstrate that utilization of the direction-modulated brachytherapy (DMBT) concept can significantly improve treatment plan quality in the setting of high-dose-rate (HDR) brachytherapy for cervical cancer. Methods and Materials: The new, MRI-compatible, tandem design has 6 peripheral holes of 1.3-mm diameter, grooved along a nonmagnetic tungsten-alloy rod (ρ = 18.0 g/cm{sup 3}), enclosed in Delrin tubing (polyoxymethylene, ρ = 1.41 g/cm{sup 3}), with a total thickness of 6.4 mm. The Monte Carlo N-Particle code was used to calculate the anisotropic {sup 192}Ir dose distributions. An in-house-developed inverse planning platform, geared with simulated annealing and constrained-gradient optimization algorithms, was used to replan 15 patient cases (total 75 plans) treated with a conventional tandem and ovoids (T and O) applicator. Prescription dose was 6 Gy. For replanning, we replaced the conventional tandem with that of the new DMBT tandem for optimization but left the ovoids in place and kept the dwell positions as originally planned. All DMBT plans were normalized to match the high-risk clinical target volume V100 coverage of the T and O plans. Results: In general there were marked improvements in plan quality for the DMBT plans. On average, D2cc for the bladder, rectum, and sigmoid were reduced by 0.59 ± 0.87 Gy (8.5% ± 28.7%), 0.48 ± 0.55 Gy (21.1% ± 27.2%), and 0.10 ± 0.38 Gy (40.6% ± 214.9%) among the 75 plans, with best single-plan reductions of 3.20 Gy (40.8%), 2.38 Gy (40.07%), and 1.26 Gy (27.5%), respectively. The high-risk clinical target volume D90 was similar, with 6.55 ± 0.96 Gy and 6.59 ± 1.06 Gy for T and O and DMBT, respectively. Conclusions: Application of the DMBT concept to cervical cancer allowed for improved organ at risk sparing while achieving similar target coverage on a sizeable patient population, as intended, by maximally utilizing the anatomic information contained in 3-dimensional

  15. Learning curve of MRI-based planning for high-dose-rate brachytherapy for prostate cancer.

    Science.gov (United States)

    Buus, Simon; Rylander, Susanne; Hokland, Steffen; Søndergaard, Christian Skou; Pedersen, Erik Morre; Tanderup, Kari; Bentzen, Lise

    2016-01-01

    To evaluate introduction of MRI-based high-dose-rate brachytherapy (HDRBT), including procedure times, dose-volume parameters, and perioperative morbidity. Study included 42 high-risk prostate cancer patients enrolled in a clinical protocol, offering external beam radiotherapy + two HDRBT 8.5 Gy boosts. Time was recorded for initiation of anesthesia (A), fixation of needle implant (B), end of MR imaging (C), plan approval (D), and end of HDRBT delivery (E). We defined time A-E as total procedure time, A-B as operating room time, B-C as MRI procedure time, C-D as treatment planning time, and D to E as treatment delivery time. Dose-volume parameters were retrieved from the dose planning system. Results from the first 21 patients were compared with the last 21 patients. Total procedure time, operating room time, MRI procedure time, and treatment planning time decreased significantly from average 7.6 to 5.3 hours (p < 0.01), 3.6 to 2.4 hours (p < 0.01), 1.6 to 0.8 hours (p < 0.01), and 2.0 to 1.3 hours (p < 0.01), respectively. HDRBT delivery time remained unchanged at 0.5 hours. Clinical target volume prostate+3mmD90 fulfilled planning aim in 92% of procedures and increased significantly from average 8.3 to 9.0 Gy (p < 0.01). Urethral D0.1 cm(3) and rectal D2 cm(3) fulfilled planning aim in 78% and 95% of procedures, respectively, and did not change significantly. Hematuria occurred in (95%), hematoma (80%), moderate to strong pain (35%), and urinary retention (5%) of procedures. After introduction of MRI-based HDRBT, procedure times were significantly reduced. D90 Clinical target volumeprostate+3mm fulfilled constraints in most patients and improved over time, but not at expense of an increased urethral or rectal dose. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  16. Monte Carlo study of radiation dose enhancement by gadolinium in megavoltage and high dose rate radiotherapy.

    Directory of Open Access Journals (Sweden)

    Daniel G Zhang

    Full Text Available MRI is often used in tumor localization for radiotherapy treatment planning, with gadolinium (Gd-containing materials often introduced as a contrast agent. Motexafin gadolinium is a novel radiosensitizer currently being studied in clinical trials. The nanoparticle technologies can target tumors with high concentration of high-Z materials. This Monte Carlo study is the first detailed quantitative investigation of high-Z material Gd-induced dose enhancement in megavoltage external beam photon therapy. BEAMnrc, a radiotherapy Monte Carlo simulation package, was used to calculate dose enhancement as a function of Gd concentration. Published phase space files for the TrueBeam flattening filter free (FFF and conventional flattened 6MV photon beams were used. High dose rate (HDR brachytherapy with Ir-192 source was also investigated as a reference. The energy spectra difference caused a dose enhancement difference between the two beams. Since the Ir-192 photons have lower energy yet, the photoelectric effect in the presence of Gd leads to even higher dose enhancement in HDR. At depth of 1.8 cm, the percent mean dose enhancement for the FFF beam was 0.38±0.12, 1.39±0.21, 2.51±0.34, 3.59±0.26, and 4.59±0.34 for Gd concentrations of 1, 5, 10, 15, and 20 mg/mL, respectively. The corresponding values for the flattened beam were 0.09±0.14, 0.50±0.28, 1.19±0.29, 1.68±0.39, and 2.34±0.24. For Ir-192 with direct contact, the enhanced were 0.50±0.14, 2.79±0.17, 5.49±0.12, 8.19±0.14, and 10.80±0.13. Gd-containing materials used in MRI as contrast agents can also potentially serve as radiosensitizers in radiotherapy. This study demonstrates that Gd can be used to enhance radiation dose in target volumes not only in HDR brachytherapy, but also in 6 MV FFF external beam radiotherapy, but higher than the currently used clinical concentration (>5 mg/mL would be needed.

  17. Monte Carlo study of radiation dose enhancement by gadolinium in megavoltage and high dose rate radiotherapy.

    Science.gov (United States)

    Zhang, Daniel G; Feygelman, Vladimir; Moros, Eduardo G; Latifi, Kujtim; Zhang, Geoffrey G

    2014-01-01

    MRI is often used in tumor localization for radiotherapy treatment planning, with gadolinium (Gd)-containing materials often introduced as a contrast agent. Motexafin gadolinium is a novel radiosensitizer currently being studied in clinical trials. The nanoparticle technologies can target tumors with high concentration of high-Z materials. This Monte Carlo study is the first detailed quantitative investigation of high-Z material Gd-induced dose enhancement in megavoltage external beam photon therapy. BEAMnrc, a radiotherapy Monte Carlo simulation package, was used to calculate dose enhancement as a function of Gd concentration. Published phase space files for the TrueBeam flattening filter free (FFF) and conventional flattened 6MV photon beams were used. High dose rate (HDR) brachytherapy with Ir-192 source was also investigated as a reference. The energy spectra difference caused a dose enhancement difference between the two beams. Since the Ir-192 photons have lower energy yet, the photoelectric effect in the presence of Gd leads to even higher dose enhancement in HDR. At depth of 1.8 cm, the percent mean dose enhancement for the FFF beam was 0.38±0.12, 1.39±0.21, 2.51±0.34, 3.59±0.26, and 4.59±0.34 for Gd concentrations of 1, 5, 10, 15, and 20 mg/mL, respectively. The corresponding values for the flattened beam were 0.09±0.14, 0.50±0.28, 1.19±0.29, 1.68±0.39, and 2.34±0.24. For Ir-192 with direct contact, the enhanced were 0.50±0.14, 2.79±0.17, 5.49±0.12, 8.19±0.14, and 10.80±0.13. Gd-containing materials used in MRI as contrast agents can also potentially serve as radiosensitizers in radiotherapy. This study demonstrates that Gd can be used to enhance radiation dose in target volumes not only in HDR brachytherapy, but also in 6 MV FFF external beam radiotherapy, but higher than the currently used clinical concentration (>5 mg/mL) would be needed.

  18. Performance assessment of the BEBIG MultiSource® high dose rate brachytherapy treatment unit

    Science.gov (United States)

    Palmer, Antony; Mzenda, Bongile

    2009-12-01

    A comprehensive system characterisation was performed of the Eckert & Ziegler BEBIG GmbH MultiSource® High Dose Rate (HDR) brachytherapy treatment unit with an 192Ir source. The unit is relatively new to the UK market, with the first installation in the country having been made in the summer of 2009. A detailed commissioning programme was devised and is reported including checks of the fundamental parameters of source positioning, dwell timing, transit doses and absolute dosimetry of the source. Well chamber measurements, autoradiography and video camera analysis techniques were all employed. The absolute dosimetry was verified by the National Physical Laboratory, UK, and compared to a measurement based on a calibration from PTB, Germany, and the supplied source certificate, as well as an independent assessment by a visiting UK centre. The use of the 'Krieger' dosimetry phantom has also been evaluated. Users of the BEBIG HDR system should take care to avoid any significant bend in the transfer tube, as this will lead to positioning errors of the source, of up to 1.0 mm for slight bends, 2.0 mm for moderate bends and 5.0 mm for extreme curvature (depending on applicators and transfer tube used) for the situations reported in this study. The reason for these errors and the potential clinical impact are discussed. Users should also note the methodology employed by the system for correction of transit doses, and that no correction is made for the initial and final transit doses. The results of this investigation found that the uncorrected transit doses lead to small errors in the delivered dose at the first dwell position, of up to 2.5 cGy at 2 cm (5.6 cGy at 1 cm) from a 10 Ci source, but the transit dose correction for other dwells was accurate within 0.2 cGy. The unit has been mechanically reliable, and source positioning accuracy and dwell timing have been reproducible, with overall performance similar to other existing HDR equipment. The unit is capable of high

  19. Patient-specific dose calculation methods for high-dose-rate iridium-192 brachytherapy

    Science.gov (United States)

    Poon, Emily S.

    In high-dose-rate 192Ir brachytherapy, the radiation dose received by the patient is calculated according to the AAPM Task Group 43 (TG-43) formalism. This table-based dose superposition method uses dosimetry parameters derived with the radioactive 192Ir source centered in a water phantom. It neglects the dose perturbations caused by inhomogeneities, such as the patient anatomy, applicators, shielding, and radiographic contrast solution. In this work, we evaluated the dosimetric characteristics of a shielded rectal applicator with an endocavitary balloon injected with contrast solution. The dose distributions around this applicator were calculated by the GEANT4 Monte Carlo (MC) code and measured by ionization chamber and GAFCHROMIC EBT film. A patient-specific dose calculation study was then carried out for 40 rectal treatment plans. The PTRAN_CT MC code was used to calculate the dose based on computed tomography (CT) images. This study involved the development of BrachyGUI, an integrated treatment planning tool that can process DICOM-RT data and create PTRAN_CT input initialization files. BrachyGUI also comes with dose calculation and evaluation capabilities. We proposed a novel scatter correction method to account for the reduction in backscatter radiation near tissue-air interfaces. The first step requires calculating the doses contributed by primary and scattered photons separately, assuming a full scatter environment. The scatter dose in the patient is subsequently adjusted using a factor derived by MC calculations, which depends on the distances between the point of interest, the 192Ir source, and the body contour. The method was validated for multicatheter breast brachytherapy, in which the target and skin doses for 18 patient plans agreed with PTRAN_CT calculations better than 1%. Finally, we developed a CT-based analytical dose calculation method. It corrects for the photon attenuation and scatter based upon the radiological paths determined by ray tracing

  20. In vivo dose verification method in catheter based high dose rate brachytherapy.

    Science.gov (United States)

    Jaselskė, Evelina; Adlienė, Diana; Rudžianskas, Viktoras; Urbonavičius, Benas Gabrielis; Inčiūra, Arturas

    2017-12-01

    In vivo dosimetry is a powerful tool for dose verification in radiotherapy. Its application in high dose rate (HDR) brachytherapy is usually limited to the estimation of gross errors, due to inability of the dosimetry system/ method to record non-uniform dose distribution in steep dose gradient fields close to the radioactive source. In vivo dose verification in interstitial catheter based HDR brachytherapy is crucial since the treatment is performed inserting radioactive source at the certain positions within the catheters that are pre-implanted into the tumour. We propose in vivo dose verification method for this type of brachytherapy treatment which is based on the comparison between experimentally measured and theoretical dose values calculated at well-defined locations corresponding dosemeter positions in the catheter. Dose measurements were performed using TLD 100-H rods (6 mm long, 1 mm diameter) inserted in a certain sequences into additionally pre-implanted dosimetry catheter. The adjustment of dosemeter positioning in the catheter was performed using reconstructed CT scans of patient with pre-implanted catheters. Doses to three Head&Neck and one Breast cancer patient have been measured during several randomly selected treatment fractions. It was found that the average experimental dose error varied from 4.02% to 12.93% during independent in vivo dosimetry control measurements for selected Head&Neck cancer patients and from 7.17% to 8.63% - for Breast cancer patient. Average experimental dose error was below the AAPM recommended margin of 20% and did not exceed the measurement uncertainty of 17.87% estimated for this type of dosemeters. Tendency of slightly increasing average dose error was observed in every following treatment fraction of the same patient. It was linked to the changes of theoretically estimated dosemeter positions due to the possible patient's organ movement between different treatment fractions, since catheter reconstruction was

  1. Radioablation of liver malignancies with interstitial high-dose-rate brachytherapy. Complications and risk factors

    Energy Technology Data Exchange (ETDEWEB)

    Mohnike, Konrad; Wolf, Steffen; Damm, Robert; Seidensticker, Max; Seidensticker, Ricarda; Fischbach, Frank; Pech, Maciej; Ricke, Jens [Otto-von-Guericke-Universitaet, Klinik fuer Radiologie und Nuklearmedizin, Universitaetsklinikum Magdeburg A.oe.R., Magdeburg (Germany); Peters, Nils; Hass, Peter; Gademann, Guenther [Otto-von-Guericke-Universitaet, Klinik fuer Strahlentherapie, Universitaetsklinikum Magdeburg A.oe.R., Magdeburg (Germany)

    2016-05-15

    To evaluate complications and identify risk factors for adverse events in patients undergoing high-dose-rate interstitial brachytherapy (iBT). Data from 192 patients treated in 343 CT- or MRI-guided interventions from 2006-2009 at our institution were analyzed. In 41 %, the largest tumor treated was ≥ 5 cm, 6 % of the patients had tumors ≥ 10 cm. Prior to iBT, 60 % of the patients had chemotherapy, 22 % liver resection, 19 % thermoablation or transarterial chemoembolization (TACE). Safety was the primary endpoint; survival data were obtained as the secondary endpoints. During follow-up, MRI or CT imaging was performed and clinical and laboratory parameters were obtained. The rate of major complications was below 5 %. Five major bleedings (1.5 %) occurred. The frequency of severe bleeding was significantly higher in patients with advanced liver cirrhosis. One patient developed signs of a nonclassic radiation-induced liver disease. In 3 patients, symptomatic gastrointestinal (GI) ulcers were detected. A dose exposure to the GI wall above 14 Gy/ml was a reliable threshold to predict ulcer formation. A combination of C-reactive protein ≥ 165 mg/l and/or leukocyte count ≥ 12.7 Gpt/l on the second day after the intervention predicted infection (sensitivity 90.0 %; specificity 92.8 %.) Two patients (0.6 %) died within 30 days. Median overall survival after the first liver treatment was 20.1 months for all patients and the local recurrence-free surviving proportion was 89 % after 12 months. Image-guided iBT yields a low rate of major complications and is effective. (orig.) [German] Evaluierung der Komplikationsrate und Identifizierung von Risikofaktoren fuer Komplikationen und Nebenwirkungen bei Patienten mit Lebermalignomen, die mit der hochdosierten interstitiellen Brachytherapie (iBT) behandelt wurden. Von 2006 bis 2009 wurden 192 Patienten in 343 CT- oder MRT-gefuehrten Interventionen behandelt und deren Daten ausgewertet. Der groesste behandelte Tumor war in

  2. CT-guided high-dose-rate brachytherapy of unresectable hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Collettini, Federico; Schreiber, Nadja; Schnapauff, Dirk; Denecke, Timm; Hamm, Bernd; Gebauer, Bernhard [ChariteUniversitaetsmedizin Berlin, Department of Diagnostic and Interventional Radiology, Berlin (Germany); Wust, Peter [ChariteUniversitaetsmedizin Berlin, Department of Radiation Oncology, Berlin (Germany); Schott, Eckart [Universitaetsmedizin Berlin, Department of Gastroenterology, Berlin (Germany)

    2015-05-01

    The purpose of the present study was to evaluate the clinical outcome of CT-guided high-dose-rate brachytherapy (CT-HDRBT) in patients with unresectable hepatocellular carcinoma (HCC). Over a 6-year period, 98 patients with 212 unresectable HCC underwent CT-HDRBT applying a {sup 192}Ir source at our institution. Magnetic resonance imaging (MRI) follow-up was performed 6 weeks after the intervention and then every 3 months. The primary endpoint was local tumor control (LTC); secondary endpoints included progression-free survival (PFS) and overall survival (OS). Patients were available for MRI evaluation for a mean follow-up of 23.1 months (range 4-64 months; median 20 months). Mean tumor diameter was 5 cm (range 1.8-12 cm). Eighteen of 212 (8.5 %) tumors showed local progression after a mean LTC of 21.1 months. In all, 67 patients (68.4 %) experienced distant tumor progression. The mean PFS was 15.2 months. Forty-six patients died during the follow-up period. Median OS was 29.2 months. Actuarial 1-, 2-, and 3-year OS rates were 80, 62, and 46 %, respectively. CT-HDRBT is an effective therapy to attain local tumor control in patients with unresectable HCC. Prospective randomized studies comparing CT-HDRBT with the standard treatments like Radiofrequency ablation (RFA) and chemoembolization (TACE) are mandatory. (orig.) [German] Zweck der vorliegenden Arbeit war die Analyse der klinischen Effektivitaet der CT-gesteuerten Hochdosis-Brachytherapie (CT-HDRBT) bei Patienten mit inoperablem hepatozellulaeren Karzinom (HCC). Ueber einen Zeitraum von 6 Jahren, wurden an unserer Klinik 98 Patienten mit 212 inoperablen HCC mittels CT-HDRBT mit {sup 192}Ir behandelt. MRT-Verlaufskontrollen erfolgten 6 Wochen nach der Intervention und dann alle 3 Monate. Primaerer Endpunkt der Studie war die lokale Tumorkontrolle (LTC); sekundaere Endpunkte waren das progressionsfreie Ueberleben (PFS) und Gesamtueberleben (OS). Die mittlere Nachbeobachtungszeit betrug 23,1 Monate (Spanne 4

  3. Adaptation of the CVT algorithm for catheter optimization in high dose rate brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Poulin, Eric; Fekete, Charles-Antoine Collins; Beaulieu, Luc [Département de Physique, de Génie Physique et d’Optique et Centre de recherche sur le cancer de l’Université Laval, Université Laval, Québec, Québec G1V 0A6, Canada and Département de Radio-Oncologie et Axe oncologie du Centre de Recherche du CHU de Québec, CHU de Québec, 11 Côte du Palais, Québec, Québec G1R 2J6 (Canada); Létourneau, Mélanie [Département de Radio-Oncologie, CHU de Québec, 11 Côte du Palais, Québec, Québec G1R 2J6 (Canada); Fenster, Aaron [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Ontario N6A 5K8 (United Kingdom); Pouliot, Jean [Department of Radiation Oncology, University of California San Francisco, Helen Diller Family Comprehensive Cancer Center, 1600 Divisadero Street, San Francisco, California 94143-1708 (United States)

    2013-11-15

    Purpose: An innovative, simple, and fast method to optimize the number and position of catheters is presented for prostate and breast high dose rate (HDR) brachytherapy, both for arbitrary templates or template-free implants (such as robotic templates).Methods: Eight clinical cases were chosen randomly from a bank of patients, previously treated in our clinic to test our method. The 2D Centroidal Voronoi Tessellations (CVT) algorithm was adapted to distribute catheters uniformly in space, within the maximum external contour of the planning target volume. The catheters optimization procedure includes the inverse planning simulated annealing algorithm (IPSA). Complete treatment plans can then be generated from the algorithm for different number of catheters. The best plan is chosen from different dosimetry criteria and will automatically provide the number of catheters and their positions. After the CVT algorithm parameters were optimized for speed and dosimetric results, it was validated against prostate clinical cases, using clinically relevant dose parameters. The robustness to implantation error was also evaluated. Finally, the efficiency of the method was tested in breast interstitial HDR brachytherapy cases.Results: The effect of the number and locations of the catheters on prostate cancer patients was studied. Treatment plans with a better or equivalent dose distributions could be obtained with fewer catheters. A better or equal prostate V100 was obtained down to 12 catheters. Plans with nine or less catheters would not be clinically acceptable in terms of prostate V100 and D90. Implantation errors up to 3 mm were acceptable since no statistical difference was found when compared to 0 mm error (p > 0.05). No significant difference in dosimetric indices was observed for the different combination of parameters within the CVT algorithm. A linear relation was found between the number of random points and the optimization time of the CVT algorithm. Because the

  4. Optimal bladder filling during high-dose-rate intracavitary brachytherapy for cervical cancer: a dosimetric study

    Directory of Open Access Journals (Sweden)

    Umesh Mahantshetty

    2017-04-01

    Full Text Available Purpose: The aim of this study is to compare 3D dose volume histogram (DVH parameters of bladder and other organs at risk with different bladder filling protocol during high-dose-rate intracavitary brachytherapy (HDR-ICBT in cervical cancer, and to find optimized bladder volume. Material and methods : This dosimetric study was completed with 21 patients who underwent HDR-ICBT with computed tomography/magnetic resonance compatible applicator as a routine treatment. Computed tomography planning was done for each patient with bladder emptied (series 1, after 50 ml (series 2, and 100 ml (series 3 bladder filling with a saline infusion through the bladder catheter. Contouring was done on the Eclipse Planning System. 7 Gy to point A was prescribed with the standard loading patterns. Various 3D DVH parameters including 0.1 cc, 1 cc, 2 cc doses and mean doses to the OAR’s were noted. Paired t-test was performed. Results : The mean (± SD bladder volume was 64.5 (± 25 cc, 116.2 (± 28 cc, and 172.9 (± 29 cc, for series 1, 2, and 3, respectively. The 0.1 cm 3 ,1 cm 3 , 2 cm 3 mean bladder doses for series 1, series 2, and series 3 were 9.28 ± 2.27 Gy, 7.38 ± 1.72 Gy, 6.58 ± 1.58 Gy; 9.39 ± 2.28 Gy, 7.85 ± 1.85 Gy, 7.05 ± 1.59 Gy, and 10.09 ± 2.46 Gy, 8.33 ± 1.75 Gy, 7.6 ± 1.55 Gy, respectively. However, there was a trend towards higher bladder doses in series 3. Similarly, for small bowel dose 0.1 cm 3 , 1 cm 3 , and 2 cm 3 in series 1, 2, and 3 were 5.44 ± 2.2 Gy, 4.41 ± 1.84 Gy, 4 ± 1.69 Gy; 4.57 ± 2.89 Gy, 3.78 ± 2.21 Gy, 3.35 ± 2.02 Gy, and 4.09 ± 2.38 Gy, 3.26 ± 1.8 Gy, 3.05 ± 1.58 Gy. Significant increase in small bowel dose in empty bladder (series 1 compared to full bladder (series 3 (p = 0.03 was noted. However, the rectal and sigmoid doses were not significantly affected with either series. Conclusions : Bladder filling protocol with 50 ml and 100 ml was well tolerated and achieved a reasonably reproducible bladder volume

  5. Advantages of high-dose rate (HDR) brachytherapy in treatment of prostate cancer

    Science.gov (United States)

    Molokov, A. A.; Vanina, E. A.; Tseluyko, S. S.

    2017-09-01

    One of the modern methods of preserving organs radiation treatment is brachytherapy. This article analyzes the results of prostate brachytherapy. These studies of the advantages of high dose brachytherapy lead to the conclusion that this method of radiation treatment for prostate cancer has a favorable advantage in comparison with remote sensing methods, and is competitive, preserving organs in comparison to surgical methods of treatment. The use of the method of polyfocal transperineal biopsy during the brachytherapy session provides information on the volumetric spread of prostate cancer and adjust the dosimetry plan taking into account the obtained data.

  6. Numerical reconstruction of high dose rate zones due to the Fukushima Dai-ichi Nuclear Power Plant accident.

    Science.gov (United States)

    Katata, Genki; Terada, Hiroaki; Nagai, Haruyasu; Chino, Masamichi

    2012-09-01

    To understand how the high dose rate zones were created during the Fukushima Dai-ichi Nuclear Power Plant (FNPP1) accident on March 2011, the atmospheric dispersion of radionuclides during the period from 15 to 17 March was reproduced by using a computer-based nuclear emergency response system, WSPEEDI-II. With use of limited environmental monitoring data, prediction accuracy of meteorological and radiological fields by the system was improved to obtain best estimates of release rates, radiation dose maps, and plume movements. A large part of current high dose rate zones in Fukushima was explained by simulated surface deposition of radionuclides due to major releases of radionuclides on 15 March. In the simulation, the highest dose rate zones to the northwest of FNPP1 were created by a significant deposition of radionuclides discharged from FNPP1 during the afternoon. The results indicate that two environmental factors, i.e., rainfall and topography, strongly affected the spatial patterns of surface deposition of radionuclides. The wet deposition due to rainfall particularly played an important role in the formation of wide and heterogeneous distributions of high dose rate zones. The simulation also demonstrated that the radioactive plume flowed along the valleys to its leeward, which can expand the areas of a large amount of surface deposition in complex topography. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. SU-E-T-165: Characterization of Dose Distributions in High-Dose-Rate Surface Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Buzurovic, I; Hansen, J; Bhagwat, M; O’Farrell, D; Damato, A; Friesen, S; Devlin, P; Cormack, R [Dana-Farber/Brigham and Women’s Cancer Center, Harvard Medical School, Boston, MA (United States)

    2015-06-15

    Purpose: To characterize dose distributions in high-dose-rate(HDR) surface brachytherapy using an Ir-125 source for different geometries, field sizes and topology of the clinical targets(CT). To investigate the depth doses at the central axis(CAX), edges of the treatment fields(E), and lateral dose distributions(L) present when using flap applicators in skin cancer treatments. Methods: When malignancies diagnosed on the skin are treated, various geometries of the CT require proper adaptation of the flap or custom-made applicators to the treatment site. Consequently, the dose at the depth on CAX and field edges changes with variation of the curvatures and size of the applicators. To assess the dose distributions, we created a total of 10 treatment plans(TP) for 10×10 and 20×20 field sizes(FS) with a step size of 1cm. The geometry of the applicators was: planar(PA), curved to 30(CA30) and 60(CA60) degrees with respect to the CAX, half-cylinder(HC), and cylindrical shape(CS). One additional TP was created in which the applicators were positioned to form a dome shape(DS) with a diameter of 16cm. This TP was used to emulate treatment of the average sized scalp. All TPs were optimized to deliver a prescription dose at 8mm equidistantly from the planes containing the dwell positions. This optimization is equivalent to the clinical arrangement since the SSD for the flap applicators is 5mm and the prescription depth is 3mm in the majority of clinical cases. Results: The depths (in mm) of the isodose lines were: FS(10×10):PA[90%(9.1CAX,8.0E,7.6L),50%(28.3CAX,20E,17.3L), 25%(51.1CAX,40E,27L)],CA30[90%(10.3CAX,8.2E,7.9L),50%(32.1CAX, 16.2E,15.8L),25%(61.3CAX,36.7E,31.8L)],CA60[90%(12.2CAX,6.1E,6.3L ),50%(47CAX,14E,16.6L),25%(70.8CAX,31.9E,35.4L)],HC[90%(11.1CA X,6.3E,7.3L),50%(38.3CAX,14.6E,16.1L),25%(66.2CAX,33.8E,34.2L)];FS (20×20):PA[90%(11.1CAX,9.0E,7.0L),50%(34.4CAX,21.9E,15.3L),25%(7 0.4CAX,50.9E,34.8L)],CA30[90%(10.9CAX,7.5E,7.1L),50%(38.8CAX,16. 7E,15.4L),25

  8. Image-Guided High-Dose-Rate (HDR) Boost Localization Using MRI/MR Spectroscopy: A Correlation Study with Biopsy

    OpenAIRE

    Vigneault, Eric; Mbodji, Khaly; Racine, Louis G; Chevrette, Eric; Lavallee, Marie C; Martin, Andr?-Guy; Despres, Philippe; Beaulieu, Luc

    2016-01-01

    Purpose: The purpose of this study is to compare the blind interpretations of magnetic resonance imaging (MRI) sequences, diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC), mapping, and magnetic resonance spectroscopy (MRS) of the prostate, in comparison to prostate biopsy to identify a valid dominant intraprostatic lesion (DIL) for dose escalation using high-dose rate brachytherapy. Methods: MRI/MRS were performed on 20 patients with intermediate risk adenocarcinoma of t...

  9. Intraoperative High Dose Rate 32P Brachytherapy for Diffuse Recalcitrant Conjunctival Neoplasms: A Retrospective Case Series and Report of Toxicity

    Science.gov (United States)

    Marr, Brian P.; Abramson, David H.; Cohen, Gil’ad N.; Williamson, Matthew J.; McCormick, Beryl; Barker, Christopher A.

    2017-01-01

    improved in five of the seven eyes. Conclusions and Relevance Our results show the use of Intraoperative High Dose Rate 32P Brachytherapy in selected cases of recalcitrant diffuse conjunctival neoplasms. This technique offers a novel adjunct in the treatment of these cancers. Further follow-up and study is warranted. Trial Registration N/A PMID:25502420

  10. Use of ultrasound in image-guided high-dose-rate brachytherapy: enumerations and arguments

    OpenAIRE

    Susovan Banerjee; Tejinder Kataria; Deepak Gupta; Shikha Goyal; Shyam Singh Bisht; Trinanjan Basu; Ashu Abhishek

    2017-01-01

    Inherently, brachytherapy is the most conformal radiotherapeutic technique. As an aid to brachytherapy, ultrasonography (USG) serves as a portable, inexpensive, and simple to use method allowing for accurate, reproducible, and adaptive treatments. Some newer brachytherapy planning systems have incorporated USG as the sole imaging modality. Ultrasonography has been successfully used to place applicator and dose planning for prostate, cervix, and anal canal cancers. It can guide placement of br...

  11. Radiochromic film-based quality assurance for CT-based high-dose-rate brachytherapy.

    Science.gov (United States)

    Asgharizadeh, Saeid; Bekerat, Hamed; Syme, Alasdair; Aldelaijan, Saad; DeBlois, François; Vuong, Té; Evans, Michael; Seuntjens, Jan; Devic, Slobodan

    2015-01-01

    In the past, film dosimetry was developed into a powerful tool for external beam radiotherapy treatment verification and quality assurance. The objective of this work was the development and clinical testing of the EBT3 model GafChromic film based brachytherapy quality assurance (QA) system. Retrospective dosimetry study was performed to test a patient-specific QA system for preoperative endorectal brachytherapy that uses a radiochromic film dosimetry system. A dedicated phantom for brachytherapy applicator used for rectal cancer treatment was fabricated enabling us to compare calculated-to-measured dose distributions. Starting from the same criteria used for external beam intensity-modulated radiation therapy QA (3%, 3 mm), passing criteria for high- and low-dose gradient regions were subsequently determined. Finally, we investigated the QA system's sensitivity to controlled source positional errors on selected patient plans. In low-dose gradient regions, measured dose distributions with criteria of 3%, 3 mm barely passed the test, as they showed 95% passing pixels. However, in the high-dose gradient region, a more stringent condition could be established. Both criteria of 2%, 3 mm and 3%, 2 mm with gamma function calculated using normalization to the same absolute dose value in both measured and calculated dose distributions, and matrix sizes rescaled to match each other showed more than 95% of pixels passing, on average, for 15 patient plans analyzed. Although the necessity of the patient-specific brachytherapy QA needs yet to be justified, we described a radiochromic film dosimetry-based QA system that can be a part of the brachytherapy commissioning process, as well as yearly QA program. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  12. Dose optimization of intra-operative high dose rate interstitial brachytherapy implants for soft tissue sarcoma

    Directory of Open Access Journals (Sweden)

    Jamema Swamidas

    2009-01-01

    Full Text Available Objective : A three dimensional (3D image-based dosimetric study to quantitatively compare geometric vs. dose-point optimization in combination with graphical optimization for interstitial brachytherapy of soft tissue sarcoma (STS. Materials and Methods : Fifteen consecutive STS patients, treated with intra-operative, interstitial Brachytherapy, were enrolled in this dosimetric study. Treatment plans were generated using dose points situated at the "central plane between the catheters", "between the catheters throughout the implanted volume", at "distances perpendicular to the implant axis" and "on the surface of the target volume" Geometrically optimized plans had dose points defined between the catheters, while dose-point optimized plans had dose points defined at a plane perpendicular to the implant axis and on the target surface. Each plan was graphically optimized and compared using dose volume indices. Results : Target coverage was suboptimal with coverage index (CI = 0.67 when dose points were defined at the central plane while it was superior when the dose points were defined at the target surface (CI=0.93. The coverage of graphically optimized plans (GrO was similar to non-GrO with dose points defined on surface or perpendicular to the implant axis. A similar pattern was noticed with conformity index (0.61 vs. 0.82. GrO were more conformal and less homogeneous compared to non-GrO. Sum index was superior for dose points defined on the surface of the target and relatively inferior for plans with dose points at other locations (1.35 vs. 1.27. Conclusions : Optimization with dose points defined away from the implant plane and on target results in superior target coverage with optimal values of other indices. GrO offer better target coverage for implants with non-uniform geometry and target volume.

  13. Comparison BIPM.RI(I)-K8 of high dose-rate Ir-192 brachytherapy standards for reference air kerma rate of the VSL and the BIPM

    DEFF Research Database (Denmark)

    Alvarez, J.T.; De Pooter, J.A.; Andersen, Claus E.

    2014-01-01

    An indirect comparison of the standards for reference air kerma rate for 192Ir high dose rate brachytherapy sources of the Dutch Metrology Institute (VSL), The Netherlands, and of the Bureau International des Poids et Mesures (BIPM) was carried out at the VSL in November 2009. The comparison resu...

  14. High dose rate endobronchial brachytherapy: a curative treatment; La curietherapie endobronchique de haut debit de dose: un traitement curatif

    Energy Technology Data Exchange (ETDEWEB)

    Peiffert, D.; Spaeth, D.; Winnefeld, J. [Centre Alexis-Vautrin, 54 - Vandoeuvre-les-Nancy (France); Menard, O. [Centre Hospitalier Universitaire Nancy-Brabois, 54 - Vandoeuvre-les-Nancy (France)

    2000-06-01

    New endobronchial techniques of treatment allow a good unblocking. Nevertheless, only high dose rate brachytherapy delivers a curative treatment for invasive carcinomas. This study analyses the results of the first 33 consecutive patients treated with curative intent by this technique from 1994 to 1997, and followed-up more than one year. Thirty-seven lesions were treated, with usual schedule delivering 30 Gy at 1 cm depth in six fractions and three to five weeks. All the patients were meticulously selected on the local involvement of the tumour and absolute contraindications to a surgical treatment. All of them have a pulmonary disease history or a general contraindication. With a 14-month follow-up, the local control at two months after the treatment was 95 % (endoscopic and histologic), and 90 % of the patients presented a prolonged local control. Four patients died of the treated cancer, another of a controlateral cancer. Ten patients died of another disease, five of them from a respiratory insufficiency. The overall survival rate at two years was 53 % and the specific survival rate 80 %. The acute tolerance was good, without incident. Asymptomatic bronchial stenoses, described by endoscopic follow-up, were described for seven patients. We conclude that, on the basis of a good selection of the patients, and a respect of the indications, high dose rate endobronchial brachytherapy is an effective curative treatment. It offers a new curative option and must be proposed for the small invasive carcinomas in non-operable patients. (author)

  15. A Performance Evaluation of a Notebook PC under a High Dose-Rate Gamma Ray Irradiation Test

    Directory of Open Access Journals (Sweden)

    Jai Wan Cho

    2014-01-01

    Full Text Available We describe the performance of a notebook PC under a high dose-rate gamma ray irradiation test. A notebook PC, which is small and light weight, is generally used as the control unit of a robot system and loaded onto the robot body. Using TEPCO’s CAMS (containment atmospheric monitoring system data, the gamma ray dose rate before and after a hydrogen explosion in reactor units 1–3 of the Fukushima nuclear power plant was more than 150 Gy/h. To use a notebook PC as the control unit of a robot system entering a reactor building to mitigate the severe accident situation of a nuclear power plant, the performance of the notebook PC under such intense gamma-irradiation fields should be evaluated. Under a similar dose-rate (150 Gy/h gamma ray environment, the performances of different notebook PCs were evaluated. In addition, a simple method for a performance evaluation of a notebook PC under a high dose-rate gamma ray irradiation test is proposed. Three notebook PCs were tested to verify the method proposed in this paper.

  16. Total skin electron irradiation therapy in mycosis fungoides using high-dose rate mode: a preliminary experience.

    Science.gov (United States)

    Parida, Dillip K; Verma, Kaushal K; Chander, Subhash; Joshi, R C; Rath, Goura K

    2005-10-01

    Total skin electron irradiation (TSEI) therapy is the treatment of choice for mycosis fungoides. However, conventional TSEI therapy is time consuming as well as patient unfriendly. Therefore we used high-dose rate (HDR) mode TSEI in these patients. High-dose rate mode of TSEI is a technological innovation attached to a Linear Accelerator (Philips, SL-20, Netherlands), which can deliver an electron beam of 30 Gy/min at the iso-center. The iso-center faces the patient, 100 cm away from the target of the linear accelerator. The patient is treated at a distance of 10 feet from the iso-center of the linear accelerator. The dose delivered to the skin was 1.13 Gy/min, making the treatment execution much easier and patient compliance much better. Seven male patients between 40 and 64 years in age having mycosis fungoides for 9-18 months were treated by TSEI using high-dose rate mode between 1998 and 2000. The TSEI was performed according to the Stanford technique, delivering a total dose of 36 Gy. Each patient received a dose of 1.2 Gy/field/day. There were six fields, i.e. anterior, posterior, left and right anterior obliques, and left and right posterior obliques in both the upper and lower parts of the body. The eyes and nails were shielded at each session of radiotherapy. The times taken at each session of the therapy and radiation-associated side-effects were determined in each patient. The patients were followed up to 26 months (median 9 months) to look for any relapse. Three patients had early stage disease (IB) whereas four patients had advanced disease (IIB). Six patients out of these had complete remission following TSEI while one patient died as a result of progression of the disease during treatment. The treatment time taken at each treatment session in each individual patient was approximately 15 min. Radiation-associated morbidity was seen in all patients. Cutaneous lesions relapsed in two patients after 4 and 10 months, respectively, while four patients were

  17. High-dose-rate brachytherapy as salvage modality for locally recurrent prostate cancer after definitive radiotherapy. A systematic review

    Energy Technology Data Exchange (ETDEWEB)

    Chatzikonstantinou, Georgios; Zamboglou, Nikolaos; Roedel, Claus; Tselis, Nikolaos [J.W. Goethe University of Frankfurt, Department of Radiotherapy and Oncology, Frankfurt am Main (Germany); Zoga, Eleni [Sana Klinikum Offenbach, Department of Radiotherapy and Oncology, Offenbach am Main (Germany); Strouthos, Iosif [Medical Center - University of Freiburg, Department of Radiotherapy and Oncology, University of Freiburg, Freiburg (Germany); Butt, Saeed Ahmed [Sana Klinikum Offenbach, Department of Medical Physics and Engineering, Offenbach am Main (Germany)

    2017-09-15

    To review the current status of interstitial high-dose-rate brachytherapy as a salvage modality (sHDR BRT) for locally recurrent prostate cancer after definitive radiotherapy (RT). A literature search was performed in PubMed using ''high-dose-rate, brachytherapy, prostate cancer, salvage'' as search terms. In all, 51 search results published between 2000 and 2016 were identified. Data tables were generated and summary descriptions created. The main outcome parameters used were biochemical control (BC) and toxicity scores. Eleven publications reported clinical outcome and toxicity with follow-up ranging from 4-191 months. A variety of dose and fractionation schedules were described, including 19.0 Gy in 2 fractions up to 42.0 Gy in 6 fractions. The 5-year BC ranged from 18-77%. Late grade 3 genitourinary and gastrointestinal toxicity was 0-32% and 0-5.1%, respectively. sHDR BRT appears as safe and effective salvage modality for the reirradiation of locally recurrent prostate cancer after definitive RT. (orig.) [German] Zusammenfassende Darstellung relevanter Literatur zur interstitiellen High-Dose-Rate-Brachytherapie als Salvage-Modalitaet (sHDR-BRT) bei der Behandlung des lokal rezidivierten Prostatakarzinoms nach vorausgegangener definitiver Radiotherapie (RT). In der PubMed-Datenbank wurde eine Literaturrecherche mit den Suchbegriffen ''high-dose-rate, brachytherapy, prostate cancer, salvage'' durchgefuehrt. Zwischen den Jahren 2000 und 2016 wurden 51 Publikationen identifiziert. Die biochemische Kontrolle (BC) sowie das assoziierte Toxizitaetsprofil waren onkologische Hauptpunkte in der Analyse der beruecksichtigten Literatur. Von onkologischen Ergebnissen und Toxizitaeten berichteten 11 Publikationen bei einer medianen Nachbeobachtungszeit von 4-191 Monaten. Eine Variabilitaet von Dosis- und Fraktionierungsregimen wurde beschrieben mit totalen physikalischen Dosen von 19,0 Gy in 2 Fraktionen bis zu 42,0 Gy in 6 Fraktionen

  18. High-Dose-Rate Brachytherapy for the Treatment of Recalcitrant Keloids: A Unique, Effective Treatment Protocol

    NARCIS (Netherlands)

    van Leeuwen, M.C.E.; Stokmans, S.C.; Bulstra, A.E.J.; Meijer, O.W.M.; van Leeuwen, P.A.M.; Niessen, F.B.

    2014-01-01

    BACKGROUND:: Keloids cause aesthetic disfigurement and physical complaints, mainly pain and pruritus. Treatment of these scars is difficult, with high recurrence rates forming the main issue. Surgical excision with adjuvant radiotherapy is considered the most efficacious treatment. At their

  19. Postoperative single-dose interstitial high-dose-rate brachytherapy in therapy-resistant keloids

    NARCIS (Netherlands)

    Hafkamp, C. J. H.; Lapid, O.; Dávila Fajardo, R.; van de Kar, A. L.; Koedooder, C.; Stalpers, L. J.; Pieters, B. R.

    2017-01-01

    Patients with keloids complain of the cosmetic aspect, pain, and pruritus. Many different therapies are being used for keloids. The aim of this study was to evaluate the recurrence rate and outcome after resection followed by a single-dose brachytherapy. Patients treated by resection of the keloid

  20. External beam radiation and high-dose-rate brachytherapy for elderly patients with gastroesophageal junction adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    2017-07-01

    Full Text Available Purpose: The aim of this study was to retrospectively observe and analyze the long-term treatment outcomes of 96 elderly patients with gastroesophageal junction adenocarcinoma (GEJAC who were treated with californium-252 (252Cf neutron brachytherapy (NBT in combination with external beam radiotherapy (EBRT with or without chemotherapy. Material and methods: From January 2002 to November 2012, 96 patients with GEJAC underwent treatment. The total radiation dose to the reference point via NBT was 8-25 Gy-eq in 2 to 5 fractions, with 1 fraction per week. The total dose via EBRT was 40-54 Gy, which was delivered over a period of 4 to 5.5 weeks with normal fraction. Results: The median survival time for the 96 patients was 15.3 months, and the 1-, 2-, 3-, and 5-year rates of overall survival (OS were 62.5%, 33.7%, 20.1%, and 7.9%, respectively. The 1-, 2-, 3-, and 5-year rates for local-regional control (LRC were 78.7%, 57.9%, 41.8%, and 26.4%, respectively. The patients’ age was an independent factor that was significantly associated with OS (p = 0.006 and LRC (p = 0.0005, according to univariate analysis. The 3-year OS (LRC was 31.9% (62.9% for patients aged 70-74 years and 16.1% (19.5% for patients aged ≥ 75 years. From the time of treatment completion to the development of local-regional recurrence or death, 5 (5.2% patients experienced fistula and 7 (7.3% experienced massive bleeding. Conclusions: The clinical data indicated that NBT in combination with EBRT produced favorable local control and long-term survival rates for elderly patients with GEJAC, and that the side effects were tolerable. The patient’s age could be used to select the appropriate treatment in an elderly patient.

  1. Development of Real-Time Measurement of Effective Dose for High Dose Rate Neutron Fields

    CERN Document Server

    Braby, L A; Reece, W D

    2003-01-01

    Studies of the effects of low doses of ionizing radiation require sources of radiation which are well characterized in terms of the dose and the quality of the radiation. One of the best measures of the quality of neutron irradiation is the dose mean lineal energy. At very low dose rates this can be determined by measuring individual energy deposition events, and calculating the dose mean of the event size. However, at the dose rates that are normally required for biology experiments, the individual events can not be separated by radiation detectors. However, the total energy deposited in a specified time interval can be measured. This total energy has a random variation which depends on the size of the individual events, so the dose mean lineal energy can be calculated from the variance of repeated measurements of the energy deposited in a fixed time. We have developed a specialized charge integration circuit for the measurement of the charge produced in a small ion chamber in typical neutron irradiation exp...

  2. On-Line High Dose-Rate Gamma Ray Irradiation Test of the CCD/CMOS Cameras

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jai Wan; Jeong, Kyung Min [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-05-15

    In this paper, test results of gamma ray irradiation to CCD/CMOS cameras are described. From the CAMS (containment atmospheric monitoring system) data of Fukushima Dai-ichi nuclear power plant station, we found out that the gamma ray dose-rate when the hydrogen explosion occurred in nuclear reactors 1{approx}3 is about 160 Gy/h. If assumed that the emergency response robot for the management of severe accident of the nuclear power plant has been sent into the reactor area to grasp the inside situation of reactor building and to take precautionary measures against releasing radioactive materials, the CCD/CMOS cameras, which are loaded with the robot, serve as eye of the emergency response robot. In the case of the Japanese Quince robot system, which was sent to carry out investigating the unit 2 reactor building refueling floor situation, 7 CCD/CMOS cameras are used. 2 CCD cameras of Quince robot are used for the forward and backward monitoring of the surroundings during navigation. And 2 CCD (or CMOS) cameras are used for monitoring the status of front-end and back-end motion mechanics such as flippers and crawlers. A CCD camera with wide field of view optics is used for monitoring the status of the communication (VDSL) cable reel. And another 2 CCD cameras are assigned for reading the indication value of the radiation dosimeter and the instrument. In the preceding assumptions, a major problem which arises when dealing with CCD/CMOS cameras in the severe accident situations of the nuclear power plant is the presence of high dose-rate gamma irradiation fields. In the case of the DBA (design basis accident) situations of the nuclear power plant, in order to use a CCD/CMOS camera as an ad-hoc monitoring unit in the vicinity of high radioactivity structures and components of the nuclear reactor area, a robust survivability of this camera in such intense gamma-radiation fields therefore should be verified. The CCD/CMOS cameras of various types were gamma irradiated at a

  3. High dose-rate irradiation of materials with pulsed ion beams at NDCX-II

    Science.gov (United States)

    Seidl, Peter; Treffert, F.; Ji, Q.; Ludewigt, B.; Persaud, A.; Kong, X.; de Leon, S. J.; Dowling, E.; Waldron, W. L.; Schenkel, T.; Barnard, J. J.; Friedman, A.; Grote, D. P.; Stepanov, A.; Gilson, E. P.; Kaganovich, I. D.

    2017-10-01

    Charged particle radiation effects in materials is important for the design of fusion plasma facing components. Also, radiation effects in semiconductor devices are of interest for many applications such as detectors and space electronics. We present results from radiation effects studies with intense pulses of helium ions that impinged on thin samples at the induction linac at Berkeley Lab (Neutralized Drift Compression Experiment-II). Intense bunches of 1.2 MeV He+ ions with peak currents of 2 A, 1-mm beam spot radius and 2-30 ns FWHM duration create controlled high instantaneous dose rates enabling the exploration of collective damage effects. We use in-situ diagnostics to monitor transient effects due to rapid heating and the ionization and damage cascade dynamics. For tin, single pulses deposit sufficient energy in the foil to drive phase transitions. A new Thomson parabola to measures ion energy loss and charge state distributions following transmission of a few micron thick samples. In silicon, ion pulses induce free electron densities of order 1021 cm-3. Supported by the Office of Science of the US DOE under contracts DE-AC0205CH11231, DE-AC52-07NA27344 and DE-AC02-09CH11466 and by the China Scholarship Council.

  4. Brachytherapy optimization using radiobiological-based planning for high dose rate and permanent implants for prostate cancer treatment

    Science.gov (United States)

    Seeley, Kaelyn; Cunha, J. Adam; Hong, Tae Min

    2017-01-01

    We discuss an improvement in brachytherapy--a prostate cancer treatment method that directly places radioactive seeds inside target cancerous regions--by optimizing the current standard for delivering dose. Currently, the seeds' spatiotemporal placement is determined by optimizing the dose based on a set of physical, user-defined constraints. One particular approach is the ``inverse planning'' algorithms that allow for tightly fit isodose lines around the target volumes in order to reduce dose to the patient's organs at risk. However, these dose distributions are typically computed assuming the same biological response to radiation for different types of tissues. In our work, we consider radiobiological parameters to account for the differences in the individual sensitivities and responses to radiation for tissues surrounding the target. Among the benefits are a more accurate toxicity rate and more coverage to target regions for planning high-dose-rate treatments as well as permanent implants.

  5. Clinicopathologic Comparison of High-Dose-Rate Endorectal Brachytherapy versus Conventional Chemoradiotherapy in the Neoadjuvant Setting for Resectable Stages II and III Low Rectal Cancer

    Directory of Open Access Journals (Sweden)

    Jessica A. Smith

    2012-01-01

    Full Text Available Purpose. To assess for differences in clinical, radiologic, and pathologic outcomes between patients with stage II-III rectal adenocarcinoma treated neoadjuvantly with conventional external beam radiotherapy (3D conformal radiotherapy (3DRT or intensity-modulated radiotherapy (IMRT versus high-dose-rate endorectal brachytherapy (EBT. Methods. Patients undergoing neoadjuvant EBT received 4 consecutive daily 6.5 Gy fractions without chemotherapy, while those undergoing 3DRT or IMRT received 28 daily 1.8 Gy fractions with concurrent 5-fluorouracil. Data was collected prospectively for 7 EBT patients and retrospectively for 25 historical 3DRT/IMRT controls. Results. Time to surgery was less for EBT compared to 3DRT and IMRT (P<0.001. There was a trend towards higher rate of pathologic CR for EBT (P=0.06. Rates of margin and lymph node positivity at resection were similar for all groups. Acute toxicity was less for EBT compared to 3DRT and IMRT (P=0.025. Overall and progression-free survival were noninferior for EBT. On MRI, EBT achieved similar complete response rate and reduction in tumor volume as 3DRT and IMRT. Histopathologic comparison showed that EBT resulted in more localized treatment effects and fewer serosal adhesions. Conclusions. EBT offers several practical benefits over conventional radiotherapy techniques and appears to be at least as effective against low rectal cancer as measured by short-term outcomes.

  6. Low and high dose rate heavy ion radiation-induced intestinal and colonic tumorigenesis in APC1638N/+ mice

    Science.gov (United States)

    Suman, Shubhankar; Kumar, Santosh; Moon, Bo-Hyun; Fornace, Albert J.; Datta, Kamal

    2017-05-01

    Ionizing radiation (IR) is a recognized risk factor for colorectal cancer (CRC) and astronauts undertaking long duration space missions are expected to receive IR doses in excess of permissible limits with implications for colorectal carcinogenesis. Exposure to IR in outer space occurs at low doses and dose rates, and energetic heavy ions due to their high linear energy transfer (high-LET) characteristics remain a major concern for CRC risk in astronauts. Previously, we have demonstrated that intestinal tumorigenesis in a mouse model (APC1638N/+) of human colorectal cancer was significantly higher after exposure to high dose rate energetic heavy ions relative to low-LET γ radiation. The purpose of the current study was to compare intestinal tumorigenesis in APC1638N/+ mice after exposure to energetic heavy ions at high (50 cGy/min) and relatively low (0.33 cGy/min) dose rate. Male and female mice (6-8 weeks old) were exposed to either 10 or 50 cGy of 28Si (energy: 300 MeV/n; LET: 70 keV/μm) or 56Fe (energy: 1000 MeV/n; LET: 148 keV/μm) ions at NASA Space Radiation Laboratory in Brookhaven National Laboratory. Mice (n = 20 mice/group) were euthanized and intestinal and colon tumor frequency and size were counted 150 days after radiation exposure. Intestinal tumorigenesis in male mice exposed to 56Fe was similar for high and low dose rate exposures. Although male mice showed a decreasing trend at low dose rate relative to high dose rate exposures, the differences in tumor frequency between the two types of exposures were not statistically significant after 28Si radiation. In female mice, intestinal tumor frequency was similar for both radiation type and dose rates tested. In both male and female mice intestinal tumor size was not different after high and low dose rate radiation exposures. Colon tumor frequency in male and female mice after high and low dose rate energetic heavy ions was also not significantly different. In conclusion, intestinal and colonic tumor

  7. Investigations of DNA damage induction and repair resulting from cellular exposure to high dose-rate pulsed proton beams

    Energy Technology Data Exchange (ETDEWEB)

    Renis, M.; Malfa, G.; Tomasello, B. [Drug Sciences Department, University of Catania, Catania (Italy); Borghesi, M.; Schettino, G. [Queen' s University Belfast, Northern Ireland (United Kingdom); Favetta, M.; Romano, F.; Cirrone, G. A. P. [National Institute for Nuclear Physics (INFN-LNS), Catania (Italy); Manti, L. [Physics Science Department, University of Naples Federico II, Naples, and National Institute for Nuclear Physics (INFN), Naples (Italy)

    2013-07-26

    Studies regarding the radiobiological effects of low dose radiation, microbeam irradiation services have been developed in the world and today laser acceleration of protons and heavy ions may be used in radiation therapy. The application of different facilities is essential for studying bystander effects and relating signalling phenomena in different cells or tissues. In particular the use of ion beams results advantageous in cancer radiotherapy compared to more commonly used X-rays, since the ability of ions in delivering lethal amount of doses into the target tumour avoiding or limiting damage to the contiguous healthy tissues. At the INFN-LNS in Catania, a multidisciplinary radiobiology group is strategically structured aimed to develop radiobiological research, finalised to therapeutic applications, compatible with the use of high dose laser-driven ion beams. The characteristic non-continuous dose rates with several orders of magnitude of laser-driven ion beams makes this facility very interesting in the cellular systems' response to ultra-high dose rates with non-conventional pulse time intervals cellular studies. Our group have projected to examine the effect of high dose laser-driven ion beams on two cellular types: foetal fibroblasts (normal control cells) and DU145 (prostate cancer cells), studying the modulation of some different bio-molecular parameters, in particular cell proliferation and viability, DNA damage, redox cellular status, morphological alterations of both the cytoskeleton components and some cell organelles and the possible presence of apoptotic or necrotic cell death. Our group performed preliminary experiments with high energy (60 MeV), dose rate of 10 Gy/min, doses of 1, 2, 3 Gy and LET 1 keV/μm on human foetal fibroblasts (control cells). We observed that cell viability was not influenced by the characteristics of the beam, the irradiation conditions or the analysis time. Conversely, DNA damage was present at time 0, immediately

  8. Investigations of DNA damage induction and repair resulting from cellular exposure to high dose-rate pulsed proton beams

    Science.gov (United States)

    Renis, M.; Borghesi, M.; Favetta, M.; Malfa, G.; Manti, L.; Romano, F.; Schettino, G.; Tomasello, B.; Cirrone, G. A. P.

    2013-07-01

    Studies regarding the radiobiological effects of low dose radiation, microbeam irradiation services have been developed in the world and today laser acceleration of protons and heavy ions may be used in radiation therapy. The application of different facilities is essential for studying bystander effects and relating signalling phenomena in different cells or tissues. In particular the use of ion beams results advantageous in cancer radiotherapy compared to more commonly used X-rays, since the ability of ions in delivering lethal amount of doses into the target tumour avoiding or limiting damage to the contiguous healthy tissues. At the INFN-LNS in Catania, a multidisciplinary radiobiology group is strategically structured aimed to develop radiobiological research, finalised to therapeutic applications, compatible with the use of high dose laser-driven ion beams. The characteristic non-continuous dose rates with several orders of magnitude of laser-driven ion beams makes this facility very interesting in the cellular systems' response to ultra-high dose rates with non-conventional pulse time intervals cellular studies. Our group have projected to examine the effect of high dose laser-driven ion beams on two cellular types: foetal fibroblasts (normal control cells) and DU145 (prostate cancer cells), studying the modulation of some different bio-molecular parameters, in particular cell proliferation and viability, DNA damage, redox cellular status, morphological alterations of both the cytoskeleton components and some cell organelles and the possible presence of apoptotic or necrotic cell death. Our group performed preliminary experiments with high energy (60 MeV), dose rate of 10 Gy/min, doses of 1, 2, 3 Gy and LET 1 keV/μm on human foetal fibroblasts (control cells). We observed that cell viability was not influenced by the characteristics of the beam, the irradiation conditions or the analysis time. Conversely, DNA damage was present at time 0, immediately

  9. Development and evaluation of an automatic interstitial catheter digitization tool for adaptive high-dose-rate brachytherapy.

    Science.gov (United States)

    Dise, Joseph; Liang, Xing; Scheuermann, Joshua; Anamalayil, Shibu; Mesina, Carmen; Lin, Lilie L; Teo, Boon-Keng Kevin

    2015-01-01

    To develop and evaluate an automatic interstitial catheter digitization algorithm for use in adaptive high-dose-rate brachytherapy for gynecologic cancers using the Syed-Neblett template. We developed an automatic catheter digitization tool, which uses a region growing algorithm in conjunction with a spline model of the catheters. Seed locations were selected in each catheter for the region growing algorithm. The region growing was constrained by a spline model of the catheters, which prevents intercatheter crossover or incorrect digitization due to air pockets. Plan reoptimization was performed on successive day computed tomography scans using dwell positions for the Day 1 computed tomography. This method was applied to 10 patients who had received high-dose-rate interstitial brachytherapy using the Syed-Neblett template. The prescribed dose was 18.75 or 20 Gy delivered in five fractions, twice daily, and more than 3 consecutive days. Dosimetric comparisons were made between automatically and manually digitized plans. The region growing algorithm was able to successfully digitize all catheters. The mean difference between automatic and manually digitized positions was 0.4 ± 0.2 mm. No significant difference was found in dosimetric parameters between the automatic and manually digitized plans. The mean D90% of the clinical target volume over all 3 days of treatment of the manual vs. reoptimized automatic plans was 94.3 ± 6.58% and 92.32 ± 8.34%, respectively (p = 0.50). The algorithm discussed in this article is the first developed for adaptive interstitial brachytherapy for a large number of catheters (14 on average). The algorithm has future potential in digitization quality assurance. A region growing algorithm was developed to automatically digitize interstitial catheters in high-dose-rate brachytherapy. This automatic digitization tool was shown to be accurate compared with manual digitization. Copyright © 2015 American Brachytherapy Society

  10. Perioperative Interstitial High-Dose-Rate Brachytherapy for the Treatment of Recurrent Keloids: Feasibility and Early Results

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Ping, E-mail: ping.jiang@uksh.de [Department of Radiation Oncology, University Clinic Schleswig-Holstein, Campus Kiel, Kiel (Germany); Baumann, René [Department of Radiation Oncology, University Clinic Schleswig-Holstein, Campus Kiel, Kiel (Germany); Dunst, Juergen [Department of Radiation Oncology, University Clinic Schleswig-Holstein, Campus Kiel, Kiel (Germany); Department of Radiation Oncology, University of Copenhagen, Copenhagen (Denmark); Geenen, Matthias [Department of Reconstructive Surgery, Lubinus Clinic Kiel, Kiel (Germany); Siebert, Frank-André [Department of Radiation Oncology, University Clinic Schleswig-Holstein, Campus Kiel, Kiel (Germany); Niehoff, Peter [Department of Radiation Oncology, University Clinic Schleswig-Holstein, Campus Kiel, Kiel (Germany); Department of Radiation Oncology, Community Clinic Köln, Köln (Germany); Department of Radiation Oncology, University Witten/Herdecke, Witten (Germany); Bertolini, Julia; Druecke, Daniel [Department of Reconstructive Surgery, University Clinic Schleswig-Holstein, Campus Kiel, Kiel (Germany)

    2016-03-01

    Purpose: To prospectively evaluate high-dose-rate brachytherapy in the treatment of therapy-resistant keloids and report first results, with emphasis on feasibility and early treatment outcome. Methods and Materials: From 2009 to 2014, 24 patients with 32 recurrent keloids were treated with immediate perioperative high-dose-rate brachytherapy; 3 patients had been previously treated with adjuvant external beam radiation therapy and presented with recurrences in the pretreated areas. Two or more different treatment modalities had been tried in all patients and had failed to achieve remission. After (re-)excision of the keloids, a single brachytherapy tube was placed subcutaneously before closing the wound. The target volume covered the scar in total length. Brachytherapy was given in 3 fractions with a single dose of 6 Gy in 5 mm tissue depth. The first fraction was given within 6 hours after surgery, the other 2 fractions on the first postoperative day. Thus, a total dose of 18 Gy in 3 fractions was administered within 36 hours after the resection. Results: The treatment was feasible in all patients. No procedure-related complications (eg, secondary infections) occurred. Nineteen patients had keloid-related symptoms before treatment like pain and pruritus; disappearance of symptoms was noticed in all patients after treatment. After a median follow-up of 29.4 months (range, 7.9-72.4 months), 2 keloid recurrences and 2 mildly hypertrophied scars were observed. The local control rate was 94%. Pigmentary abnormalities were detected in 3 patients, and an additional 6 patients had a mild delay in the wound-healing process. Conclusions: The early results of this study prove the feasibility and the efficacy of brachytherapy for the prevention of keloids. The results also suggest that brachytherapy may be advantageous in the management of high-risk keloids or as salvage treatment for failure after external beam therapy.

  11. Perioperative high-dose-rate interstitial brachytherapy combined with external beam radiation therapy for soft tissue sarcoma.

    Science.gov (United States)

    Sharma, Daya Nand; Deo, S V Suryanarayana; Rath, Goura Kisor; Shukla, Nootan Kumar; Bakhshi, Sameer; Gandhi, Ajeet Kumar; Julka, Pramod Kumar

    2015-01-01

    The aim of our study was to evaluate the role of perioperative high-dose-rate interstitial brachytherapy (PHDRIBT) in combination with external beam radiation therapy (EBRT) in patients with localized soft tissue sarcoma (STS). From year 2004 to 2010, 52 patients with localized STS were treated with wide local excision plus PHDRIBT followed by EBRT. Median size of the tumor was 8 cm (range, 4-19 cm). A single-plane interstitial brachytherapy implant with an average of nine catheters was performed during the surgical resection. The PHDRIBT was started on third postoperative day to deliver a high-dose-rate dose of 16 Gy in four fractions over 2 days using twice-a-day fractionation schedule. After 4 weeks, EBRT was started for a prescription dose of 50 Gy by conventional fractionation. Subsequently, chemotherapy was administered, if indicated as per our institutional policy. Patients were followed up regularly to study local control, survival, and toxicity. At a median followup of 46 months, no patient developed local recurrence, but 12 patients developed distant metastases. The 5-year overall survival and disease-free survival were 67% and 63%, respectively. Main acute toxicity was delayed wound healing observed in 3 patients (5.7%). Commonest late toxicity was chronic skin/subcutaneous fibrosis noticed in 5 patients (9.6%). The PHDRIBT combined with EBRT provides excellent local control and survival rates with acceptable acute and late toxicity in patients with localized STS. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  12. Two-piece customized mold technique for high-dose-rate brachytherapy on cancers of the buccal mucosa and lip.

    Science.gov (United States)

    Matsuzaki, Hidenobu; Takemoto, Mitsuhiro; Hara, Marina; Unetsubo, Teruhisa; Yanagi, Yoshinobu; Katsui, Kuniaki; Katayama, Norihisa; Yoshio, Kotaro; Takenobu, Toshihiko; Kuroda, Masahiro; Kanazawa, Susumu; Asaumi, Jun-Ichi

    2012-01-01

    High-dose-rate (HDR) brachytherapy using a customized mold is a minimally invasive treatment for oral cancer; however, it is difficult to use this technique for buccal and lip cancers involving the commissura labiorum, owing to its anatomic form. The purpose of this study was to introduce an improved customized mold consisting of 2 pieces to allow the fixation of molds to these sites. Five patients with buccal carcinoma and 1 patient with lip carcinoma were treated with this technique after external beam radiotherapy. One patient with neck metastasis underwent both neck dissection and partial tumor resection before HDR brachytherapy. At the end of the follow-up period, 5 patients had no tumor recurrence, and 1 patient had suffered local recurrence. Our technique is a viable therapeutic option for patients with buccal and lip carcinomas for whom the therapeutic modalities are limited by age, performance status, and other factors. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Applicator Attenuation Effect on Dose Calculations of Esophageal High-Dose Rate Brachytherapy Using EDR2 Film

    Directory of Open Access Journals (Sweden)

    Seyed Mohsen Hosseini Daghigh

    2012-03-01

    Full Text Available Introduction Interaluminal brachytherapy is one of the important methods of esophageal cancer treatment. The effect of applicator attenuation is not considered in dose calculation method released by AAPM-TG43. In this study, the effect of High-Dose Rate (HDR brachytherapy esophageal applicator on dose distribution was surveyed in HDR brachytherapy. Materials and Methods A cylindrical PMMA phantom was built in order to be inserted by various sizes of esophageal applicators. EDR2 films were placed at 33 mm from Ir-192 source and irradiated with 1.5 Gy after planning using treatment planning system for all applicators. Results The results of film dosimetry in reference point for 6, 8, 10, and 20 mm applicators were 1.54, 1.53, 1.48, and 1.50 Gy, respectively. The difference between practical and treatment planning system results was 0.023 Gy (

  14. Interstitial brachytherapy for carcinoma of the base of tongue using a high dose rate {sup 192}Ir remote afterloader

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Tetsuo; Imai, Michiko; Iijima, Mitsuharu; Suzuki, Kazunori; Nozue, Masashi; Kaneko, Masao; Mukodaka, Hiroyuki; Asai, Yoshihiro [Hamamatsu Univ., Shizuoka (Japan). School of Medicine

    1996-11-01

    We have applied an interstitial brachytherapy employing a high dose rate {sup 192}Ir remote afterloader to five patients with cancer of the base of tongue since December 1994. Insertion of applicators was carried out with tracheotomy under general anesthesia. Brachytherapy was delivered twice a day with a 6-hour interval. Irradiation dose was estimated at the point of 5 mm from outer applicators. HDR brachytherapy was well tolerated for 4-5 days in all patients and acute radiation reaction was minimal. Local control were observed in two cases. In conclusion, our preliminary experience suggests that HDR brachytherapy may be an option in the radiotherapy for carcinoma of the base of tongue. Optimal dose-fractionation protocol should be established. (author)

  15. Automated construction of an intraoperative high-dose-rate treatment plan library for the Varian brachytherapy treatment planning system.

    Science.gov (United States)

    Deufel, Christopher L; Furutani, Keith M; Dahl, Robert A; Haddock, Michael G

    2016-01-01

    The ability to create treatment plans for intraoperative high-dose-rate (IOHDR) brachytherapy is limited by lack of imaging and time constraints. An automated method for creation of a library of high-dose-rate brachytherapy plans that can be used with standard planar applicators in the intraoperative setting is highly desirable. Nonnegative least squares algebraic methods were used to identify dwell time values for flat, rectangular planar applicators. The planar applicators ranged in length and width from 2 cm to 25 cm. Plans were optimized to deliver an absorbed dose of 10 Gy to three different depths from the patient surface: 0 cm, 0.5 cm, and 1.0 cm. Software was written to calculate the optimized dwell times and insert dwell times and positions into a .XML plan template that can be imported into the Varian brachytherapy treatment planning system. The user may import the .XML template into the treatment planning system in the intraoperative setting to match the patient applicator size and prescribed treatment depth. A total of 1587 library plans were created for IOHDR brachytherapy. Median plan generation time was approximately 1 minute per plan. Plan dose was typically 100% ± 1% (mean, standard deviation) of the prescribed dose over the entire length and width of the applicator. Plan uniformity was best for prescription depths of 0 cm and 0.5 cm from the patient surface. An IOHDR plan library may be created using automated methods. Thousands of plan templates may be optimized and prepared in a few hours to accommodate different applicator sizes and treatment depths and reduce treatment planning time. The automated method also enforces dwell time symmetry for symmetrical applicator geometries, which simplifies quality assurance. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  16. Electromagnetic tracking for catheter reconstruction in ultrasound-guided high-dose-rate brachytherapy of the prostate.

    Science.gov (United States)

    Bharat, Shyam; Kung, Cynthia; Dehghan, Ehsan; Ravi, Ananth; Venugopal, Niranjan; Bonillas, Antonio; Stanton, Doug; Kruecker, Jochen

    2014-01-01

    The accurate delivery of high-dose-rate brachytherapy is dependent on the correct identification of the position and shape of the treatment catheters. In many brachytherapy clinics, transrectal ultrasound (TRUS) imaging is used to identify the catheters. However, manual catheter identification on TRUS images can be time consuming, subjective, and operator dependent because of calcifications and distal shadowing artifacts. We report the use of electromagnetic (EM) tracking technology to map the position and shape of catheters inserted in a tissue-mimicking phantom. The accuracy of the EM system was comprehensively quantified using a three-axis robotic system. In addition, EM tracks acquired from catheters in a phantom were compared with catheter positions determined from TRUS and CT images to compare EM system performance to standard clinical imaging modalities. The tracking experiments were performed in a controlled laboratory environment and also in a typical brachytherapy operating room to test for potential EM distortions. The robotic validation of the EM system yielded a mean accuracy of brachytherapy operating room. The achievable accuracy depends to a large extent on the calibration of the TRUS probe, geometry of the tracked devices relative to the EM field generator, and locations of surrounding clinical equipment. To address the issue of variable accuracy, a robust calibration algorithm has been developed and integrated into the workflow. The proposed mapping technique was also found to improve the workflow efficiency of catheter identification. The high baseline accuracy of the EM system, the consistent agreement between EM-tracked, TRUS- and CT-identified catheters, and the improved workflow efficiency illustrate the potential value of using EM tracking for catheter mapping in high-dose-rate brachytherapy. Copyright © 2014 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  17. Experimental Platform for Ultra-high Dose Rate FLASH Irradiation of Small Animals Using a Clinical Linear Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Schüler, Emil; Trovati, Stefania; King, Gregory; Lartey, Frederick; Rafat, Marjan; Villegas, Manuel; Praxel, A. Joe [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Loo, Billy W., E-mail: BWLoo@stanford.edu [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California (United States); Maxim, Peter G., E-mail: PMaxim@stanford.edu [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California (United States)

    2017-01-01

    Purpose: A key factor limiting the effectiveness of radiation therapy is normal tissue toxicity, and recent preclinical data have shown that ultra-high dose rate irradiation (>50 Gy/s, “FLASH”) potentially mitigates this effect. However, research in this field has been strongly limited by the availability of FLASH irradiators suitable for small animal experiments. We present a simple methodologic approach for FLASH electron small animal irradiation with a clinically available linear accelerator (LINAC). Methods and Materials: We investigated the FLASH irradiation potential of a Varian Clinac 21EX in both clinical mode and after tuning of the LINAC. We performed detailed FLUKA Monte Carlo and experimental dosimetric characterization at multiple experimental locations within the LINAC head. Results: Average dose rates of ≤74 Gy/s were achieved in clinical mode, and the dose rate after tuning exceeded 900 Gy/s. We obtained 220 Gy/s at 1-cm depth for a >4-cm field size with 90% homogeneity throughout a 2-cm-thick volume. Conclusions: We present an approach for using a clinical LINAC for FLASH irradiation. We obtained dose rates exceeding 200 Gy/s after simple tuning of the LINAC, with excellent dosimetric properties for small animal experiments. This will allow for increased availability of FLASH irradiation to the general research community.

  18. High-dose isotretinoin treatment and the rate of retrial, relapse, and adverse effects in patients with acne vulgaris.

    Science.gov (United States)

    Blasiak, Rachel C; Stamey, Christopher R; Burkhart, Craig N; Lugo-Somolinos, Aida; Morrell, Dean S

    2013-12-01

    Isotretinoin is the most effective treatment for acne. The ideal dosing regimen is unknown. To determine the rates of relapse of acne vulgaris and retrial of isotretinoin after high cumulative-dose treatment and the changes to the adverse effect profile. A prospective, observational, intervention study was conducted from August 1, 2008, to August 31, 2010, in a single academic tertiary care center with multiple providers. A total of 180 patients with acne resistant to other treatments were enrolled. Of these, 116 participated in the 12-month follow-up survey, for a response rate of 64.4%. Patients received isotretinoin, with dosing based on the providers' judgment. Patients were divided into 2 groups on the basis of cumulative dosing (treatment with a prescription topical or oral acne medication after a course of isotretinoin) or retrial (retreatment with isotretinoin) at 12-month follow-up and adverse effects experienced during and after 12 months of treatment. RESULTS The mean age of the participants was 19.3 years, 51.9% were female, and 74.1% were white. At 12 months' follow-up, 97.4% of the patients reported that their acne was improved. Overall, acne in 32.7% of patients in the study relapsed at 12 months, and 1.72% of the patients required a retrial. In the lower-dose treatment group (treatment groups developed cheilitis and xerosis during treatment. Retinoid dermatitis was significantly more common in the high-dose treatment group (53.8% vs 31.6%; P = .02). None of the other adverse effects was significantly different between the 2 groups. The dosing regimen used in the present study is considerably higher than that used in previous studies of isotretinoin. At 1 year after completion of isotretinoin treatment, we found that patients receiving 220 mg/kg or more had a significantly decreased risk of relapse. Rash was the only adverse effect that was significantly more common in the high-dose group during treatment. This study suggests that significantly

  19. Radiobiological equivalent of low/high dose rate brachytherapy and evaluation of tumor and normal responses to the dose.

    Science.gov (United States)

    Manimaran, S

    2007-06-01

    The aim of this study was to compare the biological equivalent of low-dose-rate (LDR) and high-dose-rate (HDR) brachytherapy in terms of the more recent linear quadratic (LQ) model, which leads to theoretical estimation of biological equivalence. One of the key features of the LQ model is that it allows a more systematic radiobiological comparison between different types of treatment because the main parameters alpha/beta and micro are tissue-specific. Such comparisons also allow assessment of the likely change in the therapeutic ratio when switching between LDR and HDR treatments. The main application of LQ methodology, which focuses on by increasing the availability of remote afterloading units, has been to design fractionated HDR treatments that can replace existing LDR techniques. In this study, with LDR treatments (39 Gy in 48 h) equivalent to 11 fractions of HDR irradiation at the experimental level, there are increasing reports of reproducible animal models that may be used to investigate the biological basis of brachytherapy and to help confirm theoretical predictions. This is a timely development owing to the nonavailability of sufficient retrospective patient data analysis. It appears that HDR brachytherapy is likely to be a viable alternative to LDR only if it is delivered without a prohibitively large number of fractions (e.g., fewer than 11). With increased scientific understanding and technological capability, the prospect of a dose equivalent to HDR brachytherapy will allow greater utilization of the concepts discussed in this article.

  20. Assessment for effects and adverse effects of preoperative high-dose-rate intraluminal brachytherapy for lower rectal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Terauchi, Kazuo (Hyogo College of Medicine, Nishinomiya (Japan))

    1993-11-01

    Endoscopic and histological effects and perianal dermal side effects after high-dose-rate intraluminal brachytherapy (HDRIBT) using [sup 60]Co for preoperative irradiation were assessed in thirty-five patients with low-lying rectal cancers. In more than half of the patients irradiated with 30 Gy or more, marked effective change was observed under endoscopy. In the histological assessment, while the resected lesions irradiated with 16-20 Gy showed no effective change, 68.8%, 75.0%, and 76.9% respectively, of those in the groups given 30 Gy, 40-60 Gy, and 80 Gy showed marked destruction. While 23. 1% of the patients irradiated with 80 Gy developed severe perianal dermal lesions requiring surgical removal of the anus, 18.8% of the 30 Gy group and 25% of the 40-60 Gy group suffered from dermal side effects which were mild and reversible. Consequently, it has been concluded that the proper regimen for preoperative HDRIBT for rectal cancer was 30 Gy followed by surgery within two weeks. During the follow up period from 35 to 70 months, one patient (2.9%) who received 16 Gy HDRIBT developed local recurrence within 3 years after resection, and the other one developed hepatic metastasis. The 3-year local recurrence rate after resection for lower rectal cancer in the previous series at our department was 19.6%. We, therefore, concluded that HDRIBT was a promising adjuvant therapy for rectal cancer. (author).

  1. Needle migration and dosimetric impact in high-dose-rate brachytherapy for prostate cancer evaluated by repeated MRI.

    Science.gov (United States)

    Buus, Simon; Lizondo, Maria; Hokland, Steffen; Rylander, Susanne; Pedersen, Erik M; Tanderup, Kari; Bentzen, Lise

    To quantify needle migration and dosimetric impact in high-dose-rate brachytherapy for prostate cancer and propose a threshold for needle migration. Twenty-four high-risk prostate cancer patients treated with an HDR boost of 2 × 8.5 Gy were included. Patients received an MRI for planning (MRI1), before (MRI2), and after treatment (MRI3). Time from needle insertion to MRI3 was ∼3 hours. Needle migration was evaluated from coregistered images: MRI1-MRI2 and MRI1-MRI3. Dose volume histogram parameters from the treatment plan based on MRI1 were related to parameters based on needle positions in MRI2 or MRI3. Regression was used to model the average needle migration per implant and change in D90 clinical target volume, CTV prostate+3mm . The model fit was used for estimating the dosimetric impact in equivalent dose in 2 Gy fractions for dose levels of 6, 8.5, 10, 15, and 19 Gy. Needle migration was on average 2.2 ± 1.8 mm SD from MRI1-MRI2 and 5.0 ± 3.0 mm SD from MRI1-MRI3. D90 CTV prostate+3mm was robust toward average needle migration ≤3 mm, whereas for migration >3 mm D90 decreased by 4.5% per mm. A 3 mm of needle migration resulted in a decrease of 0.9, 1.7, 2.3, 4.8, and 7.6 equivalent dose in 2 Gy fractions for dose levels of 6, 8.5, 10, 15, and 19 Gy, respectively. Substantial needle migration in high-dose-rate brachytherapy occurs frequently in 1-3 hours following needle insertion. A 3-mm threshold of needle migration is proposed, but 2 mm may be considered for dose levels ≥15 Gy. Copyright © 2017 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  2. Parallelized patient-specific quality assurance for high-dose-rate image-guided brachytherapy in an integrated computed tomography-on-rails brachytherapy suite.

    Science.gov (United States)

    Kim, Taeho; Showalter, Timothy N; Watkins, W Tyler; Trifiletti, Daniel M; Libby, Bruce

    2015-01-01

    To describe a parallelized patient-specific quality assurance (QA) program designed to ensure safety and quality in image-guided high-dose-rate brachytherapy in an integrated computed tomography (CT)-on-rails brachytherapy suite. A patient-specific QA program has been modified for the image-guided brachytherapy (IGBT) program in an integrated CT-on-rails brachytherapy suite. In the modification of the QA procedures of Task Group-59, the additional patient-specific QA procedures are included to improve rapid IGBT workflow with applicator placement, imaging, planning, treatment, and applicator removal taking place in one room. The IGBT workflow is partitioned into two groups of tasks that can be performed in parallel by two or more staff members. One of the unique components of our implemented workflow is that groups work together to perform QA steps in parallel and in series during treatment planning and contouring. Coordinating efforts in this systematic way enable rapid and safe brachytherapy treatment while incorporating 3-dimensional anatomic variations between treatment days. Implementation of these patient-specific QA procedures in an integrated CT-on-rails brachytherapy suite ensures confidence that a rapid workflow IGBT program can be implemented without sacrificing patient safety or quality and deliver highly-conformal dose to target volumes. These patient-specific QA components may be adapted to other IGBT environments that seek to provide rapid workflow while ensuring quality. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  3. Single-fraction high-dose-rate brachytherapy and hypofractionated external beam radiation therapy in the treatment of intermediate-risk prostate cancer - long term results.

    Science.gov (United States)

    Cury, Fabio L; Duclos, Marie; Aprikian, Armen; Patrocinio, Horacio; Kassouf, Wassim; Shenouda, George; Faria, Sergio; David, Marc; Souhami, Luis

    2012-03-15

    We present the long-term results of a cohort of patients with intermediate-risk prostate cancer (PC) treated with single-fraction high-dose-rate brachytherapy (HDRB) combined with hypofractionated external beam radiation therapy (HypoRT). Patients were treated exclusively with HDRB and HypoRT. HDRB delivered a dose of 10 Gy to the prostate surface and HypoRT consisted of 50 Gy delivered in 20 daily fractions. The first 121 consecutive patients with a minimum of 2 years posttreatment follow-up were assessed for toxicity and disease control. The median follow-up was 65.2 months. No acute Grade III or higher toxicity was seen. Late Grade II gastrointestinal toxicity was seen in 9 patients (7.4%) and Grade III in 2 (1.6%). Late Grade III genitourinary toxicity was seen in 2 patients (1.6%). After a 24-month follow-up, a rebiopsy was offered to the first 58 consecutively treated patients, and 44 patients agreed with the procedure. Negative biopsies were found in 40 patients (91%). The 5-year biochemical relapse-free survival rate was 90.7% (95% CI, 84.5-96.9%), with 13 patients presenting biochemical failure. Among them, 9 were diagnosed with distant metastasis. Prostate cancer-specific and overall survival rates at 5 years were 100% and 98.8% (95% CI, 96.4-100%), respectively. The combination of HDRB and HypoRT is well tolerated, with acceptable toxicity rates. Furthermore, results from rebiopsies revealed an encouraging rate of local control. These results confirm that the use of conformal RT techniques, adapted to specific biological tumor characteristics, have the potential to improve the therapeutic ratio in intermediate-risk PC patients. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. High-dose-rate interstitial brachytherapy for T1-T2-stage penile carcinoma: short-term results.

    Science.gov (United States)

    Sharma, Daya Nand; Joshi, Nikhil P; Gandhi, Ajeet Kumar; Haresh, Kunhi P; Gupta, Subhash; Julka, Pramod Kumar; Rath, Goura Kisor

    2014-01-01

    Interstitial brachytherapy (IBT) is a preferred treatment option over partial penectomy in selected patients with T1-T2-stage penile carcinoma because of its organ preservation ability. Literature is mostly based on the use of low-dose-rate IBT, and experience with high-dose-rate (HDR) IBT is extremely limited. We studied the role of HDR-IBT alone in patients with T1-T2-stage penile carcinoma. Between April 2010 and July 2013, 14 patients with T1-T2-stage penile carcinoma were treated with HDR-IBT at our center. Size of the primary lesion ranged from 1.5 to 4.0cm. A two-to-four-plane free-hand implant was performed using plastic catheters. The prescribed dose of HDR-IBT was 42-51Gy in 14-17 fractions using twice-a-day fractionation schedule. Patients were followed up regularly for assessment of local control, survival, toxicity, and sexual function. At a median followup of 22 months, 2 patients developed recurrent disease at locoregional site. The 3-year overall survival was 83% with penis preservation rate of 93%. All patients developed acute Grade III skin toxicity that healed during 6-8-weeks time. Urethral stenosis and soft tissue necrosis was not seen in any of the patients. A total of 4 patients experienced mild asymptomatic fibrosis in the implanted area. Around 10 patients had satisfactory sexual function status at the last followup visit. Although it was a small sample size, our results have demonstrated excellent local control rate and acceptable toxicity with HDR-IBT in patients with T1-T2-stage penile carcinoma. Copyright © 2014 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  5. Global convergence analysis of fast multiobjective gradient-based dose optimization algorithms for high-dose-rate brachytherapy.

    Science.gov (United States)

    Lahanas, M; Baltas, D; Giannouli, S

    2003-03-07

    We consider the problem of the global convergence of gradient-based optimization algorithms for interstitial high-dose-rate (HDR) brachytherapy dose optimization using variance-based objectives. Possible local minima could lead to only sub-optimal solutions. We perform a configuration space analysis using a representative set of the entire non-dominated solution space. A set of three prostate implants is used in this study. We compare the results obtained by conjugate gradient algorithms, two variable metric algorithms and fast-simulated annealing. For the variable metric algorithm BFGS from numerical recipes, large fluctuations are observed. The limited memory L-BFGS algorithm and the conjugate gradient algorithm FRPR are globally convergent. Local minima or degenerate states are not observed. We study the possibility of obtaining a representative set of non-dominated solutions using optimal solution rearrangement and a warm start mechanism. For the surface and volume dose variance and their derivatives, a method is proposed which significantly reduces the number of required operations. The optimization time, ignoring a preprocessing step, is independent of the number of sampling points in the planning target volume. Multiobjective dose optimization in HDR brachytherapy using L-BFGS and a new modified computation method for the objectives and derivatives has been accelerated, depending on the number of sampling points, by a factor in the range 10-100.

  6. The American Brachytherapy Society Treatment Recommendations for Locally Advanced Carcinoma of the Cervix Part II: High Dose-Rate Brachytherapy

    Science.gov (United States)

    Viswanathan, Akila N.; Beriwal, Sushil; De Los Santos, Jennifer; Demanes, D. Jeffrey; Gaffney, David; Hansen, Jorgen; Jones, Ellen; Kirisits, Christian; Thomadsen, Bruce; Erickson, Beth

    2012-01-01

    Purpose This report presents the 2011 update to the American Brachytherapy Society (ABS) high-dose-rate (HDR) brachytherapy guidelines for locally advanced cervical cancer. Methods Members of the American Brachytherapy Society (ABS) with expertise in cervical cancer brachytherapy formulated updated guidelines for HDR brachytherapy using tandem and ring, ovoids, cylinder or interstitial applicators for locally advanced cervical cancer were revised based on medical evidence in the literature and input of clinical experts in gynecologic brachytherapy. Results The Cervical Cancer Committee for Guideline Development affirms the essential curative role of tandem-based brachytherapy in the management of locally advanced cervical cancer. Proper applicator selection, insertion, and imaging are fundamental aspects of the procedure. Three-dimensional imaging with magnetic resonance or computed tomography or radiographic imaging may be used for treatment planning. Dosimetry must be performed after each insertion prior to treatment delivery. Applicator placement, dose specification and dose fractionation must be documented, quality assurance measures must be performed, and follow-up information must be obtained. A variety of dose/fractionation schedules and methods for integrating brachytherapy with external-beam radiation exist. The recommended tumor dose in 2 Gray (Gy) per fraction radiobiologic equivalence (EQD2) is 80–90 Gy, depending on tumor size at the time of brachytherapy. Dose limits for normal tissues are discussed. Conclusion These guidelines update those of 2000 and provide a comprehensive description of HDR cervical cancer brachytherapy in 2011. PMID:22265437

  7. Needle migration and dosimetric impact in high-dose-rate brachytherapy for prostate cancer evaluated by repeated MRI

    DEFF Research Database (Denmark)

    Buus, Simon; Lizondo, Maria; Hokland, Steffen

    2017-01-01

    PURPOSE: To quantify needle migration and dosimetric impact in high-dose-rate brachytherapy for prostate cancer and propose a threshold for needle migration. METHODS AND MATERIALS: Twenty-four high-risk prostate cancer patients treated with an HDR boost of 2 × 8.5 Gy were included. Patients...... received an MRI for planning (MRI1), before (MRI2), and after treatment (MRI3). Time from needle insertion to MRI3 was ∼3 hours. Needle migration was evaluated from coregistered images: MRI1-MRI2 and MRI1-MRI3. Dose volume histogram parameters from the treatment plan based on MRI1 were related...... to parameters based on needle positions in MRI2 or MRI3. Regression was used to model the average needle migration per implant and change in D90 clinical target volume, CTVprostate+3mm. The model fit was used for estimating the dosimetric impact in equivalent dose in 2 Gy fractions for dose levels of 6, 8.5, 10...

  8. In-Containment Signal Conditioning and Transmission via Power Lines within High Dose Rate Areas of Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Steffen; Weigel, Robert; Koelpin, Alexander [Institute for Electronics Engineering, University of Erlangen-Nuremberg, Cauerstr. 9, 91058 Erlangen (Germany); Dennerlein, Juergen; Janke, Iryna; Weber, Johannes [AREVA GmbH, Paul-Gossen-Str. 100, 91052 Erlangen (Germany)

    2015-07-01

    Signal conditioning and transmission for sensor systems and networks within the containment of nuclear power plants (NPPs) still poses a challenge to engineers, particularly in the case of equipment upgrades for existing plants, temporary measurements, decommissioning of plants, but also for new builds. This paper presents an innovative method for efficient and cost-effective instrumentation within high dose rate areas inside the containment. A transmitter-receiver topology is proposed that allows simultaneous, unidirectional point-to-point transmission of multiple sensor signals by superimposing them on existing AC or DC power supply cables using power line communication (PLC) technology. Thereby the need for costly installation of additional cables and containment penetrations is eliminated. Based on commercial off-the-shelf (COTS) electronic parts, a radiation hard transmitter is designed to operate in harsh environment within the containment during full plant operation. Hardware modularity of the transmitter allows application specific tradeoffs between redundancy and channel bandwidth. At receiver side in non-radiated areas, signals are extracted from the power line, demodulated, and provided either in analog or digital output format. Laboratory qualification tests and field test results within a boiling water reactor (BWR) are validating the proof of concept of the proposed system. (authors)

  9. Comparison of treatment planning on dosimetric differences between 192Ir sources for high-dose rate brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Oh Nam [Dept. of Radiology, Mokpo Science University, Mokpo (Korea, Republic of); Shin, Seong Soo; Ahn, Woo Sang; KIm, Dae Yong; Choi, Won Sik [Dept. of Radiation Oncology, Gangenung Asan Hospital, University of Ulsan College of Medicine, Gangenung (Korea, Republic of); Kwon, Kyung Tae [Dept. of Radiologic Technology, Dongam Health University, Suwon (Korea, Republic of); Lim, Cheong Hwan [Dept. of Radiological Science, Hanseo University, Seosan (Korea, Republic of); Lee, Sang Ho [Dept. of Radiological Science, Seonam University, Namwon (Korea, Republic of)

    2016-06-15

    To evaluate whether the difference in geometrical characteristics between high-dose-rate (HDR) 192Ir sources would influence the dose distributions of intracavitary brachytherapy. Two types of microSelectron HDR 192Ir sources (classic and new models) were selected in this study. Two-dimensional (2D) treatment plans for classic and new sources were generated by using PLATO treatment planning system. We compared the point A, point B, and bladder and rectum reference points based on ICRU 38 recommendation. The radial dose function of the new source agrees with that of the classic source except difference of up to 2.6% at the nearest radial distance. The differences of anisotropy functions agree within 2% for r=1, 3, and 5 cm and 20°<θ<165°. The largest discrepancies of anisotropy functions reached up to 27% for θ<20° at r=0.25 cm and were up to 13%, 10%, and 7% at r=1, 3, and 5 cm for θ>170°, respectively. There were no significant differences in doses of point A, point B, and bladder point for the treatment plans between the new and classic sources. For the ICRU rectum point, the percent dose difference was on average 0.65% and up to 1.0%. The dose discrepancies between two treatment plans are mainly affected due to the geometrical difference of the source and the sealed capsule.

  10. American Brachytherapy Task Group Report: A pooled analysis of clinical outcomes for high-dose-rate brachytherapy for cervical cancer.

    Science.gov (United States)

    Mayadev, Jyoti; Viswanathan, Akila; Liu, Yu; Li, Chin-Shang; Albuquerque, Kevin; Damato, Antonio L; Beriwal, Sushil; Erickson, Beth

    Advanced imaging used in combination with brachytherapy (BT) has revolutionized the treatment of patients with cervical cancer. We present a comprehensive review of the literature for definitive radiation with high-dose-rate (HDR) BT. In addition, we investigate potential outcome improvement with image-based brachytherapy (IBBT) compared to studies using traditional Point A dosing. This review extensively investigates acute and late toxicities. This study reviews the literature from 2000 to 2015 with an emphasis on modern approaches including concurrent chemotherapy (chemoRT), radiation, and HDR BT and IBBT. Descriptive statistics and pelvic control (PC), disease-free survival (DFS), and overall survival (OS) outcomes were calculated using weighted means to report pooled analysis of outcomes. Literature search yielded 16 prospective, 51 retrospective studies that reported survival outcomes, and 13 retrospective studies that focused on acute and late toxicity outcomes regardless of applicator type. There are 57 studies that report Point A dose specification with 33 having chemoRT, and 10 studies that use IBBT, 8 with chemoRT. Patients receiving radiation and chemoRT with HDR BT in the prospective studies, with >24 months followup, rates of PC were: for RT: 73%, SD: 11; CRT: 82%, SD: 8; DFS-RT: 55%, SD: 10; CRT: 65%, SD: 7; OS-RT: 66%, SD: 7; CRT: 70%, SD: 11. In the retrospective studies, the PC rates (weighted means) for the radiation and chemoradiation outcomes are 75% vs. 80%, and for DFS, the values were 55% vs. 63%, respectively. Comparing patients receiving chemoRT and IBBT to traditional Point A dose specification, there is a significant improvement in PC (p Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  11. High-dose-rate intraoperative brachytherapy (IOHDR) using flab technique in the treatment of soft tissue sarcomas

    Energy Technology Data Exchange (ETDEWEB)

    Rachbauer, F.; Sununu, T.; Bach, C.; Nogler, M.; Krismer, M. [Dept. of Orthopedics, Univ. of Innsbruck (Austria); Sztankay, A.; Eichberger, P.; Schiestl, B.; Lukas, P. [Dept. of Radiotherapy-Radiooncology, Univ. of Innsbruck (Austria); Kreczy, A. [Inst. of Pathologic Anatomy, Univ. of Innsbruck (Austria)

    2003-07-01

    Background: Adjuvant radiotherapy has been shown to improve local control in patients with soft tissue sarcoma. Additional brachytherapy represents a means of enhancing the therapeutic ratio, as biological and dosimetric advantage over single external-beam irradiation (EBRT) can be expected. High-dose-rate intraoperative brachytherapy (IOHDR) as a boost therapy should therefore be able to further diminish the rate of local recurrence even when performing marginal resection. There are sparse data on IOHDR using flab applicators as adjuvant boost to EBRT in combination with marginal resection of soft tissue sarcomas. Patients and Methods: Within a period of 8 years, we prospectively studied 39 adult patients treated by marginal resection, IOHDR using the flab technique and EBRT for soft tissue sarcomas. There were 32 high-grade and seven low-grade tumors, 35 were > 5 cm. Mean follow-up was 26 months (range 3-59 months). Results: We could not detect any local recurrences. No treatment-related loss of limb or life occurred. There were no neurologic or vascular complications, all patients maintained functioning extremities as evidenced by a mean musculoskeletal tumor society (MSTS) functional score of 88.5 (70-100). Treatment-related wound morbidity occurred in eleven patients necessitating revision surgery in eight. Metastatic disease developed in seven patients, six of them had died. The 2-year actuarial disease-free survival was 84%. Conclusions: IOHDR using the flab technique in combination with EBRT and marginal resection is an efficient treatment technique leading to optimal local control rates and limited functional impairment. (orig.)

  12. High-Dose-Rate Brachytherapy Boost Effect on Local Tumor Control in Young Women With Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Guinot, Jose-Luis, E-mail: jguinot@fivo.org [Department of Radiation Oncology, Fundacion Instituto Valenciano de Oncologia, Valencia (Spain); Baixauli-Perez, Cristobal [Health Services Research Unit, Center for Public Health Research, Valencia (Spain); Soler, Pablo; Tortajada, Maria Isabel; Moreno, Araceli; Santos, Miguel Angel; Mut, Alejandro [Department of Radiation Oncology, Fundacion Instituto Valenciano de Oncologia, Valencia (Spain); Gozalbo, Francisco [Department of Pathology, Fundacion Instituto Valenciano de Oncologia, Valencia (Spain); Arribas, Leoncio [Department of Radiation Oncology, Fundacion Instituto Valenciano de Oncologia, Valencia (Spain)

    2015-01-01

    Purpose: To evaluate the local control rate and complications of a single fraction of high-dose-rate brachytherapy (HDR BT) boost in women aged 45 yeas and younger after breast-conserving therapy. Methods and Materials: Between 1999 and 2007, 167 patients between the ages of 26 and 45 years old (72 were 40 years old or younger), with stages T1 to T2 invasive breast cancer with disease-free margin status of at least 5 mm after breast-conserving surgery received 46 to 50 Gy whole-breast irradiation plus a 7-Gy HDR-BT boost (“fast boost”). An axillary dissection was performed in 72.5% of the patients and sentinel lymph node biopsy in 27.5%. A supraclavicular area was irradiated in 19% of the patients. Chemotherapy was used in 86% of the patients and hormone treatment in 77%. Clinical nodes were present in 18% and pathological nodes in 29%. The pathological stage was pT0: 5%, pTis: 3%, pT1: 69% and pT2: 23%. Intraductal component was present in 40% and 28% were G3. Results: At a median follow-up of 92 months, 9 patients relapsed on the margin of the implant, and 1 patient in another quadrant, resulting in a 10-year local relapse rate of 4.3% and a breast relapse rate of 4.9%, with breast preservation in 93.4%; no case of mastectomy due to poor cosmesis arose. Actuarial 5- and 10-year disease-free, cause-specific, and overall survival rates were 87.9% and 85.8%, and 92.1% and 88.4%, and 92.1% and 87.3%, respectively. In a univariate analysis, triple-negative cases and negative hormone receptors did worse, but in a multivariate analysis, only the last factor was significant for local and breast control. Asymptomatic fibrosis G2 was recorded in 3 cases, and there were no other late complications. Cosmetic results were good to excellent in 97% of cases. Conclusions: A single dose of 7 Gy using the fast-boost technique is well tolerated, with a low rate of late complications and improved local tumor control in women aged 45 and younger, compared to published data

  13. Absorbed dose simulations in near-surface regions using high dose rate Iridium-192 sources applied for brachytherapy

    Science.gov (United States)

    Moura, E. S.; Zeituni, C. A.; Sakuraba, R. K.; Gonçalves, V. D.; Cruz, J. C.; Júnior, D. K.; Souza, C. D.; Rostelato, M. E. C. M.

    2014-02-01

    Brachytherapy treatment with Iridium-192 high dose rate (HDR) sources is widely used for various tumours and it could be developed in many anatomic regions. Iridium-192 sources are inserted inside or close to the region that will be treated. Usually, the treatment is performed in prostate, gynaecological, lung, breast and oral cavity regions for a better clinical dose coverage compared with other techniques, such as, high energy photons and Cobalt-60 machines. This work will evaluate absorbed dose distributions in near-surface regions around Ir-192 HDR sources. Near-surface dose measurements are a complex task, due to the contribution of beta particles in the near-surface regions. These dose distributions should be useful for non-tumour treatments, such as keloids, and other non-intracavitary technique. For the absorbed dose distribution simulations the Monte Carlo code PENELOPE with the general code penEasy was used. Ir-192 source geometry and a Polymethylmethacrylate (PMMA) tube, for beta particles shield were modelled to yield the percentage depth dose (PDD) on a cubic water phantom. Absorbed dose simulations were realized at the central axis to yield the Ir-192 dose fall-off along central axis. The results showed that more than 99.2% of the absorbed doses (relative to the surface) are deposited in 5 cm depth but with slower rate at higher distances. Near-surface treatments with Ir-192 HDR sources yields achievable measurements and with proper clinical technique and accessories should apply as an alternative for treatment of lesions where only beta sources were used.

  14. High-dose rate brachytherapy as monotherapy in prostate cancer: A systematic review of its safety and efficacy.

    Science.gov (United States)

    Sánchez-Gómez, L M; Polo-deSantos, M; Rodríguez-Melcón, J I; Angulo, J C; Luengo-Matos, S

    2017-03-01

    High-dose rate brachytherapy (HDR-BT) is an increasingly popular treatment for patients with localised prostate cancer (PC). To assess the safety and efficacy of HDR-BT as monotherapy in PC. A systematic literature review was conducted through searches on MEDLINE (PubMed), Cochrane Library, CDR, ClinicalTrials and EuroScan. We assessed safety and efficacy indicators. We selected 2 reviews and 12 uncontrolled studies, included in these 2 reviews. In terms of efficacy, local control in 6 studies was 97-100%. The biochemical progression-free survival varied as follows: 85-100% for low risk and 79-92% for high risk. Survival free of metastases was >95% at 8 years, except in one study where the survival rate was 87% at 5 years. The overall survival was ≥95% in 8 studies. In terms of safety, most of the studies recorded acute and long-term genitourinary and gastrointestinal complications, especially grade ≥2. Only 3 studies found grade 4 complications. All studies, except for one without complications, observed genitourinary complications that were more frequent and severe than the gastrointestinal complications. Two studies assessed the quality of life and showed an initial reduction in various domains and subsequent partial or total recovery, except in the sexual domain. HDR-BT is effective as monotherapy, especially in cases of low to intermediate risk. There is insufficient information on high-risk patients. The short to medium-term toxicity was acceptable. Further research needs to be funded to provide more information on the long-term safety and efficacy of this treatment. Copyright © 2016 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

  15. Extrascleral extension of choroidal melanoma: post-enucleation high-dose-rate interstitial brachytherapy of the orbit.

    Science.gov (United States)

    Finger, Paul T; Tena, Lawrence B; Semenova, Ekaterina; Aridgides, Paul; Choi, Walter H

    2014-01-01

    To investigate if orbital extension of uveal melanoma can be treated with high-dose-rate (HDR) brachytherapy. This study is a retrospective analysis of the results of a clinical case series was performed on 10 patients. Each underwent primary enucleation for uveal melanoma, was discovered to have orbital extension, and consented for HDR brachytherapy. By American Joint Committee on Cancer (AJCC) initial tumor grading, there was one each (T1c, T2c, T2d, and T3d, three T4c, and two T4d-staged uveal melanomas. One was AJCC-staged R2 due to orbital recurrence presenting 16 months after enucleation. (192)Ir HDR brachytherapy involved transcutaneous circumferential orbital incisions allowing for evenly spaced brachytherapy catheters into the orbit. A target dose of 32.85 Gy (range, 32.85-34 Gy) was delivered in 9-10 twice-daily fractions (range, 3.4-3.65 Gy per fraction) over 5 consecutive days. Data analysis included but was not limited to radiation therapy methods, local tumor control, side effects, and metastatic rate. In the 9 patients who tolerated treatment, there has been no orbital recurrence at a median follow-up of 18 months (range, 1-62 months). Four patients died of metastatic disease (one presented with a treated solitary liver metastasis before brachytherapy). There was no significant eyelash or eyebrow loss. There was no radiation-induced eyelid erythema, orbital infection, or contracted sockets. All orbits accepted and maintained ocular prostheses. Brachytherapy was used as an alternative to external beam radiation treatment for postenucleation orbital melanoma. This series reports complete local control, few side effects, and excellent cosmetic results. Copyright © 2014 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  16. High-Dose-Rate Interstitial Brachytherapy as Monotherapy for Clinically Localized Prostate Cancer: Treatment Evolution and Mature Results

    Energy Technology Data Exchange (ETDEWEB)

    Zamboglou, Nikolaos [Department of Radiation Oncology, Klinikum Offenbach, Offenbach (Germany); Tselis, Nikolaos, E-mail: ntselis@hotmail.com [Department of Radiation Oncology, Klinikum Offenbach, Offenbach (Germany); Baltas, Dimos [Department of Medical Physics and Engineering, Klinikum Offenbach, Offenbach (Germany); Buhleier, Thomas [Department of Radiation Oncology, Klinikum Offenbach, Offenbach (Germany); Martin, Thomas [Department of Radiation Oncology, Klinikum Bremen-Mitte, Bremen (Germany); Milickovic, Natasa; Papaioannou, Sokratis [Department of Medical Physics and Engineering, Klinikum Offenbach, Offenbach (Germany); Ackermann, Hanns [Institute of Biostatistics, J.W. Goethe University of Frankfurt, Frankfurt (Germany); Tunn, Ulf W. [Department of Urology, Klinikum Offenbach, Offenbach (Germany)

    2013-03-01

    Purpose: To report the clinical outcome of high-dose-rate (HDR) interstitial (IRT) brachytherapy (BRT) as sole treatment (monotherapy) for clinically localized prostate cancer. Methods and Materials: Between January 2002 and December 2009, 718 consecutive patients with clinically localized prostate cancer were treated with transrectal ultrasound (TRUS)-guided HDR monotherapy. Three treatment protocols were applied; 141 patients received 38.0 Gy using one implant in 4 fractions of 9.5 Gy with computed tomography-based treatment planning; 351 patients received 38.0 Gy in 4 fractions of 9.5 Gy, using 2 implants (2 weeks apart) and intraoperative TRUS real-time treatment planning; and 226 patients received 34.5 Gy, using 3 single-fraction implants of 11.5 Gy (3 weeks apart) and intraoperative TRUS real-time treatment planning. Biochemical failure was defined according to the Phoenix consensus, and toxicity was evaluated using Common Toxicity Criteria for Adverse Events version 3. Results: The median follow-up time was 52.8 months. The 36-, 60-, and 96-month biochemical control and metastasis-free survival rates for the entire cohort were 97%, 94%, and 90% and 99%, 98%, and 97%, respectively. Toxicity was scored per event, with 5.4% acute grade 3 genitourinary and 0.2% acute grade 3 gastrointestinal toxicity. Late grade 3 genitourinary and gastrointestinal toxicities were 3.5% and 1.6%, respectively. Two patients developed grade 4 incontinence. No other instance of grade 4 or greater acute or late toxicity was reported. Conclusion: Our results confirm IRT-HDR-BRT is safe and effective as monotherapy for clinically localized prostate cancer.

  17. Image-Guided High-Dose-Rate (HDR) Boost Localization Using MRI/MR Spectroscopy: A Correlation Study with Biopsy.

    Science.gov (United States)

    Vigneault, Eric; Mbodji, Khaly; Racine, Louis G; Chevrette, Eric; Lavallee, Marie C; Martin, André-Guy; Despres, Philippe; Beaulieu, Luc

    2016-09-21

    The purpose of this study is to compare the blind interpretations of magnetic resonance imaging (MRI) sequences, diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC), mapping, and magnetic resonance spectroscopy (MRS) of the prostate, in comparison to prostate biopsy to identify a valid dominant intraprostatic lesion (DIL) for dose escalation using high-dose rate brachytherapy. MRI/MRS were performed on 20 patients with intermediate risk adenocarcinoma of the prostate. T1W, T2W, DWI-ADC, and MRS sequences were performed at 1.5 T with pelvic and endorectal coils. An experienced radiologist rated the presence of cancer in each sextant by using a dichotomic approach, first on MR standard acquisitions (T1W and T2W), then on DWI-ADC mapping, and later on MRS images. Areas under the receiver's operating characteristic curve were calculated using a sextant as the unit of analysis. The transrectal ultrasonography-guided biopsy results were used as the reference standard. A table summarizing the MRI/MRS findings was made and compared to the corresponding area in the prostate biopsy report. A perfect match was defined to be the presence of cancer in the same sextant of the MRI/MRS exam and the prostate biopsy. The interpretation of the MRI/MRS exams per sextant was compared to the diagnostic biopsy report. MRI readings were compared with the biopsy as a surrogate for the complete pathology specimen of the prostate. A sensitivity (Sn) of 98.6% (95% confidence interval, 92.2% - 99.9%) and specificity (Sp) of 60.8% (46.1% - 74.2%) were found. The positive and negative predictive values (PPV, NPV) were 77.3% (67.1% - 85.5%) and 96.9% (83.8% - 99.9%), respectively. When MRS readings were compared with biopsy, we found a Sn of 96.4% (87.7% - 99.6%) and Sp of 54.8% (38.7% - 70.2%). The PPV and NPV were 74% (62.4% - 83.6%) and 92% (74% - 99%), respectively. DWI-ADC mapping results were also compared with biopsy. We found a Sn and Sp of 93.7% (84.5% - 98.2%) and 82

  18. Dose-Rate Dependence of High-Dose Health Effects in Humans from Photon Radiation with Application to Radiological Terrorism

    Energy Technology Data Exchange (ETDEWEB)

    Strom, Daniel J.

    2005-01-14

    In 1981, as part of a symposium entitled ''The Control of Exposure of the Public to Ionizing Radiation in the Event of Accident or Attack,'' Lushbaugh, H?bner, and Fry published a paper examining ''radiation tolerance'' of various human health endpoints as a function of dose rate. This paper may not have received the notice it warrants. The health endpoints examined by Lushbaugh et al. were the lethal dose that will kill 50% of people within 60 days of exposure without medical care (LD50/60); severe bone marrow damage in healthy men; severe bone marrow damage in leukemia patients; temporary sterility (azoospermia); reduced male fertility; and late effects such as cancer. Their analysis was grounded in extensive clinical experience and anchored to a few selected data points, and based on the 1968 dose-rate dependence theory of J.L. Bateman. The Lushbaugh et al. paper did not give predictive equations for the relationships, although they were implied in the text, and the relationships were presented in a non-intuitive way. This work derives the parameters needed in Bateman's equation for each health endpoint, tabulates the results, and plots them in a more conventional manner on logarithmic scales. The results give a quantitative indication of how the human organism can tolerate more radiation dose when it is delivered at lower dose rates. For example, the LD50/60 increases from about 3 grays (300 rads) when given at very high dose rates to over 10 grays (1,000 rads) when given at much lower dose rates over periods of several months. The latter figure is borne out by the case of an individual who survived for at least 19 years after receiving doses in the range of 9 to 17 grays (900-1700 rads) over 106 days. The Lushbaugh et al. work shows the importance of sheltering when confronted with long-term exposure to radiological contamination such as would be expected from a radiological dispersion event, reactor accident, or

  19. Design and characterization of a new high-dose-rate brachytherapy Valencia applicator for larger skin lesions.

    Science.gov (United States)

    Candela-Juan, C; Niatsetski, Y; van der Laarse, R; Granero, D; Ballester, F; Perez-Calatayud, J; Vijande, J

    2016-04-01

    The aims of this study were (i) to design a new high-dose-rate (HDR) brachytherapy applicator for treating surface lesions with planning target volumes larger than 3 cm in diameter and up to 5 cm in size, using the microSelectron-HDR or Flexitron afterloader (Elekta Brachytherapy) with a (192)Ir source; (ii) to calculate by means of the Monte Carlo (MC) method the dose distribution for the new applicator when it is placed against a water phantom; and (iii) to validate experimentally the dose distributions in water. The penelope2008 MC code was used to optimize dwell positions and dwell times. Next, the dose distribution in a water phantom and the leakage dose distribution around the applicator were calculated. Finally, MC data were validated experimentally for a (192)Ir mHDR-v2 source by measuring (i) dose distributions with radiochromic EBT3 films (ISP); (ii) percentage depth-dose (PDD) curve with the parallel-plate ionization chamber Advanced Markus (PTW); and (iii) absolute dose rate with EBT3 films and the PinPoint T31016 (PTW) ionization chamber. The new applicator is made of tungsten alloy (Densimet) and consists of a set of interchangeable collimators. Three catheters are used to allocate the source at prefixed dwell positions with preset weights to produce a homogenous dose distribution at the typical prescription depth of 3 mm in water. The same plan is used for all available collimators. PDD, absolute dose rate per unit of air kerma strength, and off-axis profiles in a cylindrical water phantom are reported. These data can be used for treatment planning. Leakage around the applicator was also scored. The dose distributions, PDD, and absolute dose rate calculated agree within experimental uncertainties with the doses measured: differences of MC data with chamber measurements are up to 0.8% and with radiochromic films are up to 3.5%. The new applicator and the dosimetric data provided here will be a valuable tool in clinical practice, making treatment of

  20. Design and characterization of a new high-dose-rate brachytherapy Valencia applicator for larger skin lesions

    Energy Technology Data Exchange (ETDEWEB)

    Candela-Juan, C., E-mail: ccanjuan@gmail.com [Radiation Oncology Department, La Fe University and Polytechnic Hospital, Valencia 46026, Spain and National Dosimetry Centre (CND), Valencia 46009 (Spain); Niatsetski, Y. [Elekta Brachytherapy, Veenendaal 3905 TH (Netherlands); Laarse, R. van der [Quality Radiation Therapy BV, Zeist 3707 HB (Netherlands); Granero, D. [Department of Radiation Physics, ERESA, Hospital General Universitario, Valencia 46014 (Spain); Ballester, F. [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100 (Spain); Perez-Calatayud, J. [Radiation Oncology Department, La Fe University and Polytechnic Hospital, Valencia 46026, Spain and Department of Radiotherapy, Clínica Benidorm, Benidorm 03501 (Spain); Vijande, J. [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100, Spain and Instituto de Física Corpuscular (UV-CSIC), Burjassot 46100 (Spain)

    2016-04-15

    Purpose: The aims of this study were (i) to design a new high-dose-rate (HDR) brachytherapy applicator for treating surface lesions with planning target volumes larger than 3 cm in diameter and up to 5 cm in size, using the microSelectron-HDR or Flexitron afterloader (Elekta Brachytherapy) with a {sup 192}Ir source; (ii) to calculate by means of the Monte Carlo (MC) method the dose distribution for the new applicator when it is placed against a water phantom; and (iii) to validate experimentally the dose distributions in water. Methods: The PENELOPE2008 MC code was used to optimize dwell positions and dwell times. Next, the dose distribution in a water phantom and the leakage dose distribution around the applicator were calculated. Finally, MC data were validated experimentally for a {sup 192}Ir mHDR-v2 source by measuring (i) dose distributions with radiochromic EBT3 films (ISP); (ii) percentage depth–dose (PDD) curve with the parallel-plate ionization chamber Advanced Markus (PTW); and (iii) absolute dose rate with EBT3 films and the PinPoint T31016 (PTW) ionization chamber. Results: The new applicator is made of tungsten alloy (Densimet) and consists of a set of interchangeable collimators. Three catheters are used to allocate the source at prefixed dwell positions with preset weights to produce a homogenous dose distribution at the typical prescription depth of 3 mm in water. The same plan is used for all available collimators. PDD, absolute dose rate per unit of air kerma strength, and off-axis profiles in a cylindrical water phantom are reported. These data can be used for treatment planning. Leakage around the applicator was also scored. The dose distributions, PDD, and absolute dose rate calculated agree within experimental uncertainties with the doses measured: differences of MC data with chamber measurements are up to 0.8% and with radiochromic films are up to 3.5%. Conclusions: The new applicator and the dosimetric data provided here will be a valuable

  1. Prostate gland edema after single-fraction high-dose rate brachytherapy before external beam radiation therapy.

    Science.gov (United States)

    Cury, Fabio L; Duclos, Marie; Aprikian, Armen; Patrocinio, Horacio; Souhami, Luis

    2010-01-01

    High-dose rate brachytherapy (HDRB) is frequently used as a boost to external beam radiation therapy (EBRT) in prostate cancer patients. With the increasing use of small planning target volume margins in EBRT, prostatic edema induced by HDRB can be a contributing factor to geometric miss when HDRB is performed before or during EBRT. We assessed prostate gland volumetric change after single-fraction HDRB and its impact on definition of treatment volume for EBRT. Thirty-one consecutive patients with intermediate-risk prostate cancer treated with single-fraction HDRB (10 Gy) combined with hypofractionated EBRT were analyzed. A second CT scan was performed 7 days after HDRB, and images were coregistered with the planning CT scan that contained the original clinical target volume (CTV). The post-HDRB prostate CTV volume was compared with the original CTV by a single observer. All patients presented volumetric variation. In most cases (68%), the prostate increased in volume, whereas it decreased in 32%. The mean prostatic volume was 42.2 cc before HDRB and 43.6 cc after HDRB, representing a mean volume difference of 3.4%, ranging from -14.2% to 23.8% (p=0.756). This difference is the result of mean changes of 0.6mm (-6.1 to 6.6) in the anterior-posterior, 0.5mm (-5.5 to 3.0) in the lateral, and 0.2mm (-5.0 to 5.0) in the superior-inferior axes. Although a nonsignificant volumetric change occurs after single-fraction HDRB, individual variations on specific axis could lead to important uncertainties during EBRT. (c) 2010. Published by Elsevier Inc.

  2. SU-E-T-428: Class Solution for Prostate High Dose Rate Brachytherapy with Inverse Planning Simulated Annealing.

    Science.gov (United States)

    Sheth, N; Mistry, N; Chen, Y; Yang, C

    2012-06-01

    To develop and validate a class solution for inverse planning simulated annealing (IPSA) with CT based prostate high dose rate brachytherapy (HDR). Between November 2008 and November 2011, our institution treated 40 prostate cancer patients with HDR in 7 Gy fractions followed by external beam radiotherapy. The HDR treatments were planned with Nucletron Oncentra using manual graphical optimization (GO). Plans were optimized to the following clinical goals: = 95% of prostate volume received 7 Gy, plans were manually customized using IPSA (MC-IPSA) for each patient to match prostate coverage by the prescription dose to within ± 1% of the GO plans while meeting the rectal and urethral dose constraints. An IPSA class solution (CS-IPSA) was created from the mean MC-IPSA parameters. New plans were developed for each of these 40 patients using only CS-IPSA with no further optimization. Additionally, plans were created on an independent dataset of 30 different patients using only CS-IPSA with no further optimization. Plans were optimized in about 30 minutes using GO, MC-IPSA took an average of 14.1 ± 6.5 minutes, and CS-IPSA optimizationwas 0.05) among the optimization methods for all clinical goals over the 40 CS-IPSA source patients. There was no significant difference (p > 0.05) between the source and the independent datasets for all clinical goals when using CS-IPSA with no further optimization. A prostate HDR IPSA class solution was developed and validated on a source and an independent dataset. The IPSA class solution yields plans comparable to custom manual IPSA and graphical optimization while saving considerable time. © 2012 American Association of Physicists in Medicine.

  3. The influence of a rectal ultrasound probe on the separation between prostate and rectum in high-dose-rate brachytherapy.

    Science.gov (United States)

    Rylander, Susanne; Buus, Simon; Bentzen, Lise; Pedersen, Erik Morre; Tanderup, Kari

    2015-01-01

    The aim of this study was to compare the distance between prostate and rectum as well as rectal dose-volume histogram (DVH) parameters for high-dose-rate (HDR) prostate brachytherapy (BT) with and without a transrectal ultrasound (US) probe in place during delivery. The study included 20 patients with high-risk prostate cancer treated consecutively with combined external beam radiotherapy (EBRT) and MRI-based HDR-BT. The MRI-based HDR-BT dose plan and prostate gland contour were transferred to the US images after rigid MRI/US coregistration, followed by delineation of the rectum on US images acquired with a transrectal US probe. The prostate-rectum separation was estimated at the apex, reference, and base plane on the US (with rectal probe) and MR images (without rectal probe). Rectal DVH parameters for EBRT + HDR-BT given in equivalent 2 Gy fractionation doses were estimated and compared for US-based and MRI-based HDR-BT dose planning. The median (and range) prostate-rectum separation increased on MR images (without rectal probe) as compared with on US images (with rectal probe) by 10 mm (-5, 18) at the base, 1 mm (-2, 3) at the reference and decreased at the apex by 2 mm (-5, 11). The rectal D5.0cm3, D2.0cm3, and D0.1cm3 decreased by a median of 4 Gy (-1, 10), 4 Gy (-2, 13), and 7 Gy (-4, 26), respectively. MRI-based HDR-BT without a rectal US probe in place as compared with US-based BT with the probe in place demonstrated a significant increase in the prostate-rectum separation, with a potential of reducing rectal dose. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  4. Rotational IMRT delivery using a digital linear accelerator in very high dose rate 'burst mode'

    Energy Technology Data Exchange (ETDEWEB)

    Salter, Bill J; Sarkar, Vikren; Wang, Brian; Szegedi, Martin; Rassiah-Szegedi, Prema [Department of Radiation Oncology, University of Utah, Salt Lake City, UT (United States); Shukla, Himanshu, E-mail: bill.salter@hci.utah.edu [Oncology Care Systems Group, Siemens Medical Solutions (USA), 4040 Nelson Avenue, Concord, CA (United States)

    2011-04-07

    Recently, there has been a resurgence of interest in arc-based IMRT, through the use of 'conventional' multileaf collimator (MLC) systems that can treat large tumor volumes in a single, or very few pass(es) of the gantry. Here we present a novel 'burst mode' modulated arc delivery approach, wherein 2000 monitor units per minute (MU min{sup -1}) high dose rate bursts of dose are facilitated by a flattening-filter-free treatment beam on a Siemens Artiste (Oncology Care Systems, Siemens Medical Solutions, Concord, CA, USA) digital linear accelerator in a non-clinical configuration. Burst mode delivery differs from continuous mode delivery, used by Elekta's VMAT (Elekta Ltd, Crawley, UK) and Varian's RapidArc (Varian Medical Systems, Palo Alto, CA, USA) implementations, in that dose is not delivered while MLC leaves are moving. Instead, dose is delivered in bursts over very short arc angles and only after an MLC segment shape has been completely formed and verified by the controller. The new system was confirmed to be capable of delivering a wide array of clinically relevant treatment plans, without machine fault or other delivery anomalies. Dosimetric accuracy of the modulated arc platform, as well as the Prowess (Prowess Inc., Concord, CA, USA) prototype treatment planning version utilized here, was quantified and confirmed, and delivery times were measured as significantly brief, even with large hypofractionated doses. The burst mode modulated arc approach evaluated here appears to represent a capable, accurate and efficient delivery approach.

  5. Optimization for high-dose-rate brachytherapy of cervical cancer with adaptive simulated annealing and gradient descent.

    Science.gov (United States)

    Yao, Rui; Templeton, Alistair K; Liao, Yixiang; Turian, Julius V; Kiel, Krystyna D; Chu, James C H

    2014-01-01

    To validate an in-house optimization program that uses adaptive simulated annealing (ASA) and gradient descent (GD) algorithms and investigate features of physical dose and generalized equivalent uniform dose (gEUD)-based objective functions in high-dose-rate (HDR) brachytherapy for cervical cancer. Eight Syed/Neblett template-based cervical cancer HDR interstitial brachytherapy cases were used for this study. Brachytherapy treatment plans were first generated using inverse planning simulated annealing (IPSA). Using the same dwell positions designated in IPSA, plans were then optimized with both physical dose and gEUD-based objective functions, using both ASA and GD algorithms. Comparisons were made between plans both qualitatively and based on dose-volume parameters, evaluating each optimization method and objective function. A hybrid objective function was also designed and implemented in the in-house program. The ASA plans are higher on bladder V75% and D2cc (p=0.034) and lower on rectum V75% and D2cc (p=0.034) than the IPSA plans. The ASA and GD plans are not significantly different. The gEUD-based plans have higher homogeneity index (p=0.034), lower overdose index (p=0.005), and lower rectum gEUD and normal tissue complication probability (p=0.005) than the physical dose-based plans. The hybrid function can produce a plan with dosimetric parameters between the physical dose-based and gEUD-based plans. The optimized plans with the same objective value and dose-volume histogram could have different dose distributions. Our optimization program based on ASA and GD algorithms is flexible on objective functions, optimization parameters, and can generate optimized plans comparable with IPSA. Copyright © 2014 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  6. 360-degree 3D transvaginal ultrasound system for high-dose-rate interstitial gynaecological brachytherapy needle guidance

    Science.gov (United States)

    Rodgers, Jessica R.; Surry, Kathleen; D'Souza, David; Leung, Eric; Fenster, Aaron

    2017-03-01

    Treatment for gynaecological cancers often includes brachytherapy; in particular, in high-dose-rate (HDR) interstitial brachytherapy, hollow needles are inserted into the tumour and surrounding area through a template in order to deliver the radiation dose. Currently, there is no standard modality for visualizing needles intra-operatively, despite the need for precise needle placement in order to deliver the optimal dose and avoid nearby organs, including the bladder and rectum. While three-dimensional (3D) transrectal ultrasound (TRUS) imaging has been proposed for 3D intra-operative needle guidance, anterior needles tend to be obscured by shadowing created by the template's vaginal cylinder. We have developed a 360-degree 3D transvaginal ultrasound (TVUS) system that uses a conventional two-dimensional side-fire TRUS probe rotated inside a hollow vaginal cylinder made from a sonolucent plastic (TPX). The system was validated using grid and sphere phantoms in order to test the geometric accuracy of the distance and volumetric measurements in the reconstructed image. To test the potential for visualizing needles, an agar phantom mimicking the geometry of the female pelvis was used. Needles were inserted into the phantom and then imaged using the 3D TVUS system. The needle trajectories and tip positions in the 3D TVUS scan were compared to their expected values and the needle tracks visualized in magnetic resonance images. Based on this initial study, 360-degree 3D TVUS imaging through a sonolucent vaginal cylinder is a feasible technique for intra-operatively visualizing needles during HDR interstitial gynaecological brachytherapy.

  7. High-dose-rate brachytherapy as a monotherapy for prostate cancer--Single-institution results of the extreme fractionation regimen.

    Science.gov (United States)

    Kukiełka, Andrzej Marek; Dąbrowski, Tomasz; Walasek, Tomasz; Olchawa, Agnieszka; Kudzia, Roksana; Dybek, Dorota

    2015-01-01

    We report a single-institution retrospective analysis of the outcomes, disease control, and toxicity of high-dose-rate (HDR) brachytherapy used as the only treatment modality (monotherapy) for localized prostate cancer. Between 2006 and 2012, 77 patients with diagnosed prostate cancer were treated with HDR brachytherapy as a monotherapy. The prescribed dose was 45 Gy in three separate implants 21 days apart, with single fraction per implant. Of the 77 patients, 67 (87%) received hormonal therapy. Prostate-specific antigen failure was defined according to Phoenix consensus, as nadir + 2 ng/mL. Toxicity was scored according to Common Terminology Criteria for Adverse Events, version 4.03. The median followup time was 57 months (4.75 years). The 5-year actuarial overall survival was 98.7%, biochemical control 96.7%, local control 96.9%, and metastasis-free survival 98.4%. Younger age at the beginning of brachytherapy predicted the onset of bounce phenomenon. There were no Grade 3 or higher acute toxicities detected, and Grade 2 genitourinary acute toxicity developed in 19 patients (24.6%). There were no Grade 2 gastrointestinal complications. No Grade 4 or 5 late toxicity was detected. There were also no Grade 3 gastrointestinal toxicities detected. One patient (1.3%) underwent transurethral resection of the prostate because of Grade 3 urethral stenosis and urinary retention. A total of 26 patients (33.8%) developed Grade 2 late toxicity. HDR brachytherapy as monotherapy for localized prostate cancer was feasible, effective, and had acceptable toxicity profile. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  8. The use of adjuvant high-dose-rate breast brachytherapy in patients with collagen vascular disease: a collaborative experience.

    Science.gov (United States)

    Dragun, Anthony E; Harper, Jennifer L; Olyejar, S Eric; Zunzunegui, Raul G; Wazer, David E

    2011-01-01

    To analyze toxicity and cosmesis in patients with collagen vascular disease (CVD) treated with accelerated partial breast irradiation (APBI) via high-dose-rate (HDR) brachytherapy. This is a pooled analysis of patients with early stage and in situ breast cancer with CVD treated with adjuvant multicatheter or balloon brachytherapy. Physicians at multiple institutions were asked to review their experience and report data regarding toxicity and cosmesis in patients with CVD. All patients fit American Society of Breast Surgeons recommendations for APBI and were treated with HDR brachytherapy with ≥ 3 months followup. Nine cases from five institutions are the subject of this analysis. The median patient age was 54 years and median followup was 31 months. All patients had documented history and active signs/symptoms of rheumatoid arthritis, systemic lupus erythematosis, psoriatic arthritis, or scleroderma. All patients had received medical therapy for CVD in the past, and 78% were under active treatment at the time of brachytherapy. All the patients were treated with multicatheter or balloon (MammoSite [Hologic, Inc., Marlboro, MA], MammoSite ML [Hologic, Inc., Marlboro, MA], or Contura [Senorx, Irvine, CA]) brachytherapy with a median volume of 45.5 cc and a median skin distance of 7.5mm. Acute toxicity included Grade 1 skin erythema (5) and catheter-site wound dehiscence (1). Late toxicity included seroma (5), induration (5), pain (2), telangectasia (2), and superficial infection (1). Cosmesis was excellent or good for all the patients. Women with CVD have a toxicity and cosmesis profile consistent with other APBI series. Although confirmatory data is needed, it may not be necessary to exclude these patients from clinical trials of APBI. Copyright © 2011 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  9. Image-guided high-dose-rate brachytherapy of head and neck – a case series study

    Science.gov (United States)

    Kieszko, Dariusz; Brzozowska, Anna; Kordzin’ska-Cisek, Izabela; Mazurkiewicz, Maria

    2016-01-01

    Purpose The aim of the study was the evaluation of image guided transdermal application of interstitial brachytherapy in patients undergoing repeated irradiation for relapsed local tumor of the head and neck area. Material and methods The article describes transdermal application of interstitial high-dose-rate (HDR) brachytherapy in 4 patients treated due to relapsed local tumor in soft palate, submandibular area, laryngopharynx, as well as pterygoid muscles and maxillary sinus. The application was conducted under continuous computed tomography (CT)-image guidance (CT fluoroscopy). Patients qualified for this type of treatment had neoplastic lesions located deep under the skin surface. Because of their location, access to the lesions was limited, and the risk of damaging the adjacent tissues such as vessels and nerves was high. The following parameters have been evaluated: clinical response using RECIST 1.1, incidence of perisurgical complications using CTCAE 4.0 and the frequency of occurrence of radiotherapy related early morbidity using RTOG. Results Various radiation schemes were used, from 3 to 5 fractions of 3.5-5 Gy. The median total dose (D90) was 20.6 Gy. Biologic effective dose (BED) and equivalent 2 Gy (DEQ2) median doses were 30.4 Gy and 25.3 Gy, respectively. In the follow-up period of 3-7 months (the median value of 3.5 months), 2 patients had partial regression of the disease and in 2 others the neoplastic process was stabilized. None of the patients had serious complications of treatment (of 3rd degree or higher). Conclusions Computed tomography-image guided brachytherapy proved to be a safe method of treatment in patients with local relapse in sites, in which traditional visually controlled application was impossible due to risk of complications. Despite short observation period and small study group, it seems justified to conduct prospective studies for the evaluation of efficacy and safety of CT-image guided brachytherapy. PMID:28115962

  10. Image-guided high-dose-rate brachytherapy of head and neck – a case series study

    Directory of Open Access Journals (Sweden)

    Paweł Cisek

    2016-11-01

    Full Text Available Purpose: The aim of the study was the evaluation of image guided transdermal application of interstitial brachytherapy in patients undergoing repeated irradiation for relapsed local tumor of the head and neck area. Material and methods : The article describes transdermal application of interstitial high-dose-rate (HDR bra­chytherapy in 4 patients treated due to relapsed local tumor in soft palate, submandibular area, laryngopharynx, as well as pterygoid muscles and maxillary sinus. The application was conducted under continuous computed tomography (CT-image guidance (CT fluoroscopy. Patients qualified for this type of treatment had neoplastic lesions located deep under the skin surface. Because of their location, access to the lesions was limited, and the risk of damaging the adjacent tissues such as vessels and nerves was high. The following parameters have been evaluated: clinical response using RECIST 1.1, incidence of perisurgical complications using CTCAE 4.0 and the frequency of occurrence of radiotherapy related early morbidity using RTOG. Results: Various radiation schemes were used, from 3 to 5 fractions of 3.5-5 Gy. The median total dose (D90 was 20.6 Gy. Biologic effective dose (BED and equivalent 2 Gy (DEQ2 median doses were 30.4 Gy and 25.3 Gy, respectively. In the follow-up period of 3-7 months (the median value of 3.5 months, 2 patients had partial regression of the disease and in 2 others the neoplastic process was stabilized. None of the patients had serious complications of treatment (of 3rd degree or higher. Conclusions : Computed tomography-image guided brachytherapy proved to be a safe method of treatment in patients with local relapse in sites, in which traditional visually controlled application was impossible due to risk of complications. Despite short observation period and small study group, it seems justified to conduct prospective studies for the evaluation of efficacy and safety of CT-image guided brachytherapy.

  11. The usefulness of fleet rectal enemas on high-dose-rate intracavitary cervical cancer brachytherapy. A prospective trial

    Directory of Open Access Journals (Sweden)

    Ignacio Andres

    2017-05-01

    Full Text Available Purpose: To evaluate the effects of rectal enemas on rectal doses during radical high-dose-rate (HDR intracavitary cervical brachytherapy (BT. Material and methods : Twenty patients suffering from cervical cancer and treated with external beam radiotherapy and HDR-BT were included in a prospective trial. The first brachytherapy fraction was considered the basal status, and patients were instructed to self-administer two rectal cleansing enemas before the second fraction. Dose-volume histogram (DVH values were generated for the rectum and correlated with rectal volume variation. Brachytherapy was carried out with a Fletcher or Utrecht applicator. Results : No significant rectal volume differences were observed between fractions with or without rectal enemas (without, 52.64 ± 15.92 cc; with, 53.16 ± 19.28 cc. There was a significant correlation between both rectal volumes (r = 0.722, p = 0.001. No significant differences were observed in analyzed DVH parameters (median values: ΔD 0.1cc , 4.17 vs. 3.61 Gy; ΔD 1cc , 3.23 vs. 2.87 Gy; Δ D2cc , 2.9 vs. 2.54 Gy; ΔD 5cc , 2.35 vs. 2.05 Gy, for no enema and enema fraction, respectively. No significant rectal volume differences nor DVH parameter differences were observed according the applicator type. Conclusions : Our rectal enemas protocol prior to HDR-BT was ineffective in significantly modifying rectal DVH parameters. No differences were observed according to the type of applicator used.

  12. Preoperative radiotherapy for advanced lower rectal cancer. Combination of external and high-dose-rate intraluminal irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Horikawa, Noriko; Yoshimura, Hitoshi; Tamamoto, Tetsuro; Tsuji, Yoshihiko; Uto, Fumiaki; Ohishi, Hajime; Uchida, Hideo; Fujii, Hisao; Nakano, Hiroshige [Nara Medical Univ., Kashihara (Japan)

    1999-01-01

    This paper reports the therapeutic results of preoperative irradiation using a combination of external irradiation and high dose rate intraluminal irradiation using {sup 60}Co aimed at enhancing postoperative local control of advanced rectal cancer. The subjects comprised 38 patients (RT group) in whom {>=} A{sub 1}` lower rectal cancer was suspected and who underwent preoperative irradiation at this hospital. A control group (N-RT group) consisted of 16 patients subjected to operation alone in whom clinical {>=} A{sub 1}` and postoperative histological study revealed {>=} a{sub 1}. Intraluminal irradiation was performed using a balloon applicator. The external irradiation was performed with a 10 MVX delivering 30-40 Gy/15-20 Fr to the entire pelvic cavity. Using the criteria of Ohboshi and Shimozato to judge the histopathological effect, no cases showed Grade I, while of Grade II, 15 cases showed IIA and 19 cases IIB, Grade III in 4 cases. Grade IIB or above was noted in 23 of 38 (61%). Five and 8-year survival rates were 82.5 and 82.5% in the RT group, and were 79.5 and 79.5% in the N-RT group. Although these differences were not significant, a trend to better survival was found in the RT group. The local recurrence rate was 8% (3/38 cases) in the RT group in contrast to 25% (4/16 cases) in the N-RT group. The following complications developed during radiation therapy: diarrhea 19 (50%), anal pain 18 (47%), and others. Postoperative complications consisted of perineal fluid collection 4 (10%), bowel obstruction 3 cases (8%), an anastomotic insufficiency 3 (8%), fistula formation of bladder 2 (5%), ureteral narrowing 1 (3%), and thrombosis of vein 1 cases (3%) of the RT group, while perineal fluid collection 1 (6%), bowel obstruction 1 (6%), an anastomotic insufficiency 4 (25%) of the N-RT group, only one case of RT group (3%) required surgical treatment for the fistula formation of bladder. (K.H.)

  13. 20-Year Experience With Intraoperative High-Dose-Rate Brachytherapy for Pediatric Sarcoma: Outcomes, Toxicity, and Practice Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Folkert, Michael R.; Tong, William Y. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); LaQuaglia, Michael P. [Department of Pediatric Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Wexler, Leonard H.; Chou, Alexander J.; Magnan, Heather [Department of Pediatrics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Zelefsky, Michael J. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Wolden, Suzanne L., E-mail: woldens@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

    2014-10-01

    Purpose: To assess outcomes and toxicity of high-dose-rate intraoperative radiation therapy (HDR-IORT) in the management of pediatric sarcoma. Methods and Materials: Seventy-five pediatric patients underwent HDR-IORT for sarcoma from May 1993 to November 2013. The median age was 9 years old (36 patients were ≤6 years old). HDR-IORT was part of initial therapy in 37 patients (49%) and for recurrent disease in 38 patients (51%). Forty-one patients (55%) received HDR-IORT and postoperative external beam RT (PORT), and 22 patients (29%) were previously treated with external beam radiation therapy to the IORT site. Local control (LC), overall survival (OS) and event-free survival (EFS) were estimated using Kaplan-Meier methods. Results: At a median follow-up of 7.8 years for surviving patients, 5-year projected rates of LC, EFS, and OS were 63% (95% confidence interval [CI] 50%-76%), 33% (95% CI 21%-45%), and 43% (95% CI 30%-55%), with a median survival of 3.1 years. The 5-year LC, EFS, and OS rates for patients with recurrent disease were 46% (95% CI, 28%-64%), 30% (95% CI, 13%-46%), and 36% (95% CI, 18%-54%). Acute toxicity ≥grade 3 occurred in 2 (2.5%) treatments; late toxicity ≥grade 3 occurred in 4 (5.3%) patients 0.3-9.9 years after HDR-IORT. The incidence of toxicity ≥grade 3 was not associated with HDR-IORT applicator size, HDR-IORT dose, prior RT or PORT, or prior or postoperative chemotherapy, but all toxicity ≥grade 3 occurred in patients ≤6 years treated with HDR-IORT doses ≥12 Gy. Conclusions: HDR-IORT is a well-tolerated component of multimodality therapy for pediatric sarcoma, allowing additional local treatment while reducing external beam exposure. Taking clinical considerations into account, doses between 8-12 Gy are appropriate for HDR-IORT in patients ≤6 years of age.

  14. High-Dose-Rate Brachytherapy as a Monotherapy for Favorable-Risk Prostate Cancer: A Phase II Trial

    Energy Technology Data Exchange (ETDEWEB)

    Barkati, Maroie [Division of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne (Australia); Williams, Scott G., E-mail: scott.williams@petermac.org [Division of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne (Australia); Department of Pathology, University of Melbourne, Melbourne (Australia); Foroudi, Farshad; Tai, Keen Hun; Chander, Sarat [Division of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne (Australia); Department of Pathology, University of Melbourne, Melbourne (Australia); Dyk, Sylvia van [Division of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne (Australia); See, Andrew [Ballarat Austin Radiation Oncology Centre, Ballarat (Australia); Duchesne, Gillian M. [Division of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne (Australia); Department of Pathology, University of Melbourne, Melbourne (Australia)

    2012-04-01

    Purpose: There are multiple treatment options for favorable-risk prostate cancer. High-dose-rate (HDR) brachytherapy as a monotherapy is appealing, but its use is still investigational. A Phase II trial was undertaken to explore the value of such treatment in low-to-intermediate risk prostate cancer. Methods and Materials: This was a single-institution, prospective study. Eligible patients had low-risk prostate cancer features but also Gleason scores of 7 (51% of patients) and stage T2b to T2c cancer. Treatment with HDR brachytherapy with a single implant was administered over 2 days. One of four fractionation schedules was used in a dose escalation study design: 3 fractions of 10, 10.5, 11, or 11.5 Gy. Patients were assessed with the Common Terminology Criteria for Adverse Events version 2.0 for urinary toxicity, the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer scoring schema for rectal toxicity, and the Expanded Prostate Cancer Index Composite (EPIC) questionnaire to measure patient-reported health-related quality of life. Biochemical failure was defined as a prostate-specific antigen (PSA) nadir plus 2 ng/ml. Results: Between 2003 and 2008, 79 patients were enrolled. With a median follow-up of 39.5 months, biochemical relapse occurred in 7 patients. Three- and 5-year actuarial biochemical control rates were 88.4% (95% confidence interval [CI], 78.0-96.2%) and 85.1% (95% CI, 72.5-94.5%), respectively. Acute grade 3 urinary toxicity was seen in only 1 patient. There was no instance of acute grade 3 rectal toxicity. Rates of late grade 3 rectal toxicity, dysuria, hematuria, urinary retention, and urinary incontinence were 0%, 10.3%, 1.3%, 9.0%, and 0%, respectively. No grade 4 or greater toxicity was recorded. Among the four (urinary, bowel, sexual, and hormonal) domains assessed with the EPIC questionnaire, only the sexual domain did not recover with time. Conclusions: HDR brachytherapy as a monotherapy for favorable

  15. High dose rate brachytherapy using custom made superficial mould applicators and Leipzig applicators for non melanoma localized skin cancer

    Energy Technology Data Exchange (ETDEWEB)

    Pellizzon, A. Cassio A.; Miziara, Daniela; Lima, Flavia Pedroso de; Miziara, Miguel

    2014-07-01

    Purpose: advances in technology and the commercial production of Leipzig applicators allowed High Dose Rate after-load brachytherapy (HDR-BT) to address a number of the challenges associated with the delivery of superficial radiation to treat localized non melanoma skin cancer (NMSK). We reviewed our uni-institutional experience on the treatment of NMSK with HDR-BT. Methods: data were collected retrospectively from patients attending the Radiation Oncology Department at AV Carvalho Insitute, Sao Paulo, Brazil. HDR-BT was done using the stepping source HDR 192Ir Microselectron (Nucletron BV). The planning target volume consisted of the macroscopic lesion plus a 5mm to 10mm margin.The depth of treatment was 0.5 cm in smaller (< 2.0 cm) tumors and 10 to 15 mm for lesions bigger than that. Results: Thirteen patients were treated with HDR-BT from June, 2007 to June 2013. The median age and follow up time were 72 (38-90) years old and 36 (range, 7-73) months, respectively. There a predominance of males (61.5%) and of patients referred for adjuvant treatment due positive surgical margins or because they have had only a excision biopsy without safety margins (61.5%). Six (46.2%) patients presented with squamous cell carcinoma and 7 (53.8%) patients presented with basal cell carcinoma. The median tumor size was 20 (range, 5-42) mm. Patients were treated with a median total dose of 40 Gy (range, 20 -60), given in 10 (range, 2-15) fractions, given daily or twice a week. All patients responded very well to treatment and only one patient has failed locally so far, after 38 months of the end of the irradiation. The crude and actuarial 3-year local control rates were 100% and 80%, respectively. Moist desquamation, grade 2 RTOG, was observed in 4 (30.8%) patients. Severe late complication, radiation-induced dyspigmentation, occurred in 2 patients and 1 of the patients also showed telangiectasia in the irradiated area. The cosmetic result was considered good in 84% (11/13) patients

  16. Clinical and cosmetic outcomes in patients treated with high-dose-rate electronic brachytherapy for nonmelanoma skin cancer.

    Science.gov (United States)

    Paravati, Anthony J; Hawkins, Peter G; Martin, Amanda N; Mansy, Gina; Rahn, Doug A; Advani, Sunil J; Hoisak, Jeremy; Dragojevic, Irena; Martin, Peter J; Miller, Charles J; Sanghvi, Parag

    2015-01-01

    To retrospectively analyze clinical and cosmetic outcomes in patients treated for nonmelanoma skin cancer (NMSC) with high-dose-rate (HDR) electronic brachytherapy (EBT) using surface applicators. We identified 127 patients who had 154 NMSC lesions, 149 of which were basal cell carcinoma, treated with HDR EBT at our institution between July 2012 and March 2014. Lesions were treated to 40 Gy in 8 fractions. Local control, acute toxicity, late toxicity, and cosmetic outcomes were analyzed retrospectively. Acute and late toxicities were graded using the Common Terminology Criteria for Adverse Events, version 4.0. Cosmetic outcomes were graded using a standard scale based on the Radiation Therapy Oncology Group and European Organization for Research and Treatment of Cancer Late Radiation Morbidity Scoring Schema. Median (range) follow-up from completion of treatment was 16.1 (3.4-34.8 months). The overall crude recurrence rate was 1.3% (n = 2). Grade 0 to 1 acute radiation dermatitis was observed in 52.6% of treated lesions (n = 81), grade 2 in 34.4% (n = 53), and grade 3 in 13.0% (n = 20). No acute toxicity greater than grade 3 was observed and all acute toxic events resolved after treatment. Grade 0 to 1 late toxicity was observed in 94.2% of cases (n = 145), and grade 2 in 5.8% (n = 9). No late toxicity greater than grade 2 was observed. Across the 152 controlled lesions, cosmetic results were excellent in 94.2% of treated lesions (n = 145), good in 3.3% (n = 5), fair in 0.7% (n = 1), and poor in 0.7% (n = 1). HDR EBT confers promising local control, minimal toxicity, and excellent cosmesis in our institutional experience. It should be considered ideal for NMSC of the head and neck, particularly for basal cell carcinoma involving central facial locations where surgical cosmesis may be inferior. Copyright © 2015 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

  17. Outcomes Associated With 3 Treatment Schedules of High-Dose-Rate Brachytherapy Monotherapy for Favorable-Risk Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Jawad, Maha Saada; Dilworth, Joshua T.; Gustafson, Gary S.; Ye, Hong; Wallace, Michelle [Department of Radiation Oncology, Oakland University William Beaumont School of Medicine, Royal Oak, Michigan (United States); Martinez, Alvaro [Michigan HealthCare Professionals/21" s" t Century Oncology, Farmington Hills, Michigan (United States); Chen, Peter Y. [Department of Radiation Oncology, Oakland University William Beaumont School of Medicine, Royal Oak, Michigan (United States); Krauss, Daniel J., E-mail: DKrauss@beaumont.edu [Department of Radiation Oncology, Oakland University William Beaumont School of Medicine, Royal Oak, Michigan (United States)

    2016-03-15

    Purpose: We report the outcomes associated with 3 high-dose-rate (HDR) brachytherapy regimens used as monotherapy for favorable-risk prostate cancer. Methods and Materials: Four hundred ninety-four patients with stage ≤T2b prostate cancer, Gleason score ≤7, and prostate-specific antigen levels ≤15 ng/mL underwent HDR brachytherapy as monotherapy. Of those, 319 received 38 Gy in 4 fractions, 79 received 24 Gy in 2 fractions, and 96 received 27 Gy in 2 fractions. Acute and chronic genitourinary (GU) and gastrointestinal (GI) toxicities were defined as side effects occurring ≤6 and >6 months, respectively, after radiation therapy (RT) and were graded according to the Common Terminology Criteria for Adverse Events version 3.0. The time to toxicity was calculated from the date of RT completion. Variables were analyzed with χ{sup 2} test. P values <.05 were considered significant. Results: The median overall follow-up time was 4 years (range, 5.5, 3.5, and 2.5 years for 38 Gy, 24 Gy, and 27 Gy, respectively, P<.001). Acute and chronic grade ≥2 GU and GI toxicity profiles were similar among groups. Acceptable rates of grade 2 GU toxicities were seen with overall acute/chronic frequency/urgency, dysuria, retention, incontinence, and hematuria rates of 14%/20%, 6%/7%, 7%/4%, 1.5%/2%, and 1.5%/7%, respectively. Minimal grade 3 and no grade 4 or 5 toxicities were seen. Grade 1, 2, and 3 chronic urethral stricture rates were 0.3%, 2%, and 1%, respectively. All GI toxicities were similar between groups, with overall rates of acute/chronic grade 2 diarrhea, rectal pain/tenesmus, rectal bleeding, and proctitis of 1%/1%, <1%/0.5%, 0%/2%, and <1%/1%, respectively. No grade 3, 4, or 5 toxicities were seen. All comparisons were similar for hormone-naïve patients. The median time to maximal GU/GI toxicity was similar between groups, ranging from 1 to 1.6 to 0.9 to 1.2 years, respectively. There were no differences in clinical outcomes between the 3 groups at 5

  18. Development of a phantom to validate high-dose-rate brachytherapy treatment planning systems with heterogeneous algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Moura, Eduardo S., E-mail: emoura@wisc.edu [Department of Medical Physics, University of Wisconsin–Madison, Madison, Wisconsin 53705 and Instituto de Pesquisas Energéticas e Nucleares—IPEN-CNEN/SP, São Paulo 05508-000 (Brazil); Micka, John A.; Hammer, Cliff G.; Culberson, Wesley S.; DeWerd, Larry A. [Department of Medical Physics, University of Wisconsin–Madison, Madison, Wisconsin 53705 (United States); Rostelato, Maria Elisa C. M.; Zeituni, Carlos A. [Instituto de Pesquisas Energéticas e Nucleares—IPEN-CNEN/SP, São Paulo 05508-000 (Brazil)

    2015-04-15

    Purpose: This work presents the development of a phantom to verify the treatment planning system (TPS) algorithms used for high-dose-rate (HDR) brachytherapy. It is designed to measure the relative dose in a heterogeneous media. The experimental details used, simulation methods, and comparisons with a commercial TPS are also provided. Methods: To simulate heterogeneous conditions, four materials were used: Virtual Water™ (VM), BR50/50™, cork, and aluminum. The materials were arranged in 11 heterogeneity configurations. Three dosimeters were used to measure the relative response from a HDR {sup 192}Ir source: TLD-100™, Gafchromic{sup ®} EBT3 film, and an Exradin™ A1SL ionization chamber. To compare the results from the experimental measurements, the various configurations were modeled in the PENELOPE/penEasy Monte Carlo code. Images of each setup geometry were acquired from a CT scanner and imported into BrachyVision™ TPS software, which includes a grid-based Boltzmann solver Acuros™. The results of the measurements performed in the heterogeneous setups were normalized to the dose values measured in the homogeneous Virtual Water™ setup and the respective differences due to the heterogeneities were considered. Additionally, dose values calculated based on the American Association of Physicists in Medicine-Task Group 43 formalism were compared to dose values calculated with the Acuros™ algorithm in the phantom. Calculated doses were compared at the same points, where measurements have been performed. Results: Differences in the relative response as high as 11.5% were found from the homogeneous setup when the heterogeneous materials were inserted into the experimental phantom. The aluminum and cork materials produced larger differences than the plastic materials, with the BR50/50™ material producing results similar to the Virtual Water™ results. Our experimental methods agree with the PENELOPE/penEasy simulations for most setups and dosimeters. The

  19. Commissioning of a 3D image-based treatment planning system for high-dose-rate brachytherapy of cervical cancer.

    Science.gov (United States)

    Kim, Yongbok; Modrick, Joseph M; Pennington, Edward C; Kim, Yusung

    2016-03-08

    The objective of this work is to present commissioning procedures to clinically implement a three-dimensional (3D), image-based, treatment-planning system (TPS) for high-dose-rate (HDR) brachytherapy (BT) for gynecological (GYN) cancer. The physical dimensions of the GYN applicators and their values in the virtual applicator library were varied by 0.4 mm of their nominal values. Reconstruction uncertainties of the titanium tandem and ovoids (T&O) were less than 0.4 mm on CT phantom studies and on average between 0.8-1.0 mm on MRI when compared with X-rays. In-house software, HDRCalculator, was developed to check HDR plan parameters such as independently verifying active tandem or cylinder probe length and ovoid or cylinder size, source calibration and treatment date, and differences between average Point A dose and prescription dose. Dose-volume histograms were validated using another independent TPS. Comprehensive procedures to commission volume optimization algorithms and process in 3D image-based planning were presented. For the difference between line and volume optimizations, the average absolute differences as a percentage were 1.4% for total reference air KERMA (TRAK) and 1.1% for Point A dose. Volume optimization consistency tests between versions resulted in average absolute differences in 0.2% for TRAK and 0.9 s (0.2%) for total treatment time. The data revealed that the optimizer should run for at least 1 min in order to avoid more than 0.6% dwell time changes. For clinical GYN T&O cases, three different volume optimization techniques (graphical optimization, pure inverse planning, and hybrid inverse optimization) were investigated by comparing them against a conventional Point A technique. End-to-end testing was performed using a T&O phantom to ensure no errors or inconsistencies occurred from imaging through to planning and delivery. The proposed commissioning procedures provide a clinically safe implementation technique for 3D image-based TPS for HDR

  20. A novel adaptive needle insertion sequencing for robotic, single needle MR-guided high-dose-rate prostate brachytherapy

    Science.gov (United States)

    Borot de Battisti, M.; de Senneville, B. Denis; Hautvast, G.; Binnekamp, D.; Lagendijk, J. J. W.; Maenhout, M.; Moerland, M. A.

    2017-05-01

    MR-guided high-dose-rate (HDR) brachytherapy has gained increasing interest as a treatment for patients with localized prostate cancer because of the superior value of MRI for tumor and surrounding tissues localization. To enable needle insertion into the prostate with the patient in the MR bore, a single needle MR-compatible robotic system involving needle-by-needle dose delivery has been developed at our institution. Throughout the intervention, dose delivery may be impaired by: (1) sub-optimal needle positioning caused by e.g. needle bending, (2) intra-operative internal organ motion such as prostate rotations or swelling, or intra-procedural rectum or bladder filling. This may result in failure to reach clinical constraints. To assess the first aforementioned challenge, a recent study from our research group demonstrated that the deposited dose may be greatly improved by real-time adaptive planning with feedback on the actual needle positioning. However, the needle insertion sequence is left to the doctor and therefore, this may result in sub-optimal dose delivery. In this manuscript, a new method is proposed to determine and update automatically the needle insertion sequence. This strategy is based on the determination of the most sensitive needle track. The sensitivity of a needle track is defined as its impact on the dose distribution in case of sub-optimal positioning. A stochastic criterion is thus presented to determine each needle track sensitivity based on needle insertion simulations. To assess the proposed sequencing strategy, HDR prostate brachytherapy was simulated on 11 patients with varying number of needle insertions. Sub-optimal needle positioning was simulated at each insertion (modeled by typical random angulation errors). In 91% of the scenarios, the dose distribution improved when the needle was inserted into the most compared to the least sensitive needle track. The computation time for sequencing was less than 6 s per needle track. The

  1. Dosimetric evaluation of multilumen intracavitary balloon applicator rotation in high-dose-rate brachytherapy for breast cancer.

    Science.gov (United States)

    Kim, Yongbok; Trombetta, Mark G

    2014-01-06

    The objective of this work is to evaluate dosimetric impact of multilumen balloon applicator rotation in high-dose-rate (HDR) brachytherapy for breast cancer. Highly asymmetrical dose distribution was generated for patients A and B, depending upon applicator proximity to skin and rib. Both skin and rib spacing was ≤ 0.7 cm for A; only rib spacing was ≤ 0.7 cm for B. Thirty-five rotation scenarios were simulated for each patient by rotating outer lumens every 10° over ± 180° range with respect to central lumen using mathematically calculated rotational matrix. Thirty-five rotated plans were compared with three plans: 1) original multidwell multilumen (MDML) plan, 2) multidwell single-lumen (MDSL) plan, and 3) single-dwell single-lumen (SDSL) plan. For plan comparison, planning target volume for evaluation (PTV_EVAL) coverage (dose to 95% and 90% volume of PTV_EVAL) (D95 and D90), skin and rib maximal dose (Dmax), and normal breast tissue volume receiving 150% (V150) and 200% (V200) of prescribed dose (PD) were evaluated. Dose variation due to device rotation ranged from -5.6% to 0.8% (A) and -6.5% to 0.2% (B) for PTV_EVAL D95; -5.2% to 0.4% (A) and -4.1% to 0.7% (B) for PTV_EVAL D90; -2.0 to 18.4% (A) and -7.8 to 17.5% (B) for skin Dmax; -11.1 to 22.8% (A) and -4.7 to 55.1% (B) of PD for rib Dmax, respectively. Normal breast tissue V150 and V200 variation was < 1.0 cc, except for -0.1 to 2.5cc (B) of V200. Furthermore, 30° device rotation increased rib Dmax over 145% of PD: 152.9% (A) by clockwise 30° rotation and 152.5% (B) by counterclockwise 30° rotation. For a highly asymmetric dose distribution, device rotation can outweigh the potential benefit of improved dose shaping capability afforded by multilumen and make dosimetric data worse than single-lumen plans unless it is properly corrected.

  2. Image guided radiation therapy boost in combination with high-dose-rate intracavitary brachytherapy for the treatment of cervical cancer

    Directory of Open Access Journals (Sweden)

    Xianliang Wang

    2016-04-01

    Full Text Available Purpose : The purpose of this study was to demonstrate the dosimetric and clinical feasibility of image guided radiation therapy (IGRT combined with high-dose-rate (HDR intracavitary brachytherapy (ICBT to improve dose distribution in cervical cancer treatment. Material and methods: For 42 cervical cancer patients, magnetic resonance imaging (MRI scans were acquired after completion of whole pelvic irradiation 45-46 Gy and 5 fractions of B + I (ICBT + IGRT treatment were subsequently received. The high risk clinical target volume (HRCTV, intermediate risk clinical target volume (IRCTV, bladder, rectum, and sigmoid were contoured on the computed tomography (CT scans. The total planning aim doses for HRCTV was D 90% > 85 Gy, whilst constraints for rectum and sigmoid were D 2cc < 75 Gy and D 2cc < 90 Gy for bladder in terms of an equivalent dose in 2 Gy (EQD2 for external beam radiotherapy (EBRT and brachytherapy boost. The IGRT plan was optimized on top of the ICBT dose distribution. A dosimetric comparison was made between B + I and optimized ICBT (O-ICBT only. Results: The mean D 90% of HRCTV was comparable for B + I and O-ICBT (p = 0.82. For B + I plan, HRCTV D100%, IRCTV D 100% , and IRCTV D 90% were significantly increased by a mean of 10.52 Gy, 5.61 Gy, and 2.70 Gy, respectively (p < 0.01. The D 2cc for bladder, rectum, and sigmoid were lower by a mean of 21.36, 6.78, and 10.65 Gy, respectively (p < 0.01. The mean rectum V60 Gy value over 42 patients was almost the same for both techniques but for bladder and sigmoid B + I had higher V60 Gy mean values as compared with the O-ICBT. Conclusions : B + I can improve dose distribution in cervical cancer treatment; it could be useful for tumors extended beyond the reach of intracavitary/interstitial brachytherapy (IC/ISBT or for centers that are inexperienced or ill-equipped with IC/ISBT techniques. Additional confirmatory prospective studies with larger numbers of patients and longer follow

  3. Salvage high-dose-rate brachytherapy for histologically confirmed macroscopic local relapsed prostate cancer after radical prostatectomy

    Directory of Open Access Journals (Sweden)

    David Buchser

    2016-12-01

    Full Text Available Purpose: To evaluate the feasibility of the use of real-time magnetic resonance imaging (MRI-transrectal ultrasound (TRUS fusion guided high-dose-rate brachytherapy (HDR-BT +/– external beam radiation therapy (EBRT in patients with histologically-proven local relapse after radical prostatectomy. Material and methods : We retrospectively reviewed 13 patients treated with real-time MRI-TRUS fusion HDR-BT for a local relapse of prostate cancer after radical surgery. All patients underwent multiparametric magnetic resonance imaging (mpMRI to confirm the presence of macroscopic lesions in prostate bed, and choline positron emission tomography/computed tomography (PET/CT to rule out nodal or distant metastases. Local failure was confirmed by transrectal biopsy. Patients without previous EBRT received 1 fraction of 15 Gy with HDR-BT plus hypofractionated EBRT (37.5 Gy in 15 fractions. Two patients received 2 fractions of 12 Gy with HDR-BT without EBRT. Follow-up visits were at 1, 3, 6 months, and every 6 months thereafter. Results : After a median follow-up of 7 months, all patients showed an appropriate biochemical response. Median prostate-specific antigen (PSA levels before treatment, 1 month, and 6 months after HDR-BT were 2.62 ng/ml (range: 1.55-9.61, 0.97 ng/ml (range: 0.12-3.14, 0.23 ng/ml (range: 0.1-0.74, respectively. Five patients (42% experienced acute grade 1 GU toxicity and 1 patient (8% suffered from grade 2 GU toxicity. Regarding gastrointestinal (GI toxicity, 5 patients referred grade 1 acute toxicity and 1 grade 2 (proctitis. No late toxicity has been observed so far. Conclusions : MRI-TRUS fusion guided salvage HDR-BT +/– EBRT is a feasible procedure for patients with local macroscopic relapse in tumor bed after radical prostatectomy. Exquisite selection of patients through mpMRI and choline PET/CT is crucial to avoid overtreatment. A larger number of patients and longer follow-up are required in order to draw more solid

  4. High-dose-rate brachytherapy and external-beam radiotherapy for hormone-naïve low- and intermediate-risk prostate cancer: A 7-year experience

    NARCIS (Netherlands)

    S. Aluwini (Shafak); P.H. van Rooij (Peter); W.J. Kirkels (Wim); P.P. Jansen (Peter); J. Praag (John); C.H. Bangma (Chris); I.-K.K. Kolkman-Deurloo (Inger-Karina)

    2012-01-01

    textabstractPurpose: To report clinical outcomes and early and late complications in 264 hormone-naïve patients with low- and intermediate-risk prostate cancer treated with high-dose-rate brachytherapy (HDR-BT) in combination with external-beam radiotherapy (EBRT). Methods and Materials: Between

  5. Effect of rectal enemas on rectal dosimetric parameters during high-dose-rate vaginal cuff brachytherapy. A prospective trial

    Energy Technology Data Exchange (ETDEWEB)

    Sabater, Sebastia; Andres, Ignacio; Sevillano, Marimar; Berenguer, Roberto; Aguayo, Manuel; Villas, Maria Victoria [Complejo Hospitalario Universitario de Albacete (CHUA), Department of Radiation Oncology, Albacete (Spain); Gascon, Marina; Arenas, Meritxell [Hospital Universitari Sant Joan, Department of Radiation Oncology, Reus (Spain); Rovirosa, Angeles; Camacho-Lopez, Cristina [University of Barcelona, IDIBAPS, Gynecological Cancer Unit, Radiation Oncology Department, ICMHO, Hospital Clinic, Barcelona (Spain)

    2016-04-15

    To evaluate the effects of rectal enemas on rectal doses during postoperative high-dose-rate (HDR) vaginal cuff brachytherapy (VCB). This prospective trial included 59 patients. Two rectal cleansing enemas were self-administered before the second fraction, and fraction 1 was considered the basal status. Dose-volume histogram (DVH) values were generated for the rectum and correlated with rectal volume variation. Statistical analyses used paired and unpaired t-tests. Despite a significant 15 % reduction in mean rectal volume (44.07 vs. 52.15 cc, p = 0.0018), 35.6 % of patients had larger rectums after rectal enemas. No significant rectal enema-related DVH differences were observed compared to the basal data. Although not statistically significant, rectal cleansing-associated increases in mean rectal DVH values were observed: D{sub 0.1} {sub cc}: 6.6 vs. 7.21 Gy; D{sub 1} {sub cc}: 5.35 vs. 5.52 Gy; D{sub 2} {sub cc}: 4.67 vs. 4.72 Gy, before and after rectal cleaning, respectively (where D{sub x} {sub cc} is the dose to the most exposed x cm {sup 3}). No differences were observed in DVH parameters according to rectal volume increase or decrease after the enema. Patients whose rectal volume increased also had significantly larger DVH parameters, except for D{sub 5} {sub %}, D{sub 25} {sub %}, and D{sub 50} {sub %}. In contrast, in patients whose rectal volume decreased, significance was only seen for D{sub 25} {sub %} and D{sub 50} {sub %} (D{sub x} {sub %} dose covering x % of the volume). In the latter patients, nonsignificant reductions in D{sub 2} {sub cc}, D{sub 5} {sub cc} and V{sub 5} {sub Gy} (volume receiving at least 5 Gy) were observed. The current rectal enemas protocol was ineffective in significantly modifying rectal DVH parameters for HDR-VCB. (orig.) [German] Beurteilung der Auswirkungen von rektalen Dosen waehrend postoperativer High-Dose-Rate-(HDR-)Brachytherapie an der Scheidenmanschette (''vaginal cuff brachytherapy'', VCB). An

  6. Implementation of a High-Dose-Rate Brachytherapy Program for Carcinoma of the Cervix in Senegal: A Pragmatic Model for the Developing World

    Energy Technology Data Exchange (ETDEWEB)

    Einck, John P., E-mail: jeinck@ucsd.edu [Department of Radiation Medicine and Applied Sciences, University of California San Diego, San Diego, California (United States); Hudson, Alana [Department of Oncology, Tom Baker Cancer Centre, University of Calgary, Calgary, Alberta (Canada); Shulman, Adam C. [Overlook Medical Center, Summit, New Jersey (United States); Yashar, Catheryn M. [Department of Radiation Medicine and Applied Sciences, University of California San Diego, San Diego, California (United States); Dieng, Mamadou M.; Diagne, Magatte; Gueye, Latifatou; Gningue, Fama; Gaye, Pape M. [Départemént de Radiothérapie, Institut Joliot-Curie, Hôpital Aristide Le Dantec, Dakar (Senegal); Fisher, Brandon J. [GammaWest Cancer Services, Salt Lake City, Utah (United States); Mundt, Arno J. [Department of Radiation Medicine and Applied Sciences, University of California San Diego, San Diego, California (United States); Brown, Derek W. [Department of Oncology, Tom Baker Cancer Centre, University of Calgary, Calgary, Alberta (Canada)

    2014-07-01

    West Africa has one of the highest incidence rates of carcinoma of the cervix in the world. The vast majority of women do not have access to screening or disease treatment, leading to presentation at advanced stages and to high mortality rates. Compounding this problem is the lack of radiation treatment facilities in Senegal and many other parts of the African continent. Senegal, a country of 13 million people, had a single {sup 60}Co teletherapy unit before our involvement and no brachytherapy capabilities. Radiating Hope, a nonprofit organization whose mission is to provide radiation therapy equipment to countries in the developing world, provided a high-dose-rate afterloading unit to the cancer center for curative cervical cancer treatment. Here we describe the implementation of high-dose-rate brachytherapy in Senegal requiring a nonstandard fractionation schedule and a novel treatment planning approach as a possible blueprint to providing this technology to other developing countries.

  7. Comparison of (192) Ir, (169) Yb, and (60) Co high-dose rate brachytherapy sources for skin cancer treatment.

    Science.gov (United States)

    Safigholi, Habib; Meigooni, Ali S; Song, William Y

    2017-09-01

    To evaluate the possibility of utilizing the high-dose rate (HDR) (169) Yb and (60) Co sources, in addition to (192) Ir, for the treatment of skin malignancies with conical applicators. Monte Carlo (MC) simulations were used to benchmark the dosimetric parameters of single (169) Yb (4140), (60) Co (Co0.A86), and (192) Ir (mHDR-V2) brachytherapy sources in a water phantom and compared their results against published data. A standard conical tungsten alloy Leipzig-style applicator (Stand.Appl) was used for determination of the dose distributions at various depths with a single dwell position of the HDR sources. The HDR sources were modeled with its long axis parallel to the treatment plane within the opening section of the applicator. The source-to-surface distance (SSD) was 1.6 cm, which included a 0.1 cm thick removable plastic end-cap used for clinical applications. The prescription depth was considered to be 0.3 cm in a water phantom following the definitions in the literature for this treatment technique. Dose distributions generated with the Stand.Appl and the (169) Yb and (60) Co sources have been compared with those of the (192) Ir source, for the same geometry. Then, applicator wall thickness for the (60) Co source was increased (doubled) in MC simulations in order to minimize the leakage dose and penumbra to levels that were comparable to that from the (192) Ir source. For each source-applicator combination, the optimized plastic end-cap dimensions were determined in order to avoid over-dosage to the skin surface. The normalized dose profiles at the prescription depth for the (169) Yb-Stand.Appl and the (60) Co-double-wall applicator were found to be similar to that of the (192) Ir-Stand.Appl, with differences percentage depth doses (PDD) for the (192) Ir-, (169) Yb- and (60) Co-Stand.Appl were found to be comparable to the values with the (60) Co-double-walled applicator, with differences depth were also comparable at 0.309, 0.316, and 0.298 (cGy/hU) for

  8. The American College of Radiology and the American Brachytherapy Society practice parameter for the performance of radionuclide-based high-dose-rate brachytherapy.

    Science.gov (United States)

    Erickson, Beth A; Bittner, Nathan H J; Chadha, Manjeet; Mourtada, Firas; Demanes, D Jeffrey

    Brachytherapy is a radiation therapy method in which radionuclide sources are used to deliver a radiation dose at a distance of up to a few centimeters by surface, intracavitary, intraluminal, or interstitial application. This practice parameter refers only to the use of radionuclides for brachytherapy. Brachytherapy alone or combined with external beam therapy plays an important role in the management and treatment of patients with cancer. High-dose-rate (HDR) brachytherapy uses radionuclides such as iridium-192 at dose rates of 20 cGy per minute (12 Gy per hour) or more to a designated target point or volume. High-dose-rate (HDR) brachytherapy is indicated for treating malignant or benign tumors where the treatment volume or targeted points are defined and accessible. Copyright © 2016 American Brachytherapy Society and American College of Radiology. Published by Elsevier Inc. All rights reserved.

  9. A Novel Form of Breast Intraoperative Radiation Therapy With CT-Guided High-Dose-Rate Brachytherapy: Results of a Prospective Phase 1 Clinical Trial

    Energy Technology Data Exchange (ETDEWEB)

    Showalter, Shayna L., E-mail: snl2t@virginia.edu [Division of Surgical Oncology, Department of Surgery, University of Virginia School of Medicine, Charlottesville, Virginia (United States); Petroni, Gina [Division of Translation Research and Applied Statistics, Department of Public Health Sciences, University of Virginia School of Medicine, Charlottesville, Virginia (United States); Trifiletti, Daniel M.; Libby, Bruce [Department of Radiation Oncology, University of Virginia School of Medicine, Charlottesville, Virginia (United States); Schroen, Anneke T.; Brenin, David R. [Division of Surgical Oncology, Department of Surgery, University of Virginia School of Medicine, Charlottesville, Virginia (United States); Dalal, Parchayi [Department of Radiation Oncology, University of Virginia School of Medicine, Charlottesville, Virginia (United States); Smolkin, Mark [Division of Translation Research and Applied Statistics, Department of Public Health Sciences, University of Virginia School of Medicine, Charlottesville, Virginia (United States); Reardon, Kelli A.; Showalter, Timothy N. [Department of Radiation Oncology, University of Virginia School of Medicine, Charlottesville, Virginia (United States)

    2016-09-01

    Purpose: Existing intraoperative radiation therapy (IORT) techniques are criticized for the lack of image guided treatment planning and energy deposition with, at times, poor resultant dosimetry and low radiation dose. We pioneered a novel method of IORT that incorporates customized, computed tomography (CT)-based treatment planning and high-dose-rate (HDR) brachytherapy to overcome these drawbacks: CT-HDR-IORT. Methods and Materials: A phase 1 study was conducted to demonstrate the feasibility and safety of CT-HDR-IORT. Eligibility criteria included age ≥50 years, invasive or in situ breast cancer, tumor size <3 cm, and N0 disease. Patients were eligible before or within 30 days of breast-conserving surgery (BCS). BCS was performed, and a multilumen balloon catheter was placed. CT images were obtained, a customized HDR brachytherapy plan was created, and a dose of 12.5 Gy was delivered to 1-cm depth from the balloon surface. The catheter was removed, and the skin was closed. The primary endpoints were feasibility and acute toxicity. Feasibility was defined as IORT treatment interval (time from CT acquisition until IORT completion) ≤90 minutes. The secondary endpoints included dosimetry, cosmetic outcome, quality of life, and late toxicity. Results: Twenty-eight patients were enrolled. The 6-month follow-up assessments were completed by 93% of enrollees. The median IORT treatment interval was 67.2 minutes (range, 50-108 minutes). The treatment met feasibility criteria in 26 women (93%). The dosimetric goals were met in 22 patients (79%). There were no Radiation Therapy Oncology Group grade 3+ toxicities; 6 patients (21%) experienced grade 2 events. Most patients (93%) had good/excellent cosmetic outcomes at the last follow-up visit. Conclusions: CT-HDR-IORT is feasible and safe. This promising approach for a conformal, image-based, higher-dose breast IORT is being evaluated in a phase 2 trial.

  10. Time-driven activity-based costing of low-dose-rate and high-dose-rate brachytherapy for low-risk prostate cancer.

    Science.gov (United States)

    Ilg, Annette M; Laviana, Aaron A; Kamrava, Mitchell; Veruttipong, Darlene; Steinberg, Michael; Park, Sang-June; Burke, Michael A; Niedzwiecki, Douglas; Kupelian, Patrick A; Saigal, Christopher

    Cost estimates through traditional hospital accounting systems are often arbitrary and ambiguous. We used time-driven activity-based costing (TDABC) to determine the true cost of low-dose-rate (LDR) and high-dose-rate (HDR) brachytherapy for prostate cancer and demonstrate opportunities for cost containment at an academic referral center. We implemented TDABC for patients treated with I-125, preplanned LDR and computed tomography based HDR brachytherapy with two implants from initial consultation through 12-month followup. We constructed detailed process maps for provision of both HDR and LDR. Personnel, space, equipment, and material costs of each step were identified and used to derive capacity cost rates, defined as price per minute. Each capacity cost rate was then multiplied by the relevant process time and products were summed to determine total cost of care. The calculated cost to deliver HDR was greater than LDR by $2,668.86 ($9,538 vs. $6,869). The first and second HDR treatment day cost $3,999.67 and $3,955.67, whereas LDR was delivered on one treatment day and cost $3,887.55. The greatest overall cost driver for both LDR and HDR was personnel at 65.6% ($4,506.82) and 67.0% ($6,387.27) of the total cost. After personnel costs, disposable materials contributed the second most for LDR ($1,920.66, 28.0%) and for HDR ($2,295.94, 24.0%). With TDABC, the true costs to deliver LDR and HDR from the health system perspective were derived. Analysis by physicians and hospital administrators regarding the cost of care afforded redesign opportunities including delivering HDR as one implant. Our work underscores the need to assess clinical outcomes to understand the true difference in value between these modalities. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  11. Tolerance of the vaginal vault to high-dose rate brachytherapy and concomitant chemo-pelvic irradiation: Long-term perspective.

    Science.gov (United States)

    Kaidar-Person, Orit; Abdah-Bortnyak, Roxolyana; Amit, Amnon; Nevelsky, Alexander; Berniger, Alison; Bar-Deroma, Raquel; Ben-Yosef, Rahamim; Kuten, Abraham

    2014-01-01

    We sought to determine the tolerance level and complication rates of the vaginal vault to combined high-dose-rate intra-cavitary brachytherapy with concomitant chemo-radiotherapy. A retrospective review of medical records of all the patients who received definitive chemo-radiotherapy for cervical cancer between 1998 and 2002 was undertaken. The records were reviewed for doses and for radiation-associated early and late sequelae of the vagina, rectum and bladder. Cumulative biological effective dose was calculated for two reference vaginal surface points. Fifty patients were included. Average age at diagnosis was 54 years. Median follow-up was 59 months. There were no recorded instances of acute grade IV toxicity. Maximal high-dose-rate vaginal surface dose (upper central point) was 103 Gy, and maximal brachytherapy lateral surface dose was 70 Gy. Maximal cumulative biological effective dose for the lateral surface reference point was 465.5 Gy3, and the maximal cumulative biological effective dose for the superior reference point was 878.6 Gy3. There were no cases of vaginal necrosis or fistulas, and no cases of grade IV late vaginal, rectal or bladder toxicity. No correlation was found between the maximal vaginal surface dose and vaginal, rectal or bladder toxicity. The maximal surface HDR brachytherapy dose of 103 Gy and the maximal cBED of 878.6 Gy3 were not associated with fistula or necrosis or other grade 3-4 vaginal complications. Concomitant chemo-radiotherapy, including pelvic radiotherapy and high-dose-rate intracavitary brachytherapy, is relatively safe for cervical cancer patients.

  12. Comparison of manual and inverse optimisation techniques in high dose rate intracavitary brachytherapy of cervical cancer: A dosimetric study.

    Science.gov (United States)

    Kannan, Ram Abhinav; Gururajachar, Janaki Manur; Ponni, Arul; Koushik, Kirthi; Kumar, Mohan; Alva, Ram Charith; Harjani, Ritika; Murthy, Arvind

    2015-01-01

    To compare dosimetrically the manual optimisation with IPSA using dose volume histograms (DVH) among patients treated for carcinoma of cervix with intracavitary brachytherapy. With the advent of advanced imaging modalities, there has been a shift from conventional X-ray based planning to three-dimensional planning. Manual optimisation is widely used across various institutions but it is time consuming and operator dependant. Inverse planning simulated annealing (IPSA) is now available in various brachytherapy planning systems. But there is a paucity of studies comparing manual optimisation and IPSA in treatment of carcinoma cervix with intracavitary brachytherapy and hence this study. Fifteen consecutive patients treated between December 2013 and March 2014 with intracavitary brachytherapy for carcinoma of cervix were selected for this study. All patients were initially treated with external beam radiotherapy followed by intracavitary brachytherapy. The DVH was evaluated and compared between manually optimised plans and IPSA in the same set of patients. There was a significant improvement in the HRCTV coverage, mean V100 of 87.75% and 82.37% (p = 0.001) and conformity index 0.67 and 0.6 (p = 0.007) for plans generated using IPSA and manual optimisation, respectively. Homogeneity index and dose to the OARs remained similar between the two groups. The use of inverse planning in intracavitary brachytherapy of cervix has shown a significant improvement in the target volume coverage when compared with manual planning.

  13. Treatment of squamous cell carcinomas of the floor of the mouth and tongue by interstitial high-dose-rate irradiation using iridium-192

    Energy Technology Data Exchange (ETDEWEB)

    Klein, M.; Menneking, H.; Langford, A. [Humboldt Univ. of Berlin, Clinic for Maxillofacial Surgery, Berlin (Germany); Koch, K. [Clinic Ernst von Bergman, Clinic for Radiation Therapy, Potsdam (Germany); Stahl, H. [Humboldt Univ. of Berlin, Dept. of Radiation Oncology, Berlin (Germany)

    1998-02-01

    The results are presented of afterloading high-dose-rate-radiation with iridium-192 in 34 patients with squamous cell carcinomas of the floor of the mouth and tongue. Some patients were also treated surgically or given percutaneous radio- or chemotherapy. At the time of diagnosis, 28.0% had a T2 tumour, 41.9% a T3 tumour and 30.1% a T4 tumour. 41.2% had positive lymph nodes and 2.9% distant metastases. The response rate was 64.7%, 26.5% of which were complete remissions and 38.2% partial remissions. In 61.8% of cases, the tumour was recurrent and responded with a rate as high as 57.2%, 23.9% of which were complete remissions and 33.3% partial remissions. Survival times were dependent upon therapy results. The mean survival of patients with complete remission was 40.3 months, with partial remission 16.1 months as opposed to 7.2 and 3.5 months respectively in patients showing no change or progressive disease. It can be concluded that afterloading therapy using high-dose-rate-radiation with iridium-192 achieves good palliative results and should be looked at as a supplementary treatment modality for squamous cell carcinomas of the floor of the mouth and tongue. (au). 12 refs.

  14. Medically inoperable endometrial cancer in patients with a high body mass index (BMI): Patterns of failure after 3-D image-based high dose rate (HDR) brachytherapy

    DEFF Research Database (Denmark)

    Acharya, Sahaja; Esthappan, Jacqueline; Badiyan, Shahed

    2016-01-01

    BACKGROUND AND PURPOSE: High BMI is a reason for medical inoperability in patients with endometrial cancer in the United States. Definitive radiation is an alternative therapy for these patients; however, data on patterns of failure after definitive radiotherapy are lacking. We describe...... the patterns of failure after definitive treatment with 3-D image-based high dose rate (HDR) brachytherapy for medically inoperable endometrial cancer. MATERIALS AND METHODS: Forty-three consecutive patients with endometrial cancer FIGO stages I-III were treated definitively with HDR brachytherapy...

  15. Dosimetric and radiobiological comparison of volumetric modulated arc therapy, high-dose rate brachytherapy, and low-dose rate permanent seeds implant for localized prostate cancer.

    Science.gov (United States)

    Yang, Ruijie; Zhao, Nan; Liao, Anyan; Wang, Hao; Qu, Ang

    2016-01-01

    To investigate the dosimetric and radiobiological differences among volumetric modulated arc therapy (VMAT), high-dose rate (HDR) brachytherapy, and low-dose rate (LDR) permanent seeds implant for localized prostate cancer. A total of 10 patients with localized prostate cancer were selected for this study. VMAT, HDR brachytherapy, and LDR permanent seeds implant plans were created for each patient. For VMAT, planning target volume (PTV) was defined as the clinical target volume plus a margin of 5mm. Rectum, bladder, urethra, and femoral heads were considered as organs at risk. A 78Gy in 39 fractions were prescribed for PTV. For HDR and LDR plans, the dose prescription was D90 of 34Gy in 8.5Gy per fraction, and 145Gy to clinical target volume, respectively. The dose and dose volume parameters were evaluated for target, organs at risk, and normal tissue. Physical dose was converted to dose based on 2-Gy fractions (equivalent dose in 2Gy per fraction, EQD2) for comparison of 3 techniques. HDR and LDR significantly reduced the dose to rectum and bladder compared with VMAT. The Dmean (EQD2) of rectum decreased 22.36Gy in HDR and 17.01Gy in LDR from 30.24Gy in VMAT, respectively. The Dmean (EQD2) of bladder decreased 6.91Gy in HDR and 2.53Gy in LDR from 13.46Gy in VMAT. For the femoral heads and normal tissue, the mean doses were also significantly reduced in both HDR and LDR compared with VMAT. For the urethra, the mean dose (EQD2) was 80.26, 70.23, and 104.91Gy in VMAT, HDR, and LDR brachytherapy, respectively. For localized prostate cancer, both HDR and LDR brachytherapy were clearly superior in the sparing of rectum, bladder, femoral heads, and normal tissue compared with VMAT. HDR provided the advantage in sparing of urethra compared with VMAT and LDR. Copyright © 2016 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

  16. High-dose rate iridium-192 brachytherapy with flexible applicator. A trial toward decrease of stress during treatment and improvement of quality of life

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Keiji; Kasahara, Kotaro; Karashima, Takashi; Inoue, Yuichiro; Kariya, Shinji; Inomata, Taisuke; Yoshida, Shoji; Shuin, Taro [Kochi Medical School, Nankoku (Japan)

    2001-07-01

    We tried to improve the materials and methods of high-dose rate Iridium-192 brachytherapy for localized prostate cancer and evaluated the stress during the treatment in 20 patients with whom the therapy was performed. Rigid applicators made of stainless steel of 1.6 mm in diameter were indwelt with a template as usual for 30 hours in 14 patients (group A). Flexible applicators made of polyoxymethylene rosin (POM) of 2.0 mm in diameter were indwelt without a template for 30 hours after the applicator insertion in 6 patients (group B). We made inquiries about lumbago, inconvenience and necessity of assistant help and sleep in the course of therapy, and urinary incontinence and erectile function after the course of therapy as the QOL. The stress during the course of therapy in the patients of group B was obviously less than that of group A. There were no significant differences in urinary incontinence and erectile function after the course of therapy between group A and B. In this study, our trial successfully reduced the stress during the course of therapy in the patients with localized prostate cancer in the course of high-dose rate Iridium-192 brachytherapy. (author)

  17. Role of vaginal pallor reaction in predicting late vaginal stenosis after high-dose-rate brachytherapy in treatment-naive patients with cervical cancer.

    Science.gov (United States)

    Yoshida, Ken; Yamazaki, Hideya; Nakamura, Satoaki; Masui, Koji; Kotsuma, Tadayuki; Akiyama, Hironori; Tanaka, Eiichi; Yoshikawa, Nobuhiko; Uesugi, Yasuo; Shimbo, Taiju; Narumi, Yoshifumi; Yoshioka, Yasuo

    2015-07-01

    To assess actual rates of late vaginal stenosis and identify predisposing factors for complications among patients with previously untreated cervical cancer following high-dose-rate brachytherapy. We performed longitudinal analyses of 57 patients using the modified Dische score at 6, 12, 18, 24, 36, and 60 months after treatment, which consisted of 15 interstitial brachytherapys and 42 conventional intracavitary brachytherapys, with a median follow-up time of 36 months (range, 6 to 144 months). More than half of the patients developed grade 1 (mild) vaginal stenosis within the first year of follow-up, and grade 2 (97.5%, moderate) to grade 3 (severe) stenosis gradually increased with time. Actual stenosis rates for grade 1, 2, and 3 were 97.5% (95% confidence interval [CI], 92.7 to 97.5), 60.7% (95% CI, 42.2 to 79.3), and 7.4% (95% CI, 0 to 18.4) at 3 years after treatment. Pallor reaction grade 2-3 at 6 months was only a statistically significant predisposing factor for grade 2-3 late vaginal stenosis 3 years or later with a hazard ratio of 3.48 (95% CI, 1.32 to 9.19; p=0.018) by a multivariate Cox proportional hazard model. Patients with grade 0-1 pallor reaction at 6 months showed a grade ≥2 vaginal stenosis rate of 53%, whereas the grade 2-3 pallor reaction group achieved a grade ≥2 vaginal stenosis rate at 3 years at 100% (p=0.001). High-dose-rate brachytherapy was associated with high incidence of late vaginal stenosis. Pallor reaction grade 2-3 at 6 months was predictive of late grade 2-3 vaginal stenosis at 3 years after treatment. These findings should prove helpful for patient counseling and preventive intervention.

  18. Cancer radiotherapy based on femtosecond IR laser-beam filamentation yielding ultra-high dose rates and zero entrance dose.

    Science.gov (United States)

    Meesat, Ridthee; Belmouaddine, Hakim; Allard, Jean-François; Tanguay-Renaud, Catherine; Lemay, Rosalie; Brastaviceanu, Tiberius; Tremblay, Luc; Paquette, Benoit; Wagner, J Richard; Jay-Gerin, Jean-Paul; Lepage, Martin; Huels, Michael A; Houde, Daniel

    2012-09-18

    Since the invention of cancer radiotherapy, its primary goal has been to maximize lethal radiation doses to the tumor volume while keeping the dose to surrounding healthy tissues at zero. Sadly, conventional radiation sources (γ or X rays, electrons) used for decades, including multiple or modulated beams, inevitably deposit the majority of their dose in front or behind the tumor, thus damaging healthy tissue and causing secondary cancers years after treatment. Even the most recent pioneering advances in costly proton or carbon ion therapies can not completely avoid dose buildup in front of the tumor volume. Here we show that this ultimate goal of radiotherapy is yet within our reach: Using intense ultra-short infrared laser pulses we can now deposit a very large energy dose at unprecedented microscopic dose rates (up to 10(11) Gy/s) deep inside an adjustable, well-controlled macroscopic volume, without any dose deposit in front or behind the target volume. Our infrared laser pulses produce high density avalanches of low energy electrons via laser filamentation, a phenomenon that results in a spatial energy density and temporal dose rate that both exceed by orders of magnitude any values previously reported even for the most intense clinical radiotherapy systems. Moreover, we show that (i) the type of final damage and its mechanisms in aqueous media, at the molecular and biomolecular level, is comparable to that of conventional ionizing radiation, and (ii) at the tumor tissue level in an animal cancer model, the laser irradiation method shows clear therapeutic benefits.

  19. Preventing Complications from High-Dose Rate Brachytherapy when Treating Mobile Tongue Cancer via the Application of a Modular Lead-Lined Spacer.

    Directory of Open Access Journals (Sweden)

    Shumei Murakami

    Full Text Available To point out the advantages and drawbacks of high-dose rate brachytherapy in the treatment of mobile tongue cancer and indicate the clinical importance of modular lead-lined spacers when applying this technique to patients.First, all basic steps to construct the modular spacer are shown. Second, we simulate and evaluate the dose rate reduction for a wide range of spacer configurations.With increasing distance to the source absorbed doses dropped considerably. Significantly more shielding was obtained when lead was added to the spacer and this effect was most pronounced on shorter (i.e. more clinically relevant distances to the source.The modular spacer represents an important addition to the planning and treatment stages of mobile tongue cancer using HDR-ISBT.

  20. Analysis of Chromosomal Aberrations after Low and High Dose Rate Gamma Irradiation in ATM or NBS Suppressed Human Fibroblast Cells

    Science.gov (United States)

    Hada, M.; Huff, J. L.; Patel, Z.; Pluth, J. M.; George, K. A.; Cucinotta, F. A.

    2009-01-01

    condensation (PCC) technique at the first mitosis post-irradiation. Chromosomes were analyzed using a multicolor fluorescence in-situ hybridization (mFISH) chromosome painting method. Preliminary analysis showed that chromosomal exchanges were increased in the cells treated with the specific ATM inhibitor. Possible cytogenetic signatures of acute and low dose-rate gamma irradiation in ATM or Nibrin deficient and suppressed cells will be discussed.

  1. TU-AB-201-08: Rotating Shield High Dose Rate Brachytherapy with 153Gd and 75Se Isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Renaud, M; Seuntjens, J; Enger, S [McGill University, Montreal, Quebec (Canada); Flynn, R [University of Iowa Hospitals and Clinics, Iowa City, IA (United States)

    2015-06-15

    Purpose: To introduce rotating shield brachytherapy (RSBT) for different cancer sites with {sup 153}Gd and {sup 75}Se isotopes. RSBT is a form of intensity modulated brachytherapy, using shielded rotating catheters to provide a better dose distribution in the tumour while protecting healthy tissue. Methods: BrachySource, a Geant4-based Monte Carlo dose planning system was developed for investigation of RSBT with {sup 153}Gd and {sup 75}Se for different cancer sites. Dose distributions from {sup 153}Gd, {sup 75}Se and {sup 192}Ir isotopes were calculated in a 40 cm radius water phantom by using the microSelectron-v2 source model. The source was placed inside a cylindrical platinum shield with 1.3 mm diameter. An emission window coinciding with the active core of the source was created by removing half (180°) of the wall of the shield. Relative dose rate distributions of the three isotopes were simulated. As a proof of concept, a breast cancer patient originally treated with Mammosite was re-simulated with unshielded {sup 192}Ir and shielded {sup 153}Gd. Results: The source with the lowest energy, {sup 153}Gd, decreased the dose on the shielded side by 91%, followed by {sup 75}Se and {sup 192}Ir with 36% and 16% reduction at 1 cm from the source. The breast cancer patient simulation showed the ability of shielded {sup 153}Gd to spare the chest wall by a 90% dose reduction when only one emission window angle is considered. In this case, fully covering the PTV would require more delivery angles and the chest wall dose reduction would be less, however, the simulation demonstrates the potential of shielded {sup 153}Gd to selectively isolate organs at risk. Conclusion: Introducing {sup 153}Gd and {sup 75}Se sources combined with RSBT will allow escalation of dose in the target volume while maintaining low doses in radiation sensitive healthy tissue. Tailoring treatments to each individual patient by treating all parts of the tumour without over-irradiation of normal

  2. Sexual Functioning Among Endometrial Cancer Patients Treated With Adjuvant High-Dose-Rate Intra-Vaginal Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Damast, Shari, E-mail: shari.damast@yale.edu [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Alektiar, Kaled M. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Goldfarb, Shari [Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Eaton, Anne; Patil, Sujata [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Mosenkis, Jeffrey [Department of Comparative Human Development, University of Chicago, Chicago, Illinois (United States); Bennett, Antonia [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Atkinson, Thomas [Department of Psychiatry, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Jewell, Elizabeth; Leitao, Mario; Barakat, Richard; Carter, Jeanne [Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Basch, Ethan [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

    2012-10-01

    Purpose: We used the Female Sexual Function Index (FSFI) to investigate the prevalence of sexual dysfunction (SD) and factors associated with diminished sexual functioning in early stage endometrial cancer (EC) patients treated with simple hysterectomy and adjuvant brachytherapy. Methods and Materials: A cohort of 104 patients followed in a radiation oncology clinic completed questionnaires to quantify current levels of sexual functioning. The time interval between hysterectomy and questionnaire completion ranged from <6 months to >5 years. Multivariate regression was performed using the FSFI as a continuous variable (score range, 1.2-35.4). SD was defined as an FSFI score of <26, based on the published validation study. Results: SD was reported by 81% of respondents. The mean ({+-} standard deviation) domain scores in order of highest-to-lowest functioning were: satisfaction, 2.9 ({+-}2.0); orgasm, 2.5 ({+-}2.4); desire, 2.4 ({+-}1.3); arousal, 2.2 ({+-}2.0); dryness, 2.1 ({+-}2.1); and pain, 1.9 ({+-}2.3). Compared to the index population in which the FSFI cut-score was validated (healthy women ages 18-74), all scores were low. Compared to published scores of a postmenopausal population, scores were not statistically different. Multivariate analysis isolated factors associated with lower FSFI scores, including having laparotomy as opposed to minimally invasive surgery (effect size, -7.1 points; 95% CI, -11.2 to -3.1; P<.001), lack of vaginal lubricant use (effect size, -4.4 points; 95% CI, -8.7 to -0.2, P=.040), and short time interval (<6 months) from hysterectomy to questionnaire completion (effect size, -4.6 points; 95% CI, -9.3-0.2; P=.059). Conclusions: The rate of SD, as defined by an FSFI score <26, was prevalent. The postmenopausal status of EC patients alone is a known risk factor for SD. Additional factors associated with poor sexual functioning following treatment for EC included receipt of laparotomy and lack of vaginal lubricant use.

  3. TLD skin dose measurements and acute and late effects after lumpectomy and high-dose-rate brachytherapy only for early breast cancer.

    Science.gov (United States)

    Perera, Francisco; Chisela, Frank; Stitt, Larry; Engel, Jay; Venkatesan, Varagur

    2005-08-01

    This report examines the relationships between measured skin doses and the acute and late skin and soft tissue changes in a pilot study of lumpectomy and high-dose-rate brachytherapy only for breast cancer. Thirty-seven of 39 women enrolled in this pilot study of high-dose-rate brachytherapy (37.2 Gy in 10 fractions b.i.d.) each had thermoluminescent dosimetry (TLD) at 5 points on the skin of the breast overlying the implant volume. Skin changes at TLD dose points and fibrosis at the lumpectomy site were documented every 6 to 12 months posttreatment using a standardized physician-rated cosmesis questionnaire. The relationships between TLD dose and acute skin reaction, pigmentation, or telangiectasia at 5 years were analyzed using the GEE algorithm and the GENMOD procedure in the SAS statistical package. Fisher's exact test was used to determine whether there were any significant associations between acute skin reaction and late pigmentation or telangiectasia or between the volumes encompassed by various isodoses and fibrosis or fat necrosis. The median TLD dose per fraction (185 dose points) multiplied by 10 was 9.2 Gy. In all 37 patients, acute skin reaction Grade 1 or higher was observed at 5.9% (6 of 102) of dose points receiving 10 Gy or less vs. 44.6% (37 of 83) of dose points receiving more than 10 Gy (p skin reaction was also significantly associated with development of Grade 1 or more pigmentation or telangiectasia at 60 months. This association was most significant for acute reaction and telangiectasia directly over the lumpectomy site (p brachytherapy to the lumpectomy site, TLD skin dose was significantly related to acute skin reaction and to pigmentation and telangiectasia at 60 months. An acute skin reaction was also significantly associated with the development of telangiectasia at 60 months. TLD skin dose measurement may allow modification of the brachytherapy implant geometry (dwell times and position) to minimize late skin toxicity.

  4. American Society for Radiation Oncology (ASTRO) and American College of Radiology (ACR) practice guideline for the performance of high-dose-rate brachytherapy.

    Science.gov (United States)

    Erickson, Beth A; Demanes, D Jeffrey; Ibbott, Geoffrey S; Hayes, John K; Hsu, I-Chow J; Morris, David E; Rabinovitch, Rachel A; Tward, Jonathan D; Rosenthal, Seth A

    2011-03-01

    High-Dose-Rate (HDR) brachytherapy is a safe and efficacious treatment option for patients with a variety of different malignancies. Careful adherence to established standards has been shown to improve the likelihood of procedural success and reduce the incidence of treatment-related morbidity. A collaborative effort of the American College of Radiology (ACR) and American Society for Therapeutic Radiation Oncology (ASTRO) has produced a practice guideline for HDR brachytherapy. The guideline defines the qualifications and responsibilities of all the involved personnel, including the radiation oncologist, physicist and dosimetrists. Review of the leading indications for HDR brachytherapy in the management of gynecologic, thoracic, gastrointestinal, breast, urologic, head and neck, and soft tissue tumors is presented. Logistics with respect to the brachytherapy implant procedures and attention to radiation safety procedures and documentation are presented. Adherence to these practice guidelines can be part of ensuring quality and safety in a successful HDR brachytherapy program. Copyright © 2011. Published by Elsevier Inc.

  5. Prostate Specific Antigen (PSA as Predicting Marker for Clinical Outcome and Evaluation of Early Toxicity Rate after High-Dose Rate Brachytherapy (HDR-BT in Combination with Additional External Beam Radiation Therapy (EBRT for High Risk Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Thorsten H. Ecke

    2016-11-01

    Full Text Available High-dose-rate brachytherapy (HDR-BT with external beam radiation therapy (EBRT is a common treatment option for locally advanced prostate cancer (PCa. Seventy-nine male patients (median age 71 years, range 50 to 79 with high-risk PCa underwent HDR-BT following EBRT between December 2009 and January 2016 with a median follow-up of 21 months. HDR-BT was administered in two treatment sessions (one week interval with 9 Gy per fraction using a planning system and the Ir192 treatment unit GammaMed Plus iX. EBRT was performed with CT-based 3D-conformal treatment planning with a total dose administration of 50.4 Gy with 1.8 Gy per fraction and five fractions per week. Follow-up for all patients was organized one, three, and five years after radiation therapy to evaluate early and late toxicity side effects, metastases, local recurrence, and prostate-specific antigen (PSA value measured in ng/mL. The evaluated data included age, PSA at time of diagnosis, PSA density, BMI (body mass index, Gleason score, D’Amico risk classification for PCa, digital rectal examination (DRE, PSA value after one/three/five year(s follow-up (FU, time of follow-up, TNM classification, prostate volume, and early toxicity rates. Early toxicity rates were 8.86% for gastrointestinal, and 6.33% for genitourinary side effects. Of all treated patients, 84.81% had no side effects. All reported complications in early toxicity were grade 1. PSA density at time of diagnosis (p = 0.009, PSA on date of first HDR-BT (p = 0.033, and PSA on date of first follow-up after one year (p = 0.025 have statistical significance on a higher risk to get a local recurrence during follow-up. HDR-BT in combination with additional EBRT in the presented design for high-risk PCa results in high biochemical control rates with minimal side-effects. PSA is a negative predictive biomarker for local recurrence during follow-up. A longer follow-up is needed to assess long-term outcome and toxicities.

  6. Prostate Specific Antigen (PSA) as Predicting Marker for Clinical Outcome and Evaluation of Early Toxicity Rate after High-Dose Rate Brachytherapy (HDR-BT) in Combination with Additional External Beam Radiation Therapy (EBRT) for High Risk Prostate Cancer.

    Science.gov (United States)

    Ecke, Thorsten H; Huang-Tiel, Hui-Juan; Golka, Klaus; Selinski, Silvia; Geis, Berit Christine; Koswig, Stephan; Bathe, Katrin; Hallmann, Steffen; Gerullis, Holger

    2016-11-10

    High-dose-rate brachytherapy (HDR-BT) with external beam radiation therapy (EBRT) is a common treatment option for locally advanced prostate cancer (PCa). Seventy-nine male patients (median age 71 years, range 50 to 79) with high-risk PCa underwent HDR-BT following EBRT between December 2009 and January 2016 with a median follow-up of 21 months. HDR-BT was administered in two treatment sessions (one week interval) with 9 Gy per fraction using a planning system and the Ir192 treatment unit GammaMed Plus iX. EBRT was performed with CT-based 3D-conformal treatment planning with a total dose administration of 50.4 Gy with 1.8 Gy per fraction and five fractions per week. Follow-up for all patients was organized one, three, and five years after radiation therapy to evaluate early and late toxicity side effects, metastases, local recurrence, and prostate-specific antigen (PSA) value measured in ng/mL. The evaluated data included age, PSA at time of diagnosis, PSA density, BMI (body mass index), Gleason score, D'Amico risk classification for PCa, digital rectal examination (DRE), PSA value after one/three/five year(s) follow-up (FU), time of follow-up, TNM classification, prostate volume, and early toxicity rates. Early toxicity rates were 8.86% for gastrointestinal, and 6.33% for genitourinary side effects. Of all treated patients, 84.81% had no side effects. All reported complications in early toxicity were grade 1. PSA density at time of diagnosis (p = 0.009), PSA on date of first HDR-BT (p = 0.033), and PSA on date of first follow-up after one year (p = 0.025) have statistical significance on a higher risk to get a local recurrence during follow-up. HDR-BT in combination with additional EBRT in the presented design for high-risk PCa results in high biochemical control rates with minimal side-effects. PSA is a negative predictive biomarker for local recurrence during follow-up. A longer follow-up is needed to assess long-term outcome and toxicities.

  7. SU-E-T-09: A Clinical Implementation and Optimized Dosimetry Study of Freiberg Flap Skin Surface Treatment in High Dose Rate Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Syh, J; Syh, J; Patel, B; Wu, H; Durci, M [Willis-Knighton Medical Center, Shreveport, LA (United States)

    2015-06-15

    Purpose: This case study was designated to confirm the optimized plan was used to treat skin surface of left leg in three stages. 1. To evaluate dose distribution and plan quality by alternating of the source loading catheters pattern in flexible Freiberg Flap skin surface (FFSS) applicator. 2. To investigate any impact on Dose Volume Histogram (DVH) of large superficial surface target volume coverage. 3. To compare the dose distribution if it was treated with electron beam. Methods: The Freiburg Flap is a flexible mesh style surface mold for skin radiation or intraoperative surface treatments. The Freiburg Flap consists of multiple spheres that are attached to each other, holding and guiding up to 18 treatment catheters. The Freiburg Flap also ensures a constant distance of 5mm from the treatment catheter to the surface. Three treatment trials with individual planning optimization were employed: 18 channels, 9 channels of FF and 6 MeV electron beam. The comparisons were highlighted in target coverage, dose conformity and dose sparing of surrounding tissues. Results: The first 18 channels brachytherapy plan was generated with 18 catheters inside the skin-wrapped up flap (Figure 1A). A second 9 catheters plan was generated associated with the same calculation points which were assigned to match prescription for target coverage as 18 catheters plan (Figure 1B). The optimized inverse plan was employed to reduce the dose to adjacent structures such as tibia or fibula. The comparison of DVH’s was depicted on Figure 2. External beam of electron RT plan was depicted in Figure 3. Overcall comparisons among these three were illustrated in Conclusion: The 9-channel Freiburg flap flexible skin applicator offers a reasonably acceptable plan without compromising the coverage. Electron beam was discouraged to use to treat curved skin surface because of low target coverage and high dose in adjacent tissues.

  8. Chemoradiation in cervical cancer with cisplatin and high-dose rate brachytherapy combined with external beam radiotherapy. Results of a phase-II study

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, H.G.; Laban, C.; Puschmann, D.; Koelbl, H. [Dept. of Gynecology, Martin-Luther Univ. Halle-Wittenberg (Germany); Kuhnt, T.; Pigorsch, S.; Dunst, J.; Haensgen, G. [Dept. of Radiotherapy, Martin-Luther Univ. Halle-Wittenberg (Germany)

    2002-07-01

    Background: In 1999, five randomized studies demonstrated that chemoradiation with cisplatin and low-dose rate (LDR) brachytherapy has a benefit in locally advanced cervical cancer and for surgically treated patients in high-risk situations. We evaluated the safety and efficacy of concomitant chemoradiation with cisplatin and high-dose rate (HDR) brachytherapy in patients with cervical cancer. Patients and Method: 27 patients were included in our phase-II trial: 13 locally advanced cases (group A) and 14 adjuvant-therapy patients in high-risk situations (group B). A definitive radiotherapy was performed with 25 fractions of external beam therapy (1.8 Gy per fraction/middle shielded after eleven fractions). Brachytherapy was delivered at HDR schedules with 7 Gy in point A per fraction (total dose 35 Gy) in FIGO Stages IIB-IIIB. The total dose of external and brachytherapy was 70 Gy in point A and 52-54 Gy in point B. All patients in stage IVA were treated without brachytherapy. Adjuvant radiotherapy was performed with external beam radiotherapy of the pelvis with 1.8 Gy single-dose up to 50.4 Gy. Brachytherapy was delivered at HDR schedules with two fractions of 5 Gy only in patients with tumor-positive margins or tumor involvement of the upper vagina. The chemotherapeutic treatment schedule provided six courses of cisplatin 40 mg/m{sup 2} weekly recommended in the randomized studies GOG-120 and -123. Results: A total of 18/27 patients (66.7%) completed all six courses of chemotherapy. Discontinuation of radiotherapy due to therapy-related morbidity was not necessary in the whole study group. G3 leukopenia (29.6%) was the only relevant acute toxicity. There were no differences in toxicity between group A and B. Serious late morbidity occurred in 2/27 patients (7.4%). 12/13 patients (92.3%) with IIB-IVA cervical cancer showed a complete response (CR). 13/14 adjuvant cases (92.8%) are free of recurrence (median follow up: 19.1 months). Conclusion: Concomitant

  9. Real-Time Verification of a High-Dose-Rate Iridium 192 Source Position Using a Modified C-Arm Fluoroscope

    Energy Technology Data Exchange (ETDEWEB)

    Nose, Takayuki, E-mail: nose-takayuki@nms.ac.jp [Department of Radiation Oncology, Nippon Medical School Tamanagayama Hospital, Tama (Japan); Chatani, Masashi [Department of Radiation Oncology, Osaka Rosai Hospital, Sakai (Japan); Otani, Yuki [Department of Radiology, Kaizuka City Hospital, Kaizuka (Japan); Teshima, Teruki [Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka (Japan); Kumita, Shinichirou [Department of Radiology, Nippon Medical School Hospital, Tokyo (Japan)

    2017-03-15

    Purpose: High-dose-rate (HDR) brachytherapy misdeliveries can occur at any institution, and they can cause disastrous results. Even a patient's death has been reported. Misdeliveries could be avoided with real-time verification methods. In 1996, we developed a modified C-arm fluoroscopic verification of an HDR Iridium 192 source position prevent these misdeliveries. This method provided excellent image quality sufficient to detect errors, and it has been in clinical use at our institutions for 20 years. The purpose of the current study is to introduce the mechanisms and validity of our straightforward C-arm fluoroscopic verification method. Methods and Materials: Conventional X-ray fluoroscopic images are degraded by spurious signals and quantum noise from Iridium 192 photons, which make source verification impractical. To improve image quality, we quadrupled the C-arm fluoroscopic X-ray dose per pulse. The pulse rate was reduced by a factor of 4 to keep the average exposure compliant with Japanese medical regulations. The images were then displayed with quarter-frame rates. Results: Sufficient quality was obtained to enable observation of the source position relative to both the applicators and the anatomy. With this method, 2 errors were detected among 2031 treatment sessions for 370 patients within a 6-year period. Conclusions: With the use of a modified C-arm fluoroscopic verification method, treatment errors that were otherwise overlooked were detected in real time. This method should be given consideration for widespread use.

  10. Real-Time Verification of a High-Dose-Rate Iridium 192 Source Position Using a Modified C-Arm Fluoroscope.

    Science.gov (United States)

    Nose, Takayuki; Chatani, Masashi; Otani, Yuki; Teshima, Teruki; Kumita, Shinichirou

    2017-03-15

    High-dose-rate (HDR) brachytherapy misdeliveries can occur at any institution, and they can cause disastrous results. Even a patient's death has been reported. Misdeliveries could be avoided with real-time verification methods. In 1996, we developed a modified C-arm fluoroscopic verification of an HDR Iridium 192 source position prevent these misdeliveries. This method provided excellent image quality sufficient to detect errors, and it has been in clinical use at our institutions for 20 years. The purpose of the current study is to introduce the mechanisms and validity of our straightforward C-arm fluoroscopic verification method. Conventional X-ray fluoroscopic images are degraded by spurious signals and quantum noise from Iridium 192 photons, which make source verification impractical. To improve image quality, we quadrupled the C-arm fluoroscopic X-ray dose per pulse. The pulse rate was reduced by a factor of 4 to keep the average exposure compliant with Japanese medical regulations. The images were then displayed with quarter-frame rates. Sufficient quality was obtained to enable observation of the source position relative to both the applicators and the anatomy. With this method, 2 errors were detected among 2031 treatment sessions for 370 patients within a 6-year period. With the use of a modified C-arm fluoroscopic verification method, treatment errors that were otherwise overlooked were detected in real time. This method should be given consideration for widespread use. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Development of a new flexible electrode for interstitial hyperthermia compatible with a high dose rate {sup 192}Ir remote after-loading system

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, Nobue; Moriyama, Masahiro; Kitagaki, Hajime [Shimane Medical Univ., Izumo (Japan); Kato, Hirokazu; Kasai, Toshifumi; Sugimura, Kazuro

    1999-09-01

    We developed a new electrode for induction of RF interstitial hyperthermia combined with a high dose rate (HDR) {sup 192}Ir remote after-loading system (RALS), and studied the heating characteristics of using an agar phantom. This hyperthermia induction system consists of two types of electrodes: a flexible internal electrode made of coil-spring (1.14 mm in diameter, 5 or 10-cm in length) which can be inserted into a 5-Fr. nylon RALS catheter; and a rectangular external electrode made of copper plate. The results from computer simulation showed that overheating does not occur in proximity to the external electrode. Experiments using the phantom showed that with application of a 5 W at 13.56 MHz RF signal for 2 min, the temperature rose uniformly along the electrode, while no overheating around the outer electrode was observed. The specific absorption rate (SAR) values at 1-cm and 1.5-cm distance were about 25% and 7%, respectively, with 100% defined as the value at the electrode. The electrodes we developed efficiently provide a uniform distribution of increasing temperature, suggesting that their use may make it possible to avoid the trauma of catheter re-insertion. (author)

  12. Clinical outcomes with high-dose-rate surface mould brachytherapy for intra-oral and skin malignancies involving head and neck region.

    Science.gov (United States)

    Budrukkar, Ashwini; Dasgupta, Archya; Pandit, Prakash; Laskar, Sarbani Ghosh; Murthy, Vedang; Upreti, Ritu Raj; Gupta, Tejpal; Dholam, Kanchan; Agarwal, Jai Prakash

    2017-06-01

    The literature and experience of high-dose-rate (HDR) surface mould brachytherapy (SMB) in head and neck cancer is sparse. We report our institutional experience of SMB for such tumours. Thirty-five patients with malignant localized early T1/T2, N0 (21 intra-oral and 14 skin) tumours treated with SMB during 2008-2014 were analyzed. Treatment was delivered using HDR (192)Ir source to a median dose of 49 Gy (range, 38.5-52.5 Gy) as radical brachytherapy and 18 Gy (range, 15.5-30 Gy) as boost with 3-4 Gy/fraction twice daily using customized surface mould. Median follow-up was 52 months (range, 6 to 98 months). Local control (LC) for skin tumours and intra-oral malignancies at 5 years were 92% and 76%, respectively. Five-year cause specific survival was 92%. For T1 and T2 tumours, 5 year LC was 94.2% and 68.2%, respectively. T stage (p brachytherapy results in excellent LC rates for skin tumours and T1 intraoral tumours when considered as radical treatment, and preferable to consider it as a boost for T2 intraoral tumours. Surface mould brachytherapy results in excellent organ and function preservation.

  13. Clinical outcomes with high-dose-rate surface mould brachytherapy for intra-oral and skin malignancies involving head and neck region

    Directory of Open Access Journals (Sweden)

    Ashwini Budrukkar

    2017-03-01

    Full Text Available Purpose : The literature and experience of high-dose-rate (HDR surface mould brachytherapy (SMB in head and neck cancer is sparse. We report our institutional experience of SMB for such tumours. Material and methods: Thirty-five patients with malignant localized early T1/T2, N0 (21 intra-oral and 14 skin tumours treated with SMB during 2008-2014 were analyzed. Treatment was delivered using HDR 192Ir source to a median dose of 49 Gy (range, 38.5-52.5 Gy as radical brachytherapy and 18 Gy (range, 15.5-30 Gy as boost with 3-4 Gy/fraction twice daily using customized surface mould. Results : Median follow-up was 52 months (range, 6 to 98 months. Local control (LC for skin tumours and intra-oral malignancies at 5 years were 92% and 76%, respectively. Five-year cause specific survival was 92%. For T1 and T2 tumours, 5 year LC was 94.2% and 68.2%, respectively. T stage (p < 0.04 and dose/fractions (p < 0.003 were the only significant prognostic factors for LC on univariate analysis. Conclusions : Surface mould brachytherapy results in excellent LC rates for skin tumours and T1 intraoral tumours when considered as radical treatment, and preferable to consider it as a boost for T2 intraoral tumours. Surface mould brachytherapy results in excellent organ and function preservation.

  14. A dosimetric study of polyethylene glycol hydrogel in 200 prostate cancer patients treated with high-dose rate brachytherapy±intensity modulated radiation therapy.

    Science.gov (United States)

    Strom, Tobin J; Wilder, Richard B; Fernandez, Daniel C; Mellon, Eric A; Saini, Amarjit S; Hunt, Dylan C; Pow-Sang, Julio M; Spiess, Phillipe E; Sexton, Wade J; Poch, Michael A; Biagioli, Matthew C

    2014-04-01

    We sought to analyze the effect of polyethylene glycol (PEG) hydrogel on rectal doses in prostate cancer patients undergoing radiotherapy. Between July 2009 and April 2013, we treated 200 clinically localized prostate cancer patients with high-dose rate (HDR) brachytherapy±intensity modulated radiation therapy. Half of the patients received a transrectal ultrasound (TRUS)-guided transperineal injection of 10mL PEG hydrogel (DuraSeal™ Spinal Sealant System; Covidien, Mansfield, MA) in their anterior perirectal fat immediately prior to the first HDR brachytherapy treatment and 5mL PEG hydrogel prior to the second HDR brachytherapy treatment. Prostate, rectal, and bladder doses and prostate-rectal distances were calculated based upon treatment planning CT scans. There was a success rate of 100% (100/100) with PEG hydrogel implantation. PEG hydrogel significantly increased the prostate-rectal separation (mean±SD, 12±4mm with gel vs. 4±2mm without gel, phydrogel temporarily displaced the rectum away from the prostate by an average of 12mm and led to a significant reduction in rectal radiation doses, regardless of BMI. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  15. A prospective cohort study to compare treatment results between 2 fractionation schedules of high-dose-rate intracavitary brachytherapy (HDR-ICBT) in patients with cervical cancer.

    Science.gov (United States)

    Huang, Eng-Yen; Sun, Li-Min; Lin, Hao; Lan, Jen-Hong; Chanchien, Chan-Chao; Huang, Yu-Jie; Wang, Chang-Yu; Wang, Chong-Jong

    2013-01-01

    To compare the treatment results of 2 fractionation schedules for high-dose-rate intracavitary brachytherapy (HDR-ICBT) in patients with cervical cancer. From June 2001 through January 2008, 267 patients with stage IB-IVA cervical cancer were enrolled in the study. All patients underwent 4-field pelvic irradiation and HDR-ICBT. The median central and parametrial doses were 39.6 Gy and 45 Gy, respectively. Patient underwent either 6 Gy×4 (HDR-4) (n=144) or 4.5 Gy×6 (HDR-6) (n=123) to point A of ICBT using 192Ir isotope twice weekly. The rates of overall survival, locoregional failure, distant metastasis, proctitis, cystitis, and enterocolitis were compared between HDR-4 and HDR-6. There were no significant differences in the demographic data between HDR-4 and HDR-6 except for total treatment time. The 5-year proctitis rates were 23.0% and 21.5% in HDR-4 and HDR-6 (P=.399), respectively. The corresponding rates of grade 2-4 proctitis were 18.7% and 9.6% (P=.060). The corresponding rates of grades 3-4 proctitis were 5.2% and 1.3% (P=.231). Subgroup analysis revealed that HDR-4 significantly increased grade 2-4 proctitis in patients aged≥62 years old (P=.012) but not in patients agedschedules. The small fraction size of HDR-ICBT is associated with grade 2 proctitis without compromise of prognosis in elderly patients. This schedule is suggested for patients who tolerate an additional 2 applications of HDR-ICBT. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Cosmetic Analysis Following Breast-Conserving Surgery and Adjuvant High-Dose-Rate Interstitial Brachytherapy for Early-Stage Breast Cancer: A Prospective Clinical Study

    Energy Technology Data Exchange (ETDEWEB)

    Garsa, Adam A.; Ferraro, Daniel J.; DeWees, Todd [Department of Radiation Oncology, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Margenthaler, Julie A. [Department of Surgery, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Naughton, Michael [Department of Medicine, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Aft, Rebecca [Department of Surgery, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Department of Surgery, John Cochran Veterans Hospital, St. Louis, Missouri (United States); Gillanders, William E.; Eberlein, Timothy [Department of Surgery, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Matesa, Melissa A. [Department of Radiation Oncology, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Zoberi, Imran, E-mail: izoberi@radonc.wustl.edu [Department of Radiation Oncology, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States)

    2013-03-15

    Purpose: To prospectively evaluate cosmetic outcomes in women treated with accelerated partial breast irradiation using high-dose-rate interstitial brachytherapy for early-stage breast cancer. Methods and Materials: Between 2004 and 2008, 151 patients with early-stage breast cancer were enrolled in a phase 2 prospective clinical trial. Eligible patients had stage Tis-T2 tumors of ≤3 cm that were excised with negative margins and with no nodal involvement. Patients received 3.4 Gy twice daily to a total dose of 34 Gy. Both the patients and the treating radiation oncologist qualitatively rated cosmesis as excellent, good, fair, or poor over time and ascribed a cause for changes in cosmesis. Cosmetic outcome was evaluated quantitatively by percentage of breast retraction assessment (pBRA). Patients also reported their satisfaction with treatment over time. Results: Median follow-up was 55 months. The rates of excellent-to-good cosmesis reported by patients and the treating radiation oncologist were 92% and 97% pretreatment, 91% and 97% at 3 to 4 months' follow-up, 87% and 94% at 2 years, and 92% and 94% at 3 years, respectively. Breast infection and adjuvant chemotherapy were independent predictors of a fair-to-poor cosmetic outcome at 3 years. Compared to pretreatment pBRA (7.35), there was no significant change in pBRA over time. The volume receiving more than 150 Gy (V150) was the only significant predictor of pBRA. The majority of patients (86.6%) were completely satisfied with their treatment. Conclusions: Patients and the treating physician reported a high rate of excellent-to-good cosmetic outcomes at all follow-up time points. Acute breast infection and chemotherapy were associated with worse cosmetic outcomes. Multicatheter interstitial brachytherapy does not significantly change breast size as measured by pBRA.

  17. High-dose-rate interstitial brachytherapy in early stage oral tongue cancer – 15 year experience from a tertiary care institute

    Directory of Open Access Journals (Sweden)

    Anshuma Bansal

    2016-02-01

    Full Text Available Purpose: To determine outcomes of interstitial high-dose-rate brachytherapy (HDR-BT in patients with early stage oral tongue cancer. Material and methods : Ninety-two patients with stage I and II oral tongue cancer were treated with HDR-BT between 1999 and 2014: brachytherapy alone = 62 (67.4%, and combination of external beam radiotherapy (EBRT and brachytherapy = 30 (32.6%. Median follow-up was 53.5 months. Patterns of failure, overall survival (OS, disease-free survival (DFS, local control rates (LCR, and nodal control rates (NCR were determined. Results : 5-year OS, DFS, LCR, and NCR were 73.2%, 58.2%, 64.2%, and 83.8%, respectively. In total, 43 patients (46.7% failed treatment: isolated local failures = 28 (30.4%, isolated nodal failures = 8 (8.7%, both local and regional failures = 7 (7.6%. While in T1 stage, 5 year LCR were significantly higher in brachytherapy alone group compared to combined EBRT and brachytherapy group (81.7% vs. 62.5%, p = 0.04, the isolated nodal failure rates were not significantly different among the two groups. For T2 stage, NCR were higher in combined EBRT and brachytherapy group compared to brachytherapy alone (92.9% vs. 74.3%. Acute mucositis (grade ≥ 2 was seen more in brachytherapy alone group compared to the combined modality group (87% vs. 66%, and this correlated significantly with the higher biological equivalent dose (BED in the brachytherapy alone group. Conclusions : Our study recommends treating patients with brachytherapy alone in T1 stage, and demonstrates the need for addressing nodal region either by neck dissection or nodal irradiation in T2 stage patients. Also, the study highlights the need for dose escalation (from the doses used in the study in both T1 and T2 stage tumors when using interstitial brachytherapy either as sole modality or as a boost.

  18. Medically inoperable endometrial cancer in patients with a high body mass index (BMI): Patterns of failure after 3-D image-based high dose rate (HDR) brachytherapy.

    Science.gov (United States)

    Acharya, Sahaja; Esthappan, Jacqueline; Badiyan, Shahed; DeWees, Todd A; Tanderup, Kari; Schwarz, Julie K; Grigsby, Perry W

    2016-01-01

    High BMI is a reason for medical inoperability in patients with endometrial cancer in the United States. Definitive radiation is an alternative therapy for these patients; however, data on patterns of failure after definitive radiotherapy are lacking. We describe the patterns of failure after definitive treatment with 3-D image-based high dose rate (HDR) brachytherapy for medically inoperable endometrial cancer. Forty-three consecutive patients with endometrial cancer FIGO stages I-III were treated definitively with HDR brachytherapy with or without external beam radiation therapy. Cumulative incidence of failures was estimated and prognostic variables were identified Mean follow up was 29.7 months. Median BMI was 50.2 kg/m(2) (range: 25.1-104 kg/m(2)). The two-year overall survival was 65.2%. The two-year cumulative incidence of pelvic and distant failures was 8.3% and 13.5%, respectively. Grade 3 disease was associated with a higher risk of all-failures (Hazard Ratio [HR]: 4.67, 95% CI: 1.04-20.9, p=0.044). The incidence of acute Grade 3 GI/GU toxicities was 4.6%. Pelvic failure at two years was less than 10%. Patients with grade 3 disease were more likely to experience disease failure and may warrant closer follow up. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  19. NOTE: Clinical application of a OneDose™ MOSFET for skin dose measurements during internal mammary chain irradiation with high dose rate brachytherapy in carcinoma of the breast

    Science.gov (United States)

    Kinhikar, Rajesh A.; Sharma, Pramod K.; Tambe, Chandrashekhar M.; Mahantshetty, Umesh M.; Sarin, Rajiv; Deshpande, Deepak D.; Shrivastava, Shyam K.

    2006-07-01

    In our earlier study, we experimentally evaluated the characteristics of a newly designed metal oxide semiconductor field effect transistor (MOSFET) OneDose™ in-vivo dosimetry system for Ir-192 (380 keV) energy and the results were compared with thermoluminescent dosimeters (TLDs). We have now extended the same study to the clinical application of this MOSFET as an in-vivo dosimetry system. The MOSFET was used during high dose rate brachytherapy (HDRBT) of internal mammary chain (IMC) irradiation for a carcinoma of the breast. The aim of this study was to measure the skin dose during IMC irradiation with a MOSFET and a TLD and compare it with the calculated dose with a treatment planning system (TPS). The skin dose was measured for ten patients. All the patients' treatment was planned on a PLATO treatment planning system. TLD measurements were performed to compare the accuracy of the measured results from the MOSFET. The mean doses measured with the MOSFET and the TLD were identical (0.5392 Gy, 15.85% of the prescribed dose). The mean dose was overestimated by the TPS and was 0.5923 Gy (17.42% of the prescribed dose). The TPS overestimated the skin dose by 9% as verified by the MOSFET and TLD. The MOSFET provides adequate in-vivo dosimetry for HDRBT. Immediate readout after irradiation, small size, permanent storage of dose and ease of use make the MOSFET a viable alternative for TLDs.

  20. Complete response of endemic Kaposi sarcoma lesions with high-dose-rate brachytherapy: treatment method, results, and toxicity using skin surface applicators.

    Science.gov (United States)

    Kasper, Michael E; Richter, Sam; Warren, Nicholas; Benda, Rashmi; Shang, Charles; Ouhib, Zoubir

    2013-01-01

    To analyze the clinical outcome of Kaposi sarcoma skin lesions treated with high-dose-rate (HDR) brachytherapy in patients with a minimum of 2 years of followup. Between February 2006 and July 2008, all patients with Kaposi sarcoma who received (192)Ir HDR brachytherapy using a skin surface applicator were evaluated for clinical response. Responses to treatment and toxicity were scored using standard criteria. Sixteen cases were collected. Treatment was delivered in four to six fractions, over a period of approximately 12 days. The specified dose ranged from 24 to 35Gy. Median followup the lesion was 41.4 months. No lesion was greater than 2cm. All patients had a complete response to treatment, with no evidence of local recurrence or tumor progression. Thirteen lesions developed Grade 1 and two lesions had Grade 2 acute skin reactions. One patient developed late skin changes with telangiectasias and hypopigmentation. HDR brachytherapy treatment seems to be an effective noninvasive option for patients with small cutaneous Kaposi sarcoma lesions, delivering excellent cosmesis and local control in our small series. Fewer fractions over a shorter period used in our group offer patients more convenience compared with other common regimens. Although HDR is being used more frequently for many surface applications, additional clinical studies with larger numbers of patients and longer followup are needed to confirm the general impression that it is an excellent option for many patients. Copyright © 2013 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  1. Design and development of an inflatable latex balloon to reduce rectal and bladder doses for patients undergoing high dose rate brachytherapy

    Directory of Open Access Journals (Sweden)

    Raghukumar P

    2009-01-01

    Full Text Available Multiple fractions of High Dose Rate (HDR brachytherapy along with external beam therapy is the common method of treatment for cancer of the uterine cervix. Urinary bladder and rectum are the organs at risk (OARs that receive a significant dose during treatment. To reduce the dose to these organs, a majority of hospitals use vaginal gauze packing, as it is a simple, nontraumatic, and easy method. This article describes the design and development of an inflatable balloon that can be used along with the applicator as a substitute for gauze packing. The balloon has two parts-the bladder part (B-part and the rectum part (R-part, both of them are independently inflatable. The selection of the material, its width, length, and thickness are described. A mould/former for making the balloon was designed. Polished steel was used as the mould. This was dipped in specially prepared natural rubber latex (NRL solution several times; the layers were dried and stripped to get the balloon. The composition of NRL and the compounding recipe of the latex are also described. Physical tests like tensile strength, elongation at break, bursting volume, and radiation attenuation caused by the balloon, were checked. Biological tests for assessing type I and type IV allergies, like dermal irritation and skin irritation tests, were also done.

  2. Clinical application of a OneDose MOSFET for skin dose measurements during internal mammary chain irradiation with high dose rate brachytherapy in carcinoma of the breast.

    Science.gov (United States)

    Kinhikar, Rajesh A; Sharma, Pramod K; Tambe, Chandrashekhar M; Mahantshetty, Umesh M; Sarin, Rajiv; Deshpande, Deepak D; Shrivastava, Shyam K

    2006-07-21

    In our earlier study, we experimentally evaluated the characteristics of a newly designed metal oxide semiconductor field effect transistor (MOSFET) OneDose in-vivo dosimetry system for Ir-192 (380 keV) energy and the results were compared with thermoluminescent dosimeters (TLDs). We have now extended the same study to the clinical application of this MOSFET as an in-vivo dosimetry system. The MOSFET was used during high dose rate brachytherapy (HDRBT) of internal mammary chain (IMC) irradiation for a carcinoma of the breast. The aim of this study was to measure the skin dose during IMC irradiation with a MOSFET and a TLD and compare it with the calculated dose with a treatment planning system (TPS). The skin dose was measured for ten patients. All the patients' treatment was planned on a PLATO treatment planning system. TLD measurements were performed to compare the accuracy of the measured results from the MOSFET. The mean doses measured with the MOSFET and the TLD were identical (0.5392 Gy, 15.85% of the prescribed dose). The mean dose was overestimated by the TPS and was 0.5923 Gy (17.42% of the prescribed dose). The TPS overestimated the skin dose by 9% as verified by the MOSFET and TLD. The MOSFET provides adequate in-vivo dosimetry for HDRBT. Immediate readout after irradiation, small size, permanent storage of dose and ease of use make the MOSFET a viable alternative for TLDs.

  3. Image-guided high-dose-rate interstitial brachytherapy – a valuable salvage treatment approach for loco-regional recurrence of papillary thyroid cancer

    Directory of Open Access Journals (Sweden)

    Ning Wu

    2016-04-01

    Full Text Available Purpose : To report the treatment effect of image-guided high-dose-rate (HDR interstitial brachytherapy for refractory recurrence of papillary thyroid cancer (PTC. Case report: This 66-year-old female presented with recurrence 5 years after thyroidectomy for PTC. Despite external irradiation and radioactive 131I, the lesion expanded as 3.7 × 3.0 × 2.3 cm3 and 2.0 × 1.5 × 1.5 cm3. The locoregional recurrent tumor was treated with image-guided HDR interstitial brachytherapy. The total dose of 30 Gy in 6 fractions were delivered on the whole recurrent tumor. Results: Removal of the recurrent tumor was securely achieved by HDR interstitial brachytherapy guided with ultrasound, computed tomography (CT, and magnetic resonance imaging (MRI scanning. The refractory tumor in the patients healed uneventfully after HDR interstitial brachytherapy without recurrence during the 14 months of follow-up. Conclusions : The image-guided HDR interstitial brachytherapy may be a valuable salvage treatment approach for refractory recurrence of PTC.

  4. The Curie-Da Vinci Connection: 5-Years' Experience With Laparoscopic (Robot-Assisted) Implantation for High-Dose-Rate Brachytherapy of Solitary T2 Bladder Tumors.

    Science.gov (United States)

    van der Steen-Banasik, Elzbieta M; Smits, Geert A H J; Oosterveld, Bernard J; Janssen, Theo; Visser, Andries G

    2016-08-01

    To report experience and early results of laparoscopic implantation for interstitial brachytherapy (BT) of solitary bladder tumors and the feasibility of a high-dose-rate (HDR) schedule. From December 2009 to April 2015, 57 patients with a T2 solitary bladder tumor were treated in Arnhem with transurethral bladder resection followed by external beam irradiation, applied to the bladder and regional iliac lymph nodes, 40 Gy in 20 fractions, 5 fractions per week, and within 1 week interstitial HDR BT, in selected cases combined with partial cystectomy and lymph node dissection. The BT catheters were placed via a transabdominal approach with robotic assistance from a Da Vinci robot after a successful initial experience with a nonrobotic laparoscopic approach. The fraction schedule for HDR was 10 fractions of 2.5 Gy, 3 fractions per day. This was calculated to be equivalent to a reference low-dose-rate schedule of 30 Gy in 60 hours. Data for oncologic outcomes and toxicity (Common Toxicity Criteria version 4) were prospectively collected. These modifications resulted in an average postoperative hospitalization of 6 days, minimal blood loss, and no wound healing problems. Two patients had severe acute toxicity: 1 pulmonary embolism grade 4 and 1 cardiac death. Late toxicity was mild (n=2 urogenital grade 3 toxicity). The median follow-up was 2 years. Using cumulative incidence competing risk analysis, the 2-year overall, disease-free, and disease-specific survival and local control rates were 59%, 71%, 87%, and 82%, respectively. The benefits of minimally invasive surgery for implantation of BT catheters and the feasibility of HDR BT in bladder cancer are documented. The patient outcome and adverse events are comparable to the best results published for a bladder-sparing approach. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Phase II Trial of Combined High Dose Rate Brachytherapy and External Beam Radiotherapy for Adenocarcinoma of the Prostate: Preliminary Results of RTOG 0321

    Science.gov (United States)

    Hsu, I-Chow; Bae, Kyounghwa; Shinohara, Katsuto; Pouliot, Jean; Purdy, James; Ibbott, Geoffrey; Speight, Joycelyn; Vigneault, Eric; Ivker, Robert; Sandler, Howard

    2010-01-01

    Purpose To estimate the rate of late grade 3 or greater genitourinary (GU) and gastrointestinal (GI) adverse events (AEs) following treatment with external beam radiation therapy and prostate high dose rate (HDR) brachytherapy. Methods and Materials Each participating institution submitted CT based HDR brachytherapy dosimetry data electronically for credentialing and for each study patient. Patients with locally confined T1c-T3b prostate cancer were eligible for this study. All patients were treated with 45 Gy in 25 fractions from external beam radiotherapy and one HDR implant delivering 19 Gy in 2 fractions. All AEs were graded according to CTCAEv3.0. Late GU/ GI AEs were defined as those occurring more than nine months from the start of the protocol treatment, in patients with at least 18 months of potential follow-up. Results A total of 129 patients from 14 institutions were enrolled in this study. 125 patients were eligible and AE data was available for 112 patients. The pretreatment characteristics of the patients were as follows: T1c-T2c 91%, T3a-T3b 9%, PSA ≤ 10 70%, PSA >10-≤20 30%, GS 2-6 10%, GS 7 72%, and GS 8-10 18%. At a median follow-up time of 29.6 months, 3 acute and 4 late grade 3 GU/GI AEs were reported. The estimated rate of late grade 3-5 GU and GI AE at 18 months was 2.56%. Conclusion This is the first prospective, multi-institutional trial of CT based HDR brachytherapy and external beam radiotherapy. The technique and doses used in this study resulted in acceptable levels of adverse events. PMID:20207506

  6. The small-molecule TNF-α inhibitor, UTL-5g, delays deaths and increases survival rates for mice treated with high doses of cisplatin.

    Science.gov (United States)

    Shaw, Jiajiu; Media, Joseph; Chen, Ben; Valeriote, Fredrick

    2013-09-01

    UTL-5g is a novel small-molecule chemoprotector that lowers hepatotoxicity, nephrotoxicity, and myelotoxicity induced by cisplatin through TNF-α inhibition among other factors. The objective of this study was to investigate whether UTL-5g can reduce the overall acute toxicity of cisplatin and increase cisplatin tolerability in mice. BDF1 female mice were treated individually with UTL-5g (suspended in Ora-Plus) by oral gavage at 60 mg/kg, 30 min before i.p. injection of cisplatin at 10, 15, and 20 mg/kg, respectively, on Day 0. Starting from Day 1, individual mice were again treated daily by the same dose of UTL-5g for 4 consecutive days. Survivals and body weights were monitored. UTL-5g treatment increased the survival rate and delayed the time to death for mice treated with 150 % of the maximum tolerated dose (MTD) of cisplatin (15 mg/kg). Likewise, at 200 % of the MTD of cisplatin (20 mg/kg), treatment of UTL-5g increased the survival rate and delayed the time to death. Treatment of UTL-5g did not have a significant effect on weight loss induced by cisplatin, indicating that body weight may not be a sensitive-enough measure for chemoprotection of UTL-5g against cisplatin. In summary, UTL-5g delayed deaths and increased survival rates of mice treated by high doses of cisplatin, indicating that UTL-5g is capable of reducing the overall acute toxicity of cisplatin and increased cisplatin tolerability in mice; this is in line with the specific chemoprotective effects of UTL-5g previously reported. Further investigation of UTL-5g in combination with cisplatin is warranted.

  7. Outcomes of salvage high-dose-rate brachytherapy with or without external beam radiotherapy for isolated vaginal recurrence of endometrial cancer

    Directory of Open Access Journals (Sweden)

    Shuhei Sekii

    2017-05-01

    Full Text Available Purpose: This study was designed to retrospectively analyze outcomes of high-dose-rate (HDR brachytherapy, with or without external beam radiotherapy (EBRT, in patients with vaginal recurrence of endometrial carcinoma, and to identify factors prognostic of patient outcomes. Material and methods : The medical records of all patients who underwent HDR brachytherapy for initial recurrence in the vagina of endometrial cancer after definitive surgery between 1992 and 2014 were retrospectively reviewed. All patients underwent either intracavitary brachytherapy (ICBT or interstitial brachytherapy (ISBT with or without EBRT. Late toxicity was graded using the EORTC (LENT/SOMA scale, revised in 1995. Results : Thirty-seven patients were identified. The median follow-up time was 48 months (range: 6-225 months. Of these 37 patients, 23 underwent ICBT, 14 underwent ISBT, and 26 underwent EBRT. Tumor size at first examination of initial relapse was significantly larger in the ISBT than in the ICBT group. The 4-year respective overall survival (OS, local control (LC, and progression-free survival (PFS rates in the entire cohort were 81.0%, 77.9%, and 56.8%, respectively. The interval between diagnosis of first recurrence and radiotherapy (< 3 months, ≥ 3 months was a significant predictor of LC and PFS. OS and LC rates did not differ significantly in the ICBT and ISBT groups. Two patients experienced grade 2 rectal bleeding, and four experienced grade 2 hematuria. No grade 3 or higher late complications were observed. Conclusions : Salvage HDR brachytherapy is an optimal for treating vaginal recurrence of endometrial carcinoma with acceptable morbidity. Early radiotherapy, including brachytherapy, should be considered for women who experience vaginal recurrence of endometrial cancer.

  8. Favorable Preliminary Outcomes for Men With Low- and Intermediate-risk Prostate Cancer Treated With 19-Gy Single-fraction High-dose-rate Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Krauss, Daniel J., E-mail: dkrauss@beaumont.edu [Oakland University William Beaumont School of Medicine, Royal Oak, Michigan (United States); Ye, Hong [Oakland University William Beaumont School of Medicine, Royal Oak, Michigan (United States); Martinez, Alvaro A. [21st Century Oncology, Farmington Hills, Michigan (United States); Mitchell, Beth; Sebastian, Evelyn; Limbacher, Amy; Gustafson, Gary S. [Oakland University William Beaumont School of Medicine, Royal Oak, Michigan (United States)

    2017-01-01

    Purpose: To report the toxicity and preliminary clinical outcomes of a prospective trial evaluating 19-Gy, single-fraction high-dose-rate (HDR) brachytherapy for men with low- and intermediate-risk prostate cancer. Methods and Materials: A total of 63 patients were treated according to an institutional review board-approved prospective study of single-fraction HDR brachytherapy. Eligible patients had tumor stage ≤T2a, prostate-specific antigen level ≤15 ng/mL, and Gleason score ≤7. Patients with a prostate gland volume >50 cm{sup 3} and baseline American Urologic Association symptom score >12 were ineligible. Patients underwent transrectal ultrasound-guided transperineal implantation of the prostate, followed by single-fraction HDR brachytherapy. Treatment was delivered using {sup 192}Ir to a dose of 19 Gy prescribed to the prostate, with no additional margin applied. Results: Of the 63 patients, 58 had data available for analysis. Five patients had withdrawn consent during the follow-up period. The median follow-up period was 2.9 years (range 0.3-5.2). The median age was 61.4 years. The median gland volume at treatment was 34.8 cm{sup 3}. Of the 58 patients, 91% had T1 disease, 71% had Gleason score ≤6 (29% with Gleason score 7), and the median pretreatment prostate-specific antigen level was 5.1 ng/mL. The acute and chronic grade 2 genitourinary toxicity incidence was 12.1% and 10.3%, respectively. No grade 3 urinary toxicity occurred. No patients experienced acute rectal toxicity grade ≥2, and 2 experienced grade ≥2 chronic gastrointestinal toxicity. Three patients experienced biochemical failure, yielding a 3-year cumulative incidence estimate of 6.8%. Conclusions: Single-fraction HDR brachytherapy is well-tolerated, with favorable preliminary biochemical and clinical disease control rates.

  9. Image-guided high-dose-rate brachytherapy boost to the dominant intraprostatic lesion using multiparametric magnetic resonance imaging including spectroscopy: Results of a prospective study.

    Science.gov (United States)

    Vigneault, Eric; Mbodji, Khaly; Racine, Louis-Gabriel; Chevrette, Eric; Lavallée, Marie-Claude; Martin, André-Guy; Després, Philippe; Beaulieu, Luc

    To evaluate the long-term outcomes of image-guided high-dose-rate (HDR) brachytherapy boost to the dominant intraprostatic lesion (DIL) using multiparametric magnetic resonance imaging (MRI), including spectroscopy (MRI/magnetic resonance spectroscopy [MRS]). Between December 2009 and March 2011, 20 patients with intermediate-risk prostate cancer underwent multiparametric MRI/MRS protocol before treatment. All patients were treated with an external beam radiotherapy dose of 40 Gy, combined with an HDR brachytherapy boost of 15 Gy. Concurrently, the DIL received a boost of 18 Gy. Missing data during followup were handled with multiple imputations. The median followup was 62 months (range, 23-71 months). Six patients (31%) were classified as favorable intermediate risk and 13 patients (69%) as unfavorable intermediate risk. One patient experienced a prostate-specific antigen biochemical failure, and the 5-year biochemical failure-free survival rate was of 94.7%. The mean International Prostate Symptom Score rose from 7, with respect to baseline, to 10.42 1 month after treatment, and rapidly decreased to 6.97 after 3 months. Grade 1, 2, and 3 acute genitourinary toxicities were reported in 13 (68%), 3 (16%), and 1 (5%) patients, respectively. Grade 1 and 2 late genitourinary toxicities were reported in 9 (53%) and 3 (18%) patients, respectively. Only grade 1 acute and late gastrointestinal toxicities were reported in 4 (21%) and 3 (18%) patients, respectively. Delivering an HDR brachytherapy boost to the DIL using image-guided multiparametric MRI/MRS is feasible with good outcomes for biochemical control, acute and late toxicities, and dosimetric constraints for critical organs. Copyright © 2016 American Brachytherapy Society. All rights reserved.

  10. Updated results of high-dose rate brachytherapy and external beam radiotherapy for locally and locally advanced prostate cancer using the RTOG-ASTRO phoenix definition

    Directory of Open Access Journals (Sweden)

    Antonio C. Pellizzon

    2008-06-01

    Full Text Available PURPOSE: To evaluate the prognostic factors for patients with local or locally advanced prostate cancer treated with external beam radiotherapy (RT and high dose rate brachytherapy (HDR according to the RTOG-ASTRO Phoenix Consensus Conference. MATERIALS AND METHODS: The charts of 209 patients treated between 1997 and 2005 with localized RT and HDR as a boost at the Department of Radiation Oncology, AC Camargo Hospital, Sao Paulo, Brazil were reviewed. Clinical and treatment parameters i.e.: patient's age, Gleason score, clinical stage, initial PSA (iPSA, risk group (RG for biochemical failure, doses of RT and HDR were evaluated. Median age and median follow-up time were 68 and 5.3 years, respectively. Median RT and HDR doses were 45 Gy and 20 Gy. RESULTS: Disease specific survival (DSS at 3.3 year was 94.2%. Regarding RG, for the LR (low risk, IR (intermediate risk and HR (high risk, the DSS rates at 3.3 years were 91.5%, 90.2% and 88.5%, respectively. On univariate analysis prognostic factors related to DSS were RG (p = 0.040, Gleason score ≤ 6 ng/mL (p = 0.002, total dose of HDR ≥ 20 Gy (p < 0.001 On multivariate analysis the only statistical significant predictive factor for biochemical control (bNED was the RG, p < 0.001 (CI - 1.147-3.561. CONCLUSIONS: Although the radiation dose administered to the prostate is an important factor related to bNED, this could not be established with statistical significance in this group of patients. To date , in our own experience, HDR associated to RT could be considered a successful approach in the treatment of prostate cancer.

  11. Electron and high-dose-rate brachytherapy boost in the conservative treatment of stage I-II breast cancer. First results of the randomized Budapest boost trial

    Energy Technology Data Exchange (ETDEWEB)

    Polgar, C.; Fodor, J. [National Institute of Oncology, Department of Radiotherapy, Budapest (Hungary); Orosz, Z. [National Institute of Oncology, Center of Experimental and Human Tumor Pathology Budapest (HU)] [and others

    2002-11-01

    Background and Aims: To evaluate the effect of electron and high-dose-rate brachytherapy (HDR BT) boost on local tumor control (LTC), side effects and cosmesis after breast-conserving surgery (BCS) in a prospective randomized study. Patients and Methods: 207 women with stage I-II breast cancer who underwent BCS were treated by 50 Gy irradiation to the whole breast and then randomly assigned to receive either a boost to the tumor bed (n=104) or no further radiotherapy (n=103). Boost treatments consisted of either 16 Gy electron irradiation (n=52) or 12-14.25 Gy HDR BT (n=52). Breast cancer-related events, side effects, and cosmetic results were assessed. Results: At a median follow-up of 5.3 years, the crude rate of local recurrence was 6.7% (7/104) with and 15.5% (16/103) without boost. The 5-year probability of LTC, relapse-free survival (RFS), and cancer-specific survival (CSS) was 92.7% vs 84.9% (p=0.049), 76.6% vs 66.2% (p=0.044), and 90.4% vs. 82.1% (p=0.053), respectively. There was no significant difference in LTC between patients treated with electron or HDR BT boost (94.2% vs 91.4%; p=0.74). On multivariate analysis, patient age <40 years (RR: 4.53), positive margin status (RR: 4.17), and high mitotic activity index (RR: 3.60) were found to be significant risk factors for local recurrence. The incidence of grade 2-3 side effects was higher in the boost arm (17.3% vs 7.8%; p=0.03). However, the rate of excellent/good cosmetic results was similar for the two arms (85.6% vs 91.3%; p=0.14). Cosmesis was rated as excellent/good in 88.5% of patients treated with HDR BT and 82.7% of patients with electron boost (p=0.29). Conclusions: Boost dose significantly improves LTC and RFS in patients treated with BCS and radiotherapy. In spite of the higher incidence of late side effects in the boost arm, boost dose is strongly recommended for patients at high risk for local recurrence. Positive or close margin status, high mitotic activity index, and young patient age

  12. Salvage prostate re-irradiation using high-dose-rate brachytherapy or focal stereotactic body radiotherapy for local recurrence after definitive radiation therapy.

    Science.gov (United States)

    Mbeutcha, Aurélie; Chauveinc, Laurent; Bondiau, Pierre-Yves; Chand, Marie-Eve; Durand, Matthieu; Chevallier, Daniel; Amiel, Jean; Kee, Daniel Lam Cham; Hannoun-Lévi, Jean-Michel

    2017-03-09

    Optimal management of locally recurrent prostate cancer after definitive radiation therapy is still challenging. With the development of highly accurate radiotherapy devices, prostate salvage re-irradiation might generate lower toxicity rates than classical salvage therapies. We retrospectively evaluated the toxicity and the feasibility of a prostate re-irradiation after definitive radiation therapy failure. Two modalities were investigated: high-dose-rate brachytherapy (HDRB) on whole prostate gland and focal stereotactic radiotherapy (SBRT) using CyberKnife® linac. Between 2011 and 2015, 28 patients with imaged and/or biopsy-proven intra-prostatic recurrence of cancer after definitive radiation therapy underwent a salvage re-irradiation using HDRB (n = 10) or focal SBRT (n = 18). The schedule of re-irradiation was 35 Gy in 5 fractions. Biological response (defined as post-salvage radiation PSA variation) and biochemical no-evidence of disease (bNED) were evaluated in the whole cohort. For patients who had a positive biological response after salvage radiation, biochemical recurrence (BCR) and survival after salvage radiotherapy were evaluated. Post-salvage toxicities were assessed according to the Common Terminology Criteria for Adverse Events (CTCAE) v4.03 and were compared to baseline status. Within a median follow-up of 22.5 months (IQR = 8-42), 9 (90%) patients experienced a positive biological response after salvage HDRB and 5 (50%) remained bNED at the end of the follow-up. Among patients who initially responded to salvage HDRB, the BCR rate was 44.4% after a median interval of 19.5 months (IQR = 11.5-26). Only one patient experienced a transient grade 3 urinary complication. In the SBRT group, the median follow-up was 14.5 months (IQR = 7-23) and 10 (55.6%) out of the 18 patients remained bNED. Among the 15 patients who initially responded to salvage SBRT, 5 (33.3%) experienced a BCR. One patient experienced a transient grade 4

  13. Prostate-specific antigen nadir after high-dose-rate brachytherapy predicts long-term survival outcomes in high-risk prostate cancer

    Directory of Open Access Journals (Sweden)

    Hideyasu Tsumura

    2016-04-01

    Full Text Available Purpose : To evaluate the prognostic value of prostate-specific antigen nadir (nPSA after high-dose-rate (HDR brachytherapy in clinically non-metastatic high-risk prostate cancer patients. Material and methods : Data from 216 patients with high-risk or locally advanced prostate cancer who underwent HDR brachytherapy and external beam radiation therapy with long-term androgen deprivation therapy (ADT between 2003 and 2008 were analyzed. The median prostate-specific antigen (PSA level at diagnosis was 24 ng/ml (range: 3-338 ng/ml. The clinical stage was T1c-2a in 55 cases (26%, T2b-2c in 48 (22%, T3a in 75 (35%, and T3b-4 in 38 (17%. The mean dose to 90% of the planning target volume was 6.3 Gy/fraction of HDR brachytherapy. After 5 fractions, external beam radiation therapy with 10 fractions of 3 Gy was administered. All patients initially underwent neoadjuvant ADT for at least 6 months, and adjuvant ADT was continued for 36 months. The median follow-up was 7 years from the start of radiotherapy. Results : The 7-year PSA relapse-free rate among patients with a post-radiotherapy nPSA level of ≤ 0.02 ng/ml was 94%, compared with 23% for patients with higher nPSA values (HR = 28.57; 95% CI: 12.04-66.66; p < 0.001. Multivariate analysis revealed that the nPSA value after radiotherapy was a significant independent predictor of biochemical failure, whereas pretreatment predictive values for worse biochemical control including higher level of initial PSA, Gleason score ≥ 8, positive biopsy core rate ≥ 67%, and T3b-T4, failed to reach independent predictor status. The 7-year cancer-specific survival rate among patients with a post-radiotherapy nPSA level of ≤ 0.02 ng/ml was 99%, compared with 82% for patients with higher nPSA values (HR = 32.25; 95% CI: 3.401-333.3; p = 0.002. Conclusions : A post-radiotherapy nPSA value of ≤ 0.02 ng/ml was associated with better long-term biochemical tumor control even if patients had pretreatment predictive

  14. The impact of body mass index on rectal dose in locally advanced cervical cancer treated with high-dose-rate brachytherapy.

    Science.gov (United States)

    Lim, Jihoon; Durbin-Johnson, Blythe; Valicenti, Richard; Mathai, Matthew; Stern, Robin L; Mayadev, Jyoti

    2013-01-01

    The impact of body mass index (BMI) on rectal dose in brachytherapy for cervical cancer is unknown. We assessed the association of BMI on rectal dose and lower gastrointestinal (GI) toxicity. Between 2007 and 2010, 51 patients with 97 brachytherapy planning images were reviewed. Volumetric measurements of the maximum percentage, mean percentage, dose to 2cc (D2cc), and dose to 1cc (D1cc) of the rectum, and the Internal Commission on Radiation Units and Measurement (ICRU) rectal point were recorded. Linear mixed effect models, analysis of variance, and regression analyses were used to determine the correlation between multiple observations or to detect a difference in the mean. The GI acute and late toxicity were prospectively recorded and retrospectively analyzed. The average BMI (kg/m(2)) was 27.7 with a range of 17.4-46.6. Among the patients, 8% were morbidly obese, 25% obese, 25% overweight, 40% normal weight, and 2% underweight. The mean D1cc, D2cc, mean rectal dose (%), maximum rectal dose (%), and ICRU rectum was 3.03 Gy, 2.78 Gy, 20%, 60%, and 2.99 Gy, respectively. On multivariate analysis, there was a significant decrease in the D1cc and D2cc rectal dose (p=0.016), ICRU rectal point dose (p=0.022), and mean rectal dose percentage (p=0.021) with an increase in BMI. There was, however, no statistically significant relationship between BMI and GI toxicity. Obesity decreases the rectal dose given in high-dose-rate brachytherapy for locally advanced cervical cancer because of an increase in fatty tissue in the recto-uterine space. There is no significant correlation between BMI and acute or late GI toxicity. Published by Elsevier Inc.

  15. Evaluation of a real-time BeO ceramic fiber-coupled luminescence dosimetry system for dose verification of high dose rate brachytherapy.

    Science.gov (United States)

    Santos, Alexandre M Caraça; Mohammadi, Mohammad; Afshar V, Shahraam

    2015-11-01

    The authors evaluate the capability of a beryllium oxide (BeO) ceramic fiber-coupled luminescence dosimeter, named radioluminescence/optically stimulated luminescence (RL/OSL) BeO FOD, for dosimetric verification of high dose rate (HDR) treatments. The RL/OSL BeO FOD is capable of RL and OSL measurements. The RL/OSL BeO FOD is able to be inserted in 6F proguide needles, used in interstitial HDR treatments. Using a custom built Perspex phantom, 6F proguide needles could be submerged in a water tank at 1 cm separations from each other. A second background fiber was required to correct for the stem effect. The stem effect, dose linearity, reproducibility, depth-dose curves, and angular and temperature dependency of the RL/OSL BeO FOD were characterised using an Ir-192 source. The RL/OSL BeO FOD was also applied to the commissioning of a 10 mm horizontal Leipzig applicator. Both the RL and OSL were found to be reproducible and their percentage depth-dose curves to be in good agreement with those predicted via TG-43. A combined uncertainty of 7.9% and 10.1% (k=1) was estimated for the RL and OSL, respectively. For the 10 mm horizontal Leipzig applicator, measured percentage depth doses were within 5% agreement of the published reference calculations. The output at the 3 mm prescription depth for a 1 Gy delivery was verified to be 0.99±0.08 Gy and 1.01±0.10 Gy by the RL and OSL, respectively. The use of the second background fiber under the current setup means that the two fibers cannot fit into a single 6F needle. Hence, use of the RL is currently not adequate for the purpose of in vivo brachytherapy dosimetry. While not real-time, the OSL is shown to be adequate for in vivo brachytherapy dosimetry.

  16. Early observed transient prostate-specific antigen elevations on a pilot study of external beam radiation therapy and fractionated MRI guided High Dose Rate brachytherapy boost

    Directory of Open Access Journals (Sweden)

    Stall Bronwyn R

    2006-08-01

    Full Text Available Abstract Purpose To report early observation of transient PSA elevations on this pilot study of external beam radiation therapy and magnetic resonance imaging (MRI guided high dose rate (HDR brachytherapy boost. Materials and methods Eleven patients with intermediate-risk and high-risk localized prostate cancer received MRI guided HDR brachytherapy (10.5 Gy each fraction before and after a course of external beam radiotherapy (46 Gy. Two patients continued on hormones during follow-up and were censored for this analysis. Four patients discontinued hormone therapy after RT. Five patients did not receive hormones. PSA bounce is defined as a rise in PSA values with a subsequent fall below the nadir value or to below 20% of the maximum PSA level. Six previously published definitions of biochemical failure to distinguish true failure from were tested: definition 1, rise >0.2 ng/mL; definition 2, rise >0.4 ng/mL; definition 3, rise >35% of previous value; definition 4, ASTRO defined guidelines, definition 5 nadir + 2 ng/ml, and definition 6, nadir + 3 ng/ml. Results Median follow-up was 24 months (range 18–36 mo. During follow-up, the incidence of transient PSA elevation was: 55% for definition 1, 44% for definition 2, 55% for definition 3, 33% for definition 4, 11% for definition 5, and 11% for definition 6. Conclusion We observed a substantial incidence of transient elevations in PSA following combined external beam radiation and HDR brachytherapy for prostate cancer. Such elevations seem to be self-limited and should not trigger initiation of salvage therapies. No definition of failure was completely predictive.

  17. A Prospective Longitudinal Clinical Trial Evaluating Quality of Life After Breast-Conserving Surgery and High-Dose-Rate Interstitial Brachytherapy for Early-Stage Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Garsa, Adam A.; Ferraro, Daniel J.; DeWees, Todd A. [Department of Radiation Oncology, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Deshields, Teresa L. [Department of Medicine, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Margenthaler, Julie A.; Cyr, Amy E. [Department of Surgery, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Naughton, Michael [Department of Medicine, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Aft, Rebecca [Department of Surgery, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Department of Surgery, John Cochran Veterans Hospital, St. Louis, Missouri (United States); Gillanders, William E.; Eberlein, Timothy [Department of Surgery, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Matesa, Melissa A.; Ochoa, Laura L. [Department of Radiation Oncology, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Zoberi, Imran, E-mail: izoberi@radonc.wustl.edu [Department of Radiation Oncology, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States)

    2013-12-01

    Purpose: To prospectively examine quality of life (QOL) of patients with early stage breast cancer treated with accelerated partial breast irradiation (APBI) using high-dose-rate (HDR) interstitial brachytherapy. Methods and Materials: Between March 2004 and December 2008, 151 patients with early stage breast cancer were enrolled in a phase 2 prospective clinical trial. Eligible patients included those with Tis-T2 tumors measuring ≤3 cm excised with negative surgical margins and with no nodal involvement. Patients received 3.4 Gy twice daily to a total dose of 34 Gy. QOL was measured using European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30, version 3.0, and QLQ-BR23 questionnaires. The QLQ-C30 and QLQ-BR23 questionnaires were evaluated during pretreatment and then at 6 to 8 weeks, 3 to 4 months, 6 to 8 months, and 1 and 2 years after treatment. Results: The median follow-up was 55 months. Breast symptom scores remained stable in the months after treatment, and they significantly improved 6 to 8 months after treatment. Scores for emotional functioning, social functioning, and future perspective showed significant improvement 2 years after treatment. Symptomatic fat necrosis was associated with several changes in QOL, including increased pain, breast symptoms, systemic treatment side effects, dyspnea, and fatigue, as well as decreased role functioning, emotional functioning, and social functioning. Conclusions: HDR multicatheter interstitial brachytherapy was well tolerated, with no significant detrimental effect on measured QOL scales/items through 2 years of follow-up. Compared to pretreatment scores, there was improvement in breast symptoms, emotional functioning, social functioning, and future perspective 2 years after treatment.

  18. Posttraumatic Stress Disorder After High-Dose-Rate Brachytherapy for Cervical Cancer With 2 Fractions in 1 Application Under Spinal/Epidural Anesthesia: Incidence and Risk Factors

    Energy Technology Data Exchange (ETDEWEB)

    Kirchheiner, Kathrin, E-mail: kathrin.kirchheiner@meduniwien.ac.at [Department of Radiation Oncology, Comprehensive Cancer Center, Medical University of Vienna/General Hospital of Vienna, Vienna (Austria); Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna, Vienna (Austria); Czajka-Pepl, Agnieszka [Department of Radiation Oncology, Comprehensive Cancer Center, Medical University of Vienna/General Hospital of Vienna, Vienna (Austria); Ponocny-Seliger, Elisabeth [Department of Psychology, Sigmund Freud Private University Vienna, Vienna (Austria); Scharbert, Gisela; Wetzel, Léonore [Department of Anaesthesia, General Intensive Care and Pain Management, Medical University of Vienna/General Hospital of Vienna, Vienna (Austria); Nout, Remi A. [Department of Clinical Oncology, Leiden University Medical Center, Leiden (Netherlands); Sturdza, Alina [Department of Radiation Oncology, Comprehensive Cancer Center, Medical University of Vienna/General Hospital of Vienna, Vienna (Austria); Dimopoulos, Johannes C. [Metropolitan Hospital, Athens (Greece); Dörr, Wolfgang; Pötter, Richard [Department of Radiation Oncology, Comprehensive Cancer Center, Medical University of Vienna/General Hospital of Vienna, Vienna (Austria); Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna, Vienna (Austria)

    2014-06-01

    Purpose: To investigate the psychological consequences of high-dose-rate brachytherapy with 2 fractions in 1 application under spinal/epidural anesthesia in the treatment of locally advanced cervical cancer. Methods and Materials: In 50 patients with locally advanced cervical cancer, validated questionnaires were used for prospective assessment of acute and posttraumatic stress disorder (ASD/PTSD) (Impact of Event Scale–Revision), anxiety/depression (Hospital Anxiety and Depression Scale), quality of life (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30/Cervical Cancer 24), physical functioning (World Health Organization performance status), and pain (visual analogue scale), before and during treatment and 1 week and 3 months after treatment. Qualitative interviews were recorded in open format for content analysis. Results: Symptoms of ASD occurred in 30% of patients 1 week after treatment; and of PTSD in 41% 3 months after treatment in association with this specific brachytherapy procedure. Pretreatment predictive variables explain 82% of the variance of PTSD symptoms. Helpful experiences were the support of the treatment team, psychological support, and a positive attitude. Stressful factors were pain, organizational problems during treatment, and immobility between brachytherapy fractions. Conclusions: The specific brachytherapy procedure, as performed in the investigated mono-institutional setting with 2 fractions in 1 application under spinal/epidural anesthesia, bears a considerable risk of traumatization. The source of stress seems to be not the brachytherapy application itself but the maintenance of the applicator under epidural anesthesia in the time between fractions. Patients at risk may be identified before treatment, to offer targeted psycho-social support. The patients' open reports regarding helpful experiences are an encouraging feedback for the treatment team; the reported stressful

  19. Determination of Prognostic Factors for Vaginal Mucosal Toxicity Associated With Intravaginal High-Dose Rate Brachytherapy in Patients With Endometrial Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Bahng, Agnes Y.; Dagan, Avner [Department of Radiation Oncology, University of Pennsylvania School of Medicine, Philadelphia, PA (United States); Bruner, Deborah W. [University of Pennsylvania School of Nursing, Philadelphia, PA (United States); Lin, Lilie L., E-mail: lin@xrt.upenn.edu [Department of Radiation Oncology, University of Pennsylvania School of Medicine, Philadelphia, PA (United States)

    2012-02-01

    Purpose: The objective of this study was to determine the patient- and treatment-related prognostic factors associated with vaginal toxicity in patients who received intravaginal high dose rate (HDR) brachytherapy alone as adjuvant treatment for endometrial cancer. Secondary goals of this study included a quantitative assessment of optimal dilator use frequency and a crude assessment of clinical predictors for compliant dilator use. Methods and Materials: We retrospectively reviewed the charts of 100 patients with histologically confirmed endometrial cancer who underwent total hysterectomy and bilateral salpingo-oophorectomy with or without lymph node dissection and adjuvant intravaginal brachytherapy between 1995 and 2009 at the Hospital of University of Pennsylvania. The most common treatment regimen used was 21 Gy in three fractions (71 patients). Symptoms of vaginal mucosal toxicity were taken from the history and physical exams noted in the patients' charts and were graded according to the Common Toxicity Criteria for Adverse Events v. 4.02. Results: The incidence of Grade 1 or asymptomatic vaginal toxicity was 33% and Grade 2-3 or symptomatic vaginal toxicity was 14%. Multivariate analysis of age, active length, and dilator use two to three times a week revealed odds ratios of 0.93 (p = 0.013), 3.96 (p = 0.008), and 0.17 (p = 0.032) respectively. Conclusion: Increasing age, vaginal dilator use of at least two to three times a week, and shorter active length were found to be significantly associated with a decreased risk of vaginal stenosis. Future prospective studies are necessary to validate our findings.

  20. Tandem-ring dwell time ratio in Nigeria: dose comparisons of two loading patterns in standard high-dose-rate brachytherapy planning for cervical cancer.

    Science.gov (United States)

    Ibhade, Obed Rachel; Oyeyemi, Oyekunle Emmanuel; Idayat, Akinlade Bidemi; Atara I, Ntekim

    2015-04-01

    In high-dose-rate (HDR) brachytherapy (BT), the source dwell times and dwell positions are essential treatment planning parameters. An optimal choice of these factors is fundamental to obtain the desired target coverage with the lowest achievable dose to the organs at risk (OARs). This study evaluates relevant dose parameters in cervix brachytherapy in order to assess existing tandem-ring dwell time ratio used at the first HDR BT center in Nigeria, and compare it with an alternative source loading pattern. At the Radiotherapy Department, University College Hospital (UCH), Ibadan, Nigeria, a total of 370 standard treatment plans in two alternative sets were generated with HDR basic 2.6 software for one hundred and eighty five cervical cancer patients. The initial 185 individual plans were created for clinical treatment using the tandem-ring dwell time ratio of 1 : 1. Modifying the initial applicator loading ratio, the second set of plans with related dose data were also obtained for study purposes only. Total reference air kerma (TRAK), total time index (TTI), ICRU volume, treatment time, point B dose, ICRU bladder dose, and rectal points dose were evaluated for both sets of plans. The means of all evaluated dose parameters decreased when the existing tandem-ring dwell time ratio (1 : 1) was modified to other dwell weightings (1 : 1 - 3 : 1). These reductions were 13.43% (ICRU volume), 9.83% (rectal dose), 6.68% (point B dose), 6.08% (treatment time), 5.90% (TRAK), 5.88% (TTI), and 1.08% (bladder dose). Correspondingly, coefficients of variation changed by -7.98%, -5.02%, -5.23%, -4.20%, -3.93%, 8.65%, and 3.96% from the existing pattern to the alternative one. Tandem-ring dwell time ratio has significant influence on dosimetric parameters. This study has indicated the need to modify the existing planning approach at UCH.

  1. High-dose-rate brachytherapy with or without intensity modulated radiation therapy as salvage treatment for an isolated, gross local recurrence of prostate cancer post-prostatectomy.

    Science.gov (United States)

    Strom, Tobin J; Wilder, Richard B; Fernandez, Daniel C; Mellon, Eric A; Saini, Amarjit S; Hunt, Dylan C; Biagioli, Matthew C

    2014-01-01

    To evaluate the use of high-dose-rate (HDR) brachytherapy ± intensity modulated radiation therapy (IMRT) as salvage therapy for patients with an isolated, gross local recurrence of prostate cancer after radical prostatectomy. Between October 2009 and May 2013, the authors treated six patients with salvage iridium-192 HDR brachytherapy ± IMRT for biopsy-proven, recurrent prostate cancer post-prostatectomy. In each patient, a pelvic MRI scan or CT scan demonstrated a nodule (range 1.6, 4.7 cm) in the prostate bed. Although prostate-specific antigen values were 0.2-9.5 ng/mL at the time of salvage brachytherapy, there was no pelvic adenopathy on CT or MRI scan, and a bone scan was negative in all cases. Five patients were treated with IMRT to 4500-5040 cGy in 25-28 fractions to the prostate bed followed by two 950 cGy HDR brachytherapy fractions separated by 1-2 weeks. A sixth patient underwent HDR brachytherapy monotherapy consisting of 3800 cGy in four fractions over 3 days. Toxicities were graded according to the Common Terminology Criteria for Adverse Events, version 4.0. Median followup was 9 months (range 3, 40 months). All six patients have been free of androgen deprivation therapy and have an undetectable prostate-specific antigen. One patient developed late Grade 2 urinary incontinence. There was no late grade ≥2 gastrointestinal toxicity. HDR brachytherapy ± IMRT is a safe and effective salvage therapy option for an isolated, gross local recurrence of prostate cancer after radical prostatectomy and merits further study. Copyright © 2014. Published by Elsevier Inc.

  2. A quantitative analysis of two-dimensional manually segmented transrectal ultrasound axial images in planning high dose rate brachytherapy for prostate cancer

    Directory of Open Access Journals (Sweden)

    Dabić-Stanković Kata

    2017-01-01

    Full Text Available Background/Aim. Prostate delineation, pre-planning and catheter implantation procedures, in high-dose rate brachytherapy (HDR-BT, are commonly based on the prostate manually segmented transrectal ultrasound (TRUS images. The aim of this study was to quantitatively analyze the consistency of prostate capsule delineation, done by a single therapist, prior to each HDR-BT fraction and the changes in the shape of the prostate capsule during HDR-BT, using two dimensional (2D TRUS axial image. Methods. A group of 16 patients were treated at the Medical System Belgrade Brachytherapy Department with definitive HDRBT. The total applied median dose of 52 Gy was divided into four individual fractions, each fraction being delivered 2– 3 weeks apart. Real time prostate axial visualization and the manual segmentation prior to each fraction were performed using B-K Medical ultrasound. Quantitative analyses, analysis of an area and shape were applied on 2D-TRUS axial images of the prostate. Area analyses were used to calculate the average value of the cross-sectional area of the prostate image. The parameters of the prostate shape, the fractal dimension and the circularity ratio of the prostate capsule contour were estimated at the maximum axial cross section of the prostate image. Results. The sample group consisted of four phases, each phase being performed prior to the first, second, third and fourth HDR-BT fraction, respectively. Statistical analysis showed that during HDR-BT fractions there were no significant differences in the average value of area, as well as in the maximum shape of prostate capsule. Conclusions. Quantitative analysis of TRUS axial prostate segmented images shows a successful capsule delineation in the series of manually segmented TRUS images, and the prostate maximum shape remaining unchanged during HDR-BT fractions.

  3. Reirradiation of head and neck cancer with high-dose-rate brachytherapy: a customizable intraluminal solution for postoperative treatment of tracheal mucosa recurrence.

    Science.gov (United States)

    Doyle, Laura A; Harrison, Amy S; Cognetti, David; Xiao, Ying; Yu, Yan; Liu, Haisong; Ahn, Peter H; Anné, P Rani; Showalter, Timothy N

    2011-01-01

    Delivering adequate dose to tracheal mucosa recurrence after multiple prior courses of surgery and radiation presented a challenge for radiation delivery. Tumor bed location and size, combined with previous doses to surrounding areas, complicated the use of external beam therapy with either photons or electrons. High-dose-rate (HDR) brachytherapy was explored to provide sufficient dose coverage. A 45-year-old gentleman presented with recurrent head and neck cancer. After undergoing additional excision of gross tumor in the tracheal region, radiation was recommended to improve local control. The region of residual tumor was confined to a small superficial lesion at the posterior-superior aspect of the trachea, involving mucosa located along the bend of the trachea, immediately deep to the stoma. External beam treatment was discussed but was not recommended based on recurrence location in the prior radiation field and patient's flexed chin position. HDR technique with a custom applicator was preferred. A three-dimensional HDR plan based on computed tomography used a single catheter optimized to cover gross tumor volume as delineated by physician. Prescribed dose was 5 Gy/fraction for six fractions (two fractions/wk). The applicator position was verified daily with computed tomography and physician setup approval before treatment. The patient was positioned on a wing board to allow access to the stoma. HDR brachytherapy was well tolerated. Intraluminal HDR brachytherapy is a viable option for providing dose to region inside tracheal stoma. Advantages over photon and electron beam therapy include reduced dose to surrounding tissues previously irradiated, skin dose, and reproducibility of treatment delivery. Copyright © 2011 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  4. Dose comparison between TG-43-based calculations and radiochromic film measurements of the Freiburg flap applicator used for high-dose-rate brachytherapy treatments of skin lesions.

    Science.gov (United States)

    Aldelaijan, Saad; Bekerat, Hamed; Buzurovic, Ivan; Devlin, Phillip; DeBlois, Francois; Seuntjens, Jan; Devic, Slobodan

    Current high-dose-rate brachytherapy skin treatments with the Freiburg flap (FF) applicator are planned with treatment planning systems based on the American Association of Physicists in Medicine TG-43 data sets, which assume full backscatter conditions in dose calculations. The aim of this work is to describe an experimental method based on radiochromic film dosimetry to evaluate dose calculation accuracy during surface treatments with the FF applicator at different depths and bolus thicknesses. Absolute doses were measured using a reference EBT3 radiochromic film dosimetry system within a Solid Water phantom at different depths (0, 0.5, 1, 2, and 3 cm) with respect to the phantom surface. The impact of bolus (up to 3-cm thickness) placed on top of the applicator was investigated for two clinical loadings created using Oncentra MasterPlan: 5 cm × 5 cm and 11 cm × 11 cm. For smaller loading and depths beyond 2 cm and for larger loading and depths beyond 1 cm, the dose difference was less than 3% (±4%). At shallower depths, differences of up to 6% (±4%) at the surface were observed if no bolus was added. The addition of 2-cm bolus for the smaller loading and 1 cm for larger loading minimized the difference to less than 3% (±4%). For typical FF applicator loading sizes, the actual measured dose was 6% (±4%) lower at the skin level when compared with TG-43. Additional bolus above the FF was shown to decrease the dose difference. The consideration of change in clinical practice should be carefully investigated in light of clinical reference data. Copyright © 2017 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  5. SU-F-T-65: AutomaticTreatment Planning for High-Dose Rate (HDR) Brachytherapy with a VaginalCylinder Applicator

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Y; Tan, J; Jiang, S; Albuquerque, K; Jia, X [UT Southwestern Medical Center, Dallas, TX (United States)

    2016-06-15

    Purpose: High dose rate (HDR) brachytherapy treatment planning is conventionally performed in a manual fashion. Yet it is highly desirable to perform computerized automated planning to improve treatment planning efficiency, eliminate human errors, and reduce plan quality variation. The goal of this research is to develop an automatic treatment planning tool for HDR brachytherapy with a cylinder applicator for vaginal cancer. Methods: After inserting the cylinder applicator into the patient, a CT scan was acquired and was loaded to an in-house developed treatment planning software. The cylinder applicator was automatically segmented using image-processing techniques. CTV was generated based on user-specified treatment depth and length. Locations of relevant points (apex point, prescription point, and vaginal surface point), central applicator channel coordinates, and dwell positions were determined according to their geometric relations with the applicator. Dwell time was computed through an inverse optimization process. The planning information was written into DICOM-RT plan and structure files to transfer the automatically generated plan to a commercial treatment planning system for plan verification and delivery. Results: We have tested the system retrospectively in nine patients treated with vaginal cylinder applicator. These cases were selected with different treatment prescriptions, lengths, depths, and cylinder diameters to represent a large patient population. Our system was able to generate treatment plans for these cases with clinically acceptable quality. Computation time varied from 3–6 min. Conclusion: We have developed a system to perform automated treatment planning for HDR brachytherapy with a cylinder applicator. Such a novel system has greatly improved treatment planning efficiency and reduced plan quality variation. It also served as a testbed to demonstrate the feasibility of automatic HDR treatment planning for more complicated cases.

  6. Dosimetric coverage of the prostate, normal tissue sparing, and acute toxicity with high-dose-rate brachytherapy for large prostate volumes

    Energy Technology Data Exchange (ETDEWEB)

    Yang, George; Strom, Tobin J.; Shrinath, Kushagra; Mellon, Eric A.; Fernandez, Daniel C.; Biagioli, Matthew C. [Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL (United States); Wilder, Richard B., E-mail: mcbiagioli@yahoo.com [Cancer Treatment Centers of America, Newnan, GA (United States)

    2015-05-15

    Purpose: to evaluate dosimetric coverage of the prostate, normal tissue sparing, and acute toxicity with HDR brachytherapy for large prostate volumes. Materials and methods: one hundred and two prostate cancer patients with prostate volumes >50 mL (range: 5-29 mL) were treated with high-dose-rate (HDR) brachytherapy ± intensity modulated radiation therapy (IMRT) to 4,500 cGy in 25 daily fractions between 2009 and 2013. HDR brachytherapy monotherapy doses consisted of two 1,350-1,400 cGy fractions separated by 2-3 weeks, and HDR brachytherapy boost doses consisted of two 950-1,150 cGy fractions separated by 4 weeks. Twelve of 32 (38%) unfavorable intermediate risk, high risk, and very high risk patients received androgen deprivation therapy. Acute toxicity was graded according to the Common Terminology Criteria for Adverse Events (CTCAE) version 4. Results: median follow-up was 14 months. Dosimetric goals were achieved in over 90% of cases. Three of 102 (3%) patients developed Grade 2 acute proctitis. No variables were significantly associated with Grade 2 acute proctitis. Seventeen of 102 (17%) patients developed Grade 2 acute urinary retention. American Urological Association (AUA) symptom score was the only variable significantly associated with Grade 2 acute urinary retention (p-0.04). There was no ≥ Grade 3 acute toxicity. Conclusions: dosimetric coverage of the prostate and normal tissue sparing were adequate in patients with prostate volumes >50 mL. Higher pre-treatment AUA symptom scores increased the relative risk of Grade 2 acute urinary retention. However, the overall incidence of acute toxicity was acceptable in patients with large prostate volumes. (author)

  7. SU-G-TeP2-10: Feasibility of Newly Designed Applicator for High Dose Rate Brachytherapy Treatment of Patients with Vaginal Vault Recurrence

    Energy Technology Data Exchange (ETDEWEB)

    Lee, V; Wong, M; Chan, M; Cheung, S; Leung, R; Lee, K; Law, G; Tung, S [Tuen Mun Hospital (Hong Kong); Huang, X; Chui, E; Leung, K [The Chinese University of Hong Kong (Hong Kong); Kwong, D [The University of Hong Kong (Hong Kong)

    2016-06-15

    Purpose: To compare the dose of an in-house 3D-printed gynecology applicator (TMHGA) for vaginal vault recurrence of corpus cancer patients after operation for high dose rate brachytherapy treatment with commercially available applicators. Methods: A newly designed applicator is made from 3D-printing methods using ABSM30i. The isodose of the applicator is compared with Elekta multi-channel (MC) applicator and titanium Rotterdam applicator with coupling central tube and vaginal cylinder (RC). Three plans are created using three applicators in a CT set of water phantom. The applicators are anchored using the applicator library and implant library in the Elekta Oncentra treatment planning system (ver.4.5). The rectum is mimicked by creating a 2cm diameter cylinder, with a distance 1mm posteriorly away from the high risk CTV (HR-CTV). Similarly, the bladder is replicated by a 6cm diameter cylinder with distance 1mm anteriorly from the HR-CTV. Three plans are all normalized 1.5cm superior, 0.5cm anterior and 0.5cm posterior of the applicator surface. By fixing D90 of HR-CTV to 6Gy, the D2cc of rectum and bladder of three plans are compared. Results: The D2cc of the bladder for using TMHGA is lower than MC and RC by 14.0% and 11.9% respectively. While the D2cc of the rectum for using TMHGA is lower than MC and RC by 18.9% and 12.4% respectively. The total treatment time of TMHGA plan is shorter than MC and RC by 11.2% and 12.9%. Conclusion: The applicator created via 3D printing delivers a lower dose to the bladder and the rectum while keeping the same coverage to HR-CTV as other commercially available applicators. Additionally, the new applicator resulted in a reduction of treatment time, which is always welcome.

  8. High-Dose-Rate Brachytherapy and External-Beam Radiotherapy for Hormone-Naieve Low- and Intermediate-Risk Prostate Cancer: A 7-Year Experience

    Energy Technology Data Exchange (ETDEWEB)

    Aluwini, Shafak, E-mail: s.aluwini@erasmusmc.nl [Department of Radiation Oncology, Erasmus MC, Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Rooij, Peter H. van [Department of Radiation Oncology, Erasmus MC, Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Kirkels, Wim J. [Department of Urology, Erasmus MC, Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Jansen, Peter P.; Praag, John O. [Department of Radiation Oncology, Erasmus MC, Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Bangma, Chris H. [Department of Urology, Erasmus MC, Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Kolkman-Deurloo, Inger-Karine K. [Department of Radiation Oncology, Erasmus MC, Daniel den Hoed Cancer Center, Rotterdam (Netherlands)

    2012-08-01

    Purpose: To report clinical outcomes and early and late complications in 264 hormone-naieve patients with low- and intermediate-risk prostate cancer treated with high-dose-rate brachytherapy (HDR-BT) in combination with external-beam radiotherapy (EBRT). Methods and Materials: Between February 2000 and July 2007, 264 patients underwent HDR-BT in combination with EBRT as a treatment for their low- to intermediate-risk prostate cancer. The HDR-BT was performed using ultrasound-based implantation. The total HDR-BT dose was 18 Gy in 3 fractions within 24 h, with a 6-h minimum interval. The EBRT started 2 weeks after HDR-BT and was delivered in 25 fractions of 1.8 Gy to 45 Gy within 5 weeks. Results: After a mean follow-up of 74.5 months, 4 patients (1.5%) showed prostate-specific antigen progression according to the American Society for Radiation Oncology definition and 8 patients (3%) according to the Phoenix definition. A biopsy-proven local recurrence was registered in 1 patient (0.4%), and clinical progression (bone metastases) was documented in 2 patients (0.7%). Seven-year actuarial freedom from biochemical failure was 97%, and 7-year disease-specific survival and overall survival were 100% and 91%, respectively. Toxicities were comparable to other series. Conclusions: Treatment with interstitial HDR-BT plus EBRT shows a low incidence of late complications and a favorable oncologic outcome after 7 years follow-up.

  9. High-dose-rate brachytherapy and external-beam radiotherapy for hormone-naïve low- and intermediate-risk prostate cancer: a 7-year experience.

    Science.gov (United States)

    Aluwini, Shafak; van Rooij, Peter H; Kirkels, Wim J; Jansen, Peter P; Praag, John O; Bangma, Chris H; Kolkman-Deurloo, Inger-Karine K

    2012-08-01

    To report clinical outcomes and early and late complications in 264 hormone-naïve patients with low- and intermediate-risk prostate cancer treated with high-dose-rate brachytherapy (HDR-BT) in combination with external-beam radiotherapy (EBRT). Between February 2000 and July 2007, 264 patients underwent HDR-BT in combination with EBRT as a treatment for their low- to intermediate-risk prostate cancer. The HDR-BT was performed using ultrasound-based implantation. The total HDR-BT dose was 18 Gy in 3 fractions within 24 h, with a 6-h minimum interval. The EBRT started 2 weeks after HDR-BT and was delivered in 25 fractions of 1.8 Gy to 45 Gy within 5 weeks. After a mean follow-up of 74.5 months, 4 patients (1.5%) showed prostate-specific antigen progression according to the American Society for Radiation Oncology definition and 8 patients (3%) according to the Phoenix definition. A biopsy-proven local recurrence was registered in 1 patient (0.4%), and clinical progression (bone metastases) was documented in 2 patients (0.7%). Seven-year actuarial freedom from biochemical failure was 97%, and 7-year disease-specific survival and overall survival were 100% and 91%, respectively. Toxicities were comparable to other series. Treatment with interstitial HDR-BT plus EBRT shows a low incidence of late complications and a favorable oncologic outcome after 7 years follow-up. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Template guided transperineal saturation biopsy of the prostate: lessons for focal and urethra-sparing high-dose-rate brachytherapy for localized prostate cancer

    Directory of Open Access Journals (Sweden)

    Sergey Nikolaevich Novikov

    2016-04-01

    Full Text Available Purpose : The aim of this work is to evaluate results of prostate transperineal saturation biopsy as a guide for focal high-dose-rate brachytherapy in patients with prostate cancer (PCa. Material and methods: Template guided saturation biopsy was performed in 67 primary patients with suspicion for prostate cancer. Biopsy was performed under ultrasonography (US control with the help of brachytherapy grid and 5 mm distance between samples. We put special attention for accurate sampling of prostate in periurethral region. The number of cores varied from 17 to 81 (average 36 cores. Finally, in 40 patients with confirmed prostate cancer results of biopsy were used for brachytherapy planning. Results : Saturation biopsy revealed prostate cancer in 40 of 67 evaluated patients. The extent of biopsy core involvement varied from 5% to 100% (average: 57%. Focal nature of PCa (single unilateral tumor nodule was diagnosed in 10 (25%, multifocal – in another 30 (75% patients. Hemigland invasion was mentioned in 12 (30% cases. Saturation biopsy detected PCa in periurethral cores in 27 (67.5% of 40 evaluated patients. In 10 patients, the extent of involvement in periurethral cores varied between 10% and 50%; in another, 17 observations exceeded 50%. According to results obtained on saturation biopsy, we performed HDR brachytherapy with “urethra low dose tunnel” (D10ur ≤ 80-90% in 13 patients with noninvolved periurethral cores. Theoretically, hemigland brachytherapy was possible in 12 of 40 evaluated patients with PCa. Conclusions : In low risk patients with PCa results of template guided saturation biopsy indicates high frequency (75% of multifocal disease and high probability (67.5% of periurethral invasion. Suitable candidates for focal HDR brachytherapy or irradiation with additional sparing of urethra can be effectively determined with the help of saturation biopsy.

  11. SU-E-J-93: Parametrisation of Dose to the Mucosa of the Anterior Rectal Wall in Transrectal Ultrasound Guided High-Dose-Rate Brachytherapy of the Prostate

    Energy Technology Data Exchange (ETDEWEB)

    Aitkenhead, A; Hamlett, L; Wood, D; Choudhury, A [The Christie Hospital NHS Foundation Trust, Manchester, Greater Manchester (United Kingdom)

    2014-06-01

    Purpose: In high-dose-rate (HDR) brachytherapy of the prostate, radiation is delivered from a number of radioactive sources which are inserted via catheter into the target volume. The rectal mucosa also receives dose during the treatment, which may lead to late toxicity effects. To allow possible links between rectal dose and toxicity to be investigated, suitable methods of parametrising the rectal dose are needed. Methods: During treatment of a series of 95 patients, anatomy and catheter locations were monitored by transrectal ultrasound, and target volume positions were contoured on the ultrasound scan by the therapist. The anterior rectal mucosal wall was identified by contouring the transrectal ultrasound balloon within the ultrasound scan. Source positions and dwell times, along with the dose delivered to the patient were computed using the Oncentra Prostate treatment planning system (TPS). Data for the series of patients were exported from the TPS in Dicom format, and a series of parametrisation methods were developed in a Matlab environment to assess the rectal dose. Results: Contours of the anterior rectal mucosa were voxelised within Matlab to allow the dose to the rectal mucosa to be analysed directly from the 3D dose grid. Dose parametrisations based on dose-surface (DSH) and dose-line (DLH) histograms were obtained. Both lateral and longitudinal extents of the mucosal dose were parametrised using dose-line histograms in the relevant directions. Conclusion: We have developed a series of dose parametrisations for quantifying the dose to the rectal mucosa during HDR prostate brachytherapy which are suitable for future studies investigating potential associations between mucosal dose and late toxicity effects. The geometry of the transrectal probe standardises the rectal anatomy, making this treatment technique particularly suited to studies of this nature.

  12. Metal stent and endoluminal high-dose rate [sup 192]iridium brachytherapy in palliative treatment of malignant biliary tract obstruction. First experiences. Metallgeflecht-Endoprothese und intraluminare High-dose-rate-[sup 192]Iridium-Brachytherapie zur palliativen Behandlung maligner Gallengangsobstruktionen. Erste Erfahrungen

    Energy Technology Data Exchange (ETDEWEB)

    Pakisch, B.; Stuecklschweiger, G.; Poier, E.; Leitner, H.; Poschauko, J.; Hackl, A. (Universitaets-Klinik fuer Radiologie, Abt. fuer Strahlentherapie, Graz (Austria)); Klein, G.E.; Lammer, J.; Hausegger, K.A. (Universitaets-Klinik fuer Radiologie, Abt. fuer Spezielle Roentgendiagnostik und Digitale Bilddiagnostische Verfahren, Graz (Austria))

    1992-06-01

    Since December 1989, 9 patients with inoperable malignant biliary tract obstruction were treated palliatively by a combined modality treatment consisting of placement of a permanent biliary endoprosthesis followed by intraluminal high dose-rate [sup 192]Ir brachytherapy. A dose of 10 Gy was delivered in a hyperfractionated schedule at the point of reference in a distance of 7.5 mm of centre of the source. External small field radiotherapy (50.4 Gy, 1.8 Gy per day, 5 fractions per week) was also given in six cases (M/O, Karnofsky >60%). In 9/9 cases an unrestrained bile flow and an interruption of pruritus was achieved, in 78% (7/9) of cases the duration of palliation was as long as the survival time (median survival time 7.5 months). (orig.).

  13. Triple-tandem high-dose-rate brachytherapy for early-stage medically inoperable endometrial cancer: Initial report on acute toxicity and dosimetric comparison to stereotactic body radiation therapy.

    Science.gov (United States)

    Kauffmann, Greg; Wu, Tianming; Al-Hallaq, Hania; Hasan, Yasmin

    Stereotactic body radiotherapy (SBRT) may be appealing in medically inoperable endometrial cancer to avoid procedural risks. We performed a dosimetric comparison to triple-tandem, high-dose-rate (HDR) brachytherapy. Six consecutive clinical stage I, grade 1-2, medically inoperable endometrial cancer patients were treated with triple-tandem HDR brachytherapy. We report patient factors and acute toxicity. Also, we performed dosimetric comparison to SBRT using both 3D conformal arc (3DArc) and volumetric-modulated arc therapy. D2cc values for normal tissues were calculated and compared to the HDR plans. Median age was 57 years. Patient comorbidities included morbid obesity, congestive heart failure, diabetes, and pulmonary emboli. In three patients who received prior external beam radiation (EBRT), median EBRT and HDR doses were 46 Gy and 20 Gy, respectively. The median dose with HDR brachytherapy monotherapy was 35 Gy. Acute toxicities during EBRT included gastrointestinal (3/3 with grade 1-2) and genitourinary (3/3 with grade 1-2). Acute toxicities during HDR brachytherapy were gastrointestinal (2/6 total with grade 1-2) and genitourinary (2/6 total with grade 1). The mean D2cc/Gy of prescription dose for rectum, sigmoid, and bladder were 0.58, 0.40, and 0.47 respectively. Overall, doses to normal tissues were higher for SBRT plans as compared to HDR. Also, the R50 (ratio of the 50% prescription isodose volume to the PTV) was lowest with HDR brachytherapy. In medically inoperable, clinical stage I endometrial cancer patients with multiple comorbidities, definitive triple-tandem, HDR brachytherapy results in mild acute toxicity. In addition, HDR brachytherapy achieves relatively lower doses to surrounding normal tissues as compared to SBRT. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  14. Temporo-spatial cell-cycle kinetics in HeLa cells irradiated by Ir-192 high dose-rate remote afterloading system (HDR-RALS).

    Science.gov (United States)

    Asahina, Taito; Kaida, Atsushi; Goto, Tatsuaki; Yoshimura, Ryo-Ichi; Sasai, Keisuke; Miura, Masahiko

    2016-07-29

    Intracavitary irradiation plays a pivotal role in definitive radiotherapy for cervical cancer, and the Ir-192 high dose-rate remote afterloading system (HDR-RALS) is often used for this purpose. Under this condition, tumor tissues receive remarkably different absorption doses, with a steep gradient, depending on distance from the radiation source. To obtain temporo-spatial information regarding cell-cycle kinetics in cervical cancer following irradiation by Ir-192 HDR-RALS, we examined HeLa cells expressing the fluorescence ubiquitination-based cell cycle indicator (Fucci), which allowed us to visualize cell-cycle progression. HeLa-Fucci cells, which emit red and green fluorescence in G1 and S/G2/M phases, respectively, were grown on 35-mm dishes and irradiated by Ir-192 HDR-RALS under normoxic and hypoxic conditions. A 6 French (Fr) catheter was used as an applicator. A radiation dose of 6 Gy was prescribed at hypothetical treatment point A, located 20 mm from the radiation source. Changes in Fucci fluorescence after irradiation were visualized for cells from 5 to 20 mm from the Ir-192 source. Several indices, including first green phase duration after irradiation (FGPD), were measured by analysis of time-lapse images. Cells located 5 to 20 mm from the Ir-192 source became green, reflecting arrest in G2, in a similar manner up to 12 h after irradiation; at more distant positions, however, cells were gradually released from the G2 arrest and became red. This could be explained by the observation that the FGPD was longer for cells closer to the radiation source. Detailed observation revealed that FGPD was significantly longer in cells irradiated in the green phase than in the red phase at positions closer to the Ir-192 source. Unexpectedly, the FGPD was significantly longer after irradiation under hypoxia than normoxia, due in large part to the elongation of FGPD in cells irradiated in the red phase. Using HeLa-Fucci cells, we obtained the first temporo

  15. A fast inverse treatment planning strategy facilitating optimized catheter selection in image-guided high-dose-rate interstitial gynecologic brachytherapy.

    Science.gov (United States)

    Guthier, Christian V; Damato, Antonio L; Hesser, Juergen W; Viswanathan, Akila N; Cormack, Robert A

    2017-12-01

    Interstitial high-dose rate (HDR) brachytherapy is an important therapeutic strategy for the treatment of locally advanced gynecologic (GYN) cancers. The outcome of this therapy is determined by the quality of dose distribution achieved. This paper focuses on a novel yet simple heuristic for catheter selection for GYN HDR brachytherapy and their comparison against state of the art optimization strategies. The proposed technique is intended to act as a decision-supporting tool to select a favorable needle configuration. The presented heuristic for catheter optimization is based on a shrinkage-type algorithm (SACO). It is compared against state of the art planning in a retrospective study of 20 patients who previously received image-guided interstitial HDR brachytherapy using a Syed Neblett template. From those plans, template orientation and position are estimated via a rigid registration of the template with the actual catheter trajectories. All potential straight trajectories intersecting the contoured clinical target volume (CTV) are considered for catheter optimization. Retrospectively generated plans and clinical plans are compared with respect to dosimetric performance and optimization time. All plans were generated with one single run of the optimizer lasting 0.6-97.4 s. Compared to manual optimization, SACO yields a statistically significant (P ≤ 0.05) improved target coverage while at the same time fulfilling all dosimetric constraints for organs at risk (OARs). Comparing inverse planning strategies, dosimetric evaluation for SACO and "hybrid inverse planning and optimization" (HIPO), as gold standard, shows no statistically significant difference (P > 0.05). However, SACO provides the potential to reduce the number of used catheters without compromising plan quality. The proposed heuristic for needle selection provides fast catheter selection with optimization times suited for intraoperative treatment planning. Compared to manual optimization, the

  16. Magnetic Resonance Imaging (MRI) Markers for MRI-Guided High-Dose-Rate Brachytherapy: Novel Marker-Flange for Cervical Cancer and Marker Catheters for Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Schindel, Joshua; Muruganandham, Manickam [Department of Radiation Oncology, University of Iowa, Iowa City, Iowa (United States); Pigge, F. Christopher [Department of Chemistry, University of Iowa, Iowa City, Iowa (United States); Anderson, James [Department of Radiation Oncology, University of Iowa, Iowa City, Iowa (United States); Kim, Yusung, E-mail: yusung-kim@uiowa.edu [Department of Radiation Oncology, University of Iowa, Iowa City, Iowa (United States)

    2013-06-01

    Purpose: To present a novel marker-flange, addressing source-reconstruction uncertainties due to the artifacts of a titanium intracavitary applicator used for magnetic resonance imaging (MRI)-guided high-dose-rate (HDR) brachytherapy (BT); and to evaluate 7 different MRI marker agents used for interstitial prostate BT and intracavitary gynecologic HDR BT when treatment plans are guided by MRI. Methods and Materials: Seven MRI marker agents were analyzed: saline solution, Conray-60, copper sulfate (CuSO{sub 4}) (1.5 g/L), liquid vitamin E, fish oil, 1% agarose gel (1 g agarose powder per 100 mL distilled water), and a cobalt–chloride complex contrast (C4) (CoCl{sub 2}/glycine = 4:1). A plastic, ring-shaped marker-flange was designed and tested on both titanium and plastic applicators. Three separate phantoms were designed to test the marker-flange, interstitial catheters for prostate BT, and intracavitary catheters for gynecologic HDR BT. T1- and T2-weighted MRI were analyzed for all markers in each phantom and quantified as percentages compared with a 3% agarose gel background. The geometric accuracy of the MR signal for the marker-flange was measured using an MRI-CT fusion. Results: The CuSO{sub 4} and C4 markers on T1-weighted MRI and saline on T2-weighted MRI showed the highest signals. The marker-flange showed hyper-signals of >500% with CuSO{sub 4} and C4 on T1-weighted MRI and of >400% with saline on T2-weighted MRI on titanium applicators. On T1-weighted MRI, the MRI signal inaccuracies of marker-flanges were measured <2 mm, regardless of marker agents, and that of CuSO{sub 4} was 0.42 ± 0.14 mm. Conclusion: The use of interstitial/intracavitary markers for MRI-guided prostate/gynecologic BT was observed to be feasible, providing accurate source pathway reconstruction. The novel marker-flange can produce extremely intense, accurate signals, demonstrating its feasibility for gynecologic HDR BT.

  17. Development and implementation of a remote audit tool for high dose rate (HDR) Ir-192 brachytherapy using optically stimulated luminescence dosimetry.

    Science.gov (United States)

    Casey, Kevin E; Alvarez, Paola; Kry, Stephen F; Howell, Rebecca M; Lawyer, Ann; Followill, David

    2013-11-01

    The aim of this work was to create a mailable phantom with measurement accuracy suitable for Radiological Physics Center (RPC) audits of high dose-rate (HDR) brachytherapy sources at institutions participating in National Cancer Institute-funded cooperative clinical trials. Optically stimulated luminescence dosimeters (OSLDs) were chosen as the dosimeter to be used with the phantom. The authors designed and built an 8 × 8 × 10 cm(3) prototype phantom that had two slots capable of holding Al2O3:C OSLDs (nanoDots; Landauer, Glenwood, IL) and a single channel capable of accepting all (192)Ir HDR brachytherapy sources in current clinical use in the United States. The authors irradiated the phantom with Nucletron and Varian (192)Ir HDR sources in order to determine correction factors for linearity with dose and the combined effects of irradiation energy and phantom characteristics. The phantom was then sent to eight institutions which volunteered to perform trial remote audits. The linearity correction factor was kL = (-9.43 × 10(-5) × dose) + 1.009, where dose is in cGy, which differed from that determined by the RPC for the same batch of dosimeters using (60)Co irradiation. Separate block correction factors were determined for current versions of both Nucletron and Varian (192)Ir HDR sources and these vendor-specific correction factors differed by almost 2.6%. For the Nucletron source, the correction factor was 1.026 [95% confidence interval (CI) = 1.023-1.028], and for the Varian source, it was 1.000 (95% CI = 0.995-1.005). Variations in lateral source positioning up to 0.8 mm and distal∕proximal source positioning up to 10 mm had minimal effect on dose measurement accuracy. The overall dose measurement uncertainty of the system was estimated to be 2.4% and 2.5% for the Nucletron and Varian sources, respectively (95% CI). This uncertainty was sufficient to establish a ± 5% acceptance criterion for source strength audits under a formal RPC audit program. Trial

  18. High-Dose-Rate Brachytherapy as Monotherapy Delivered in Two Fractions Within One Day for Favorable/Intermediate-Risk Prostate Cancer: Preliminary Toxicity Data

    Energy Technology Data Exchange (ETDEWEB)

    Ghilezan, Michel, E-mail: mghilezan@beaumont.edu [Department of Radiation Oncology, William Beaumont Hospital and Rose Cancer Institute, Royal Oak, Michigan (United States); Martinez, Alvaro; Gustason, Gary; Krauss, Daniel; Antonucci, J. Vito; Chen, Peter; Fontanesi, James; Wallace, Michelle; Ye Hong; Casey, Alyse; Sebastian, Evelyn; Kim, Leonard; Limbacher, Amy [Department of Radiation Oncology, William Beaumont Hospital and Rose Cancer Institute, Royal Oak, Michigan (United States)

    2012-07-01

    Purpose: To report the toxicity profile of high-dose-rate (HDR)-brachytherapy (BT) as monotherapy in a Human Investigation Committee-approved study consisting of a single implant and two fractions (12 Gy Multiplication-Sign 2) for a total dose of 24 Gy, delivered within 1 day. The dose was subsequently increased to 27 Gy (13.5 Gy Multiplication-Sign 2) delivered in 1 day. We report the acute and early chronic genitourinary and gastrointestinal toxicity. Methods and Materials: A total of 173 patients were treated between December 2005 and July 2010. However, only the first 100 were part of the IRB-approved study and out of these, only 94 had a minimal follow-up of 6 months, representing the study population for this preliminary report. All patients had clinical Stage T2b or less (American Joint Committee on Cancer, 5th edition), Gleason score 6-7 (3+4), and prostate-specific antigen level of {<=}12 ng/mL. Ultrasound-guided HDR-BT with real-time dosimetry was used. The prescription dose was 24 Gy for the first 50 patients and 27 Gy thereafter. The dosimetric goals and constraints were the same for the two dose groups. Toxicity was scored using the National Cancer Institute Common Terminology Criteria for Adverse Events, version 3. The highest toxicity scores encountered at any point during follow-up are reported. Results: The median follow-up was 17 months (range, 6-40.5). Most patients had Grade 0-1 acute toxicity. The Grade 2 acute genitourinary toxicity was mainly frequency/urgency (13%), dysuria (5%), hematuria, and dribbling/hesitancy (2%). None of the patients required a Foley catheter at any time; however, 8% of the patients experienced transient Grade 1 diarrhea. No other acute gastrointestinal toxicities were found. The most common chronic toxicity was Grade 2 urinary frequency/urgency in 16% of patients followed by dysuria in 4% of patients; 2 patients had Grade 2 rectal bleeding and 1 had Grade 4, requiring laser treatment. Conclusions: Favorable

  19. Evaluation of a real-time BeO ceramic fiber-coupled luminescence dosimetry system for dose verification of high dose rate brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Alexandre M. Caraça, E-mail: alexandre.santos@adelaide.edu.au [Department of Medical Physics, Royal Adelaide Hospital, Adelaide 5000, Australia and Institute for Photonics and Advanced Sensing, School of Physical Sciences, University of Adelaide, Adelaide 5005 (Australia); Mohammadi, Mohammad [Department of Medical Physics, Royal Adelaide Hospital, Adelaide 5000, Australia and Department of Medical Physics, Faculty of Medicine, Hamadan University of Medical Sciences, Hamadan 65167-3-8736 (Iran, Islamic Republic of); Shahraam, Afshar V. [Laser Physics and Photonic Devices Laboratories, School of Engineering, The University of South Australia, Adelaide 5095 (Australia); Institute for Photonics and Advanced Sensing, School of Physical Sciences, University of Adelaide, Adelaide 5005 (Australia)

    2015-11-15

    Purpose: The authors evaluate the capability of a beryllium oxide (BeO) ceramic fiber-coupled luminescence dosimeter, named radioluminescence/optically stimulated luminescence (RL/OSL) BeO FOD, for dosimetric verification of high dose rate (HDR) treatments. The RL/OSL BeO FOD is capable of RL and OSL measurements. Methods: The RL/OSL BeO FOD is able to be inserted in 6F proguide needles, used in interstitial HDR treatments. Using a custom built Perspex phantom, 6F proguide needles could be submerged in a water tank at 1 cm separations from each other. A second background fiber was required to correct for the stem effect. The stem effect, dose linearity, reproducibility, depth-dose curves, and angular and temperature dependency of the RL/OSL BeO FOD were characterised using an Ir-192 source. The RL/OSL BeO FOD was also applied to the commissioning of a 10 mm horizontal Leipzig applicator. Results: Both the RL and OSL were found to be reproducible and their percentage depth-dose curves to be in good agreement with those predicted via TG-43. A combined uncertainty of 7.9% and 10.1% (k = 1) was estimated for the RL and OSL, respectively. For the 10 mm horizontal Leipzig applicator, measured percentage depth doses were within 5% agreement of the published reference calculations. The output at the 3 mm prescription depth for a 1 Gy delivery was verified to be 0.99 ± 0.08 Gy and 1.01 ± 0.10 Gy by the RL and OSL, respectively. Conclusions: The use of the second background fiber under the current setup means that the two fibers cannot fit into a single 6F needle. Hence, use of the RL is currently not adequate for the purpose of in vivo brachytherapy dosimetry. While not real-time, the OSL is shown to be adequate for in vivo brachytherapy dosimetry.

  20. Objective method to report planner-independent skin/rib maximal dose in balloon-based high dose rate (HDR) brachytherapy for breast cancer.

    Science.gov (United States)

    Kim, Yongbok; Trombetta, Mark G

    2011-04-01

    An objective method was proposed and compared with a manual selection method to determine planner-independent skin and rib maximal dose in balloon-based high dose rate (HDR) brachytherapy planning. The maximal dose to skin and rib was objectively extracted from a dose volume histogram (DVH) of skin and rib volumes. A virtual skin volume was produced by expanding the skin surface in three dimensions (3D) external to the breast with a certain thickness in the planning computed tomography (CT) images. Therefore, the maximal dose to this volume occurs on the skin surface the same with a conventional manual selection method. The rib was also delineated in the planning CT images and its maximal dose was extracted from its DVH. The absolute (Abdiff = [D(max) Man - D (max)DVH]) and relative (Rediff[%] = 100 x ([D(max)Man-D(max)DVH])/D(max)DVH) maximal skin and rib dose differences between the manual selection method (D(max)Man) and the objective method (D(max)DVH) were measured for 50 balloon-based HDR (25 MammoSite and 25 Contura) patients. The average +/- standard deviation of maximal dose difference was 1.67% +/- 1.69% of the prescribed dose (PD). No statistical difference was observed between MammoSite and Contura patients for both Abdiff and Rediff[%] values. However, a statistically significant difference (p value skin dose difference for both Abdiff (2.30% +/- 1.71% vs 1.05% +/- 1.43%) and Rediff[%] (2.32% +/- 1.79% vs 1.21% +/- 1.41%). In general, rib has a more irregular contour and it is more proximally located to the balloon for 50 HDR patients. Due to the inverse square law factor, more dose difference was observed in higher dose range (D(max) > 90%) compared with lower dose range (D(max) skin and rib can determine the planner-independent maximal dose compared with the manual selection method. However, the difference was < 2% of PD, on average, if appropriate attention is paid to selecting a manual dose point in 3D planning CT images.

  1. Objective method to report planner-independent skin/rib maximal dose in balloon-based high dose rate (HDR) brachytherapy for breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yongbok; Trombetta, Mark G. [Department of Radiation Oncology, Allegheny General Hospital, Pittsburgh, Pennsylvania 15212 (United States) and Drexel University College of Medicine, Allegheny Campus, Pittsburgh, Pennsylvania 15212 (United States)

    2011-04-15

    Purpose: An objective method was proposed and compared with a manual selection method to determine planner-independent skin and rib maximal dose in balloon-based high dose rate (HDR) brachytherapy planning. Methods: The maximal dose to skin and rib was objectively extracted from a dose volume histogram (DVH) of skin and rib volumes. A virtual skin volume was produced by expanding the skin surface in three dimensions (3D) external to the breast with a certain thickness in the planning computed tomography (CT) images. Therefore, the maximal dose to this volume occurs on the skin surface the same with a conventional manual selection method. The rib was also delineated in the planning CT images and its maximal dose was extracted from its DVH. The absolute (Abdiff=|D{sub max}{sup Man}-D{sub max}{sup DVH}|) and relative (Rediff[%]=100x(|D{sub max}{sup Man}-D{sub max}{sup DVH}|)/D{sub max}{sup DVH}) maximal skin and rib dose differences between the manual selection method (D{sub max}{sup Man}) and the objective method (D{sub max}{sup DVH}) were measured for 50 balloon-based HDR (25 MammoSite and 25 Contura) patients. Results: The average{+-}standard deviation of maximal dose difference was 1.67%{+-}1.69% of the prescribed dose (PD). No statistical difference was observed between MammoSite and Contura patients for both Abdiff and Rediff[%] values. However, a statistically significant difference (p value <0.0001) was observed in maximal rib dose difference compared with maximal skin dose difference for both Abdiff (2.30%{+-}1.71% vs 1.05%{+-}1.43%) and Rediff[%] (2.32%{+-}1.79% vs 1.21%{+-}1.41%). In general, rib has a more irregular contour and it is more proximally located to the balloon for 50 HDR patients. Due to the inverse square law factor, more dose difference was observed in higher dose range (D{sub max}>90%) compared with lower dose range (D{sub max}<90%): 2.16%{+-}1.93% vs 1.19%{+-}1.25% with p value of 0.0049. However, the Rediff[%] analysis eliminated the

  2. Comparison of 2D and 3D Imaging and Treatment Planning for Postoperative Vaginal Apex High-Dose Rate Brachytherapy for Endometrial Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Russo, James K. [Department of Radiation Oncology, Hollings Cancer Center, Medical University of South Carolina, Charleston, South Carolina (United States); Armeson, Kent E. [Division of Biostatistics and Epidemiology, Hollings Cancer Center, Medical University of South Carolina, Charleston, South Carolina (United States); Richardson, Susan, E-mail: srichardson@radonc.wustl.edu [Department of Radiation Oncology, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri (United States)

    2012-05-01

    Purpose: To evaluate bladder and rectal doses using two-dimensional (2D) and 3D treatment planning for vaginal cuff high-dose rate (HDR) in endometrial cancer. Methods and Materials: Ninety-one consecutive patients treated between 2000 and 2007 were evaluated. Seventy-one and 20 patients underwent 2D and 3D planning, respectively. Each patient received six fractions prescribed at 0.5 cm to the superior 3 cm of the vagina. International Commission on Radiation Units and Measurements (ICRU) doses were calculated for 2D patients. Maximum and 2-cc doses were calculated for 3D patients. Organ doses were normalized to prescription dose. Results: Bladder maximum doses were 178% of ICRU doses (p < 0.0001). Two-cubic centimeter doses were no different than ICRU doses (p = 0.22). Two-cubic centimeter doses were 59% of maximum doses (p < 0.0001). Rectal maximum doses were 137% of ICRU doses (p < 0.0001). Two-cubic centimeter doses were 87% of ICRU doses (p < 0.0001). Two-cubic centimeter doses were 64% of maximum doses (p < 0.0001). Using the first 1, 2, 3, 4 or 5 fractions, we predicted the final bladder dose to within 10% for 44%, 59%, 83%, 82%, and 89% of patients by using the ICRU dose, and for 45%, 55%, 80%, 85%, and 85% of patients by using the maximum dose, and for 37%, 68%, 79%, 79%, and 84% of patients by using the 2-cc dose. Using the first 1, 2, 3, 4 or 5 fractions, we predicted the final rectal dose to within 10% for 100%, 100%, 100%, 100%, and 100% of patients by using the ICRU dose, and for 60%, 65%, 70%, 75%, and 75% of patients by using the maximum dose, and for 68%, 95%, 84%, 84%, and 84% of patients by using the 2-cc dose. Conclusions: Doses to organs at risk vary depending on the calculation method. In some cases, final dose accuracy appears to plateau after the third fraction, indicating that simulation and planning may not be necessary in all fractions. A clinically relevant level of accuracy should be determined and further research conducted to address

  3. SU-E-T-579: Impact of Cylinder Size in High-Dose Rate Brachytherapy (HDRBT) for Primary Cancer in the Vagina

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, H; Gopalakrishnan, M; Lee, P; Sathiaseelan, V [Department of Radiation Oncology, Northwestern Memorial Hospital, Chicago, IL (United States)

    2014-06-01

    Purpose: To evaluate the dosimetric impact of cylinder size in high dose rate Brachytherapy for primary vaginal cancers. Methods: Patients treated with HDR vaginal vault radiation in a list of cylinders ranging from 2.5 to 4 cm in diameter at 0.5 cm increment were analyzed. All patients’ doses were prescribed at the 0.5 cm from the vaginal surface with different treatment lengths. A series of reference points were created to optimize the dose distribution. The fraction dose was 5.5 Gy, the treatment was repeated for 4 times in two weeks. A cylinder volume was contoured in each case according to the prescribed treatment length, and then expanded to 5 mm to get a volume Cylinder-5mm-exp. A volume of PTV-Eval was obtained by subtracting the cylinder volume from the Cylinder-5mm-exp. The shell volume, PTV-Eval serves as the target volume for dosimetric evaluation. Results: DVH curves and average doses of PTV-Eval were obtained. Our results indicated that the DVH curves shifted toward higher dose side when larger cylinder was used instead of smaller ones. When 3.0 cm cylinder was used instead of 2.5 cm, for 3.0 cm treatment length, the average dose only increased 1%, from 790 to 799 cGy. However, the average doses for 3.5 and 4 cm cylinders respectively are 932 and 1137 cGy at the same treatment length. For 5.0 cm treatment length, the average dose is 741 cGy for 2.5 cm cylinder, and 859 cGy for 3 cm cylinder. Conclusion: Our data analysis suggests that for the vaginal intracavitary HDRBT, the average dose is at least 35% larger than the prescribed dose in the studied cases; the size of the cylinder will impact the dose delivered to the target volume. The cylinder with bigger diameter tends to deliver larger average dose to the PTV-Eval.

  4. Determination of air kerma standard of high dose rate {sup 192}Ir brachytherapy source; Determinacao da taxa de kerma no ar de referencia para {sup 192}Ir de alta taxa de dose para braquiterapia

    Energy Technology Data Exchange (ETDEWEB)

    Pires, E.J.; Alves, C.F.E.; Leite, S.P.; Magalhaes, L.A.G.; David, M.G.; Almeida, C.E. de, E-mail: cfealves@gmail.com [Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil). Lab. de Ciencias Radiologicas; Di Prinzio, R. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    This paper presents the methodology developed by the Laboratorio de Ciencias Radiologicas and presently in use for determining of the air kerma standard of {sup 192}Ir high dose rate sources to calibrate well-type chambers. Uncertainty analysis involving the measurements procedure are presented. (author)

  5. A generic high-dose rate {sup 192}Ir brachytherapy source for evaluation of model-based dose calculations beyond the TG-43 formalism

    Energy Technology Data Exchange (ETDEWEB)

    Ballester, Facundo, E-mail: Facundo.Ballester@uv.es [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100 (Spain); Carlsson Tedgren, Åsa [Department of Medical and Health Sciences (IMH), Radiation Physics, Faculty of Health Sciences, Linköping University, Linköping SE-581 85, Sweden and Department of Medical Physics, Karolinska University Hospital, Stockholm SE-171 76 (Sweden); Granero, Domingo [Department of Radiation Physics, ERESA, Hospital General Universitario, Valencia E-46014 (Spain); Haworth, Annette [Department of Physical Sciences, Peter MacCallum Cancer Centre and Royal Melbourne Institute of Technology, Melbourne, Victoria 3000 (Australia); Mourtada, Firas [Department of Radiation Oncology, Helen F. Graham Cancer Center, Christiana Care Health System, Newark, Delaware 19713 (United States); Fonseca, Gabriel Paiva [Instituto de Pesquisas Energéticas e Nucleares – IPEN-CNEN/SP, São Paulo 05508-000, Brazil and Department of Radiation Oncology (MAASTRO), GROW, School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht 6201 BN (Netherlands); Zourari, Kyveli; Papagiannis, Panagiotis [Medical Physics Laboratory, Medical School, University of Athens, 75 MikrasAsias, Athens 115 27 (Greece); Rivard, Mark J. [Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts 02111 (United States); Siebert, Frank-André [Clinic of Radiotherapy, University Hospital of Schleswig-Holstein, Campus Kiel, Kiel 24105 (Germany); Sloboda, Ron S. [Department of Medical Physics, Cross Cancer Institute, Edmonton, Alberta T6G 1Z2, Canada and Department of Oncology, University of Alberta, Edmonton, Alberta T6G 2R3 (Canada); and others

    2015-06-15

    Purpose: In order to facilitate a smooth transition for brachytherapy dose calculations from the American Association of Physicists in Medicine (AAPM) Task Group No. 43 (TG-43) formalism to model-based dose calculation algorithms (MBDCAs), treatment planning systems (TPSs) using a MBDCA require a set of well-defined test case plans characterized by Monte Carlo (MC) methods. This also permits direct dose comparison to TG-43 reference data. Such test case plans should be made available for use in the software commissioning process performed by clinical end users. To this end, a hypothetical, generic high-dose rate (HDR) {sup 192}Ir source and a virtual water phantom were designed, which can be imported into a TPS. Methods: A hypothetical, generic HDR {sup 192}Ir source was designed based on commercially available sources as well as a virtual, cubic water phantom that can be imported into any TPS in DICOM format. The dose distribution of the generic {sup 192}Ir source when placed at the center of the cubic phantom, and away from the center under altered scatter conditions, was evaluated using two commercial MBDCAs [Oncentra{sup ®} Brachy with advanced collapsed-cone engine (ACE) and BrachyVision ACUROS{sup TM}]. Dose comparisons were performed using state-of-the-art MC codes for radiation transport, including ALGEBRA, BrachyDose, GEANT4, MCNP5, MCNP6, and PENELOPE2008. The methodologies adhered to recommendations in the AAPM TG-229 report on high-energy brachytherapy source dosimetry. TG-43 dosimetry parameters, an along-away dose-rate table, and primary and scatter separated (PSS) data were obtained. The virtual water phantom of (201){sup 3} voxels (1 mm sides) was used to evaluate the calculated dose distributions. Two test case plans involving a single position of the generic HDR {sup 192}Ir source in this phantom were prepared: (i) source centered in the phantom and (ii) source displaced 7 cm laterally from the center. Datasets were independently produced by

  6. A generic high-dose rate (192)Ir brachytherapy source for evaluation of model-based dose calculations beyond the TG-43 formalism.

    Science.gov (United States)

    Ballester, Facundo; Carlsson Tedgren, Åsa; Granero, Domingo; Haworth, Annette; Mourtada, Firas; Fonseca, Gabriel Paiva; Zourari, Kyveli; Papagiannis, Panagiotis; Rivard, Mark J; Siebert, Frank-André; Sloboda, Ron S; Smith, Ryan L; Thomson, Rowan M; Verhaegen, Frank; Vijande, Javier; Ma, Yunzhi; Beaulieu, Luc

    2015-06-01

    In order to facilitate a smooth transition for brachytherapy dose calculations from the American Association of Physicists in Medicine (AAPM) Task Group No. 43 (TG-43) formalism to model-based dose calculation algorithms (MBDCAs), treatment planning systems (TPSs) using a MBDCA require a set of well-defined test case plans characterized by Monte Carlo (MC) methods. This also permits direct dose comparison to TG-43 reference data. Such test case plans should be made available for use in the software commissioning process performed by clinical end users. To this end, a hypothetical, generic high-dose rate (HDR) (192)Ir source and a virtual water phantom were designed, which can be imported into a TPS. A hypothetical, generic HDR (192)Ir source was designed based on commercially available sources as well as a virtual, cubic water phantom that can be imported into any TPS in DICOM format. The dose distribution of the generic (192)Ir source when placed at the center of the cubic phantom, and away from the center under altered scatter conditions, was evaluated using two commercial MBDCAs [Oncentra(®) Brachy with advanced collapsed-cone engine (ACE) and BrachyVision ACUROS™ ]. Dose comparisons were performed using state-of-the-art MC codes for radiation transport, including ALGEBRA, BrachyDose, GEANT4, MCNP5, MCNP6, and PENELOPE2008. The methodologies adhered to recommendations in the AAPM TG-229 report on high-energy brachytherapy source dosimetry. TG-43 dosimetry parameters, an along-away dose-rate table, and primary and scatter separated (PSS) data were obtained. The virtual water phantom of (201)(3) voxels (1 mm sides) was used to evaluate the calculated dose distributions. Two test case plans involving a single position of the generic HDR (192)Ir source in this phantom were prepared: (i) source centered in the phantom and (ii) source displaced 7 cm laterally from the center. Datasets were independently produced by different investigators. MC results were then

  7. SU-F-T-15: Evaluation of 192Ir, 60Co and 169Yb Sources for High Dose Rate Prostate Brachytherapy Inverse Planning Using An Interior Point Constraint Generation Algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Mok Tsze Chung, E; Aleman, D [University of Toronto, Toronto, Ontario (Canada); Safigholi, H; Nicolae, A; Davidson, M; Ravi, A; Song, W [Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Ontario (Canada)

    2016-06-15

    can thus be an alternative to {sup 192}Ir-only in high-dose-rate prostate brachytherapy.

  8. Live birth rates after modified natural cycle compared with high-dose FSH stimulation using GnRH antagonists in poor responders.

    Science.gov (United States)

    Lainas, Trifon G; Sfontouris, Ioannis A; Venetis, Christos A; Lainas, George T; Zorzovilis, Ioannis Z; Tarlatzis, Basil C; Kolibianakis, Efstratios M

    2015-10-01

    Do live birth rates differ between modified natural cycles (MNCs) and cycles using high-dose follicle stimulating hormone (HDFSH) with gonadotrophin-releasing hormone (GnRH) antagonist in poor responder patients? Live birth rates are significantly higher in MNC compared with HDFSH GnRH antagonist cycles in poor responder patients. Previous data on the efficiency of MNC in poor responders are very limited and suggest that MNC in vitro fertilization (IVF) does not offer a realistic solution for parenthood in these patients, since live birth rates are disappointingly low. To date, no studies exist comparing MNC with HDFSH stimulation protocols in poor responders. The present retrospective study included 161 MNCs (106 women in the MNC group) and 164 HDFSH antagonist cycles (136 women in the HDFSH group) performed between January 2008 and December 2013 at Eugonia Assisted Reproduction Unit. The patients included in the study had to fulfill the Bologna criteria for the definition of poor ovarian response. Irrespective of their age, poor responder patients should have a diminished ovarian reserve as shown by low antral follicle count (≤5) and increased basal FSH (>12 IU/l), and one or more previous failed IVF cycles in which ≤3 oocytes were retrieved using a high gonadotrophin dose. Analysis was performed by adjusting for the non-independence of the data. The probability of live birth was significantly higher in the MNC when compared with the HDFSH group (OR: 4.01, 95% CI: 1.14-14.09), after adjusting for basal FSH, female age and cause of infertility, variables which were shown to be associated with the probability of live birth in univariable analysis. MNCs were characterized by significantly lower total gonadotrophin dose (490.0 ± 35.2 IU versus 2826.1 ± 93.4 IU, P live birth in poor responder patients who fulfill the Bologna criteria. However, MNC-IVF is a more patient-friendly approach, with a higher probability of live birth compared with the HDFSH antagonist

  9. The evaluation of a 2D diode array in "magic phantom" for use in high dose rate brachytherapy pretreatment quality assurance.

    Science.gov (United States)

    Espinoza, A; Petasecca, M; Fuduli, I; Howie, A; Bucci, J; Corde, S; Jackson, M; Lerch, M L F; Rosenfeld, A B

    2015-02-01

    High dose rate (HDR) brachytherapy is a treatment method that is used increasingly worldwide. The development of a sound quality assurance program for the verification of treatment deliveries can be challenging due to the high source activity utilized and the need for precise measurements of dwell positions and times. This paper describes the application of a novel phantom, based on a 2D 11 × 11 diode array detection system, named "magic phantom" (MPh), to accurately measure plan dwell positions and times, compare them directly to the treatment plan, determine errors in treatment delivery, and calculate absorbed dose. The magic phantom system was CT scanned and a 20 catheter plan was generated to simulate a nonspecific treatment scenario. This plan was delivered to the MPh and, using a custom developed software suite, the dwell positions and times were measured and compared to the plan. The original plan was also modified, with changes not disclosed to the primary authors, and measured again using the device and software to determine the modifications. A new metric, the "position-time gamma index," was developed to quantify the quality of a treatment delivery when compared to the treatment plan. The MPh was evaluated to determine the minimum measurable dwell time and step size. The incorporation of the TG-43U1 formalism directly into the software allows for dose calculations to be made based on the measured plan. The estimated dose distributions calculated by the software were compared to the treatment plan and to calibrated EBT3 film, using the 2D gamma analysis method. For the original plan, the magic phantom system was capable of measuring all dwell points and dwell times and the majority were found to be within 0.93 mm and 0.25 s, respectively, from the plan. By measuring the altered plan and comparing it to the unmodified treatment plan, the use of the position-time gamma index showed that all modifications made could be readily detected. The MPh was able to

  10. Advantages and implications of high dose rate (HDR) total skin electron irradiation (TSEI) for the management of Mycosis Fungoides. Indian experience.

    Science.gov (United States)

    Parida, Dillip Kumar; Rath, Goura Kishore

    2014-03-01

    Mycosis Fungoides (MF) is an indolent lymphoproliferative disorder affecting dermis caused by abnormal proliferation of CD4+ T-cells. Radiation therapy is the most effective modality of treatment for MF which offers cure in limited stage disease and desirable palliation in advance stage disease. Treating entire skin having many curved surfaces and folds with radiation is the real challenge for the radiation oncologist. Many techniques, dose schedules and modifications in total skin electron irradiation (TSEI) have been tried since 1950s. TSEI treatment is a very time consuming, inconvenient and physically challenging to both patient as well as oncologist. At our center TSEI was performed since 1983 with conventional linear accelerator where the treatment time was prolonged beyond two hours, which was very difficult or the patient, oncologist, technical officer and eating away the machine time hampering the treatment of other patients. From 1998 we shifted to high dose rate (HDR) mode, in order to bring down the treatment time of a single patient every day from two and half hour to 15 min. The reduction of treatment time increases patient compliance and at the same time saved machine time. Between 1998 and 2003, eleven pathological diagnosed MF patients were treated using HDR TSEI. All the patients were male between 40 and 70 years of age, who had the history of having the disease for 7-22 months. Four patients had T2 and seven patients had T3 stage disease with more than 90% skin surface involvement. TSEI was performed with 4 MeV electrons with a daily fraction size of 120 cGy to a total dose of 36 Gy. At the end of 36 Gy, boost dose of 10 Gy was delivered to self shielding regions like sole, scalp and perineum. Considering the treatment related toxicities and consequent treatment interruptions, in the first seven patients, the last four patients were treated using similar HDR TSEI technique with modified treatment schedule, where the treatment was given on

  11. A generic TG-186 shielded applicator for commissioning model-based dose calculation algorithms for high-dose-rate 192 Ir brachytherapy.

    Science.gov (United States)

    Ma, Yunzhi; Vijande, Javier; Ballester, Facundo; Tedgren, Åsa Carlsson; Granero, Domingo; Haworth, Annette; Mourtada, Firas; Fonseca, Gabriel Paiva; Zourari, Kyveli; Papagiannis, Panagiotis; Rivard, Mark J; Siebert, Frank André; Sloboda, Ron S; Smith, Ryan; Chamberland, Marc J P; Thomson, Rowan M; Verhaegen, Frank; Beaulieu, Luc

    2017-11-01

    A joint working group was created by the American Association of Physicists in Medicine (AAPM), the European Society for Radiotherapy and Oncology (ESTRO), and the Australasian Brachytherapy Group (ABG) with the charge, among others, to develop a set of well-defined test case plans and perform calculations and comparisons with model-based dose calculation algorithms (MBDCAs). Its main goal is to facilitate a smooth transition from the AAPM Task Group No. 43 (TG-43) dose calculation formalism, widely being used in clinical practice for brachytherapy, to the one proposed by Task Group No. 186 (TG-186) for MBDCAs. To do so, in this work a hypothetical, generic high-dose rate (HDR) 192 Ir shielded applicator has been designed and benchmarked. A generic HDR 192 Ir shielded applicator was designed based on three commercially available gynecological applicators as well as a virtual cubic water phantom that can be imported into any DICOM-RT compatible treatment planning system (TPS). The absorbed dose distribution around the applicator with the TG-186 192 Ir source located at one dwell position at its center was computed using two commercial TPSs incorporating MBDCAs (Oncentra® Brachy with Advanced Collapsed-cone Engine, ACE™, and BrachyVision ACUROS™) and state-of-the-art Monte Carlo (MC) codes, including ALGEBRA, BrachyDose, egs_brachy, Geant4, MCNP6, and Penelope2008. TPS-based volumetric dose distributions for the previously reported "source centered in water" and "source displaced" test cases, and the new "source centered in applicator" test case, were analyzed here using the MCNP6 dose distribution as a reference. Volumetric dose comparisons of TPS results against results for the other MC codes were also performed. Distributions of local and global dose difference ratios are reported. The local dose differences among MC codes are comparable to the statistical uncertainties of the reference datasets for the "source centered in water" and "source displaced" test

  12. Therapeutic analysis of high-dose-rate {sup 192}Ir vaginal cuff brachytherapy for endometrial cancer using a cylindrical target volume model and varied cancer cell distributions

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hualin, E-mail: hualin.zhang@northwestern.edu; Donnelly, Eric D.; Strauss, Jonathan B. [Department of Radiation Oncology, Robert H. Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Northwestern Memorial Hospital, Chicago, Illinois 60611 (United States); Qi, Yujin [Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522 (Australia)

    2016-01-15

    Purpose: To evaluate high-dose-rate (HDR) vaginal cuff brachytherapy (VCBT) in the treatment of endometrial cancer in a cylindrical target volume with either a varied or a constant cancer cell distributions using the linear quadratic (LQ) model. Methods: A Monte Carlo (MC) technique was used to calculate the 3D dose distribution of HDR VCBT over a variety of cylinder diameters and treatment lengths. A treatment planning system (TPS) was used to make plans for the various cylinder diameters, treatment lengths, and prescriptions using the clinical protocol. The dwell times obtained from the TPS were fed into MC. The LQ model was used to evaluate the therapeutic outcome of two brachytherapy regimens prescribed either at 0.5 cm depth (5.5 Gy × 4 fractions) or at the vaginal mucosal surface (8.8 Gy × 4 fractions) for the treatment of endometrial cancer. An experimentally determined endometrial cancer cell distribution, which showed a varied and resembled a half-Gaussian distribution, was used in radiobiology modeling. The equivalent uniform dose (EUD) to cancer cells was calculated for each treatment scenario. The therapeutic ratio (TR) was defined by comparing VCBT with a uniform dose radiotherapy plan in term of normal cell survival at the same level of cancer cell killing. Calculations of clinical impact were run twice assuming two different types of cancer cell density distributions in the cylindrical target volume: (1) a half-Gaussian or (2) a uniform distribution. Results: EUDs were weakly dependent on cylinder size, treatment length, and the prescription depth, but strongly dependent on the cancer cell distribution. TRs were strongly dependent on the cylinder size, treatment length, types of the cancer cell distributions, and the sensitivity of normal tissue. With a half-Gaussian distribution of cancer cells which populated at the vaginal mucosa the most, the EUDs were between 6.9 Gy × 4 and 7.8 Gy × 4, the TRs were in the range from (5.0){sup 4} to (13

  13. External-Beam Radiation Therapy and High-Dose Rate Brachytherapy Combined With Long-Term Androgen Deprivation Therapy in High and Very High Prostate Cancer: Preliminary Data on Clinical Outcome

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Monge, Rafael, E-mail: rmartinezm@unav.es [Department of Radiation Oncology, Clinica Universitaria de Navarra, University of Navarra, Pamplona, Navarre (Spain); Moreno, Marta; Ciervide, Raquel; Cambeiro, Mauricio [Department of Radiation Oncology, Clinica Universitaria de Navarra, University of Navarra, Pamplona, Navarre (Spain); Perez-Gracia, Jose Luis; Gil-Bazo, Ignacio [Department of Medical Oncology, Clinica Universitaria de Navarra, University of Navarra, Pamplona, Navarre (Spain); Gaztanaga, Miren; Arbea, Leire [Department of Radiation Oncology, Clinica Universitaria de Navarra, University of Navarra, Pamplona, Navarre (Spain); Pascual, Ignacio [Department of Urology, Clinica Universitaria de Navarra, University of Navarra, Pamplona, Navarre (Spain); Aristu, Javier [Department of Radiation Oncology, Clinica Universitaria de Navarra, University of Navarra, Pamplona, Navarre (Spain)

    2012-03-01

    Purpose: To determine the feasibility of combined long-term androgen deprivation therapy (ADT) and dose escalation with high-dose-rate (HDR) brachytherapy. Methods and Materials: Between 2001 and 2007, 200 patients with high-risk prostate cancer (32.5%) or very high-risk prostate cancer (67.5%) were prospectively enrolled in this Phase II trial. Tumor characteristics included a median pretreatment prostate-specific antigen of 15.2 ng/mL, a clinical stage of T2c, and a Gleason score of 7. Treatment consisted of 54 Gy of external irradiation (three-dimensional conformal radiotherapy [3DCRT]) followed by 19 Gy of HDR brachytherapy in four twice-daily treatments. ADT started 0-3 months before 3DCRT and continued for 2 years. Results: One hundred and ninety patients (95%) received 2 years of ADT. After a median follow-up of 3.7 years (range, 2-9), late Grade {>=}2 urinary toxicity was observed in 18% of the patients and Grade {>=}3 was observed in 5%. Prior transurethral resection of the prostate (p = 0.013) and bladder D{sub 50} {>=}1.19 Gy (p = 0.014) were associated with increased Grade {>=}2 urinary complications; age {>=}70 (p = 0.05) was associated with Grade {>=}3 urinary complications. Late Grade {>=}2 gastrointestinal toxicity was observed in 9% of the patients and Grade {>=}3 in 1.5%. CTV size {>=}35.8 cc (p = 0.007) and D{sub 100} {>=}3.05 Gy (p = 0.01) were significant for increased Grade {>=}2 complications. The 5-year and 9-year biochemical relapse-free survival (nadir + 2) rates were 85.1% and 75.7%, respectively. Patients with Gleason score of 7-10 had a decreased biochemical relapse-free survival (p = 0.007). Conclusions: Intermediate-term results at the 5-year time point indicate a favorable outcome without an increase in the rate of late complications.

  14. Dedicated high dose rate 192Ir brachytherapy radiation fields for in vitro cell exposures at variable source-target cell distances: killing of mammalian cells depends on temporal dose rate fluctuation

    Science.gov (United States)

    Veigel, Cornelia; Hartmann, Günther H.; Fritz, Peter; Debus, Jürgen; Weber, Klaus-Josef

    2017-02-01

    Afterloading brachytherapy is conducted by the stepwise movement of a radioactive source through surgically implanted applicator tubes where at predefined dwell positions calculated dwell times optimize spatial dose delivery with respect to a planned dose level. The temporal exposure pattern exhibits drastic fluctuations in dose rate at a given coordinate and within a single treatment session because of the discontinuous and repeated source movement into the target volume. This could potentially affect biological response. Therefore, mammalian cells were exposed as monolayers to a high dose rate 192Ir source by utilizing a dedicated irradiation device where the distance between a planar array of radioactive source positions and the plane of the cell monolayer could be varied from 2.5 mm to 40 mm, thus varying dose rate pattern for any chosen total dose. The Gammamed IIi afterloading system equipped with a nominal 370 GBq (10 Ci) 192-Ir source was used to irradiate V79 Chinese hamster lung fibroblasts from both confluent and from exponential growth phase with dose up to 12 Gy (at room temperature, total exposure not exceeding 1 h). For comparison, V79 cells were also exposed to 6 MV x-rays from a clinical linear accelerator (dose rate of 2.5 Gy min-1). As biological endpoint, cell survival was determined by standard colony forming assay. Dose measurements were conducted with a diamond detector (sensitive area 7.3 mm2), calibrated by means of 60Co radiation. Additionally, dose delivery was simulated by Monte Carlo calculations using the EGSnrc code system. The calculated secondary electron fluence spectra at the cell location did not indicate a significant change of radiation quality (i.e. higher linear energy transfer) at the lower distances. Clonogenic cell survival curves obtained after brachytherapy exhibited an altered biological response compared to x-rays which was characterized by a significant reduction of the survival curve shoulder when dose rate

  15. Systemic response of Korean dark-striped field mice, Apodenmus agrarius coreae after high-dose- rate γ-irradiation: Organ weights, hemato-chemistry, apoptosis of splenocytes and sperm

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Kwang Hee; Choi, Hoon; Joo, Hyun Jin; Kim, Hee Sun [Radiation Health Research Institute, KHNP, Gyeongju (Korea, Republic of); Keum, Dong Kwon [Nuclear Environment Research Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-11-15

    Since the territory of the radio-contaminated area is in homeogenous in radiation level and spectrum, investigation of the genetical mutation process in the natural animal populations inhabiting the radioontaminated areas will be provide a realistic picture of genetic effects for radiation exposure. However, little is known about the basic data such as systemic responses after ionizing radiation exposures in wild small rodents. Taking into account different radio-sensitivity of dark-striped field mice (A. a. coreae, THOMAS), the objective of the study is focus on investigate the level of systemic responses, included organ weights, hemato-chemistry and apoptosis in splenocytes and sperm of caudal epididymis after high-dose-rate irradiation especially as a potential biological dosimeter in radio-ecology. Figure 1 summarizes the results of the apoptotic events in spleen (data not shown at here) and in sperm of caudal epididymis at 24hrs after a single high-dose-rate γ-irradiation. The results of apoptosis in spleen and sperm caused by exposure to different doses of γ-irradiation are displayed. The data show that the field striped mice after irradiated with more than high dose of 0.5 Gy induces an significantly increased apoptosis. Results also shown that for exposure to 0.5 Gy, the apoptosis of both organs ware decreased compared to those of other γ-irradiated mice.

  16. Phase I Study of Concurrent High-Dose Three-Dimensional Conformal Radiotherapy With Chemotherapy Using Cisplatin and Vinorelbine for Unresectable Stage III Non-Small-Cell Lung Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Sekine, Ikuo, E-mail: isekine@ncc.go.jp [Division of Internal Medicine and Thoracic Oncology, National Cancer Center Hospital, Tokyo (Japan); Sumi, Minako; Ito, Yoshinori [Division of Radiation Oncology, National Cancer Center Hospital, Tokyo (Japan); Horinouchi, Hidehito; Nokihara, Hiroshi; Yamamoto, Noboru; Kunitoh, Hideo; Ohe, Yuichiro; Kubota, Kaoru; Tamura, Tomohide [Division of Internal Medicine and Thoracic Oncology, National Cancer Center Hospital, Tokyo (Japan)

    2012-02-01

    Purpose: To determine the maximum tolerated dose in concurrent three-dimensional conformal radiotherapy (3D-CRT) with chemotherapy for unresectable Stage III non-small-cell lung cancer (NSCLC). Patients and Methods: Eligible patients with unresectable Stage III NSCLC, age {>=}20 years, performance status 0-1, percent of volume of normal lung receiving 20 GY or more (V{sub 20}) {<=}30% received three to four cycles of cisplatin (80 mg/m{sup 2} Day 1) and vinorelbine (20 mg/m{sup 2} Days 1 and 8) repeated every 4 weeks. The doses of 3D-CRT were 66 Gy, 72 Gy, and 78 Gy at dose levels 1 to 3, respectively. Results: Of the 17, 16, and 24 patients assessed for eligibility, 13 (76%), 12 (75%), and 6 (25%) were enrolled at dose levels 1 to 3, respectively. The main reasons for exclusion were V{sub 20} >30% (n = 10) and overdose to the esophagus (n = 8) and brachial plexus (n = 2). There were 26 men and 5 women, with a median age of 60 years (range, 41-75). The full planned dose of radiotherapy could be administered to all the patients. Grade 3-4 neutropenia and febrile neutropenia were noted in 24 (77%) and 5 (16%) of the 31 patients, respectively. Grade 4 infection, Grade 3 esophagitis, and Grade 3 pulmonary toxicity were noted in 1 patient, 2 patients, and 1 patient, respectively. The dose-limiting toxicity was noted in 17% of the patients at each dose level. The median survival and 3-year and 4-year survival rates were 41.9 months, 72.3%, and 49.2%, respectively. Conclusions: 72 Gy was the maximum dose that could be achieved in most patients, given the predetermined normal tissue constraints.

  17. Bladder accumulated dose in image-guided high-dose-rate brachytherapy for locally advanced cervical cancer and its relation to urinary toxicity

    Science.gov (United States)

    Zakariaee, Roja; Hamarneh, Ghassan; Brown, Colin J.; Gaudet, Marc; Aquino-Parsons, Christina; Spadinger, Ingrid

    2016-12-01

    The purpose of this study was to estimate locally accumulated dose to the bladder in multi-fraction high-dose-date (HDR) image-guided intracavitary brachytherapy (IG-ICBT) for cervical cancer, and study the locally-accumulated dose parameters as predictors of late urinary toxicity. A retrospective study of 60 cervical cancer patients who received five HDR IG-ICBT sessions was performed. The bladder outer and inner surfaces were segmented for all sessions and a bladder-wall contour point-set was created in MATLAB. The bladder-wall point-sets for each patient were registered using a deformable point-set registration toolbox called coherent point drift (CPD), and the fraction doses were accumulated. Various dosimetric and volumetric parameters were calculated using the registered doses, including r{{\\text{D}}n \\text{c{{\\text{m}}\\text{3}}}} (minimum dose to the most exposed n-cm3 volume of bladder wall), r V n Gy (wall volume receiving at least m Gy), and r\\text{EQD}{{2}n \\text{c{{\\text{m}}\\text{3}}}} (minimum equivalent biologically weighted dose to the most exposed n-cm3 of bladder wall), where n  =  1/2/5/10 and m  =  3/5/10. Minimum dose to contiguous 1 and 2 cm3 hot-spot volumes was also calculated. The unregistered dose volume histogram (DVH)-summed equivalent of r{{\\text{D}}n \\text{c{{\\text{m}}3}}} and r\\text{EQD}{{2}n \\text{c{{\\text{m}}3}}} parameters (i.e. s{{\\text{D}}n \\text{c{{\\text{m}}\\text{3}}}} and s\\text{EQD}{{2}n \\text{c{{\\text{m}}3}}} ) were determined for comparison. Late urinary toxicity was assessed using the LENT-SOMA scale, with toxicity Grade 0-1 categorized as Controls and Grade 2-4 as Cases. A two-sample t-test was used to identify the differences between the means of Control and Case groups for all parameters. A binomial logistic regression was also performed between the registered dose parameters and toxicity grouping. Seventeen patients were in the Case and 43 patients in the Control group. Contiguous

  18. Routine High Dose Excretory Urography

    Science.gov (United States)

    Gronner, Arthur T.; Arkoff, Robert S.; Burhenne, H. Joachim

    1967-01-01

    Radiologic evaluation of 316 excretory urograms utilizing a single 50 ml injection of a 50 to 60 per cent tri-iodinated contrast medium indicated that these studies are of better quality than those previously obtained with the injection of 30 ml. The low incidence of side effects coincides with recent reports in the literature that this dosage level is safe. High dose intravenous drip infusion pyelography was necessary only in selected cases. High dose excretory urography is recommended for routine use. ImagesFigure 1A, 1BFigure 2. PMID:6045483

  19. Evaluation of failure modes of computerized planning phase of interstitial implants with high dose rate brachytherapy using HFMEA; Avaliacao dos modos de falha do planejamento computadorizado em implantes intersticiais com braquiterapia de alta taxa de dose usando HFMEA

    Energy Technology Data Exchange (ETDEWEB)

    Biazotto, Bruna; Tokarski, Marcio, E-mail: bruna@ceb.unicamp.br [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Centro de Engenharia Biomedica

    2014-08-15

    This paper evaluates the failure modes of the computerized planning step in interstitial implants with high dose rate brachytherapy. The prospective tool of risk management Health Care Failure Mode and Effects Analysis (HFMEA) was used. Twelve subprocesses were identified, and 33 failure modes of which 21 justified new safety actions, and 9 of them were intolerable risks. The method proved itself useful in identifying failure modes, but laborious and subjective in their assessment. The main risks were due to human factors, which require training and commitment of management to their mitigation. (author)

  20. Verification of the calculation program for brachytherapy planning system of high dose rate (PLATO); Programa de verificacion del calculo para un sistema de planificacion de braquiterapia de alta tasa de dosis (PLATO)

    Energy Technology Data Exchange (ETDEWEB)

    Almansa, J.; Alaman, C.; Perez-Alija, J.; Herrero, C.; Real, R. del; Ososrio, J. L.

    2011-07-01

    In our treatments are performed brachytherapy high dose rate since 2007. The procedures performed include gynecological intracavitary treatment and interstitial. The treatments are performed with a source of Ir-192 activity between 5 and 10 Ci such that small variations in treatment times can cause damage to the patient. In addition the Royal Decree 1566/1998 on Quality Criteria in radiotherapy establishes the need to verify the monitor units or treatment time in radiotherapy and brachytherapy. All this justifies the existence of a redundant system for brachytherapy dose calculation that can reveal any abnormality is present.

  1. Rectal Bleeding After High-Dose-Rate Brachytherapy Combined With Hypofractionated External-Beam Radiotherapy for Localized Prostate Cancer: The Relationship Between Dose-Volume Histogram Parameters and the Occurrence Rate

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, Masahiko, E-mail: masaoka@showa.gunma-u.ac.jp [Department of Radiation Oncology, Gunma University Graduate School of Medicine, Gunma (Japan); Ishikawa, Hitoshi; Ebara, Takeshi; Kato, Hiroyuki; Tamaki, Tomoaki [Department of Radiation Oncology, Gunma University Graduate School of Medicine, Gunma (Japan); Akimoto, Tetsuo [Department of Radiation Oncology, Tokyo Women' s Medical University, Tokyo (Japan); Ito, Kazuto; Miyakubo, Mai; Yamamoto, Takumi; Suzuki, Kazuhiro [Department of Urology, Gunma University Graduate School of Medicine, Gunma (Japan); Takahashi, Takeo; Nakano, Takashi [Department of Radiation Oncology, Gunma University Graduate School of Medicine, Gunma (Japan)

    2012-02-01

    Purpose: To determine the predictive risk factors for Grade 2 or worse rectal bleeding after high-dose-rate brachytherapy (HDR-BT) combined with hypofractionated external-beam radiotherapy (EBRT) for prostate cancer using dose-volume histogram analysis. Methods and Materials: The records of 216 patients treated with HDR-BT combined with EBRT were analyzed. The treatment protocols for HDR-BT were 5 Gy Multiplication-Sign five times in 3 days or 7 Gy Multiplication-Sign three, 10.5 Gy Multiplication-Sign two, or 9 Gy Multiplication-Sign two in 2 days. The EBRT doses ranged from 45 to 51 Gy with a fractional dose of 3 Gy. Results: In 20 patients Grade 2 or worse rectal bleeding developed, and the cumulative incidence rate was 9% at 5 years. By converting the HDR-BT and EBRT radiation doses into biologic effective doses (BED), the BED{sub 3} at rectal volumes of 5% and 10% in the patients who experienced bleeding were significantly higher than those in the remaining 196 patients. Univariate analysis showed that a higher rectal BED{sub 3-5%} and the use of fewer needles in brachytherapy were correlated with the incidence of bleeding, but BED{sub 3-5%} was found to be the only significant factor on multivariate analysis. Conclusions: The radiation dose delivered to small rectal lesions as 5% is important for predicting Grade 2 or worse rectal bleeding after HDR-BT combined with EBRT for prostate cancer.

  2. Dose-volume analysis of target volume and critical structures in computed tomography image-based multicatheter high-dose-rate interstitial brachytherapy for head and neck cancer

    Directory of Open Access Journals (Sweden)

    Hironori Akiyama

    2017-12-01

    Full Text Available Purpose : To evaluate dose-volume relationships of target volume and critical structures in computed tomography (CT image-based brachytherapy for head and neck cancer. Material and methods : Thirty-seven patients with mobile tongue, floor of mouth, and base of tongue cancer treated with brachytherapy (post-operative alone and as a boost after external beam radiotherapy [EBRT], or definitive alone or as a boost after EBRT were selected. Treatment plans were made using post-implant CT images. The fractionation schedule was 7-15 × 3-5 Gy for post-operative (with or without EBRT, 14-15 × 3 Gy for definitive alone, and 5-10 × 3 Gy for boost treatments. For the target volume, V 100 , D 90 , and dose non-uniformity ratio (DNR were calculated. For the mandible, spinal cord and salivary glands doses to specified volumes were reported. Results : The median values of V 100 and D 90 were 89.9% and 99.9%, respectively; the median values of DNR was 0.46. The median D 2cm 3 of the mandible and spinal cord were 48.3% and 5.8%, respectively. The ipsilateral median D 2cm 3 of parotid and submandibular glands were 6.4% and 12.5%, whereas on the contralateral side, the corresponding values were 5.3% and 7.0%, respectively. Conclusions : Using conformal treatment planning, it was desirable to keep the dose to the mandible, spinal cord, and salivary glands at an acceptable level. The quantitative plan evaluation may help us find correlations between dosimetric parameters and clinical outcome, which may lead to improve the quality of the treatment, but it requires longer follow-up and results from other studies.

  3. Fluzone High-Dose Seasonal Influenza Vaccine

    Science.gov (United States)

    ... Variant Pandemic Other Fluzone High-Dose Seasonal Influenza Vaccine Questions & Answers Language: English (US) Español Recommend on ... flu season. What is Fluzone High-Dose influenza vaccine? Fluzone High-Dose is an influenza vaccine, manufactured ...

  4. Effects of High-Dose α-Lipoic Acid on Heart Rate Variability of Type 2 Diabetes Mellitus Patients with Cardiac Autonomic Neuropathy in Korea.

    Science.gov (United States)

    Lee, Sol Jae; Jeong, Su Jin; Lee, Yu Chang; Lee, Yong Hoon; Lee, Jung Eun; Kim, Chong Hwa; Min, Kyung Wan; Cha, Bong Yun

    2017-08-01

    Diabetic cardiac autonomic neuropathy (CAN) is one of the important complications of diabetes. It is characterized by reduced heart rate variability (HRV). In this randomized, double-blind, placebo-controlled, multicenter trial, 75 patients were randomly assigned to one of two groups. One group (n=41) received α-lipoic acid (ALA) at an oral dose of 600 mg/day for the first 12 weeks and then 1,200 mg/day for the next 12 weeks. The other group (n=34) received placebo treatment for 24 weeks. CAN was assessed by measuring HRVs in people with diabetes. Most of the baseline measures for HRVs were similar between the ALA and placebo groups. Although there were no statistically significant HRV changes in the ALA group compared to the placebo group after 24 weeks of trial, we found a positive tendency in some of the HRV parameters of the ALA group. The standard deviations of normal-to-normal RR intervals in the standing position increased by 1.87 ms in the ALA group but decreased by -3.97 ms in the placebo group (P=0.06). The power spectrum of the low frequency (LF) band in the standing position increased by 15.77 ms² in the ALA group, whereas it declined by -15.04 ms² in the placebo group (P=0.08). The high frequency/LF ratio in the upright position increased by 0.35 in the ALA group, whereas it declined by -0.42 in the placebo group (P=0.06). There were no differences between the two groups regarding rates of adverse events. Although a slight improvement tendency was seen in HRV in the ALA group, there were no statistically significant HRV changes in the ALA group compared to the placebo group after 24 weeks of trial. However, the high oral dose of ALA was well-tolerated.

  5. A comparison of the biological effects of 125I seeds continuous low-dose-rate radiation and 60Co high-dose-rate gamma radiation on non-small cell lung cancer cells.

    Directory of Open Access Journals (Sweden)

    Zhongmin Wang

    Full Text Available To compare the biological effects of 125I seeds continuous low-dose-rate (CLDR radiation and 60Co γ-ray high-dose-rate (HDR radiation on non-small cell lung cancer (NSCLC cells.A549, H1299 and BEAS-2B cells were exposed to 125I seeds CLDR radiation or 60Co γ-ray HDR radiation. The survival fraction was determined using a colony-forming assay. The cell cycle progression and apoptosis were detected by flow cytometry (FCM. The expression of the apoptosis-related proteins caspase-3, cleaved-caspase-3, PARP, cleaved-PARP, BAX and Bcl-2 were detected by western blot assay.After irradiation with 125I seeds CLDR radiation, there was a lower survival fraction, more pronounced cell cycle arrest (G1 arrest and G2/M arrest in A549 and H1299 cells, respectively and a higher apoptotic ratio for A549 and H1299 cells than after 60Co γ-ray HDR radiation. Moreover, western blot assays revealed that 125I seeds CLDR radiation remarkably up-regulated the expression of Bax, cleaved-caspase-3 and cleaved-PARP proteins and down-regulated the expression of Bcl-2 proteins in A549 and H1299 cells compared with 60Co γ-ray HDR radiation. However, there was little change in the apoptotic ratio and expression of apoptosis-related proteins in normal BEAS-2B cells receiving the same treatment.125I seeds CLDR radiation led to remarkable growth inhibition of A549 and H1299 cells compared with 60Co HDR γ-ray radiation; A549 cells were the most sensitive to radiation, followed by H1299 cells. In contrast, normal BEAS-2B cells were relatively radio-resistant. The imbalance of the Bcl-2/Bax ratio and the activation of caspase-3 and PARP proteins might play a key role in the anti-proliferative effects induced by 125I seeds CLDR radiation, although other possibilities have not been excluded and will be investigated in future studies.

  6. SU-F-T-506: Development and Commissioning of the Effective and Efficient Grid Therapy Using High Dose Rate Flattening Filter Free Beam and Multileaf Collimator

    Energy Technology Data Exchange (ETDEWEB)

    Liu, M; Wen, N; Beyer, C; Siddiqui, F; Chetty, I; Zhao, B [Henry Ford Health System, Detroit, MI (United States)

    2016-06-15

    Purpose: Treating bulky tumors with grid therapy (GT) has demonstrated high response rates. Long delivery time (∼15min), with consequent increased risk of intrafraction motion, is a major disadvantage of conventional MLC-based GT (MLC-GT). The goal of this study was to develop and commission a MLC-GT technique with similar dosimetric characteristics, but more efficient delivery. Methods: Grid plan was designed with 10X-FFF (2400MU/min) beam and MLC in a commercial treatment planning system (TPS). Grid size was 1cm by 1cm and grid-to-grid distance was 2cm. Field-in-field technique was used to flatten the dose profile at depth of 10cm. Prescription was 15Gy at 1.5cm depth. Doses were verified at depths of 1.5cm, 5cm and 10cm. Point dose was measured with a plastic scintillator detector (PSD) while the planar dose was measured with calibrated Gafchromic EBT3 films in a 20cm think, 30cmx30cm solid water phantom. The measured doses were compared to the doses calculated in the treatment planning system. Percent depth dose (PDD) within the grid was also measured using EBT3 film. Five clinical cases were planned to compare beam-on time. Results: The valley-to-peak dose ratio at the 3 depths was approximately 10–15%, which is very similar to published result. The average point dose difference between the PSD measurements and TPS calculation is 2.1±0.6%. Film dosimetry revealed good agreement between the delivered and calculated dose. The average gamma passing rates at the 3 depths were 95% (3%, 1mm). The average percent difference between the measured PDD and calculated PDD was 2.1% within the depth of 20cm. The phantom plan delivery time was 3.6 min. Average beam-on time was reduced by 66.1±5.6% for the 5 clinical cases. Conclusion: An effective and efficient GT technique was developed and commissioned for the treatment of bulky tumors using FFF beam combined with MLC and automation. The Department of Radiation Oncology at Henry Ford Health System receives research

  7. Commissioning of applicator-guided stereotactic body radiation therapy boost with high-dose-rate brachytherapy for advanced cervical cancer using radiochromic film dosimetry.

    Science.gov (United States)

    Aldelaijan, Saad; Wadi-Ramahi, Shada; Nobah, Ahmad; Moftah, Belal; Devic, Slobodan; Jastaniyah, Noha

    To describe an EBT3 GAFCHROMIC film-based dosimetry method to be used in commissioning of a combined HDR brachytherapy (HDRB) and stereotactic body radiation therapy (SBRT) boost for treatment of advanced cervical cancer involving extensive residual disease after external beam treatment. A cube phantom was designed to firmly fit an intrauterine tandem applicator and EBT3 radiochromic film pieces. A high-risk clinical target volume (CTVHR, Total) was contoured with an extended arm at one side. The HDRB treatment was planned to cover the proximal CTVHR, Total with 7 Gy and the distal volume, referred to as CTVHR, Distal, was planned by SBRT for dose augmentation. After HDRB treatment delivery, SBRT treatment was delivered within 1 hour by image guidance using the applicator geometry. Intentional 1D and 2D misalignments were introduced to evaluate the effect on target volumes. In addition, effect of film reirradiation at different time gaps and dose levels was evaluated. Film dosimetric accuracy, with up to 2 hours gap between irradiations, was shown to be unaffected. A 2%/2 mm gamma analysis between measured and planned doses showed agreement of >99%. Misalignments of more than 2 mm between applicator and SBRT isocenter resulted in suboptimal dose-volume histogram affecting mostly D98% and D90% of CTVHR, Distal. Visualizing how target dose-volume metrics are affected by minor misalignments between SBRT and HDRB dose gradients, in light of achievable phantom-based experimental quality assurance level, encourages the clinical applicability of this technique. Radiochromic film was shown to be a valuable tool to commission procedures combining two different treatment planning systems and modalities with varying dose rates and energy ranges. Copyright © 2017 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  8. High dose rate brachytherapy in the treatment of endometrium carcinoma; Tratamento de cancer do endometrio com braquiterapia de alta taxa de dose

    Energy Technology Data Exchange (ETDEWEB)

    Aisen, Salim; Carvalho, Heloisa A.; Nadalin, Wladimir [Sao Paulo Univ., SP (Brazil). Hospital das Clinicas. Servico de Radioterapia

    1995-11-01

    One hundred and four patients with histologic proven carcinoma of the endometrium were referred to our department for treatment. The median age was 65.5 years and the median follow-up was 38 months. Ninety-five was pos-menopaused, 7 peri and 2 were pre-menopaused. Sixteen patients were staged (pos-surgery) IA, 5 GI, 8 G2 and 3 G3. Thirty and four stage IB, 10 G1, 18 G2 and 1 G3. Twenty-five were stage IC, 9 G1, 9 G2 and 7 G3. Six were stage IIA, 2 GI, 3 G2 and 1 G3. Eight were stages IIB, 1 G1,3 G2 and 4 G3. Nine were stage IIA, 2 GI, 5 G2, 2 G3. Three were stage IIIB, 2 GI and 1 G2. One was stage III C G3, and two were IVA G3. Depending of the extension of the disease, patients underwent total hysterectomy and bilateral salpino-ooforectomy, or total hysterectomy and bilateral salpino-ooforectomy plus omentectomy or Werthein-Megs technique. All the patients IA and IB have no evidence of disease (NED). Twenty-four patients IC are NED and one presented distant metastasis. From the IIB patients, 6 are NED, one shown progressive local disease (PLD) and one died from disease. From the patients IIIA, 7 are NED, one DM and one PLD. From the IIIB patients one is NED and TWO are PLD. From the IIIC patient is NED two months after treatment and the IVA patients are NED three and four month after treatment. Eight patients have shown mild complications of treatment. The results of survival and complications are similar to the therapeutic with low dose rate brachytherapy, with the advantage of an outpatient treatment, without the inconvenience of impatient regime. (author). 22 refs., 1 tab.

  9. SU-F-P-39: End-To-End Validation of a 6 MV High Dose Rate Photon Beam, Configured for Eclipse AAA Algorithm Using Golden Beam Data, for SBRT Treatments Using RapidArc

    Energy Technology Data Exchange (ETDEWEB)

    Ferreyra, M; Salinas Aranda, F; Dodat, D; Sansogne, R; Arbiser, S [Vidt Centro Medico, Ciudad Autonoma De Buenos Aires, Ciudad Autonoma de Buenos Aire (Argentina)

    2016-06-15

    Purpose: To use end-to-end testing to validate a 6 MV high dose rate photon beam, configured for Eclipse AAA algorithm using Golden Beam Data (GBD), for SBRT treatments using RapidArc. Methods: Beam data was configured for Varian Eclipse AAA algorithm using the GBD provided by the vendor. Transverse and diagonals dose profiles, PDDs and output factors down to a field size of 2×2 cm2 were measured on a Varian Trilogy Linac and compared with GBD library using 2% 2mm 1D gamma analysis. The MLC transmission factor and dosimetric leaf gap were determined to characterize the MLC in Eclipse. Mechanical and dosimetric tests were performed combining different gantry rotation speeds, dose rates and leaf speeds to evaluate the delivery system performance according to VMAT accuracy requirements. An end-to-end test was implemented planning several SBRT RapidArc treatments on a CIRS 002LFC IMRT Thorax Phantom. The CT scanner calibration curve was acquired and loaded in Eclipse. PTW 31013 ionization chamber was used with Keithley 35617EBS electrometer for absolute point dose measurements in water and lung equivalent inserts. TPS calculated planar dose distributions were compared to those measured using EPID and MapCheck, as an independent verification method. Results were evaluated with gamma criteria of 2% dose difference and 2mm DTA for 95% of points. Results: GBD set vs. measured data passed 2% 2mm 1D gamma analysis even for small fields. Machine performance tests show results are independent of machine delivery configuration, as expected. Absolute point dosimetry comparison resulted within 4% for the worst case scenario in lung. Over 97% of the points evaluated in dose distributions passed gamma index analysis. Conclusion: Eclipse AAA algorithm configuration of the 6 MV high dose rate photon beam using GBD proved efficient. End-to-end test dose calculation results indicate it can be used clinically for SBRT using RapidArc.

  10. Concomitant chemoradiotherapy with high dose rate brachytherapy ...

    African Journals Online (AJOL)

    Tamer Refaat

    2011-06-12

    Jun 12, 2011 ... The mean age was 48.49 years. EBR to the whole pelvis TO 45 Gy in 25 fractions .... with radio-opaque seeds or a radio-opaque vaginal tampon. Barium or another radio-opaque device was used to ..... A common language has been developed that allows differ- ent BT traditions to communicate. Important ...

  11. Computed tomography-based treatment planning for high-dose-rate brachytherapy using the tandem and ring applicator: influence of applicator choice on organ dose and inter-fraction adaptive planning

    Directory of Open Access Journals (Sweden)

    Vishruta A. Dumane

    2017-06-01

    Full Text Available Three dimensional planning for high-dose-rate (HDR brachytherapy in cervical cancer has been highly recommended by consensus guidelines such as the American Brachytherapy Society (ABS and the Groupe Européen de Curiethérapie – European Society for Radiotherapy and Oncology (GEC-ESTRO. In this document, we describe our experience with computed tomography (CT-based planning using the tandem/ring applicator. We discuss the influence of applicator geometry on doses to organs at risk (OARs, namely the bladder, rectum, and sigmoid. Through example cases with dose prescribed to point A, we demonstrate how adaptive planning can help achieve constraints to the OARs as per guidelines.

  12. Objective and Longitudinal Assessment of Dermatitis After Postoperative Accelerated Partial Breast Irradiation Using High-Dose-Rate Interstitial Brachytherapy in Patients With Breast Cancer Treated With Breast Conserving Therapy: Reduction of Moisture Deterioration by APBI

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Eiichi [Department of Radiation Oncology, National Hospital Organization, Osaka National Hospital, Osaka (Japan); Yamazaki, Hideya, E-mail: hideya10@hotmail.com [Department of Radiology, Kyoto Prefectural University of Medicine, Kyoto (Japan); Yoshida, Ken; Takenaka, Tadashi [Department of Radiation Oncology, National Hospital Organization, Osaka National Hospital, Osaka (Japan); Masuda, Norikazu [Department of Surgery and Breast Oncology, National Hospital Organization, Osaka National Hospital, Osaka (Japan); Kotsuma, Tadayuki; Yoshioka, Yasuo; Inoue, Takehiro [Department of Radiation Oncology, Osaka University Graduate School of Medicine, Suita (Japan)

    2011-11-15

    Purpose: To objectively evaluate the radiation dermatitis caused by accelerated partial breast irradiation (APBI) using high-dose-rate interstitial brachytherapy. Patients and Methods: The skin color and moisture changes were examined using a newly installed spectrophotometer and corneometer in 22 patients who had undergone APBI using open cavity implant high-dose-rate interstitial brachytherapy (36 Gy in six fractions) and compared with the corresponding values for 44 patients in an external beam radiotherapy (EBRT) control group (50-60 Gy in 25-30 fractions within 5-6 weeks) after breast conserving surgery. Results: All values changed significantly as a result of APBI. The extent of elevation in a Asterisk-Operator (reddish) and reduction in L Asterisk-Operator (black) values caused by APBI were similar to those for EBRT, with slightly delayed recovery for 6-12 months after treatment owing to the surgical procedure. In contrast, only APBI caused a change in the b Asterisk-Operator values, and EBRT did not, demonstrating that the reduction in b Asterisk-Operator values (yellowish) depends largely on the surgical procedure. The changes in moisture were less severe after APBI than after EBRT, and the recovery was more rapid. The toxicity assessment using the Common Toxicity Criteria, version 3, showed that all dermatitis caused by APBI was Grade 2 or less. Conclusion: An objective analysis can quantify the effects of APBI procedures on color and moisture cosmesis. The radiation dermatitis caused by APBI using the present schedule showed an equivalent effect on skin color and a less severe effect on moisture than the effects caused by standard EBRT.

  13. Determinants of Toxicity, Patterns of Failure, and Outcome Among Adult Patients With Soft Tissue Sarcomas of the Extremity and Superficial Trunk Treated With Greater Than Conventional Doses of Perioperative High-Dose-Rate Brachytherapy and External Beam Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    San Miguel, Inigo [Department of Radiation Oncology, Clinica Universidad de Navarra, University of Navarra, Navarre (Spain); San Julian, Mikel [Department of Orthopedic Surgery, Clinica Universidad de Navarra, University of Navarra, Navarre (Spain); Cambeiro, Mauricio [Department of Radiation Oncology, Clinica Universidad de Navarra, University of Navarra, Navarre (Spain); Sanmamed, Miguel Fernandez [Department of Medical Oncology, Clinica Universidad de Navarra, University of Navarra, Navarre (Spain); Vazquez-Garcia, Blanca [Department of Orthopedic Surgery, Clinica Universidad de Navarra, University of Navarra, Navarre (Spain); Pagola, Maria; Gaztanaga, Miren [Department of Radiation Oncology, Clinica Universidad de Navarra, University of Navarra, Navarre (Spain); Martin-Algarra, Salvador [Department of Medical Oncology, Clinica Universidad de Navarra, University of Navarra, Navarre (Spain); Martinez-Monge, Rafael, E-mail: rmartinezm@unav.es [Department of Radiation Oncology, Clinica Universidad de Navarra, University of Navarra, Navarre (Spain)

    2011-11-15

    Purpose: The present study was undertaken to determine factors predictive of toxicity, patterns of failure, and survival in 60 adult patients with soft tissue sarcomas of the extremity and superficial trunk treated with combined perioperative high-dose-rate brachytherapy and external beam radiotherapy. Methods and Materials: The patients were treated with surgical resection and perioperative high-dose-rate brachytherapy (16 or 24 Gy) for negative and close/microscopically positive resection margins, respectively. External beam radiotherapy (45 Gy) was added postoperatively to reach a 2-Gy equivalent dose of 62.9 and 72.3 Gy, respectively. Adjuvant chemotherapy with ifosfamide and doxorubicin was given to patients with advanced high-grade tumors. Results: Grade 3 toxic events were observed in 18 patients (30%) and Grade 4 events in 6 patients (10%). No Grade 5 events were observed. A location in the lower limb was significant for Grade 3 or greater toxic events on multivariate analysis (p = .013), and the tissue volume encompassed by the 150% isodose line showed a trend toward statistical significance (p = .086). The local control, locoregional control, and distant control rate at 9 years was 77.4%, 69.5%, and 63.8%, respectively. On multivariate analysis, microscopically involved margins correlated with local control (p = .036) and locoregional control (p = .007) and tumor size correlated with distant metastases (p = .004). The 9-year disease-free survival and overall survival rate was 47.0% and 61.5%, respectively. Multivariate analysis showed poorer disease-free survival rates for patients with tumors >6 cm (p = .005) and microscopically involved margins (p = .043), and overall survival rates decreased with increasing tumor size (p = .011). Conclusions: Grade 3 or greater wound complications can probably be decreased using meticulous treatment planning to decrease the tissue volume encompassed by the 150% isodose line, especially in lower limb locations

  14. Accelerated Irradiations for High Dose Microstructures in Fast Reactor Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Jiao, Zhijie [Univ. of Michigan, Ann Arbor, MI (United States)

    2017-03-31

    The objective of this project is to determine the extent to which high dose rate, self-ion irradiation can be used as an accelerated irradiation tool to understand microstructure evolution at high doses and temperatures relevant to advanced fast reactors. We will accomplish the goal by evaluating phase stability and swelling of F-M alloys relevant to SFR systems at very high dose by combining experiment and modeling in an effort to obtain a quantitative description of the processes at high and low damage rates.

  15. High dose irradiation with hyperfractionation

    Energy Technology Data Exchange (ETDEWEB)

    Asakura, Hideo; Kurashima, Shoji; Hasegawa, Maki; Akiyama, Kazuo (Sagamihara National Hospital, Kanagawa (Japan))

    1990-10-01

    From March 1988 to January 1990, 12 patients including 7 primary lung cancers, 2 lung metastases of colorectal cancer, and each 1 gall bladder cancer, ovarian cancer, and spinal cord metastasis of prostatic cancer, received {sup 60}Co-irradiation with high dose by hyperfractionation. This hyperfractionation consisted of 1.2 Gy per fraction, twice a day with 6 hour interval, and 5 days (10 fractions) a week. The total dose administered was 81.6{approx}100 Gy. The acute reaction of skin, lung, and intestines was tolerable, and it seemed that the late damage of normal tissues was slighter and the treatment result was favorable in comparison with the conventional fractionation, but this estimation was not definite because of short observation period. It was discussed that further reduction of dose per fraction (1 Gy or below) and more increased total dose (100 Gy or more) would be promising in hyperfractionation. (author).

  16. Pulmonary Toxicity in Stage III Non-Small Cell Lung Cancer Patients Treated With High-Dose (74 Gy) 3-Dimensional Conformal Thoracic Radiotherapy and Concurrent Chemotherapy Following Induction Chemotherapy: A Secondary Analysis of Cancer and Leukemia Group B (CALGB) Trial 30105

    Energy Technology Data Exchange (ETDEWEB)

    Salama, Joseph K., E-mail: joseph.salama@duke.edu [Duke University Medical Center, Durham, NC (United States); Stinchcombe, Thomas E. [University of North Carolina at Chapel Hill, Chapel Hill, NC (United States); Gu Lin; Wang Xiaofei [CALGB Statistical Center, Duke University Medical Center, Durham, NC (United States); Morano, Karen [Quality Assurance Review Center, Lincoln, RI (United States); Bogart, Jeffrey A. [State University of New York Upstate Medical University, Syracuse, NY (United States); Crawford, Jeffrey C. [Duke University Medical Center, Durham, NC (United States); Socinski, Mark A. [University of North Carolina at Chapel Hill, Chapel Hill, NC (United States); Blackstock, A. William [Wake Forest University School of Medicine, Winston-Salem, NC (United States); Vokes, Everett E. [University of Chicago, Chicago, IL (United States)

    2011-11-15

    Purpose: Cancer and Leukemia Group B (CALGB) 30105 tested two different concurrent chemoradiotherapy platforms with high-dose (74 Gy) three-dimensional conformal radiotherapy (3D-CRT) after two cycles of induction chemotherapy for Stage IIIA/IIIB non-small cell lung cancer (NSCLC) patients to determine if either could achieve a primary endpoint of >18-month median survival. Final results of 30105 demonstrated that induction carboplatin and gemcitabine and concurrent gemcitabine 3D-CRT was not feasible because of treatment-related toxicity. However, induction and concurrent carboplatin/paclitaxel with 74 Gy 3D-CRT had a median survival of 24 months, and is the basis for the experimental arm in CALGB 30610/RTOG 0617/N0628. We conducted a secondary analysis of all patients to determine predictors of treatment-related pulmonary toxicity. Methods and Materials: Patient, tumor, and treatment-related variables were analyzed to determine their relation with treatment-related pulmonary toxicity. Results: Older age, higher N stage, larger planning target volume (PTV)1, smaller total lung volume/PTV1 ratio, larger V20, and larger mean lung dose were associated with increasing pulmonary toxicity on univariate analysis. Multivariate analysis confirmed that V20 and nodal stage as well as treatment with concurrent gemcitabine were associated with treatment-related toxicity. A high-risk group comprising patients with N3 disease and V20 >38% was associated with 80% of Grades 3-5 pulmonary toxicity cases. Conclusions: Elevated V20 and N3 disease status are important predictors of treatment related pulmonary toxicity in patients treated with high-dose 3D-CRT and concurrent chemotherapy. Further studies may use these metrics in considering patients for these treatments.

  17. Trends in high-dose opioid prescribing in Canada.

    Science.gov (United States)

    Gomes, Tara; Mamdani, Muhammad M; Paterson, J Michael; Dhalla, Irfan A; Juurlink, David N

    2014-09-01

    To describe trends in rates of prescribing of high-dose opioid formulations and variations in opioid product selection across Canada. Population-based, cross-sectional study. Canada. Retail pharmacies dispensing opioids between January 1, 2006, and December 31, 2011. Opioid dispensing rates, reported as the number of units dispensed per 1000 population, stratified by province and opioid type. The rate of dispensing high-dose opioid formulations increased 23.0%, from 781 units per 1000 population in 2006 to 961 units per 1000 population in 2011. Although these rates remained relatively stable in Alberta (6.3% increase) and British Columbia (8.4% increase), rates in Newfoundland and Labrador (84.7% increase) and Saskatchewan (54.0% increase) rose substantially. Ontario exhibited the highest annual rate of high-dose oxycodone and fentanyl dispensing (756 tablets and 112 patches per 1000 population, respectively), while Alberta's rate of high-dose morphine dispensing was the highest in Canada (347 units per 1000 population). Two of the highest rates of high-dose hydromorphone dispensing were found in Saskatchewan and Nova Scotia (258 and 369 units per 1000 population, respectively). Conversely, Quebec had the lowest rate of high-dose oxycodone and morphine dispensing (98 and 53 units per 1000 population, respectively). We found marked interprovincial variation in the dispensing of high-dose opioid formulations in Canada, emphasizing the need to understand the reasons for these differences, and to consider developing a national strategy to address opioid prescribing. Copyright© the College of Family Physicians of Canada.

  18. The relationship between the biochemical control outcomes and the quality of planning of high-dose rate brachytherapy as a boost to external beam radiotherapy for locally and locally advanced prostate cancer using the RTOG-ASTRO Phoenix definition.

    Science.gov (United States)

    Pellizzon, Antonio Cassio Assis; Salvajoli, João; Novaes, Paulo; Maia, Maria; Fogaroli, Ricardo; Gides, Doglas; Horriot, Rodrigues

    2008-06-04

    To evaluated prognostic factors and impact of the quality of planning of high dose rate brachytherapy (HDR-BT) for patients with local or locally advanced prostate cancer treated with external beam radiotherapy (EBRT) and HDR-BT. Between 1997 and 2005, 209 patients with biopsy proven prostate adenocarcinoma were treated with localized EBRT and HDR-BT at the Department of Radiation-Oncology, Hospital A. C. Camargo, Sao Paulo, Brazil. Patient's age, Gleason score (GS), clinical stage (CS), initial PSA (iPSA), risk group for biochemical failure (GR), doses of EBRT and HDR-BT, use of three-dimensional planning for HDR-BT (3DHDR) and the Biological Effective Dose (BED) were evaluated as prognostic factors for biochemical control (bC). Median age and median follow-up time were 68 and 5.3 years, respectively. Median EBRT and HDR-BT doses were 45 Gy and 20 Gy. The crude bC at 3.3 year was 94.2%. For the Low, intermediate and high risk patients the bC rates at 3.3 years were 91.5%, 90.2% and 88.5%, respectively. Overall survival (OS) and disease specific survival rates at 3.3 years were 97.8% and 98.4%, respectively. On univariate analysis the prognostic factors related bC were GR (p= 0.040), GS or = 20 Gy (p or = 99 Gy(1.5) (p or = 185 (p or = 20 Gy (p=0.008) and 3DHDR (p<0.001). we observed that the bC rates correlates with the generally accepted risk factors described in the literature. Dose escalation, evaluated through the BED, and the quality of planning of HDR-BT are also important predictive factors when treating prostate cancer.

  19. Computed Tomography–Guided Interstitial High-Dose-Rate Brachytherapy in Combination With Regional Positive Lymph Node Intensity-Modulated Radiation Therapy in Locally Advanced Peripheral Non–Small Cell Lung Cancer: A Phase 1 Clinical Trial

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, Li; Zhang, Jian-wen; Lin, Sheng; Luo, Hui-Qun; Wen, Qing-Lian; He, Li-Jia; Shang, Chang-Ling; Ren, Pei-Rong; Yang, Hong-Ru; Pang, Hao-Wen; Yang, Bo; He, Huai-Lin [Department of Oncology, Affiliated Hospital of Luzhou Medical College, Luzhou (China); Chen, Yue, E-mail: chenyue5523@126.com [Department of Nuclear Medicine, Affiliated Hospital of Luzhou Medical College, Luzhou (China); Wu, Jing-Bo, E-mail: wjb6147@163.com [Department of Oncology, Affiliated Hospital of Luzhou Medical College, Luzhou (China)

    2015-08-01

    Purpose: To assess the technical safety, adverse events, and efficacy of computed tomography (CT)-guided interstitial high-dose-rate (HDR) brachytherapy in combination with regional positive lymph node intensity modulated radiation therapy in patients with locally advanced peripheral non–small cell lung cancer (NSCLC). Methods and Materials: Twenty-six patients with histologically confirmed NSCLC were enrolled in a prospective, officially approved phase 1 trial. Primary tumors were treated with HDR brachytherapy. A single 30-Gy dose was delivered to the 90% isodose line of the gross lung tumor volume. A total dose of at least 70 Gy was administered to the 95% isodose line of the planning target volume of malignant lymph nodes using 6-MV X-rays. The patients received concurrent or sequential chemotherapy. We assessed treatment efficacy, adverse events, and radiation toxicity. Results: The median follow-up time was 28 months (range, 7-44 months). There were 3 cases of mild pneumothorax but no cases of hemothorax, dyspnea, or pyothorax after the procedure. Grade 3 or 4 acute hematologic toxicity was observed in 5 patients. During follow-up, mild fibrosis around the puncture point was observed on the CT scans of 2 patients, but both patients were asymptomatic. The overall response rates (complete and partial) for the primary mass and positive lymph nodes were 100% and 92.3%, respectively. The 1-year and 2-year overall survival (OS) rates were 90.9% and 67%, respectively, with a median OS of 22.5 months. Conclusion: Our findings suggest that HDR brachytherapy is safe and feasible for peripheral locally advanced NSCLC, justifying a phase 2 clinical trial.

  20. The Curie–Da Vinci Connection: 5-Years' Experience With Laparoscopic (Robot-Assisted) Implantation for High-Dose-Rate Brachytherapy of Solitary T2 Bladder Tumors

    Energy Technology Data Exchange (ETDEWEB)

    Steen-Banasik, Elzbieta M. van der, E-mail: E.vanderSteen-Banasik@radiotherapiegroep.nl [Radiotherapiegroep, Arnhem (Netherlands); Smits, Geert A.H.J. [Department of Urology, Rijnstate Hospital, Arnhem (Netherlands); Oosterveld, Bernard J.; Janssen, Theo; Visser, Andries G. [Radiotherapiegroep, Arnhem (Netherlands)

    2016-08-01

    Purpose: To report experience and early results of laparoscopic implantation for interstitial brachytherapy (BT) of solitary bladder tumors and the feasibility of a high-dose-rate (HDR) schedule. Methods and Materials: From December 2009 to April 2015, 57 patients with a T2 solitary bladder tumor were treated in Arnhem with transurethral bladder resection followed by external beam irradiation, applied to the bladder and regional iliac lymph nodes, 40 Gy in 20 fractions, 5 fractions per week, and within 1 week interstitial HDR BT, in selected cases combined with partial cystectomy and lymph node dissection. The BT catheters were placed via a transabdominal approach with robotic assistance from a Da Vinci robot after a successful initial experience with a nonrobotic laparoscopic approach. The fraction schedule for HDR was 10 fractions of 2.5 Gy, 3 fractions per day. This was calculated to be equivalent to a reference low-dose-rate schedule of 30 Gy in 60 hours. Data for oncologic outcomes and toxicity (Common Toxicity Criteria version 4) were prospectively collected. Results: These modifications resulted in an average postoperative hospitalization of 6 days, minimal blood loss, and no wound healing problems. Two patients had severe acute toxicity: 1 pulmonary embolism grade 4 and 1 cardiac death. Late toxicity was mild (n=2 urogenital grade 3 toxicity). The median follow-up was 2 years. Using cumulative incidence competing risk analysis, the 2-year overall, disease-free, and disease-specific survival and local control rates were 59%, 71%, 87%, and 82%, respectively. Conclusions: The benefits of minimally invasive surgery for implantation of BT catheters and the feasibility of HDR BT in bladder cancer are documented. The patient outcome and adverse events are comparable to the best results published for a bladder-sparing approach.

  1. Combination of high-dose rate brachytherapy and external beam radiotherapy for the treatment of advanced scalp angiosarcoma - case report; Braquiterapia de alta taxa de dose associada a radioterapia externa no tratamento de angiossarcoma extenso do couro cabeludo - relato de caso

    Energy Technology Data Exchange (ETDEWEB)

    Gentil, Andre Cavalcanti; Lima Junior, Carlos Genesio Bezerra [Instituto Nacional do Cancer, Rio de Janeiro, RJ (Brazil). Dept. de Radioterapia]. E-mail: andregentil@hotmail.com; Soboll, Danyel Scheidegger; Novaes, Paulo Eduardo R.S.; Pereira, Adelino Jose; Pellizon, Antonio Carlos Assis [Hospital do Cancer A.C. Camargo, Sao Paulo, SP (Brazil). Centro de Tratamento e Pequisa

    2001-10-01

    The authors report a case of a patient with an extensive angiosarcoma of the scalp that was submitted only to radiotherapy with a combination of orthovoltage roentgentherapy and high-dose rate brachytherapy, using a mould. The clinical and technical features as well as the therapeutic outcome are presented, and the usefulness and peculiarities of high-dose rate brachytherapy for this particular indication is discussed. A comparative analysis of the difficulties and limitations of employing low-dose rate brachytherapy is also presented. The authors concluded that high-dose rate brachytherapy might be an useful, practical and safe option to treat neoplastic lesions of the scalp, and an alternative treatment to electrontherapy. (author)

  2. High dose-rate brachytherapy as a treatment option in primary tracheal tumors Braquiterapia de alta taxa de dose como opção terapêutica nos tumores primários da traquéia

    Directory of Open Access Journals (Sweden)

    Heloisa de Andrade Carvalho

    2005-08-01

    Full Text Available PURPOSE: To present experience with high dose-rate endobronchial brachytherapy in the treatment of primary tracheal tumors. PATIENTS AND METHODS: Four patients with nonresected primary tracheal tumors are presented: 2 cases of squamous cell carcinoma of the trachea, 1 of recurrent adenoid cystic carcinoma, and 1 with recurrent plasmacytoma. All received brachytherapy, alone or as a boost for primary irradiation, in 3 or 4 fractions of 7.5 Gy, calculated at a depth of 1 cm. Follow-up was considered to start from the end of brachytherapy. RESULTS: Local control was achieved in all cases at the time of first bronchoscopic evaluation. Two patients with squamous cell carcinoma died at 6th and 33rd months after brachytherapy, respectively. The first had no evidence of disease, and the latter had local recurrence. The other 2 patients were alive after 64 and 110 months of follow-up, respectively, both with no evidence of disease. Tracheal stenosis developed in these 2 cases, 22 and 69 months after brachytherapy. Tracheal stent placement was needed only for the patient with an adenoid cystic carcinoma. CONCLUSIONS: Endobronchial high dose-rate brachytherapy may be used for tracheal tumors, even as a boost for external beam irradiation, or in recurrences. Local control in 3 out of 4 patients indicates that individual cases may benefit from the treatment. Long-term survival may also be expected, mainly for tumors with adenoid cystic histology.OBJETIVO: Apresentar a experiência do tratamento de 4 pacientes com tumores primários de traquéia, não operados, submetidos à braquiterapia endobrônquica de alta taxa de dose. PACIENTES E MÉTODOS: Dois casos de carcinoma espinocelular, uma recidiva de carcinoma adenóide cístico e uma recidiva de plasmocitoma primário da traquéia. Todos receberam braquiterapia endobrônquica, exclusiva ou como reforço de dose da radioterapia externa. Foram administradas 3 ou 4 frações de 7,5 Gy cada, calculados a 1 cm de

  3. Attenuation measurements show that the presence of a TachoSil surgical patch will not compromise target irradiation in intra-operative electron radiation therapy or high-dose-rate brachytherapy.

    Science.gov (United States)

    Sarmento, Sandra; Costa, Filipa; Pereira, Alexandre; Lencart, Joana; Dias, Anabela; Cunha, Luís; Sousa, Olga; Silva, José Pedro; Santos, Lúcio

    2015-01-09

    Surgery of locally advanced and/or recurrent rectal cancer can be complemented with intra-operative electron radiation therapy (IOERT) to deliver a single dose of radiation directly to the unresectable margins, while sparing nearby sensitive organs/structures. Haemorrhages may occur and can affect the dose distribution, leading to an incorrect target irradiation. The TachoSil (TS) surgical patch, when activated, creates a fibrin clot at the surgical site to achieve haemostasis. The aim of this work was to determine the effect of TS on the dose distribution, and ascertain whether it could be used in combination with IOERT. This characterization was extended to include high dose rate (HDR) intraoperative brachytherapy, which is sometimes used at other institutions instead of IOERT. CT images of the TS patch were acquired for initial characterization. Dosimetric measurements were performed in a water tank phantom, using a conventional LINAC with a hard-docking system of cylindrical applicators. Percentage Depth Dose (PDD) curves were obtained, and measurements made at the depth of dose maximum for the three clinically used electron energies (6, 9 and 12MeV), first without any attenuator and then with the activated patch of TS completely covering the tip of the IOERT applicator. For HDR brachytherapy, a measurement setup was improvised using a solid water phantom and a Farmer ionization chamber. Our measurements show that the attenuation of a TachoSil patch is negligible, both for high energy electron beams (6 to 12MeV), and for a HDR (192)Ir brachytherapy source. Our results cannot be extrapolated to lower beam energies such as 50 kVp X-rays, which are sometimes used for breast IORT. The TachoSil surgical patch can be used in IORT procedures using 6MeV electron energies or higher, or HDR (192)Ir brachytherapy.

  4. Endophytic fungi of the Genus Penicillium isolated of Platypodium elegans from environments of high dose rate of ionizing radiation; Fungos endofiticos do genero Penicillium isolados de Platypodium elegans provenientes de locais de alta taxa de radiacao

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Victor da

    1999-07-01

    The present work had as objective to isolate and to identify endophytic microorganisms and were exposed to stress situations, using for this ionizing radiations, these highly mutagen and in high doses, lethal to all the alive organisms. The endophytic microorganisms were obtained the starting from the species arboreal Platypodium elegans Vog., one of them developed in radioactive land in the area of Ipora/Go and other, developed in land Background in the city of Abadia de Goias/GO. The rates of dose of environmental radiation were shown sharply different, being in Ipora (Anomaly 2) with a value of approximately 140 {mu}R/h and in Abadia de Goias with approximately 20 {mu}R/H, both measured the area of root of the tree close to. Tests through PCR-RAPD were accomplished with the isolated ones, for verification of the similarity of its genetic characteristics and possible polymorphism among its DNA's . The isolated ones were studied with relationship to the effects of the gamma radiation, being used as source {sup 60} Co, with doses of 25 to 2131 Gy. These lineages had the same behavior practically with relationship to the resistance of the gamma radiation, declining strongly at levels of approximately 700 Gy. The isolated ones tested were identified at microscope for morphology, being of the Genus Penicillium, with the same genetic characteristics in agreement with PCR/RAPD, being just observed a polymorphism area in its DNA's. In spite of a lineage to have been isolated of a tree developed in radioactive land, any difference was observed among its resistance to the gamma radiation in comparison to the isolated lineage of tree developed in land radiometric background. (author)

  5. External beam boost versus interstitial high-dose-rate brachytherapy boost in the adjuvant radiotherapy following breast-conserving therapy in early-stage breast cancer: a dosimetric comparison

    Science.gov (United States)

    Melchert, Corinna; Kovács, György

    2016-01-01

    Purpose This study aims to compare the dosimetric data of local tumor's bed dose escalation (boost) with photon beams (external beam radiation therapy – EBRT) versus high-dose-rate interstitial brachytherapy (HDR-BT) after breast-conserving treatment in women with early-stage breast cancer. Material and methods We analyzed the treatment planning data of 136 irradiated patients, treated between 2006 and 2013, who underwent breast-conserving surgery and adjuvant whole breast irradiation (WBI; 50.4 Gy) and boost (HDR-BT: 10 Gy in one fraction [n = 36]; EBRT: 10 Gy in five fractions [n = 100]). Organs at risk (OAR; heart, ipsilateral lung, skin, most exposed rib segment) were delineated. Dosimetric parameters were calculated with the aid of dose-volume histograms (DVH). A non-parametric test was performed to compare the two different boost forms. Results There was no difference for left-sided cancers regarding the maximum dose to the heart (HDR-BT 29.8% vs. EBRT 29.95%, p = 0.34). The maximum doses to the other OAR were significantly lower for HDR-BT (Dmax lung 47.12% vs. 87.7%, p skin 57.1% vs. 94.75%, p < 0.01; in the case of right-sided breast irradiation, dose of the heart 6.00% vs. 16.75%, p < 0.01). Conclusions Compared to EBRT, local dose escalation with HDR-BT presented a significant dose reduction to the investigated OAR. Only left-sided irradiation showed no difference regarding the maximum dose to the heart. Reducing irradiation exposure to OAR could result in a reduction of long-term side effects. Therefore, from a dosimetric point of view, an interstitial boost complementary to WBI via EBRT seems to be more advantageous in the adjuvant radiotherapy of breast cancer. PMID:27648082

  6. External beam boost versus interstitial high-dose-rate brachytherapy boost in the adjuvant radiotherapy following breast-conserving therapy in early-stage breast cancer: a dosimetric comparison

    Directory of Open Access Journals (Sweden)

    Martje Marie Terheyden

    2016-08-01

    Full Text Available Purpose : This study aims to compare the dosimetric data of local tumor’s bed dose escalation (boost with photon beams (external beam radiation therapy – EBRT versus high-dose-rate interstitial brachytherapy (HDR-BT after breast-conserving treatment in women with early-stage breast cancer. Material and methods : We analyzed the treatment planning data of 136 irradiated patients, treated between 2006 and 2013, who underwent breast-conserving surgery and adjuvant whole breast irradiation (WBI; 50.4 Gy and boost (HDR-BT: 10 Gy in one fraction [n = 36]; EBRT: 10 Gy in five fractions [n = 100]. Organs at risk (OAR; heart, ipsilateral lung, skin, most exposed rib segment were delineated. Dosimetric parameters were calculated with the aid of dose-volume histograms (DVH. A non-parametric test was performed to compare the two different boost forms. Results : There was no difference for left-sided cancers regarding the maximum dose to the heart (HDR-BT 29.8% vs. EBRT 29.95%, p = 0.34. The maximum doses to the other OAR were significantly lower for HDR-BT (Dmax lung 47.12% vs. 87.7%, p < 0.01; rib 61.17% vs. 98.5%, p < 0.01; skin 57.1% vs. 94.75%, p < 0.01; in the case of right-sided breast irradiation, dose of the heart 6.00% vs. 16.75%, p < 0.01. Conclusions : Compared to EBRT, local dose escalation with HDR-BT presented a significant dose reduction to the investigated OAR. Only left-sided irradiation showed no difference regarding the maximum dose to the heart. Reducing irradiation exposure to OAR could result in a reduction of long-term side effects. Therefore, from a dosimetric point of view, an interstitial boost complementary to WBI via EBRT seems to be more advantageous in the adjuvant radiotherapy of breast cancer.

  7. Urethra low-dose tunnels: validation of and class solution for generating urethra-sparing dose plans using inverse planning simulated annealing for prostate high-dose-rate brachytherapy.

    Science.gov (United States)

    Cunha, J Adam M; Pouliot, Jean; Weinberg, Vivian; Wang-Chesebro, Alice; Roach, Mack; Hsu, I-Chow

    2012-01-01

    Urethral dose is related to severity of genitourinary toxicity in patients treated with brachytherapy for prostate cancer. This work describes a dose planning method that uses inverse planning to create a low-dose tunnel around the urethra and presents a class solution to achieve this additional dose sparing of the urethra. Fifteen patients on the Radiation Therapy Oncology Group (RTOG) 0321 protocol were treated for prostate cancer with a high-dose-rate brachytherapy dose boost to an external beam radiation treatment regimen. All were treated with 9.5Gy for each of the two fractions after 45Gy of the external beam radiation. The inverse-planning algorithm, inverse planning simulated annealing (IPSA), was used to create both the standard RTOG protocol (SRP) plan for treatment and the a posteriori urethra dose sparing (UDS) plan consisting of a dose tunnel along the urethra. Both plans maintained the protocol parameters: prostate V(100) (volume receiving 100% of prescribed dose)>90% and bladder and rectum V(75)90%, with mean for the SRP V(100)=93% versus UDS plan V(100)=90%. Prostate D(90) for SRP was 104% versus UDS plan D(90)=101%. For all patients, the UDS achieved a dose tunnel surrounding the length of the intraprostatic urethra. The class solution for generating UDS is presented. A urethral sparing-focused planning solution using IPSA reduces mean urethral dose by 34%, as compared with IPSA-generated plans based on the RTOG 0321 protocol. This is done while maintaining prostate coverage and critical structure dose. This technique can be applied to all patients in whom urethra toxicity is of particular concern. Copyright © 2012 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  8. Acute and late vaginal toxicity after adjuvant high-dose-rate vaginal brachytherapy in patients with intermediate risk endometrial cancer: is local therapy with hyaluronic acid of clinical benefit?

    Directory of Open Access Journals (Sweden)

    Concetta Laliscia

    2016-12-01

    Full Text Available Purpose : The aim of the present study was to evaluate the effectiveness of hyaluronic acid (HA in the prevention of acute and late vaginal toxicities after high-dose-rate (HDR vaginal brachytherapy (BT. Material and methods : Between January 2011 and January 2015, we retrospectively analyzed 126 patients with endometrial cancer who underwent extrafascial hysterectomy with or without lymphadenectomy and adjuvant HDR-vaginal BT +/– adjuvant chemotherapy. The total dose prescription was 21 Gy in 3 fractions (one fraction for week. Vaginal ovules containing 5 mg of HA were given for whole duration of vaginal BT and for the two following weeks. Acute and late toxicities were evaluated according to CTCAE vs 4.02. Results : According to the revised FIGO 2009 classification, most tumors were in stage IA (30.9% and in stage IB (57.9%. Thirty-three patients (26.2% received adjuvant chemotherapy before vaginal BT. Five-year disease-free survival (DFS and five-year overall survival (OS were 88% and 93%, respectively. The most common grade 1-2 acute toxicities were vaginal inflammation (18 patients, 14.3% and dyspareunia (7 patients, 5.5%. Two patients (1.6% had more than one toxicity. Late toxicity occurred in 20 patients (15.9%. Grade 1-2 late toxicities were fibrosis (14 patients, 11.1% and telangiectasias (7 patients, 5.5%. Six patients (4.8% had more than one late toxicity. No grade 3 or higher acute or late toxicities were observed. Conclusions : These results appear to suggest that the local therapy with HA is of clinical benefit for intermediate risk endometrial cancer patients who receive adjuvant HDR-vaginal BT after surgery. A randomized trial comparing HA treatment vs. no local treatment in this clinical setting is warranted to further evaluate the efficacy of HA in preventing vaginal BT-related vaginal toxicity.

  9. Single-fraction high-dose-rate brachytherapy using real-time transrectal ultrasound based planning in combination with external beam radiotherapy for prostate cancer: dosimetrics and early clinical results

    Directory of Open Access Journals (Sweden)

    Olivier Lauche

    2016-04-01

    Full Text Available Purpose : To validate the feasibility of a single-fraction high-dose-rate brachytherapy (HDRBT boost for prostate cancer using real-time transrectal ultrasound (TRUS based planning. Material and methods : From August 2012 to September 2015, 126 patients underwent a single-fraction HDRBT boost of 15 Gy using real-time TRUS based planning. External beam radiation therapy (EBRT (37.5 Gy/15 fractions, 44 Gy/22 fractions, or 45 Gy/25 fractions was performed before (31% or after (69% HDRBT boost. Genito-urinary (GU and gastro-intestinal (GI toxicity were assessed 4 and 12 months after the end of combined treatment using the international prostate symptom score scale (IPSS and the common terminology criteria for adverse events (CTCAE v3.0. Results : All dose-planning objectives were achieved in 90% of patients. Prostate D 90 ≥ 105% and ≤ 115% was achieved in 99% of patients, prostate V 150 ≤ 40% in 99%, prostate V 200 < 11% in 96%, urethra D 10 < 120% for 99%, urethra V 125 = 0% in 100%, and rectal V 75 < 1 cc in 93% of patients. Median IPSS score was 4 at baseline and did not change at 4 and 12 months after combined treatment. No patients developed ≥ grade 2 GI toxicity. With a median follow-up of 10 months, only two patients experienced biochemical failure. Among patients who didn’t receive ADT, cumulative percentage of patients with PSA ≤ 1 ng/ml at 4 and 18 months was respectively 23% and 66%. Conclusions : Single-fraction HDRBT boost of 15 Gy using real-time TRUS based planning achieves consistently high dosimetry quality. In combination with EBRT, toxicity outcomes appear promising. A longer follow-up is needed to assess long-term outcome and toxicities.

  10. Dosimetric systems of high dose, dose rate and dose uniformity in food and medical products; Sistemas dosimetricos de altas dosis, tasa de dosis y uniformidad de dosis en alimentos y producto medico

    Energy Technology Data Exchange (ETDEWEB)

    Vargas, J.; Vivanco, M.; Castro, E., E-mail: jvargas@ipen.gob.pe [Instituto Peruano de Energia Nuclear, Av. Canada 1470, San Borja, Lima (Peru)

    2014-08-15

    In the Instituto Peruano de Energia Nuclear (IPEN) we use the chemical dosimetry Astm-E-1026 Fricke as a standard dosimetric system of reference and different routine dosimetric systems of high doses, according to the applied doses to obtain the desired effects in the treated products and the doses range determined for each type of dosimeter. Fricke dosimetry is a chemical dosimeter in aqueous solution indicating the absorbed dose by means an increase in absorbance at a specific wavelength. A calibrated spectrophotometer with controlled temperature is used to measure absorbance. The adsorbed dose range should cover from 20 to 400 Gy, the Fricke solution is extremely sensitive to organic impurities, to traces of metal ions, in preparing chemical products of reactive grade must be used and the water purity is very important. Using the referential standard dosimetric system Fricke, was determined to March 5, 2013, using the referential standard dosimetric system Astm-1026 Fricke, were irradiated in triplicate Fricke dosimeters, to 5 irradiation times (20; 30; 40; 50 and 60 seconds) and by linear regression, the dose rate of 5.400648 kGy /h was determined in the central point of the irradiation chamber (irradiator Gamma cell 220 Excel), applying the decay formula, was compared with the obtained results by manufacturers by means the same dosimetric system in the year of its manufacture, being this to the date 5.44691 kGy /h, with an error rate of 0.85. After considering that the dosimetric solution responds to the results, we proceeded to the irradiation of a sample of 200 g of cereal instant food, 2 dosimeters were placed at the lateral ends of the central position to maximum dose and 2 dosimeters in upper and lower ends as minimum dose, they were applied same irradiation times; for statistical analysis, the maximum dose rate was 6.1006 kGy /h and the minimum dose rate of 5.2185 kGy /h; with a dose uniformity of 1.16. In medical material of micro pulverized bone for

  11. Cervical Gross Tumor Volume Dose Predicts Local Control Using Magnetic Resonance Imaging/Diffusion-Weighted Imaging—Guided High-Dose-Rate and Positron Emission Tomography/Computed Tomography—Guided Intensity Modulated Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Dyk, Pawel; Jiang, Naomi; Sun, Baozhou; DeWees, Todd A. [Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States); Fowler, Kathryn J.; Narra, Vamsi [Department of Diagnostic Radiology, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Missouri (United States); Garcia-Ramirez, Jose L.; Schwarz, Julie K. [Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States); Grigsby, Perry W., E-mail: pgrigsby@wustl.edu [Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States); Division of Nuclear Medicine, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Missouri (United States); Division of Gynecologic Oncology, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Missouri (United States); Alvin J. Siteman Cancer Center, Washington University School of Medicine, St Louis, Missouri (United States)

    2014-11-15

    Purpose: Magnetic resonance imaging/diffusion weighted-imaging (MRI/DWI)-guided high-dose-rate (HDR) brachytherapy and {sup 18}F-fluorodeoxyglucose (FDG) — positron emission tomography/computed tomography (PET/CT)-guided intensity modulated radiation therapy (IMRT) for the definitive treatment of cervical cancer is a novel treatment technique. The purpose of this study was to report our analysis of dose-volume parameters predicting gross tumor volume (GTV) control. Methods and Materials: We analyzed the records of 134 patients with International Federation of Gynecology and Obstetrics stages IB1-IVB cervical cancer treated with combined MRI-guided HDR and IMRT from July 2009 to July 2011. IMRT was targeted to the metabolic tumor volume and lymph nodes by use of FDG-PET/CT simulation. The GTV for each HDR fraction was delineated by use of T2-weighted or apparent diffusion coefficient maps from diffusion-weighted sequences. The D100, D90, and Dmean delivered to the GTV from HDR and IMRT were summed to EQD2. Results: One hundred twenty-five patients received all irradiation treatment as planned, and 9 did not complete treatment. All 134 patients are included in this analysis. Treatment failure in the cervix occurred in 24 patients (18.0%). Patients with cervix failures had a lower D100, D90, and Dmean than those who did not experience failure in the cervix. The respective doses to the GTV were 41, 58, and 136 Gy for failures compared with 67, 99, and 236 Gy for those who did not experience failure (P<.001). Probit analysis estimated the minimum D100, D90, and Dmean doses required for ≥90% local control to be 69, 98, and 260 Gy (P<.001). Conclusions: Total dose delivered to the GTV from combined MRI-guided HDR and PET/CT-guided IMRT is highly correlated with local tumor control. The findings can be directly applied in the clinic for dose adaptation to maximize local control.

  12. SU-F-T-32: Evaluation of the Performance of a Multiple-Array-Diode Detector for Quality Assurance Tests in High-Dose-Rate Brachytherapy with Ir-192 Source

    Energy Technology Data Exchange (ETDEWEB)

    Harpool, K; De La Fuente Herman, T; Ahmad, S; Ali, I [University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States)

    2016-06-15

    Purpose: To evaluate the performance of a two-dimensional (2D) array-diode- detector for geometric and dosimetric quality assurance (QA) tests of high-dose-rate (HDR) brachytherapy with an Ir-192-source. Methods: A phantom setup was designed that encapsulated a two-dimensional (2D) array-diode-detector (MapCheck2) and a catheter for the HDR brachytherapy Ir-192 source. This setup was used to perform both geometric and dosimetric quality assurance for the HDR-Ir192 source. The geometric tests included: (a) measurement of the position of the source and (b) spacing between different dwell positions. The dosimteric tests include: (a) linearity of output with time, (b) end effect and (c) relative dose verification. The 2D-dose distribution measured with MapCheck2 was used to perform the previous tests. The results of MapCheck2 were compared with the corresponding quality assurance testes performed with Gafchromic-film and well-ionization-chamber. Results: The position of the source and the spacing between different dwell-positions were reproducible within 1 mm accuracy by measuring the position of maximal dose using MapCheck2 in contrast to the film which showed a blurred image of the dwell positions due to limited film sensitivity to irradiation. The linearity of the dose with dwell times measured from MapCheck2 was superior to the linearity measured with ionization chamber due to higher signal-to-noise ratio of the diode readings. MapCheck2 provided more accurate measurement of the end effect with uncertainty < 1.5% in comparison with the ionization chamber uncertainty of 3%. Although MapCheck2 did not provide absolute calibration dosimeter for the activity of the source, it provided accurate tool for relative dose verification in HDR-brachytherapy. Conclusion: The 2D-array-diode-detector provides a practical, compact and accurate tool to perform quality assurance for HDR-brachytherapy with an Ir-192 source. The diodes in MapCheck2 have high radiation sensitivity and

  13. Braquiterapia intersticial de alta tasa de rescate en cáncer cabeza cuello previamente radiado High-dose-rate (HDR brachytherapy in previously irradiated recurrent head and neck cancer

    Directory of Open Access Journals (Sweden)

    Lucía Gutiérrez-Bayard

    2011-09-01

    Full Text Available A pesar de los avances en el tratamiento de cáncer de cabeza y cuello (CCC, el 15-50% de los pacientes presentan recurrencia locorregional. Para los pacientes que presentan enfermedad localmente recurrente o un segundo tumor primario en un campo previamente irradiado, las opciones terapéuticas de rescate son limitadas, siendo la resección quirúrgica con intención curativa la opción de elección para los pacientes con enfermedad limitada. Reirradiación con o sin la adición de quimioterapia puede ser una buena opción, obteniendo en pacientes seleccionados supervivencia a largo plazo. La braquiterapia de alta tasa de dosis (HDRBT puede jugar un papel importante en el tratamiento de rescate en tumores de cabeza y cuello recurrentes. Presentamos un paciente de 56 años diagnosticado de cáncer de lengua sometido a cirugía y radioterapia externa adyuvante, y recurrencia metastásica ganglionar cervical contralateral a los 18 meses. Recibió tratamiento multidisciplinar con quimioterapia, cirugía y braquiterapia intersticial.Despite advances in the treatment of head and neck cancer (HNC, 15-50% of patients present locoregional disease recurrence. The therapeutic options are limited for patients who present locally recurrent disease or a second primary tumor in a previously irradiated field. Surgical salvage with curative intent is the preferred option for patients with limited-volume disease. Re-irradiation with or without the addition of chemotherapy may hold promise for long-term survival for selected patients. High-dose-rate (HDR brachytherapy can play an important role in the salvage treatment of previously irradiated recurrent head and neck cancer. The case reported was a 56-year old man diagnosed of tongue cancer who presented recurrent metastatic contralateral cervical node 1.5 years after radical treatment with surgery and adjuvant external radiotherapy. He received multidisciplinary treatment with chemotherapy, surgery and HDR

  14. High-dose rate brachytherapy of prostatic adenocarcinoma in combination with external beam radiotherapy. A long-term follow-up of the first 50 patients at one center

    Energy Technology Data Exchange (ETDEWEB)

    Lennernaes, B. [Dept. of Oncology, Sahlgrenska Univ. Hospital (Sweden); Holmaeng, S. [Dept. of Urology, Sahlgrenska Univ. Hospital (Sweden); Hedelin, H. [Kaernsjukhuset, Skoevde (Sweden)

    2002-10-01

    Aim: To report the long-term follow-up of 50 patients with prostatic adenocarcinoma (PAC) by high-dose rate brachytherapy in combination with external beam radiotherapy. Patients and methods: Between 1988 and 1995, 50 patients were treated with external beam radiotherapy delivered in 2 Gy fractions to a total dose of 50 Gy. Brachytherapy was delivered in two 10 Gy fractions. The mean follow-up time was 7.2 years. Results: 42 patients are alive and four patients have deceased of prostatic adenocarcinoma. Of the remaining patients, 40 have a PSA<1 ng/l. 41 patients were interviewed during the year 2000 and 91% of these were satisfied with the treatment. Four (8%) patients reported grade III/IV side effects. Ten of the 41 patients reported that they still had an erection allowing intercourse. Half of those who developed an erectile dysfunction did so in direct connection with the treatment. In the others erectile dysfunction developed gradually during the first 48 months after the treatment. Conclusion: The combined treatment gave an exceptionally good local control (86%). The method represents a promising curative treatment, but the effect can be double edged. The small number of patients in this study restricts a more conclusive statement concerning this treatment modality. (orig.) [German] Ziel: Monoinstitutioneller Erfahrungsbericht zur Behandlung des Prostatakarzinoms mit kombinierter externer und HDR-Brachytherapie. Patienten und Methoden: Von 1988 bis 1995 wurden 50 Patienten mit einem Prostataadenokarzinom kombiniert extern und interstitiell behandelt. Die perkutane Radiotherapie erfolgte bei einer Einzeldosis von 2 Gy bis zu einer Gesamtreferenzdosis von 50 Gy. Die Brachtherapie folgte mittels zweier HDR-Fraktionen von je 10 Gy. Die mediane Nachbeobachtungszeit betrug 7,2 Jahre. Ergebnisse: 42 Patienten sind am Leben, vier starben am Prostataadenokarzinom. Von den ueberlebenden Patienten haben 40 einen PSA-Wert <1 ng/l. 41 Patienten wurden waehrend des Jahres

  15. Conformation and trapping rate of DNA at a convergent stagnation point.

    Science.gov (United States)

    Kreft, Jennifer; Chen, Yeng-Long; Chang, Hsueh-Chia

    2008-03-01

    We use a lattice-Boltzmann based Brownian dynamics simulation to investigate the elongation of DNA at a convergent stagnation point trapped by a uniform attractive potential. The trapping rate of the DNA is not sensitive to the potential and, consistent with a mean field theory, scales as the Peclet number, Pe(1/3) . Surprisingly, we find that the coiled state is favored over the stretched state at high Pe. The final elongation is determined by conformation changes during transport to the stagnation point, rather than hydrodynamic stretching at that point.

  16. Proposal of a postal system for Ir-192 sources calibration used in high dose rate brachytherapy with LiF:Mn:Ti thermoluminescent dosemeters; Proposta de um sistema postal para a calibracao de fontes de {sup 192} Ir, utilizadas em braquiterapia de alta taxa de dose, com dosimetros termoluminescentes de LiF: Mn: Ti

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, W.S.; Borges, J.C.; Almeida, C.E.V. [Instituto de Radioprotecao e Dosimetria. CNEN Caixa Postal 37750, 22780-160, Rio de Janeiro (Brazil)

    1998-12-31

    A proposal in order to improve the brachytherapy quality control and to allow postal intercomparison of Ir-192 sources used in high dose rate brachytherapy has been presented. The LiF: Mn: Ti (TLD 100) detector has been selected for such purpose. The experimental array and the TLDs irradiation and calibration techniques, at the treatment units, have been specified in the light of more recent methodology of Ir-192 calibration sources. (Author)

  17. Asymptotic weight and maturing rate in mice selected for body conformation

    Directory of Open Access Journals (Sweden)

    Di Masso Ricardo J.

    2000-01-01

    Full Text Available Growth patterns of four lines of mice selected for body conformation were analyzed with the logistic function, in order to provide baseline information about the relationship between asymptotic weight and maturing rate of body weight. Two lines were divergently selected favoring the phenotypic correlation between body weight and tail length (agonistic selection: CBi+, high body weight and long tail; CBi-, low body weight and short tail, whereas the other two lines were generated by a disruptive selection performed against the correlation between the aforementioned traits (antagonistic selection: CBi/C, high body weight and short tail; CBi/L, low body weight and long tail. The logistic parameters A (asymptotic weight and k (maturing rate behaved in CBi/C and CBi- mice and in CBi+ females as expected in terms of the negative genetic relationship between mature size and earliness of maturing. An altered growth pattern was found in CBi/L mice and in CBi+ males, because in the former genotype, selected for low body weight, the time taken to mature increased, whereas in the latter, selected for high body weight, there was a non-significant increase in the same trait. In accordance with the selective criterion, different sources of genetic variation for body weight could be exploited: one inversely associated with earliness of maturing (agonistic selection, and the other independent of maturing rate (antagonistic selection, showing that genetic variation of A is partly independent of k.

  18. High-Dose Phenobarbital for Ohtahara Syndrome

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2002-05-01

    Full Text Available Oral high-dose phenobarbital therapy was effective in the control of tonic spasms in a 1 month-old-infant with early infantile epileptic encephalopathy with suppression bursts (Ohtahara syndrome treated at Tokyo Metropolitan Hachioji Children’s Hospital, Tokyo, Japan.

  19. Feasibility and toxicity of a single fraction high-dose-rate brachytherapy followed by a course of EBRT for localized prostate cancer, a retrospective study: the Polyclinique Courlancy experience; Faisabilite et toxicite d'une seance unique de curietherapie de haut debit de dose suivie d'une irradiation externe dans le cancer localise de la prostate: etude retrospective de la polyclinique de Courlancy

    Energy Technology Data Exchange (ETDEWEB)

    Mallet, F.; Wdowczyk, D.; Bruna, A.; Joffroy, P.; Pangrazzi, T. [Centre de radiotherapie et d' oncologie, polyclinique Courlancy, Service de radiotherapie, 51 - Reims (France); Villena, P.; Herard, A.; Amory, J.P. [Cabinet d' urologie, polyclinique Courlancy, 51 - Reims (France)

    2010-01-15

    Purpose Evaluate the feasibility and toxicity of radiation dose escalation delivered with a single fraction high-dose-rate (H.D.R.) brachytherapy boost followed by external beam radiotherapy for intermediate and high risk localized prostate cancer - a retrospective study. Patients and methods: Between December 2004 and December 2008, 61 patients with intermediate risk or high-risk localized prostate cancer received a single 10 Gy fraction of interstitial H.D.R. brachytherapy followed by a 64 Gy course of external beam radiation therapy. Dose volume histograms, conformity index and side effects were systematically analyzed. Result; H.D.R. brachytherapy dosimetric criteria were respected. Early side effects (= 3 months after full treatment): 30 % reported grade 2 or grade 3 urinary toxicity and 26 % reported grade 2 or grade 3 bowel toxicity were reported. Late side effects (> 3 months): 12 % reported grade 2 or grade 3 urinary toxicity and 5 % reported grade 2 or grade 3 bowel toxicity were reported. No patients reported any grade 4 late toxicity events. Three months after treatment, 7 % grade 1, 25 % grade 2 and 39 % grade 3 erectile dysfunction were reported. Conclusion. Our mono fractionation protocol is an easy technique to implement logistically. Acute and late toxicities are acceptable and comparable to those published by various teams mostly using multi fractionation protocols. A longer follow-up is required to assess the effect of this dose escalation protocol on long-term biological control. (authors)

  20. High-dose neutron detector project update

    Energy Technology Data Exchange (ETDEWEB)

    Menlove, Howard Olsen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Henzlova, Daniela [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-10

    These are the slides for a progress review meeting by the sponsor. This is an update on the high-dose neutron detector project. In summary, improvements in both boron coating and signal amplification have been achieved; improved boron coating materials and procedures have increased efficiency by ~ 30-40% without the corresponding increase in the detector plate area; low dead-time via thin cell design (~ 4 mm gas gaps) and fast amplifiers; prototype PDT 8” pod has been received and testing is in progress; significant improvements in efficiency and stability have been verified; use commercial PDT 10B design and fabrication to obtain a faster path from the research to practical high-dose neutron detector.

  1. High-dose midazolam infusion for refractory status epilepticus.

    Science.gov (United States)

    Fernandez, Andres; Lantigua, Hector; Lesch, Christine; Shao, Belinda; Foreman, Brandon; Schmidt, J Michael; Hirsch, Lawrence J; Mayer, Stephan A; Claassen, Jan

    2014-01-28

    This study compares 2 treatment protocols allowing low vs high continuous IV midazolam (cIV-MDZ) doses. We compared adults with refractory status epilepticus treated with a protocol allowing for high-dose cIV-MDZ (n = 100; 2002-2011) with those treated with the previous lower-dose cIV-MDZ (n = 29; 1996-2000). We collected data on baseline characteristics, cIV-MDZ doses, seizure control, hospital course, and outcome. Median maximum cIV-MDZ dose was 0.4 mg/kg/h (interquartile range [IQR] 0.2, 1.0) for the high-dose group and 0.2 mg/kg/h (IQR 0.1, 0.3) for the low-dose group (p cIV-MDZ start was 1 day (IQR 1, 3) for the high-dose group and 2 days (IQR 1, 5) for the low-dose group (p = 0.016). "Withdrawal seizures" (occurring within 48 hours of discontinuation of cIV-MDZ) were less frequent in the high-dose group (15% vs 64%, odds ratio 0.10, 95% confidence interval 0.03-0.27). "Ultimate cIV-MDZ failure" (patients requiring change to a different cIV antiepileptic medication) and hospital complications were not different between groups. Hypotension was more frequent with higher cIV-MDZ doses but was not associated with worse outcome. Discharge mortality was lower in the high-dose group (40% vs 62%, odds ratio 0.34, 95% confidence interval 0.13-0.92 in multivariate analysis). High-dose cIV-MDZ treatment of refractory status epilepticus can be performed safely, is associated with a lower seizure rate after cIV-MDZ discontinuation, and may be associated with lower mortality than traditional lower-dose protocols. This study provides Class III evidence that midazolam at higher infusion rates is associated with a reduction in seizure recurrence within 48 hours after discontinuation and may be associated with lower mortality.

  2. Braquiterapia de alta taxa de dose associada a radioterapia externa no tratamento de angiossarcoma extenso do couro cabeludo: relato de caso Combination of high-dose rate brachytherapy and external beam radiotherapy for the treatment of advanced scalp angiosarcoma: case report

    Directory of Open Access Journals (Sweden)

    André Cavalcanti Gentil

    2001-10-01

    Full Text Available Os autores apresentam um caso de extenso angiossarcoma do couro cabeludo submetido a radioterapia exclusiva, pela associação de roentgenterapia de ortovoltagem e braquiterapia de alta taxa de dose utilizando um molde. Descrevem os aspectos clínicos, técnicos e a evolução terapêutica. Destacam as particularidades e a utilidade da braquiterapia de alta taxa de dose, nesta situação em particular, e fazem uma análise comparativa das dificuldades e limitações caso a braquiterapia de baixa taxa de dose fosse empregada. Concluem ser a braquiterapia de alta taxa de dose uma opção útil, prática e segura para as lesões neoplásicas superficiais do escalpe, podendo ser considerada uma alternativa ao tratamento com elétrons.The authors report a case of a patient with an extensive angiosarcoma of the scalp that was submitted only to radiotherapy with a combination of orthovoltage roentgentherapy and high-dose rate brachytherapy, using a mould. The clinical and technical features as well as the therapeutic outcome are presented, and the usefulness and peculiarities of high-dose rate brachytherapy for this particular indication is discussed. A comparative analysis of the difficulties and limitations of employing low-dose rate brachytherapy is also presented. The authors concluded that high-dose rate brachytherapy might be an useful, practical and safe option to treat neoplastic lesions of the scalp, and an alternative treatment to electrontherapy.

  3. Rate of hydrolysis in ATP synthase is fine-tuned by  -subunit motif controlling active site conformation

    KAUST Repository

    Beke-Somfai, T.

    2013-01-23

    Computer-designed artificial enzymes will require precise understanding of how conformation of active sites may control barrier heights of key transition states, including dependence on structure and dynamics at larger molecular scale. F(o)F(1) ATP synthase is interesting as a model system: a delicate molecular machine synthesizing or hydrolyzing ATP using a rotary motor. Isolated F(1) performs hydrolysis with a rate very sensitive to ATP concentration. Experimental and theoretical results show that, at low ATP concentrations, ATP is slowly hydrolyzed in the so-called tight binding site, whereas at higher concentrations, the binding of additional ATP molecules induces rotation of the central γ-subunit, thereby forcing the site to transform through subtle conformational changes into a loose binding site in which hydrolysis occurs faster. How the 1-Å-scale rearrangements are controlled is not yet fully understood. By a combination of theoretical approaches, we address how large macromolecular rearrangements may manipulate the active site and how the reaction rate changes with active site conformation. Simulations reveal that, in response to γ-subunit position, the active site conformation is fine-tuned mainly by small α-subunit changes. Quantum mechanics-based results confirm that the sub-Ångström gradual changes between tight and loose binding site structures dramatically alter the hydrolysis rate.

  4. Partial breast irradiation: high dose rate per-operative brachytherapy technique using the MammoSite; Irradiation partielle du sein: technique de curietherapie de haut debit de dose apres l'implantation peroperatoire du dispositif MammoSite

    Energy Technology Data Exchange (ETDEWEB)

    Belkacemi, Y.; Poupon, L.; Castellanos, M.E.; Villette, S.; Lartigau, E. [Centre de Lutte Contre le Cancer Oscar-Lambret, Dept. de Radiotherapie, 59 - Lille (France); Chauvet, M.P.; Giard, S. [Centre de Lutte Contre le Cancer Oscar-Lambret, Dept. de Chirurgie Senologique, 59 - Lille (France); Bonodeau, F. [de Lutte Contre le Cancer Oscar-Lambret, Dept. de Radiologie, 59 - Lille (France); Cabaret, V. [de Lutte Contre le Cancer Oscar-Lambret, Dept. d' Anatomopathologie, 59 - Lille (France)

    2003-11-01

    In the conservative management of breast cancer, radiation therapy delivering 45 to 50 Gy to the whole breast, in 4.5 to 5 weeks, followed by a booster dose of 10 to 20 Gy is the standard of care. Based on the numerous studies which have reported that the local recurrences occurs within and surrounding the primary tumor site and in order to decrease the treatment duration and its morbidity, partial breast irradiation using several techniques has been developed. Partial irradiation may be considered as an alternative local adjuvant treatment for selected patients with favorable prognostic factors. Using external beam radiation therapy, the 3D-conformal technique is appropriate to deliver the whole dose to a limited volume. In UK, an intraoperative technique using a miniature beam of low energy of X-ray (50 kV) has been developed (Targit). Milan's team have developed an intraoperative electrons beam radiotherapy using a dedicated linear accelerator in the operative room. In USA and Canada the MammoSite has been advised for clinical use in per-operative brachytherapy of the breast. These two last techniques are currently compared in phase III randomized studies to the standard whole breast irradiation followed by a tumour bed booster dose. In this review we will focus on the MammoSite technique and will describe the per-operative implantation procedure. radiological controls ad dosimetric aspects. (author)

  5. Spectroscopic gamma camera for use in high dose environments

    Science.gov (United States)

    Ueno, Yuichiro; Takahashi, Isao; Ishitsu, Takafumi; Tadokoro, Takahiro; Okada, Koichi; Nagumo, Yasushi; Fujishima, Yasutake; Kometani, Yutaka; Suzuki, Yasuhiko; Umegaki, Kikuo

    2016-06-01

    We developed a pinhole gamma camera to measure distributions of radioactive material contaminants and to identify radionuclides in extraordinarily high dose regions (1000 mSv/h). The developed gamma camera is characterized by: (1) tolerance for high dose rate environments; (2) high spatial and spectral resolution for identifying unknown contaminating sources; and (3) good usability for being carried on a robot and remotely controlled. These are achieved by using a compact pixelated detector module with CdTe semiconductors, efficient shielding, and a fine resolution pinhole collimator. The gamma camera weighs less than 100 kg, and its field of view is an 8 m square in the case of a distance of 10 m and its image is divided into 256 (16×16) pixels. From the laboratory test, we found the energy resolution at the 662 keV photopeak was 2.3% FWHM, which is enough to identify the radionuclides. We found that the count rate per background dose rate was 220 cps h/mSv and the maximum count rate was 300 kcps, so the maximum dose rate of the environment where the gamma camera can be operated was calculated as 1400 mSv/h. We investigated the reactor building of Unit 1 at the Fukushima Dai-ichi Nuclear Power Plant using the gamma camera and could identify the unknown contaminating source in the dose rate environment that was as high as 659 mSv/h.

  6. Spectroscopic gamma camera for use in high dose environments

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, Yuichiro, E-mail: yuichiro.ueno.bv@hitachi.com [Research and Development Group, Hitachi, Ltd., Hitachi-shi, Ibaraki-ken 319-1221 (Japan); Takahashi, Isao; Ishitsu, Takafumi; Tadokoro, Takahiro; Okada, Koichi; Nagumo, Yasushi [Research and Development Group, Hitachi, Ltd., Hitachi-shi, Ibaraki-ken 319-1221 (Japan); Fujishima, Yasutake; Kometani, Yutaka [Hitachi Works, Hitachi-GE Nuclear Energy, Ltd., Hitachi-shi, Ibaraki-ken (Japan); Suzuki, Yasuhiko [Measuring Systems Engineering Dept., Hitachi Aloka Medical, Ltd., Ome-shi, Tokyo (Japan); Umegaki, Kikuo [Faculty of Engineering, Hokkaido University, Sapporo-shi, Hokkaido (Japan)

    2016-06-21

    We developed a pinhole gamma camera to measure distributions of radioactive material contaminants and to identify radionuclides in extraordinarily high dose regions (1000 mSv/h). The developed gamma camera is characterized by: (1) tolerance for high dose rate environments; (2) high spatial and spectral resolution for identifying unknown contaminating sources; and (3) good usability for being carried on a robot and remotely controlled. These are achieved by using a compact pixelated detector module with CdTe semiconductors, efficient shielding, and a fine resolution pinhole collimator. The gamma camera weighs less than 100 kg, and its field of view is an 8 m square in the case of a distance of 10 m and its image is divided into 256 (16×16) pixels. From the laboratory test, we found the energy resolution at the 662 keV photopeak was 2.3% FWHM, which is enough to identify the radionuclides. We found that the count rate per background dose rate was 220 cps h/mSv and the maximum count rate was 300 kcps, so the maximum dose rate of the environment where the gamma camera can be operated was calculated as 1400 mSv/h. We investigated the reactor building of Unit 1 at the Fukushima Dai-ichi Nuclear Power Plant using the gamma camera and could identify the unknown contaminating source in the dose rate environment that was as high as 659 mSv/h.

  7. Studying the Relationship between Rate of Organizational Socialization and Rate of Employees Conformity (Group Stress, Kind of Character, Individualism Culture and Pluralism Culture) in Nehbandan Executive Systems

    OpenAIRE

    Mohammad Ziaadini; Marzieh Hashemi

    2013-01-01

    This research basically aims to study the relationship between rate of organizational socialization and rate of employees’ conformity (group stress, kind of character, individualism culture and pluralism culture) in Nehbandan executive systems. Statistical society of this research includes 70 newcomer employees in Nehbandan government offices and centers and sample size was regarded equal to statistical society. Instruments of collecting data are two questionnaires of socialization and confor...

  8. Acute effects of high-dose furosemide on residual renal function in CAPD patients

    NARCIS (Netherlands)

    van Olden, Rudolf W.; Guchelaar, Henk-Jan; Struijk, Dirk G.; Krediet, Raymond T.; Arisz, Lambertus

    2003-01-01

    BACKGROUND: High doses of furosemide can increase urine volume in chronic peritoneal dialysis (CAPD) patients. However, no information is available about effects on urinary solute excretion in relation to residual glomerular filtration rate (GFR), urinary furosemide excretion, and peritoneal solute

  9. Clinical characteristics of veterans prescribed high doses of opioid medications for chronic non-cancer pain.

    Science.gov (United States)

    Morasco, Benjamin J; Duckart, Jonathan P; Carr, Thomas P; Deyo, Richard A; Dobscha, Steven K

    2010-12-01

    Little is known about patients prescribed high doses of opioids to treat chronic non-cancer pain, though these patients may be at higher risk for medication-related complications. We describe the prevalence of high-dose opioid use and associated demographic and clinical characteristics among veterans treated in a VA regional healthcare network. Veterans with chronic non-cancer pain prescribed high doses of opioids (≥ 180 mg/day morphine equivalent; n=478) for 90+ consecutive days were compared to two groups with chronic pain: Traditional-dose (5-179 mg/day; n=500) or no opioid (n=500). High-dose opioid use occurred in 2.4% of all chronic pain patients and in 8.2% of all chronic pain patients prescribed opioids long-term. The average dose in the high-dose group was 324.9 (SD=285.1)mg/day. The only significant demographic difference among groups was race (p=0.03) with black veterans less likely to receive high doses. High-dose patients were more likely to have four or more pain diagnoses and the highest rates of medical, psychiatric, and substance use disorders. After controlling for demographic factors and VA facility, neuropathy, low back pain, and nicotine dependence diagnoses were associated with increased likelihood of high-dose prescriptions. High-dose patients frequently did not receive care consistent with treatment guidelines: there was frequent use of short-acting opioids, urine drug screens were administered to only 25.7% of patients in the prior year, and 32.0% received concurrent benzodiazepine prescriptions, which may increase risk for overdose and death. Further study is needed to identify better predictors of high-dose usage, as well as the efficacy and safety of such dosing. Published by Elsevier B.V.

  10. Proposal of a high dose rate brachytherapy model for radiobiology studies in vitro; Proposta de um modelo de braquiterapia de alta taxa de dose para estudos de radiobiologia in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Geraldo, Jony M.; Andrade, Lidia M., E-mail: jony.marques@mariopenna.org.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte (Brazil). Departamento de Fisica; Trindade, Cassia [Hospital Luxemburgo, Belo Horizonte, MG (Brazil); Nogueira, Luciana B. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte (Brazil). Faculdade de Medicina; Furtado, Clascidia A.; Ladeira, Luiz Orlando [Centro de Desenvolvimento da Tecnologia Nuclear (CTDN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2016-07-01

    The aim of this research was to develop an easy and reproducible approach for experimental HDR brachytherapy allowing in vitro irradiation studies based on clinical parameters. An acrylic platform was designed to attach T25 tissue culture flasks and multi-well tissue culture plates as well as kept the catheters in a fixed position during irradiation. CT images were taken and the irradiation was planned for 550cGy dose applied on adherent tumor cells. Dosimetric measurements were done and all relevant uncertainties were taken into account in order to figure out the correct dose range received by the cells. Tumor cells were irradiated two times over an interval of 24h between irradiations. Proof of concepts of this approach was carried out by biological effects analysis using a radioresistant human epidermoid carcinoma A431 cell line. Cellular proliferation and cell cycle phase were assessed by Trypan blue exclusion assay and DNA content analysis by flow cytometry, respectively. This approach allowed uniform dose distribution around the arrangement in all types of tissue culture plastics evaluated. Corrections due to uncertainties were managed. Regarding in vitro assays there was a significant (p<0.05) decreasing of cellular proliferation rate in irradiated cells. Moreover, increased percentage of cells arrested in G2/M phase (32.3 ± 1.5%) were observed for treated group compared with untreated cells. (author)

  11. Proposal of a high dose rate brachytherapy model for in vitro radiobiology studies; Proposta de um modelo de braquiterapia de alta taxa de dose para estudos de radiobiologia in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Geraldo, Jony M.; Nogueira, Luciana B.; Andrade, Lidia M. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil); Trindade, Cassia [Hospital Luxemburgo, Belo Horizonte, MG (Brazil); Furtado, Clascidia A.; Ladeira, Luiz Orlando, E-mail: jony.marques@mariopenna.org.br [Centro de Desenvolvimento da Tecnologia Nuclear (CTDN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2016-07-01

    The aim of this research was to develop an easy and reproducible approach for experimental HDR brachytherapy allowing in vitro irradiation studies based on clinical parameters. An acrylic platform was designed to attach T25 tissue culture flasks and multi-well tissue culture plates as well as kept the catheters in a fixed position during irradiation. CT images were taken and the irradiation was planned for 550cGy dose applied on adherent tumor cells. Dosimetric measurements were done and all relevant uncertainties were taken into account in order to figure out the correct dose range received by the cells. Tumor cells were irradiated two times over an interval of 24h between irradiations. Proof of concepts of this approach was carried out by biological effects analysis using a radioresistant human epidermoid carcinoma A431 cell line. Cellular proliferation and cell cycle phase were assessed by Trypan blue exclusion assay and DNA content analysis by flow cytometry, respectively. This approach allowed uniform dose distribution around the arrangement in all types of tissue culture plastics evaluated. Corrections due to uncertainties were managed. Regarding in vitro assays there was a significant (p<0.05) decreasing of cellular proliferation rate in irradiated cells. Moreover, increased percentage of cells arrested in G2/M phase (32.3 ± 1.5%) were observed for treated group compared with untreated cells. (author)

  12. Conformational Changes Represent the Rate-Limiting Step in the Transport Cycle of Maize SUCROSE TRANSPORTER1[C][W

    Science.gov (United States)

    Derrer, Carmen; Wittek, Anke; Bamberg, Ernst; Carpaneto, Armando; Dreyer, Ingo; Geiger, Dietmar

    2013-01-01

    Proton-driven Suc transporters allow phloem cells of higher plants to accumulate Suc to more than 1 M, which is up to ∼1000-fold higher than in the surrounding extracellular space. The carrier protein can accomplish this task only because proton and Suc transport are tightly coupled. This study provides insights into this coupling by resolving the first step in the transport cycle of the Suc transporter SUT1 from maize (Zea mays). Voltage clamp fluorometry measurements combining electrophysiological techniques with fluorescence-based methods enable the visualization of conformational changes of SUT1 expressed in Xenopus laevis oocytes. Using the Suc derivate sucralose, binding of which hinders conformational changes of SUT1, the association of protons to the carrier could be dissected from transport-associated movements of the protein. These combined approaches enabled us to resolve the binding of protons to the carrier and its interrelationship with the alternating movement of the protein. The data indicate that the rate-limiting step of the reaction cycle is determined by the accessibility of the proton binding site. This, in turn, is determined by the conformational change of the SUT1 protein, alternately exposing the binding pockets to the inward and to the outward face of the membrane. PMID:23964025

  13. Imaging method for monitoring delivery of high dose rate brachytherapy

    Science.gov (United States)

    Weisenberger, Andrew G; Majewski, Stanislaw

    2012-10-23

    A method for in-situ monitoring both the balloon/cavity and the radioactive source in brachytherapy treatment utilizing using at least one pair of miniature gamma cameras to acquire separate images of: 1) the radioactive source as it is moved in the tumor volume during brachytherapy; and 2) a relatively low intensity radiation source produced by either an injected radiopharmaceutical rendering cancerous tissue visible or from a radioactive solution filling a balloon surgically implanted into the cavity formed by the surgical resection of a tumor.

  14. Rates and equilibrium constants of the ligand-induced conformational transition of an HCN ion channel protein domain determined by DEER spectroscopy.

    Science.gov (United States)

    Collauto, Alberto; DeBerg, Hannah A; Kaufmann, Royi; Zagotta, William N; Stoll, Stefan; Goldfarb, Daniella

    2017-06-14

    Ligand binding can induce significant conformational changes in proteins. The mechanism of this process couples equilibria associated with the ligand binding event and the conformational change. Here we show that by combining the application of W-band double electron-electron resonance (DEER) spectroscopy with microfluidic rapid freeze quench (μRFQ) it is possible to resolve these processes and obtain both equilibrium constants and reaction rates. We studied the conformational transition of the nitroxide labeled, isolated carboxy-terminal cyclic-nucleotide binding domain (CNBD) of the HCN2 ion channel upon binding of the ligand 3',5'-cyclic adenosine monophosphate (cAMP). Using model-based global analysis, the time-resolved data of the μRFQ DEER experiments directly provide fractional populations of the open and closed conformations as a function of time. We modeled the ligand-induced conformational change in the protein using a four-state model: apo/open (AO), apo/closed (AC), bound/open (BO), bound/closed (BC). These species interconvert according to AC + L ⇌ AO + L ⇌ BO ⇌ BC. By analyzing the concentration dependence of the relative contributions of the closed and open conformations at equilibrium, we estimated the equilibrium constants for the two conformational equilibria and the open-state ligand dissociation constant. Analysis of the time-resolved μRFQ DEER data gave estimates for the intrinsic rates of ligand binding and unbinding as well as the rates of the conformational change. This demonstrates that DEER can quantitatively resolve both the thermodynamics and the kinetics of ligand binding and the associated conformational change.

  15. Análises de protocolos de braquiterapia, por alta taxa de dose, do controle de qualidade de alguns serviços locais, baseados no TG40, TG56 e ARCAL XXX Analysis of the high dose rate brachytherapy protocols of quality assurance programs of some local services, based on TG40, TG56 and ARCAL XXX.

    Directory of Open Access Journals (Sweden)

    Carmen S. Guzmán Calcina

    2001-08-01

    Full Text Available A braquiterapia por alta taxa de dose está recebendo atenção considerável na maioria dos países. Por isso, nos serviços que utilizam este equipamento exige-se que o desenvolvimento de um programa de controle de qualidade seja cada vez mais rigoroso, para garantir não apenas a segurança aos pacientes, mas também aos operadores e demais envolvidos. Este trabalho tem por objetivos fazer um levantamento dos tipos de testes para um equipamento de braquiterapia por alta taxa de dose, propostos pelos protocolos oficiais publicados (TG40, TG56 e ARCAL XXX e avaliar os tipos de testes que atualmente são realizados por alguns serviços de radioterapia, comparando-os com aqueles apresentados nos protocolos citados. Das análises feitas, observou-se que: a quanto aos protocolos oficiais, o TG56 é mais completo que o TG40 e o ARCAL XXX; b quanto às instituições analisadas, estas em geral se basearam no TG56 para elaborar seus próprios protocolos, os quais demonstraram ter também concordância com os outros já citados. Nestes protocolos, a inexistência dos testes anuais foi notada, o que pode ser explicado por sua aparição nas freqüências trimestral e semestral. Do produto deste estudo são apresentadas tabelas dos tipos de testes com suas respectivas freqüências de utilização, das quais um protocolo pode ser inferido para auxiliar na implementação, pelo menos, dos tipos de testes de controle de qualidade básicos e indispensáveis para o equipamento, garantindo, assim, um tratamento adequado aos pacientes e uma melhor segurança ao pessoal envolvido e, conseqüentemente, assegurando a garantia de qualidade na braquiterapia por alta taxa de dose.High dose rate brachytherapy has been increasingly recognized in most countries, and radiotherapy services using this equipment are encouraged to have a very efficient quality assurance program to ensure protection for patients, workers and other personnel involved. The objective of this

  16. Acute renal failure in high dose carboplatin chemotherapy

    NARCIS (Netherlands)

    Frenkel, J.; Kool, G.; de Kraker, J.

    1995-01-01

    Carboplatin has been reported to cause acute renal failure when administered in high doses to adult patients. We report a 4 1/2-year-old girl who was treated with high-dose carboplatin for metastatic parameningeal embryonal rhabdomyosarcoma. Acute renal failure developed followed by a slow partial

  17. Conformance contrast testing between rates of pulmonary tuberculosis in Ecuadorian border areas

    Directory of Open Access Journals (Sweden)

    Claudia Ortiz-Rico

    2015-11-01

    Full Text Available Objective. To estimate rates of cases of respiratory symptomatic subjects and the incidence rate of pulmonary tuberculosis in two border areas of Ecuador, and contrast them with official figures. Materials and methods. Cross-sectional survey in the southeastern (SEBA, and the Andean southern Ecuadorian border areas (ASBA, which were conducted, respectively, in 1 598 and 2 419 persons aged over 15 years recruited over periods of three weeks. In identified respiratory symptomatic cases, a sputum sample was taken for smear testing. The results (odds ratios and their respective 95% confidence intervals, were compared with local and national official figures using maximum likelihood contrasts. Results. The rates of respiratory symptomatic subjects (7.7% and 5.9% in the SEBA, and ASBA, respectively and of pulmonary tuberculosis (cumulative incidence rates of 125 and 140 per 100 000 inhabitants, in the same order were significantly greater than the official figures (of 0.98 and 0.99% for respiratory symptomatic subjects in the SEBA and ASBA, respectively; and of 38.23 per 100 000 inhabitants for pulmonary tuberculosis in Ecuador as a whole (p<0.001. Conclusion. It is necessary to reinforce both active case finding for respiratory symptomatic subject cases, and epidemiological surveillance of pulmonary tuberculosis in Ecuadorian border regions.

  18. Rectal dose-volume constraints in high-dose radiotherapy of localized prostate cancer.

    Science.gov (United States)

    Fiorino, Claudio; Sanguineti, Giuseppe; Cozzarini, Cesare; Fellin, Gianni; Foppiano, Franca; Menegotti, Loris; Piazzolla, Anna; Vavassori, Vittorio; Valdagni, Riccardo

    2003-11-15

    To investigate the relationship between rectal bleeding and dosimetric-clinical parameters in patients receiving three-dimensional conformal radiotherapy (3D-CRT) for localized prostate cancer. In a retrospective national study (AIROPROS01-01, AIRO: Associazione Italiana Radioterapia Oncologica), planning/clinical data for 245 consecutive patients with stage T1-4N0-x prostate carcinoma who underwent 3D-CRT to 70-78 Gy (ICRU point) were pooled from four Italian institutions. The correlation between late rectal bleeding and rectal dose-volume data (the percentage of rectum receiving more than 50, 55, 60, 65, 70, and 75 Gy [V(50-70)]) and other dosimetric and clinical parameters were investigated in univariate (log-rank) and multivariate (Cox regression model) analyses. Median follow-up was 2 years. Twenty-three patients were scored as late bleeders according to a modified RTOG definition (Grade 2: 16; Grade 3: 7); the actuarial 2-year rate was 9.2%. Excepting V75, all median and third quartile V(50-70) values were found to be significantly correlated with late bleeding at univariate analysis. The smallest p value was seen for V(50) below/above the third quartile value (66%). The V70 (cut-off value: 30%) was found to be also predictive for late bleeding. In the high-dose subgroup (74-78 Gy), Grade 3 bleeding was highly correlated with this constraint. The predictive value of both V(50) and V(70) was confirmed by multivariate analyses. The present article provides evidence for correlation between rectal DVH parameters and late rectal bleeding in patients treated with curative intent with 3D-CRT. To keep the rate of moderate/severe rectal bleeding below 5-10%, it seems advisable to limit V(50) to 60-65%, V(60) to 45-50%, and V70 to 25-30%.

  19. Protease-sensitive conformers in broad spectrum of distinct PrPSc structures in sporadic Creutzfeldt-Jakob disease are indicator of progression rate.

    Science.gov (United States)

    Kim, Chae; Haldiman, Tracy; Cohen, Yvonne; Chen, Wei; Blevins, Janis; Sy, Man-Sun; Cohen, Mark; Safar, Jiri G

    2011-09-01

    The origin, range, and structure of prions causing the most common human prion disease, sporadic Creutzfeldt-Jakob disease (sCJD), are largely unknown. To investigate the molecular mechanism responsible for the broad phenotypic variability of sCJD, we analyzed the conformational characteristics of protease-sensitive and protease-resistant fractions of the pathogenic prion protein (PrP(Sc)) using novel conformational methods derived from a conformation-dependent immunoassay (CDI). In 46 brains of patients homozygous for polymorphisms in the PRNP gene and exhibiting either Type 1 or Type 2 western blot pattern of the PrP(Sc), we identified an extensive array of PrP(Sc) structures that differ in protease sensitivity, display of critical domains, and conformational stability. Surprisingly, in sCJD cases homozygous for methionine or valine at codon 129 of the PRNP gene, the concentration and stability of protease-sensitive conformers of PrP(Sc) correlated with progression rate of the disease. These data indicate that sCJD brains exhibit a wide spectrum of PrP(Sc) structural states, and accordingly argue for a broad spectrum of prion strains coding for different phenotypes. The link between disease duration, levels, and stability of protease-sensitive conformers of PrP(Sc) suggests that these conformers play an important role in the pathogenesis of sCJD.

  20. Protease-sensitive conformers in broad spectrum of distinct PrPSc structures in sporadic Creutzfeldt-Jakob disease are indicator of progression rate.

    Directory of Open Access Journals (Sweden)

    Chae Kim

    2011-09-01

    Full Text Available The origin, range, and structure of prions causing the most common human prion disease, sporadic Creutzfeldt-Jakob disease (sCJD, are largely unknown. To investigate the molecular mechanism responsible for the broad phenotypic variability of sCJD, we analyzed the conformational characteristics of protease-sensitive and protease-resistant fractions of the pathogenic prion protein (PrP(Sc using novel conformational methods derived from a conformation-dependent immunoassay (CDI. In 46 brains of patients homozygous for polymorphisms in the PRNP gene and exhibiting either Type 1 or Type 2 western blot pattern of the PrP(Sc, we identified an extensive array of PrP(Sc structures that differ in protease sensitivity, display of critical domains, and conformational stability. Surprisingly, in sCJD cases homozygous for methionine or valine at codon 129 of the PRNP gene, the concentration and stability of protease-sensitive conformers of PrP(Sc correlated with progression rate of the disease. These data indicate that sCJD brains exhibit a wide spectrum of PrP(Sc structural states, and accordingly argue for a broad spectrum of prion strains coding for different phenotypes. The link between disease duration, levels, and stability of protease-sensitive conformers of PrP(Sc suggests that these conformers play an important role in the pathogenesis of sCJD.

  1. Radiolesão vascular como efeito deletério da braquiterapia intra-arterial com dose elevada de Samário-153 em coelhos hipercolesterolêmicos Vascular radiolesion as a deleterious effect of high-dose-rate intraarterial brachytherapy with Samarium-153 in hypercholesterolemic rabbits

    Directory of Open Access Journals (Sweden)

    Dalton Bertolim Précoma

    2006-10-01

    Full Text Available OBJETIVO: Este estudo tem por objetivo avaliar as alterações vasculares morfológicas e morfométricas induzidas pela braquiterapia com Samário-153 (153 Sm em coelhos hipercolesterolêmicos, com doses elevadas. MÉTODOS: Foram analisados 43 coelhos hipercolesterolêmicos, brancos, da raça New Zealand, e o total de 86 artérias ilíacas submetidas a lesão por balão de angioplastia. Divididos em três grupos: dois (GI irradiados com as doses de 15Gy (n=14 e 60Gy (n=36 e um grupo controle (n=36. Foram realizadas avaliação histológica morfométrica e análise histológica qualitativa para análise tecidual. RESULTADOS: Foram observadas uma redução significativa da neoproliferação intimal (NPI no GI 15 Gy (pOBJECTIVE: This study was designed to evaluate vascular morphological and morphometric changes induced by brachytherapy with samarium-153 (Sm-153 at high doses in hypercholesterolemic rabbits. METHODS: Forty-three New Zealand White hypercholesterolemic rabbits were analyzed, and the total of 86 iliac arteries underwent balloon angioplasty injury. The rabbits were divided into three different groups: two irradiation groups (IG assigned to 15 Gy (n=14 and 60 Gy (n=36 irradiation doses, respectively, and a control group (n = 36. Histomorphometric and qualitative histological analyses were performed for tissue evaluation. RESULTS: Significant reductions were found in neointimal proliferation (NIP (p< 0.0001, media area (MA (p<0.0001 and percent stenosis (p<0.0001 in the 15-Gy IG, compared to the other groups. The 60-Gy IG had the higher rate of NIP, increase in media and vessel areas (VA and percent stenosis. The 60-Gy IG also showed the greatest number of xanthomatous cells (60-Gy IG: 86.11% and 15-Gy IG: 14.29%, p<0.0001 and the highest amount of hyaline amorphous tissue (60-Gy IG:58.33% and 15-Gy IG:0%, p=0.0001 and vascular proliferation (60-Gy IG:30.56% and 15-Gy IG:0%, p=0.0221. No statistically significant differences were found

  2. A randomized trial of high-dose vitamin D2 in relapsing-remitting multiple sclerosis.

    Science.gov (United States)

    Stein, M S; Liu, Y; Gray, O M; Baker, J E; Kolbe, S C; Ditchfield, M R; Egan, G F; Mitchell, P J; Harrison, L C; Butzkueven, H; Kilpatrick, T J

    2011-10-25

    Higher latitude, lower ultraviolet exposure, and lower serum 25-hydroxyvitamin D (25OHD) correlate with higher multiple sclerosis (MS) prevalence, relapse rate, and mortality. We therefore evaluated the effects of high-dose vitamin D2 (D2) in MS. Adults with clinically active relapsing-remitting MS (RRMS) were randomized to 6 months' double-blind placebo-controlled high-dose vitamin D2, 6,000 IU capsules, dose adjusted empirically aiming for a serum 25OHD 130-175 nM. All received daily low-dose (1,000 IU) D2 to prevent deficiency. Brain MRIs were performed at baseline, 4, 5, and 6 months. Primary endpoints were the cumulative number of new gadolinium-enhancing lesions and change in the total volume of T2 lesions. Secondary endpoints were Expanded Disability Status Scale (EDSS) score and relapses. Twenty-three people were randomized, of whom 19 were on established interferon or glatiramer acetate (Copaxone) treatment. Median 25OHD rose from 54 to 69 nM (low-dose D2) vs 59 to 120 nM (high-dose D2) (p = 0.002). No significant treatment differences were detected in the primary MRI endpoints. Exit EDSS, after adjustment for entry EDSS, was higher following high-dose D2 than following low-dose D2 (p = 0.05). There were 4 relapses with high-dose D2 vs none with low-dose D2 (p = 0.04). We did not find a therapeutic advantage in RRMS for high-dose D2 over low-dose D2 supplementation. This study provides Class I evidence that high-dose vitamin D2 (targeting 25OHD 130-175 nM), compared to low-dose supplementation (1,000 IU/d), was not effective in reducing MRI lesions in patients with RRMS.

  3. High-dose insulin therapy in beta-blocker and calcium channel-blocker poisoning.

    Science.gov (United States)

    Engebretsen, Kristin M; Kaczmarek, Kathleen M; Morgan, Jenifer; Holger, Joel S

    2011-04-01

    INTRODUCTION. High-dose insulin therapy, along with glucose supplementation, has emerged as an effective treatment for severe beta-blocker and calcium channel-blocker poisoning. We review the experimental data and clinical experience that suggests high-dose insulin is superior to conventional therapies for these poisonings. PRESENTATION AND GENERAL MANAGEMENT. Hypotension, bradycardia, decreased systemic vascular resistance (SVR), and cardiogenic shock are characteristic features of beta-blocker and calcium-channel blocker poisoning. Initial treatment is primarily supportive and includes saline fluid resuscitation which is essential to correct vasodilation and low cardiac filling pressures. Conventional therapies such as atropine, glucagon and calcium often fail to improve hemodynamic status in severely poisoned patients. Catecholamines can increase blood pressure and heart rate, but they also increase SVR which may result in decreases in cardiac output and perfusion of vascular beds. The increased myocardial oxygen demand that results from catecholamines and vasopressors may be deleterious in the setting of hypotension and decreased coronary perfusion. METHODS. The Medline, Embase, Toxnet, and Google Scholar databases were searched for the years 1975-2010 using the terms: high-dose insulin, hyperinsulinemia-euglycemia, beta-blocker, calcium-channel blocker, toxicology, poisoning, antidote, toxin-induced cardiovascular shock, and overdose. In addition, a manual search of the Abstracts of the North American Congress of Clinical Toxicology and the Congress of the European Association of Poisons Centres and Clinical Toxicologists published in Clinical Toxicology for the years 1996-2010 was undertaken. These searches identified 485 articles of which 72 were considered relevant. MECHANISMS OF HIGH-DOSE INSULIN BENEFIT. There are three main mechanisms of benefit: increased inotropy, increased intracellular glucose transport, and vascular dilatation. EFFICACY OF HIGH-DOSE

  4. Irreversible encephalopathy after treatment with high-dose intravenous metronidazole.

    NARCIS (Netherlands)

    Groothoff, M.V.R.; Hofmeijer, J.; Sikma, M.A.; Meulenbelt, J.

    2010-01-01

    BACKGROUND: Encephalopathy associated with metronidazole is rare and, in most cases, reversible following discontinuation. OBJECTIVE: We describe a case of fatal encephalopathy after treatment with high-dose intravenous metronidazole and the potential causes of the irreversibility. CASE SUMMARY: A

  5. Irreversible Encephalopathy After Treatment With High-Dose Intravenous Metronidazole

    NARCIS (Netherlands)

    Groothoff, Miriam V. R.; Hofmeijer, Jannette; Sikma, Maaike A.; Meulenbelt, Jan

    Background: Encephalopathy associated with metronidazole is rare and, in most cases, reversible following discontinuation. Objective: We describe a case of fatal encephalopathy after treatment with high-dose intravenous metronidazole and the potential causes of the irreversibility. Case summary: A

  6. High-dose dosimetry using natural silicate minerals

    Energy Technology Data Exchange (ETDEWEB)

    Carmo, Lucas S. do; Mendes, Leticia, E-mail: isatiro@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Watanabe, Shigueo; Rao, Gundu; Lucas, Natasha; Sato, Karina, E-mail: lacifid@if.usp.br [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Instituto de Fisica. Departamento de Fisica Nuclear; Barbosa, Renata F., E-mail: profcelta@hotmail.com [Universidade Federal de Sao Paulo (UNIFESP), Santos, SP (Brazil). Departamento de Ciencias do Mar

    2015-07-01

    In the present study, certain natural silicate minerals such as aquamarine (AB), morganite (PB), goshenite (WB), white jadeite (JW), green jadeite (JG), pink tourmaline (PT) and two varieties of jadeite-like quartz, denoted here by JQ1 and JQ2, were investigated using the thermoluminescence technique to evaluate their potential for use as very-high- and high-dose dosimeters. These minerals respond to high doses of γ-rays of up to 1000 kGy and often to very high doses of up to 3000 kGy. The TL response of these minerals may be considered to be satisfactory for applications in high-dose dosimetry. Investigations of electron paramagnetic resonance and optically stimulated luminescence dosimetry are in progress. (author)

  7. Relative safety profiles of high dose statin regimens

    Directory of Open Access Journals (Sweden)

    Carlos Escobar

    2008-06-01

    Full Text Available Carlos Escobar, Rocio Echarri, Vivencio BarriosDepartment of Cardiology, Hospital Ramón y Cajal, Madrid, SpainAbstract: Recent clinical trials recommend achieving a low-density lipoprotein cholesterol level of <100 mg/dl in high-risk and <70 mg/dl in very high risk patients. To attain these goals, however, many patients will need statins at high doses. The most frequent side effects related to the use of statins, myopathy, rhabdomyolysis, and increased levels of transaminases, are unusual. Although low and moderate doses show a favourable profile, there is concern about the tolerability of higher doses. During recent years, numerous trials to analyze the efficacy and tolerability of high doses of statins have been published. This paper updates the published data on the safety of statins at high doses.Keywords: statins, high doses, tolerability, liver, muscle

  8. Adjuvant radiation therapy for the treatment of endometrial cancer: experience with combination of external radiation therapy and high-dose rate brachytherapy; Radioterapia adjuvante no tratamento do cancer de endometrio: experiencia com a associacao de radioterapia externa e braquiterapia de alta taxa de dose

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Michael Jenwei; Novaes, Paulo Eduardo Ribeiro Soares; Pellizzon, Antonio Cassio de Assis; Ferrigno, Robson; Fogaroli, Ricardo Cesar; Maia, Maria Aparecida Conte; Salvajoli, Joao Victor [Hospital do Cancer A.C. Camargo, Sao Paulo, SP (Brazil). Dept. de Radioterapia]. E-mail: michael.chen@ig.com.br; Nishimoto, Ines Nobuko [Hospital do Cancer A.C. Camargo, Sao Paulo, SP (Brazil). Centro de Estudos

    2005-12-01

    Objective: To review the results of adjuvant external beam radiation therapy (EBRT) combined with high-dose rate brachytherapy (HDR-BT) for the treatment of endometrial carcinoma. Materials and methods: We retrospectively evaluated 141 patients treated with EBRT and HDR-BT after surgery between January 1993 and January 2001. EBRT was performed with a median dose of 45 Gy, and HDR-BT was performed with a median dose of 24 Gy, with four weekly insertions of 6 Gy. The median age of the patients was 63 years and the disease stage distribution was: CS I (FIGO), 52.4%; CS II, 13.5%; CS III, 29.8%; CS IV, 4.3%. Results: With a median follow-up of 53.7 months, the disease free survival (DFS) at five years was: CS I, 88.0%; CS II, 70.8%; CS III, 55.1%; CS IV, 50.0% (p = 0.0003). Global survival after five years was: CS I, 79.6%; CS II, 74.0%; CS III, 53.6%; CS IV, 100.0% (p = 0.0062). Factors affecting the DFS were histological grade and serous-papillary histology. Recurrence of the disease was observed in 33 cases, 13 (9.2%) of these occurred in the pelvis, vagina or vaginal vault. EBRT + HDR-BT of the vaginal vault allowed disease control in 90.8% of the cases. Conclusion: Radiation therapy is essential for loco-regional control of endometrial cancer and can achieve excellent cure rates in the initial stages. In more advanced stages, therapeutic failure frequently appears as distant metastases suggesting the need for complementary systemic therapy using new treatment modalities, particularly chemotherapy. (author)

  9. Dehydration-induced conformational changes of poly-L-lysine as influenced by drying rate and carbohydrates.

    NARCIS (Netherlands)

    Wolkers, W.F.; Kilsdonk, van M.G.; Hoekstra, F.A.

    1998-01-01

    The conformation of hydrated and air-dried poly-L-lysine in thin films was studied using Fourier transform IR spectroscopy in the amide-I region. Hydrated poly-L-lysine has a random coil conformation. Upon slow drying of small droplets of the polypeptide solution over a period of several hours, an

  10. Dosimetric comparison of (192)Ir high-dose-rate brachytherapy vs. 50 kV x-rays as techniques for breast intraoperative radiation therapy: conceptual development of image-guided intraoperative brachytherapy using a multilumen balloon applicator and in-room CT imaging.

    Science.gov (United States)

    Jones, Ryan; Libby, Bruce; Showalter, Shayna L; Brenin, David R; Wilson, David D; Schroen, Anneke; Morris, Monica; Reardon, Kelli A; Morrison, John; Showalter, Timothy N

    2014-01-01

    At our institution, the availability of a shielded procedure room with in-room CT-on-rails imaging allows for the exploration of a high-dose-rate (HDR) brachytherapy approach for breast intraoperative radiation therapy (IORT). We hypothesize that HDR brachytherapy will permit a higher prescription dose without increasing toxicity. In this study, we compare the dosimetry of intraoperative HDR brachytherapy, using multilumen balloon applicator, to IORT with a 50 kV source and then select a prescription dose for a subsequent clinical trial. The CT scans of 14 patients who had previously received multilumen balloon-based breast brachytherapy were replanned to a standard prescription to the target volume. The same 14 cases were planned to the specifications of a 50 kV x-ray system. Uniform volume optimization and prescription doses were used to permit direct comparisons. All plans were evaluated for the dose homogeneity index, tumor coverage, and dose to normal tissues, including skin, ribs, and heart (for left breast plans). The HDR brachytherapy plans were superior to 50 kV superficial photon plans for IORT in all dosimetric parameters except for the heart and rib dosimetric parameters. Prescription dose of 12.5 Gy to the planning target volume for evaluation yielded a dose to 95 percent of the balloon surface of 19.7 Gy. Image-guided HDR intraoperative brachytherapy with a multilumen balloon applicator provides superior target volume coverage compared with 50 kV photons, while maintaining doses within tolerance limits for normal tissues. An ongoing prospective clinical trial will evaluate the safety and feasibility of this technique. Copyright © 2014 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  11. "Time sequential high dose of Cytarabine in acute myelocytic leukemia "

    Directory of Open Access Journals (Sweden)

    Ghavamzadeh A

    2003-05-01

    Full Text Available Given preliminary evidence of timed, sequential chemotherapy of high dose cytosine arabinoside the current study was initiated to assess the side effects and efficacy of this regimen in patients with newly acute myelocytic leukemia (AML. Nineteen adults who referred to Hematology-Oncology and Bone Marrow Transplantation (BMT research center of Tehran University of Medical Sciences were enrolled in a trial from Aug 1999 to Nov 2000. All patients had a Karnofski classification above 60%. At this time induction therapy consisted of daunorubicin or idarubicin given at a dose of 60 mg/m² and 12 mg/m² IV respectively on days 1-3, and cytarabine (Ara-C 100 mg/m² intravenously by continuous infusion on days 1-7, followed by Ara-C 1000 mg/m² given on day 8-10 every 12 hours by IV infusion. Consolidation therapy started after 35th day. Of 19 fully evaluable patients, 10 patients achieved a complete remission, whereas 36.6% patients succumbed to death due to regeneration failure. The clinical data show that the overall survival rate from diagnosis 55.5% (95% CI, 30.8-78.5 at 6 months for the entire cohort of the patients. Disease free survival is also 50% (95% CI, 26-74. Mean duration of death due to treatment was 20 days (range 17-29 after beginning the regimen. Presenting WBC counts, French-American-British (FAB classification, sex and age were not useful prognostic variables. Fever, diarrhea, nausea and vomiting and GI hemorrhage were seen in 19, 6, 4, 7 patients respectively. It seems the 3+7+3 regimen is a promising approach for the AML patients regarding to high complete remission rate, but more supportive care should be considered. Furthermore any, benefit in long-term outcome can’t be determined regardless to the choice of post remission therapy (e.g., GCSF, appropriate antibiotics and etc.

  12. Tolerance of the Brachial Plexus to High-Dose Reirradiation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Allen M., E-mail: achen5@kumc.edu; Yoshizaki, Taeko; Velez, Maria A.; Mikaeilian, Argin G.; Hsu, Sophia; Cao, Minsong

    2017-05-01

    Purpose: To study the tolerance of the brachial plexus to high doses of radiation exceeding historically accepted limits by analyzing human subjects treated with reirradiation for recurrent tumors of the head and neck. Methods and Materials: Data from 43 patients who were confirmed to have received overlapping dose to the brachial plexus after review of radiation treatment plans from the initial and reirradiation courses were used to model the tolerance of this normal tissue structure. A standardized instrument for symptoms of neuropathy believed to be related to brachial plexus injury was utilized to screen for toxicity. Cumulative dose was calculated by fusing the initial dose distributions onto the reirradiation plan, thereby creating a composite plan via deformable image registration. The median elapsed time from the initial course of radiation therapy to reirradiation was 24 months (range, 3-144 months). Results: The dominant complaints among patients with symptoms were ipsilateral pain (54%), numbness/tingling (31%), and motor weakness and/or difficulty with manual dexterity (15%). The cumulative maximum dose (Dmax) received by the brachial plexus ranged from 60.5 Gy to 150.1 Gy (median, 95.0 Gy). The cumulative mean (Dmean) dose ranged from 20.2 Gy to 111.5 Gy (median, 63.8 Gy). The 1-year freedom from brachial plexus–related neuropathy was 67% and 86% for subjects with a cumulative Dmax greater than and less than 95.0 Gy, respectively (P=.05). The 1-year complication-free rate was 66% and 87%, for those reirradiated within and after 2 years from the initial course, respectively (P=.06). Conclusion: The development of brachial plexus–related symptoms was less than expected owing to repair kinetics and to the relatively short survival of the subject population. Time-dose factors were demonstrated to be predictive of complications.

  13. Tolerance of the Brachial Plexus to High-Dose Reirradiation.

    Science.gov (United States)

    Chen, Allen M; Yoshizaki, Taeko; Velez, Maria A; Mikaeilian, Argin G; Hsu, Sophia; Cao, Minsong

    2017-05-01

    To study the tolerance of the brachial plexus to high doses of radiation exceeding historically accepted limits by analyzing human subjects treated with reirradiation for recurrent tumors of the head and neck. Data from 43 patients who were confirmed to have received overlapping dose to the brachial plexus after review of radiation treatment plans from the initial and reirradiation courses were used to model the tolerance of this normal tissue structure. A standardized instrument for symptoms of neuropathy believed to be related to brachial plexus injury was utilized to screen for toxicity. Cumulative dose was calculated by fusing the initial dose distributions onto the reirradiation plan, thereby creating a composite plan via deformable image registration. The median elapsed time from the initial course of radiation therapy to reirradiation was 24 months (range, 3-144 months). The dominant complaints among patients with symptoms were ipsilateral pain (54%), numbness/tingling (31%), and motor weakness and/or difficulty with manual dexterity (15%). The cumulative maximum dose (Dmax) received by the brachial plexus ranged from 60.5 Gy to 150.1 Gy (median, 95.0 Gy). The cumulative mean (Dmean) dose ranged from 20.2 Gy to 111.5 Gy (median, 63.8 Gy). The 1-year freedom from brachial plexus-related neuropathy was 67% and 86% for subjects with a cumulative Dmax greater than and less than 95.0 Gy, respectively (P=.05). The 1-year complication-free rate was 66% and 87%, for those reirradiated within and after 2 years from the initial course, respectively (P=.06). The development of brachial plexus-related symptoms was less than expected owing to repair kinetics and to the relatively short survival of the subject population. Time-dose factors were demonstrated to be predictive of complications. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Pulsed high-dose dexamethasone versus standard prednisolone treatment for chronic inflammatory demyelinating polyradiculoneuropathy (PREDICT study): a double-blind, randomised, controlled trial

    NARCIS (Netherlands)

    van Schaik, Ivo N.; Eftimov, Filip; van Doorn, Pieter A.; Brusse, Esther; van den Berg, Leonard H.; van der Pol, W. Ludo; Faber, Catharina G.; van Oostrom, Joost Ch; Vogels, Oscar Jm; Hadden, Rob Dm; Kleine, Bert U.; van Norden, Anouk Gw; Verschuuren, Jan Jgm; Dijkgraaf, Marcel Gw; Vermeulen, Marinus

    2010-01-01

    Background Pulsed high-dose dexamethasone induced long-lasting remission in patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) in a pilot study. The PREDICT study aimed to compare remission rates in patients with CIDP treated with high-dose dexamethasone with rates in

  15. A PROSPECTIVE RANDOMIZED TRIAL COMPARING SEQUENTIAL GANCICLOVIR-HIGH DOSE ACYCLOVIR TO HIGH DOSE ACYCLOVIR FOR PREVENTION OF CYTOMEGALOVIRUS DISEASE IN ADULT LIVER TRANSPLANT RECIPIENTS

    Science.gov (United States)

    Martin, Maureen; Mañez, Rafael; Linden, Peter; Estores, David; Torre-Cisneros, Julian; Kusne, Shimon; Ondick, Linnea; Ptachcinski, Richard; Irish, William; Kisor, David; Felser, Ilene; Rinaldo, Charles; Stieber, Andrei; Fung, John; Ho, Monto; Simmons, Richard; Starzl, Thomas

    2010-01-01

    Cytomegalovirus disease is an important cause of morbidity following liver transplantation. To date there has not been an effective prophylaxis for CMV disease after liver transplantation. One hundred forty-three patients were randomized to receive either high dose oral acyclovir (800 mg 4 times a day) alone for 3 months after transplantation (acyclovir group) or intravenous ganciclovir (5 mg/kg twice a day) for 14 days followed by high dose oral acyclovir to complete a 3-month regimen (ganciclovir group). Of 139 patients available for evaluation, 43 of 71 (61%) patients from the acyclovir group developed CMV infection compared with 16 of 68 (24%) from the ganciclovir group (relative risk, 3.69; 95% confidence interval, 2.07–6.56; Pganciclovir group (relative risk, 5.11; 95% confidence interval, 2.05–12.75; P=0.000l). The median time to onset of CMV infection was 45 days in the acyclovir group compared with 78 days in the ganciclovir group (P=0.004). The median time to onset of CMV disease was 40 days in the acyclovir group compared with 78 days in the ganciclovir patients (P=0.02). With respect to primary CMV infection, there was no difference in the rates in the 2 groups, but tissue invasive disease and recurrent CMV disease were less frequent in the ganciclovir group. It is concluded that a course of 2 weeks of ganciclovir immediately after transplantation followed by high dose oral acyclovir for 10 weeks is superior to a 12-week course of high dose oral acyclovir alone for prevention of both CMV infection and CMV disease after liver transplantation. However, the lack of significant effect in seronegative recipients who received grafts from seropositive donors suggests that other strategies are needed to prevent CMV infection in this high risk population. PMID:7940710

  16. High-dose intravenous vancomycin therapy and the risk of nephrotoxicity.

    Science.gov (United States)

    Rostas, Sara E; Kubiak, David W; Calderwood, Michael S

    2014-07-01

    National guidelines recommend higher serum trough concentrations when using vancomycin to treat certain clinical conditions, but there is concern that higher-dose vancomycin therapy causes nephrotoxicity. We evaluated risk factors associated with nephrotoxicity in patients receiving high-dose intravenous vancomycin. This retrospective cohort study evaluated the clinical outcome of 80 hospitalized adult patients with normal baseline renal function who received ≥4 g/d of intravenous vancomycin for ≥48 hours between January 1, 2011, and December 31, 2011. After abstracting clinical risk factors, we used an analysis by methods of best clinical subsets to develop a multivariable model predicting nephrotoxicity in patients receiving high-dose vancomycin. The overall rate of nephrotoxicity in the study population was 6%. Trough concentrations >20 mg/L were identified in a similar proportion of patients who did and did not develop nephrotoxicity. Patients who developed nephrotoxicity trended toward having a lower body mass index, higher daily dose, longer duration of therapy, and greater exposure to intravenous contrast and nephrotoxic medications. In a multivariable model, the combination of intravenous contrast and nephrotoxic medications was a significant predictor of nephrotoxicity, and duration of high-dose vancomycin was a significant confounder. Administration of high-dose intravenous vancomycin may have less associated nephrotoxicity than previously reported, although duration of vancomycin therapy may play a role. Concomitant exposure to intravenous contrast and other nephrotoxic medications is a more significant predictor of developing nephrotoxicity than vancomycin dose or trough. Published by EM Inc USA.

  17. Comparison of absorbed dose in the cervix carcinoma therapy by brachytherapy of high dose rate using the conventional planning and Monte Carlo simulation; Comparacao da dose absorvida no tratamento do cancer ginecologico por braquiterapia de alta taxa de dose utilizando o planejamento convencional do tratamento e simulacao de Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Aneli Oliveira da

    2010-07-01

    This study aims to compare the doses received for patients submitted to brachytherapy High Dose Rate (HDR) brachytherapy, a method of treatment of the cervix carcinoma, performed in the planning system PLATO BPS with the doses obtained by Monte Carlo simulation using the radiation transport code MCNP 5 and one female anthropomorphic phantom based on voxel, the FAX. The implementation of HDR brachytherapy treatment for the cervix carcinoma consists of the insertion of an intrauterine probe and an intravaginal probe (ring or ovoid) and then two radiographs are obtained, anteroposterior (AP) and lateral (LAT) to confirm the position of the applicators in the patient and to allow the treatment planning and the determination of the absorbed dose at points of interest: rectum, bladder, sigmoid and point A, which corresponds anatomically to the crossings of the uterine arteries with ureters The absorbed doses obtained with the code MCNP 5, with the exception of the absorbed dose in the rectum and sigmoid for the simulation considering a point source of {sup 192}Ir, are lower than the absorbed doses from PLATO BPS calculations because the MCNP 5 considers the chemical compositions and densities of FAX body, not considering the medium as water. When considering the Monte Carlo simulation for a source with dimensions equal to that used in the brachytherapy irradiator used in this study, the values of calculated absorbed dose to the bladder, to the rectum, to the right point A and to the left point A were respectively lower than those determined by the treatment planning system in 33.29, 5.01, 22.93 and 19.04%. These values are almost all larger than the maximum acceptable deviation between patient planned and administered doses (5 %). With regard to the rectum and bladder, which are organs that must be protected, the present results are in favor of the radiological protection of patients. The point A, that is on the isodose of 100%, used to tumor treatment, the results

  18. High-Dose Intravenous Ribavirin Therapy for Subacute Sclerosing Panencephalitis

    Science.gov (United States)

    Hosoya, Mitsuaki; Shigeta, Shiro; Mori, Shuichi; Tomoda, Akemi; Shiraishi, Seiji; Miike, Teruhisa; Suzuki, Hitoshi

    2001-01-01

    Two patients with subacute sclerosing panencephalitis (SSPE) were treated safely and effectively with high doses of intravenous ribavirin combined with intraventricular alpha interferon. The ribavirin concentrations maintained in the serum and cerebrospinal fluid were higher than those which inhibit SSPE virus replication in vitro and in vivo. PMID:11181386

  19. High-dose chemotherapy regimens for solid tumors

    NARCIS (Netherlands)

    Wall, E. van der; Beijnen, J.H.; Rodenhuis, S.

    1995-01-01

    High-dose chemotherapy with blood progenitor cell transplantation is increasingly recognized as a potentially valuable treatment for breast cancer, germ cell cancer, ovarian cancer and other solid tumors. A variety of cytotoxic drugs, particularly alkylating agents, have been investigated either

  20. Pharmacokinetics of high-dose intravenous melatonin in humans

    DEFF Research Database (Denmark)

    Andersen, Lars P H; Werner, Mads U; Rosenkilde, Mette Marie

    2016-01-01

    This crossover study investigated the pharmacokinetics and adverse effects of high-dose intravenous melatonin. Volunteers participated in 3 identical study sessions, receiving an intravenous bolus of 10 mg melatonin, 100 mg melatonin, and placebo. Blood samples were collected at baseline and 0, 6...

  1. Effect of high dose thiamine therapy on activity and molecular ...

    African Journals Online (AJOL)

    ajl yemi

    2011-11-28

    Nov 28, 2011 ... This study was therefore designed to investigate the effect of high dose thiamine therapy on the activity and molecular aspects of transketolase in Type 2 diabetic patients. Over 100 Type 2 microalbuminuric diabetics were enrolled in a randomized, double blind placebo controlled clinical trial for 6 months.

  2. Unusual complication and successful high-dose chemotherapy ...

    African Journals Online (AJOL)

    Adult Burkitt's lymphoma emerged as an AIDS-defining condition in the 1980s. We describe a case of HIV-associated adult Burkitt's lymphoma diagnosed and treated with high-dose chemotherapy in our institution, complicated by unusual bilateral renal vein tumour thrombi and tumour lysis syndrome. We believe this ...

  3. Bortezomib or high-dose dexamethasone for relapsed multiple myeloma

    NARCIS (Netherlands)

    P.G. Richardson (Paul Gerard); P. Sonneveld (Pieter); M.W. Schuster (Michael); D. Irwin (David); E.A. Stadtmauer (Edward); T. Facon (Thierry); J-L. Harousseau (Jean-Luc); D. Ben-Yehuda (Dina); S. Lonial (Sagar); H. Goldschmidt (Hartmut); D. Reece (Donna); J.F. San Miguel (Jesús Fernando); J. Bladé (Joan); M. Boccadoro (Mario); J. Cavenagh (Jamie); W. Dalton (William); A.L. Boral (Anthony); D.-L. Esseltine (Dixie-Lee); J.B. Porter (Jane); D. Schenkein (David); K.C. Anderson (Kenneth)

    2005-01-01

    textabstractBACKGROUND: This study compared bortezomib with high-dose dexamethasone in patients with relapsed multiple myeloma who had received one to three previous therapies. METHODS: We randomly assigned 669 patients with relapsed myeloma to receive either an intravenous bolus of bortezomib (1.3

  4. Safety and tolerability of high doses of glucocorticoides

    Directory of Open Access Journals (Sweden)

    Rakić Branislava D.

    2016-01-01

    Full Text Available Introduction: Treatment of acute lymphoblastic leukemia includes the use of high doses of glucocorticoides (prednisone and dexamethasone, which significantly increase the success of therapy due to lymphocytolitic effect. The aim: The aim of the study was to determine tolerability of high doses of prednisone and dexamethasone in children with acute lymphoblastic leukemia and the structure and the intensity of adverse effects, occurred after application of these medicines. Subjects and methods: In a prospective study, we analyzed adverse effects of high doses of glucocorticoides in children suffering acute lymphoblastic leukemia treated in the Institute for Child and Youth Health Care of Vojvodina, since December 2010. until October 2014, were analyzed. This study included 18 patients, aged from 2 to 15 years. Results: Hyperglycemia appeared in 89% of patients treated with prednisone and in 61% of patients treated with dexamethasone. In order to control the high blood glucose level (above 10 mmol /L, in 11% of patients insulin was used. Hypertension appeared in 28% patients treated with prednisone and dexamethasone. Antihypertensives were needed for regulation in 17% patients. Hypopotassemia and hypocalcaemia were significantly more expressed after the use of prednisone in comparison to dexamethasone. In 11% of patients, the treatment with dexamethasone caused depressive behavior, followed by agitation. Conclusion: Adverse effects of dexamethasone and prednisone, administered in high doses in children with ALL were known, expected and reversible. Adverse reactions usually disappeared spontaneously or after short-term symptomatic therapy.

  5. Oval pulsed high-dose dexamethasone for myositis

    NARCIS (Netherlands)

    Hoogendijk, JE; Wokke, JHJ; de Visser, M

    To study the short-term effect of oral pulsed high-dose dexamethasone for myositis we treated eight newly diagnosed patients with three 28-day cycles of oral dexamethasone. Primary outcome measures were muscle strength, pain, and serum creatine kinase activity. Sis patients responded. Side effects

  6. Oral pulsed high-dose dexamethasone for myositis

    NARCIS (Netherlands)

    van der Meulen, M. F.; Hoogendijk, J. E.; Wokke, J. H.; de Visser, M.

    2000-01-01

    To study the short-term effect of oral pulsed high-dose dexamethasone for myositis we treated eight newly diagnosed patients with three 28-day cycles of oral dexamethasone. Primary outcome measures were muscle strength, pain, and serum creatine kinase activity. Six patients responded. Side effects

  7. Cirurgia conservadora, radioterapia externa e reforço de dose com braquiterapia de alta taxa de dose: uma nova perspectiva no tratamento de sarcomas de partes moles do adulto Limb-sparing surgery, external beam radiotherapy and boost with high-dose rate brachytherapy: a new perspective for the treatment of soft tissue sarcomas in adults

    Directory of Open Access Journals (Sweden)

    Antonio Cássio Assis Pellizzon

    2002-03-01

    Full Text Available OBJETIVO: Avaliar a influência no controle local de pacientes adultos e portadores de sarcoma de partes moles em extremidades e submetidos a cirurgia conservadora do membro, com braquiterapia de alta taxa de dose (BATD como reforço para a radioterapia externa (RT. MATERIAL E MÉTODOS: Foram avaliados 16 pacientes tratados, de 1993 até 1999. A RT foi utilizada com finalidade pré ou pós-operatória (30--55 Gy e BATD com dose de 18--36 Gy (fx 3--6 Gy BID. Com base no modelo linear quadrático calculou-se a dose efetiva biológica ("biological effective dose" - BED para o tumor e comparou-se seu valor a dados da literatura internacional, que utiliza tratamentos com RT e braquiterapia de baixa taxa de dose (BBTD. RESULTADOS: Os valores médios e medianos da BED para os sarcomas de partes moles foram de 78,5 Gy7 e 80 Gy7. A análise univariada mostrou que a BED para o tumor, quando utilizada BATD, era semelhante ao valor de 83 Gy7 quando utilizada BBTD (p = 0,008. As taxas de controle local, sobrevida livre de doença e sobrevida global atuarial em cinco anos foram de 83,2%, 75% e 93,7%, respectivamente. CONCLUSÕES: A BATD, quando utilizada como método complementar no reforço de dose da RT no tratamento conservador dos sarcomas de partes moles, apresenta taxas de controle local equiparáveis às da literatura internacional; no entanto, estudos com número maior de pacientes e período maior de seguimento são ainda necessários para determinar o verdadeiro potencial da BATD em substituir a BBTD.PURPOSE: To evaluate the influence on local control in adult patients with soft tissue sarcomas of the limbs that underwent limb-sparing surgery and high-dose rate brachytherapy (HDRB in association with teletherapy. MATERIAL AND METHODS: Sixteen patients treated from 1993 to 1999 were reviewed. Teletherapy was used pre- or postoperatively (30--55 Gy in association with HDRB in a dose range of 18--36 Gy (fx 3--6 Gy BID. The linear quadratic model was

  8. Conformal Nets II: Conformal Blocks

    Science.gov (United States)

    Bartels, Arthur; Douglas, Christopher L.; Henriques, André

    2017-08-01

    Conformal nets provide a mathematical formalism for conformal field theory. Associated to a conformal net with finite index, we give a construction of the `bundle of conformal blocks', a representation of the mapping class groupoid of closed topological surfaces into the category of finite-dimensional projective Hilbert spaces. We also construct infinite-dimensional spaces of conformal blocks for topological surfaces with smooth boundary. We prove that the conformal blocks satisfy a factorization formula for gluing surfaces along circles, and an analogous formula for gluing surfaces along intervals. We use this interval factorization property to give a new proof of the modularity of the category of representations of a conformal net.

  9. On line high dose static position monitoring by ionization chamber detector for industrial gamma irradiators

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Ary A. [Universidade Estadual de Londrina-Depto de Fisica, Rodovia Celso Garcia Cid, km 38, 086051-990 Londrina (Brazil); Vieira, Jose M. [Instituto de Pesquisas Energeticas e Nucleares-IPEN/CNEN-SP, Prof. Lineu Prestes, 2242-Cidade Universitaria, 05508-900 Sao Paulo (Brazil); Hamada, Margarida M. [Instituto de Pesquisas Energeticas e Nucleares-IPEN/CNEN-SP, Prof. Lineu Prestes, 2242-Cidade Universitaria, 05508-900 Sao Paulo (Brazil)], E-mail: mmhamada@ipen.br

    2010-04-15

    A 1 cm{sup 3} cylindrical ionization chamber was developed to measure high doses on line during the sample irradiation in static position, in a {sup 60}Co industrial plant. The developed ionization chamber showed to be suitable for use as a dosimeter on line. A good linearity of the detector was found between the dose and the accumulated charge, independently of the different dose rates caused by absorbing materials.

  10. Malignancies in patients treated with high doses of radium-224

    Energy Technology Data Exchange (ETDEWEB)

    Nekolla, E.A. [Federal Office for Radiation Protection (BfS), Neuherberg (Germany); Walsh, L. [Radiobiological Inst., Univ. of Munich (Germany); Schottenhammer, G.; Spiess, H. [Children' s Hospital, Univ. of Munich (Germany)

    2005-07-01

    Several thousand German patients suffering from ankylosing spondylitis, tuberculosis and some other diseases, received multiple injections of the short-lived {alpha}-emitter {sup 224}Ra. The ''Spiess study'' was initiated in the early 1950s to follow the health of 899 persons (278 female, 621 male) who were treated mainly between 1945 and 1955. Most of the high dose patients and nearly all of those treated as children or juveniles (n=217) were included in the study. In June 2003, 152 persons were still alive. The most striking observed health effect, following {sup 224}Ra injections, was a temporal wave of 56 malignant bone tumours with a maximum at about 8 years after exposure which has already been described in several publications. In 2000, a new analysis was performed because an improved dosimetry resulted in modified bone surface doses. The estimated risk coefficient, averaged over all ages at exposure, was found to be in agreement with earlier analyses. However, a statistically significant increase of bone tumour risk with decreasing age at exposure was found. The earlier results, which indicated a reversed protraction factor, were confirmed. A significant excess of non-skeletal solid malignancies has also appeared during the most recent observation decade. In 2004, significant increases of cancer rates were observed for several sites: for breast cancer (31 cases observed vs. 9.1 cases expected), soft tissue malignancies (11 vs. 1.0), thyroid carcinomas (7 vs. 0.9), liver (8 vs. 2.3), kidney (13 vs. 4.6), pancreas (8 vs. 3.9), and bladder cancer (14 vs. 7.7). The 8-fold excess relative risk of mammary cancers in those women exposed as children or juveniles is particularly striking; moreover, 2 cases of breast cancer occurred in men. In 1993, a control group of tuberculosis patients not treated with {sup 224}Ra was established to rule out potential confounding factors - such as chest fluoroscopy - which might bias the breast cancer excess

  11. High-dose secondary calibration laboratory accreditation program

    Energy Technology Data Exchange (ETDEWEB)

    Humphreys, J.C. [National Institute of Standards and Technology, Gaithersburg, MD (United States)

    1993-12-31

    There is a need for high-dose secondary calibration laboratories to serve the multi-billion dollar radiation processing industry. This need is driven by the desires of industry for less costly calibrations and faster calibration-cycle response time. Services needed include calibration irradiations of routine processing dosimeters and the supply of reference standard transfer dosimeters for irradiation in the production processing facility. In order to provide measurement quality assurance and to demonstrate consistency with national standards, the high-dose secondary laboratories would be accredited by means of an expansion of an existing National Voluntary Laboratory Accreditation Program. A laboratory performance criteria document is under development to implement the new program.

  12. Conformal house

    DEFF Research Database (Denmark)

    Ryttov, Thomas Aaby; Sannino, Francesco

    2010-01-01

    fixed point. As a consistency check we recover the previously investigated bounds of the conformal windows when restricting to a single matter representation. The earlier conformal windows can be imagined to be part now of the new conformal house. We predict the nonperturbative anomalous dimensions...... at the infrared fixed points. We further investigate the effects of adding mass terms to the condensates on the conformal house chiral dynamics and construct the simplest instanton induced effective Lagrangian terms...

  13. Risk of atrial fibrillation with high-dose corticosteroids.

    Science.gov (United States)

    Chiappini, Bruno; El Khoury, Gebrine

    2006-11-01

    Atrial fibrillation (AF) is the most common sustained arrhythmia observed in clinical practice. Some drugs have been associated with the onset of AF, but knowledge about the role of drugs in the development of AF is scarce. High-dose corticosteroid therapy has been associated with the development of AF, but this is mainly based on case reports. Therefore, the authors review the available data in the international literature about the cause-effect relationship between corticosteroid therapy and the onset of AF.

  14. Precision, high dose radiotherapy: helium ion treatment of uveal melanoma

    Energy Technology Data Exchange (ETDEWEB)

    Saunders, W.M.; Char, D.H.; Quivey, J.M.; Castro, J.R.; Chen, G.T.Y.; Collier, J.M.; Cartigny, A.; Blakely, E.A.; Lyman, J.T.; Zink, S.R.

    1985-02-01

    The authors report on 75 patients with uveal melanoma who were treated by placing the Bragg peak of a helium ion beam over the tumor volume. The technique localizes the high dose region very tightly around the tumor volume. This allows critical structures, such as the optic disc and the macula, to be excluded from the high dose region as long as they are 3 to 4 mm away from the edge of the tumor. Careful attention to tumor localization, treatment planning, patient immobilization and treatment verification is required. With a mean follow-up of 22 months (3 to 60 months) the authors have had only five patients with a local recurrence, all of whom were salvaged with another treatment. Pretreatment visual acuity has generally been preserved as long as the tumor edge is at least 4 mm away from the macula and optic disc. The only serious complication to date has been an 18% incidence of neovascular glaucoma in the patients treated at our highest dose level. Clinical results and details of the technique are presented to illustrate potential clinical precision in administering high dose radiotherapy with charged particles such as helium ions or protons.

  15. Characterization of TLD-100 in powders for dosimetric quality control of {sup 192} Ir sources used in brachytherapy of high dose rate; Caracterizacion de TLD-100 en polvo para control de calidad dosimetrico de fuentes de Ir{sup 192} usadas en braquiterapia de alta tasa de dosis

    Energy Technology Data Exchange (ETDEWEB)

    Loaiza C, S.P

    2007-07-01

    The Secondary Standard Dosimetric at the National Institute of Nuclear Research (ININ) calibrated a lot of powdered TLD-100 (LiF:Mg,Ti) in terms of absorbed dose to water D{sub w} for the energy of: {sup 60}Co, {sup 137C}s, X rays of 250 and 50 kVp. Later on, it is carried out an interpolation of the calibration for the energy of the {sup 192}Ir. This calibration is part of a dosimetric quality control program, to solve the problems of traceability for the measurements carried out by the users of {sup 192}Ir sources employed in the treatments of High Dose Rate Brachytherapy (HDR) at the Mexican Republic. The calibrations of the radiation beams are made with the following protocols: IAEA TRS-398 for the {sup 60}Co for D{sub w}, using a secondary standard ionization chamber PTW N30013 calibrated in D{sub w} by the National Research Council (NRC, Canada). AAPM TG-43 for D{sub w} in terms of the strength kerma Sk, calibrating this last one quantity for the {sup 137}Cs radioactive source, with a well chamber HDR 1000 PLUS traceable to the University of Wisconsin (US). AAPM TG-61 for X ray of 250 and 50 kVp for D{sub w} start to Ka using field standard a Farmer chamber PTW 30001 traceable to K for the Central Laboratory of Electric Industries (CLEI, France). The calibration curves (CC) they built for the response of the powder TLD: R{sub TLD} vs D{sub w}: For the energy of {sup 60}Co, {sup 137}Cs, X rays of 250 and 50 kVp. Fitting them with the least square method weighed by means of a polynomial of second grade that corrects the supra linearity of the response. iii. Each one of the curves was validated with a test by lack of fitting and for the Anderson Darling normality test, using the software MINITAB in both cases. iv. The sensibility factor (F{sub s}) for each energy corresponds to the slope of the CC, v. The F{sub s} for the two {sup 192}Ir sources used are interpolated: one for a Micro Selectron source and the other one a Vari Source source. Finally, a couple of

  16. Breast conserving treatment of breast carcinoma T2 ({<=} 4 cm) and T3 by neoadjuvant chemotherapy, quadrantectomy, high dose rate brachytherapy as a boost, external beam radiotherapy and adjuvant chemotherapy: local control and overall survival analysis; Tratamento conservador do cancer de mama T2 ({<=} 4 cm) e T3 por quimioterapia neoadjuvante, quadrantectomia, braquiterapia com alta taxa de dose como reforco de dose, teleterapia complementar e quimioterapia adjuvante: analise de controle local e sobrevida global

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Celia Regina; Miziara Filho, Miguel Abrao; Fogaroli, Ricardo Cesar; Baraldi, Helena Espindola; Pellizzon, Antonio Cassio Assis; Pelosi, Edilson Lopes [Instituto do Cancer Dr. Arnaldo Vieira de Carvalho (ICAVC), Sao Paulo, SP (Brazil). Servico de Radioterapia], e-mail: celiarsoares@terra.com.br; Fristachi, Carlos Elias [Instituto do Cancer Dr. Arnaldo Vieira de Carvalho (ICAVC), Sao Paulo, SP (Brazil). Servico de Onco-Ginecologia e Mastologia; Paes, Roberto Pinto [Instituto do Cancer Dr. Arnaldo Vieira de Carvalho (ICAVC), Sao Paulo, SP (Brazil)

    2008-12-15

    Objective: to assess the treatment of breast cancer T2 ({<=} 4 cm) and T3 through neoadjuvant chemotherapy, quadrantectomy and high dose rate brachytherapy as a boost, complementary radiotherapy and adjuvant chemotherapy, considering local control and overall survival. Material and method: this clinical prospective descriptive study was based on the evaluation of 88 patients ranging from 30 to 70 years old, with infiltrating ductal carcinoma, clinical stage IIb and IIIa, responsive to the neoadjuvant chemotherapy, treated from June/1995 to December/2006. Median follow-up was 58 months. Using clinical methods the tumor was evaluated before and after three or four cycles of chemotherapy based on anthracyclines. Overall survival and local control were assessed according to Kaplan-Meier methodology. Results: Local control and overall survival in five years were 90% and 73.5%, respectively. Conclusion: local control and overall survival were comparable to other forms of treatment. (author)

  17. Preventing and Managing Toxicities of High-Dose Methotrexate.

    Science.gov (United States)

    Howard, Scott C; McCormick, John; Pui, Ching-Hon; Buddington, Randall K; Harvey, R Donald

    2016-12-01

    : High-dose methotrexate (HDMTX), defined as a dose higher than 500 mg/m(2), is used to treat a range of adult and childhood cancers. Although HDMTX is safely administered to most patients, it can cause significant toxicity, including acute kidney injury (AKI) in 2%-12% of patients. Nephrotoxicity results from crystallization of methotrexate in the renal tubular lumen, leading to tubular toxicity. AKI and other toxicities of high-dose methotrexate can lead to significant morbidity, treatment delays, and diminished renal function. Risk factors for methotrexate-associated toxicity include a history of renal dysfunction, volume depletion, acidic urine, and drug interactions. Renal toxicity leads to impaired methotrexate clearance and prolonged exposure to toxic concentrations, which further worsen renal function and exacerbate nonrenal adverse events, including myelosuppression, mucositis, dermatologic toxicity, and hepatotoxicity. Serum creatinine, urine output, and serum methotrexate concentration are monitored to assess renal clearance, with concurrent hydration, urinary alkalinization, and leucovorin rescue to prevent and mitigate AKI and subsequent toxicity. When delayed methotrexate excretion or AKI occurs despite preventive strategies, increased hydration, high-dose leucovorin, and glucarpidase are usually sufficient to allow renal recovery without the need for dialysis. Prompt recognition and effective treatment of AKI and associated toxicities mitigate further toxicity, facilitate renal recovery, and permit patients to receive other chemotherapy or resume HDMTX therapy when additional courses are indicated. High-dose methotrexate (HDMTX), defined as a dose higher than 500 mg/m(2), is used for a range of cancers. Although HDMTX is safely administered to most patients, it can cause significant toxicity, including acute kidney injury (AKI), attributable to crystallization of methotrexate in the renal tubular lumen, leading to tubular toxicity. When AKI occurs

  18. Successful management of a patient with toxic epidermal necrolysis by high dose intravenous immunoglobulin

    Directory of Open Access Journals (Sweden)

    Ali Güneş

    2013-12-01

    Full Text Available Toxic epidermal necrolysis (TEN is a disease that mostly caused by drug use and characterized by acute onset and rapidly progressive necrosis of the epidermis. In severe cases, mortality rate change between 20% and 60%. Although there is no definite treatment, some authors have reported the effectiveness of intravenous immunoglobulin (IVIG. Here, we presented a 9-year-old male patient with TEN. Skin rashes of patient began after three days of using ibuprofen, metronidazole, clarithromycin, and procaine penicillin. Skin lesions resembling second-degree burns covered 50% of the patient’s body surface area. After giving high-dose IVIG, the patient’s lesions improved. This case is an example of effect of high dose IVIG in the treatment of TEN. J Clin Exp Invest 2013; 4 (4: 503-505

  19. Enhanced lipid accumulation of photoautotrophic microalgae by high-dose CO2 mimics a heterotrophic characterization.

    Science.gov (United States)

    Sun, Zhilan; Dou, Xiao; Wu, Jun; He, Bing; Wang, Yuancong; Chen, Yi-Feng

    2016-01-01

    Microalgae possess higher photosynthetic efficiency and accumulate more neutral lipids when supplied with high-dose CO2. However, the nature of lipid accumulation under conditions of elevated CO2 has not been fully elucidated so far. We now revealed that the enhanced lipid accumulation of Chlorella in high-dose CO2 was as efficient as under heterotrophic conditions and this may be attributed to the driving of enlarged carbon source. Both photoautotrophic and heterotrophic cultures were established by using Chlorella sorokiniana CS-1. A series of changes in the carbon fixation, lipid accumulation, energy conversion, and carbon-lipid conversion under high-dose CO2 (1-10%) treatment were characterized subsequently. The daily carbon fixation rate of C. sorokiniana LS-2 in 10% CO2 aeration was significantly increased compared with air CO2. Correspondingly, double oil content (28%) was observed in 10% CO2 aeration, close to 32.3% produced under heterotrophic conditions. In addition, with 10% CO2 aeration, the overall energy yield (Ψ) in Chlorella reached 12.4 from 7.3% (with air aeration) because of the enhanced daily carbon fixation rates. This treatment also improved the energetic lipid yield (Ylipid/Es) with 4.7-fold, tending to the heterotrophic parameters. More significantly, 2.2 times of carbon-lipid conversion efficiency (ηClipid/Ctotal, 42.4%) was observed in 10% CO2 aeration, towards to 53.7% in heterotrophic cultures, suggesting that more fixed carbon might flow into lipid synthesis under both 10% CO2 aeration and heterotrophic conditions. Taken together, all our evidence showed that 10% CO2 may push photoautotrophic Chlorella to display heterotrophic-like efficiency at least in lipid production. It might bring us an efficient model of lipid production based on microalgal cells with high-dose CO2, which is essential to sustain biodiesel production at large scales.

  20. Radioterapia adjuvante no tratamento do câncer de endométrio: experiência com a associação de radio-terapia externa e braquiterapia de alta taxa de dose Adjuvant radiation therapy for the treatment of endometrial cancer: experience with combination of external radiation therapy and high-dose rate brachytherapy

    Directory of Open Access Journals (Sweden)

    Michael Jenwei Chen

    2005-12-01

    Full Text Available OBJETIVO: Analisar, retrospectivamente, os resultados da radioterapia externa (RT combinada a braquiterapia de alta taxa de dose (BATD, adjuvantes à cirurgia para o carcinoma de endométrio. MATERIAIS E MÉTODOS: Avaliamos 141 pacientes tratados com RT e BATD adjuvantes à cirurgia, no período de janeiro de 1993 a janeiro de 2001. RT pélvica foi realizada com dose mediana de 45 Gy, e BATD realizada na dose mediana de 24 Gy, em quatro inserções semanais de 6 Gy. A idade mediana das pacientes foi de 63 anos e a distribuição por estádio clínico (EC foi: EC I (FIGO, 52,4%; EC II, 13,5%; EC III, 29,8%; EC IV, 4,3%. RESULTADOS: Com seguimento mediano de 53,7 meses, a sobrevida livre de doença (SLD em cinco anos foi: EC I, 88,0%; EC II, 70,8%; EC III, 55,1%; EC IV, 50,0% (p = 0,0003. A sobrevida global em cinco anos foi: EC I, 79,6%; EC II, 74,0%; EC III, 53,6%; EC IV, 100,0% (p = 0,0062. Fatores que influíram na SLD foram grau histológico e histologia seropapilífera. Dos 33 casos que apresentaram recidiva da doença, em 13 (9,2% esta ocorreu na pelve, vagina ou cúpula vaginal. RT + BATD do fundo vaginal permitiram o controle da doença em 90,8% dos casos. CONCLUSÃO: A RT exerce papel fundamental no controle loco-regional do câncer de endométrio e permite excelentes taxas de cura nos estádios iniciais. Para os estádios mais avançados, a falha terapêutica tende a ser a distância, sugerindo a necessidade de complementação terapêutica sistêmica, com introdução de novas modalidades de tratamento, em particular a quimioterapia.OBJECTIVE: To review the results of adjuvant external beam radiation therapy (EBRT combined with high-dose rate brachytherapy (HDR-BT for the treatment of endometrial carcinoma. MATERIALS AND METHODS: We retrospectively evaluated 141 patients treated with EBRT and HDR-BT after surgery between January 1993 and January 2001. EBRT was performed with a median dose of 45 Gy, and HDR-BT was performed with a

  1. High-dose irradiated food: Current progress, applications, and prospects

    Science.gov (United States)

    Feliciano, Chitho P.

    2018-03-01

    Food irradiation as an established and mature technology has gained more attention in the food industry for ensuring food safety and quality. Primarily used for phytosanitary applications, its use has been expanded for developing various food products for varied purposes (e.g. ready-to-eat & ready-to-cook foods, hospital diets, etc.). This paper summarized and analyzed the recent progress and application of high-dose irradiation and discussed its prospects in the field of food product development, its safety and quality.

  2. Provider knowledge of trivalent inactivated and high-dose influenza vaccines.

    Science.gov (United States)

    Tewell, Chad; Wright, Patty W; Talbot, H Keipp

    2014-10-21

    The objective of this study was to assess provider knowledge about trivalent inactivated and high dose influenza vaccines. Hence, a 20-item survey was distributed to providers within the Internal Medicine department at an urban academic medical center. Two hundred and eighty-one (24.5%) providers responded. The correct response rate was 63.2%. The highest performing subspecialties were infectious diseases (80.5%), endocrinology (69.2%), and pulmonary (68%). Those who received an influenza vaccine during the most recent season scored significantly higher than those who did not (63.6% vs. 43.6%, p=.001). Areas where respondents did poorly included questions pertaining to contraindications to immunizations (27.4%), common adverse events after immunization (29.2%), target antigen (73.5%), number of strains in the trivalent inactivated vaccine (62.9%), and time to immunity (61.4%). High dose vaccine knowledge was poor, with 37% of providers unaware of its existence. Significant gaps in provider knowledge exist regarding both trivalent inactivated and high dose influenza vaccines. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Polybutadiene and Styrene-Butadiene rubbers for high-dose dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Lucas N. [Instituto Federal de Educacao, Ciencia e Tecnologia de Goias-IFG,Campus Goiania, Goiania -GO (Brazil); Instituto de Pesquisas Energeticas e Nucleares -IPEN, Sao Paulo-SP (Brazil); Vieira, Silvio L. [Instituto de Fisica, Universidade Federal de Goias-UFG, Campus Samambaia, Goiania-GO (Brazil); Schimidt, Fernando [Instituto Federal de Educacao, Ciencia e Tecnologia de Goias-IFG,Campus Inhumas, Inhumas-GO (Brazil); Antonio, Patricia L.; Caldas, Linda V.E. [Instituto de Pesquisas Energeticas e Nucleares -IPEN, Sao Paulo-SP (Brazil)

    2015-07-01

    Polybutadiene and Styrene-Butadiene are synthetical rubbers used widely for pneumatic tires manufacturing. In this research, the dosimeter characteristics of those rubbers were studied for application in high-dose dosimetry. The rubber samples were irradiated with doses of 10 Gy up to 10 kGy, using a {sup 60}Co Gamma Cell-220 system (dose rate of 1.089 kGy/h) and their readings were taken on a Fourier Transform Infrared Spectroscopy-FTIR system (model Frontier/Perkin Elmer). The ratios of two absorbance peaks were taken for each kind of rubber spectrum, Polybutadiene (1306/1130 cm{sup -1}) and Styrene-Butadiene (1449/1306 cm{sup -1}). The ratio calculated was used as the response to the irradiation, and is not uniform across the sample. From the results, it can be concluded for both rubbers: a) the dose-response curves may be useful for high-dose dosimetry (greater than 250 Gy); b) their response for reproducibility presented standard deviations lower than 2.5%; c) the relative sensitivity was higher for Styrene-Butadiene (1.86 kGy{sup -1}) than for Polybutadiene (1.81 kGy{sup -1}), d) for doses of 10 kGy to 200 kGy, there was no variation in the dosimetric response. Both types of rubber samples showed usefulness as high-dose dosimeters. (authors)

  4. Transportation Conformity

    Science.gov (United States)

    This section provides information on: current laws, regulations and guidance, policy and technical guidance, project-level conformity, general information, contacts and training, adequacy review of SIP submissions

  5. The influence of high doses of radiation in citrine stones

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, M. I. [Universidade Nove de Julho - UNINOVE, Rua Vergueiro 235/249, 01504-001 Sao Paulo (Brazil); Caldas, L. V. E., E-mail: miteixeira@ipen.br [Instituto de Pesquisas Energeticas e Nucleares / CNEN, Av. Lineu Prestes 2242, Cidade Universitaria, 05508-000 Sao Paulo (Brazil)

    2014-08-15

    The possibility of using samples of Brazilian stones as quartz, amethyst, topaz, jasper, etc. for high-dose dosimetry has been studied in recent years at IPEN, using the techniques of optical absorption (Oa), thermoluminescent (Tl), optically stimulated luminescence (OSL) and resonance paramagnetic electron (EPR). In this work, the Tl properties of citrine samples were studied. They were exposed to different doses of gamma radiation ({sup 60}Co). The natural citrine stone was extracted from a mine in Minas Gerais state, Brazil; it is a tecto silicate ranked as one of three-dimensional structure, showing clear yellow to golden brown color. The natural citrine stone is classified as quartz (SiO{sub 2}), and it has a lower symmetry and more compact reticulum. The Tl emission curve showed two peaks at 160 grades C and 220 grades C. To remove the Tl peak (160 grades C) of the sintered citrine pellet glow curves, different thermal treatments were tested during several time intervals. The Tl dose-response curve between 50 Gy and 100 kGy, the reproducibility of Tl response and the lower detection dose were obtained. The results show that citrine may be useful as high-dose detectors. (Author)

  6. Multifocal Electroretinography after High Dose Chloroquine Therapy for Malaria

    Directory of Open Access Journals (Sweden)

    Aline Correa de Carvalho

    2013-01-01

    Full Text Available Purpose: To investigate changes in multifocal electroretinography (mfERG parameters associated with high dose chloroquine therapy for treatment of malaria in the Amazonia region of Brazil. Methods: Forty-eight subjects who had received chloroquine treatment for single or multiple malaria infections with a cumulative dose ranging from 1,050 to 27,000mg were included. The control group consisted of 37 healthy aged-matched subjects. Data was collected on amplitude and implicit time of the N1, P1 and N2 waves in the central macular hexagon (R1 and in five concentric rings at different retinal eccentricities (R2-R6. Results: No significant difference was observed in any mfERG parameter between chloroquine treated patients and control subjects. A comparison with previous data obtained from patients with rheumatologic disorders in the same region of Brazil who had received larger cumulative doses of chloroquine and had displayed mfERG changes, indicated that retinal toxicity seems to be dependent on cumulative dose. Conclusion: Lack of mfERG changes in the current study suggests that intensive high dose chloroquine therapy for treatment of malaria is not associated with retinal toxicity.

  7. Workers’ Conformism

    Directory of Open Access Journals (Sweden)

    Nikolay Ivantchev

    2013-10-01

    Full Text Available Conformism was studied among 46 workers with different kinds of occupations by means of two modified scales measuring conformity by Santor, Messervey, and Kusumakar (2000 – scale for perceived peer pressure and scale for conformism in antisocial situations. The hypothesis of the study that workers’ conformism is expressed in a medium degree was confirmed partly. More than a half of the workers conform in a medium degree for taking risk, and for the use of alcohol and drugs, and for sexual relationships. More than a half of the respondents conform in a small degree for anti-social activities (like a theft. The workers were more inclined to conform for risk taking (10.9%, then – for the use of alcohol, drugs and for sexual relationships (8.7%, and in the lowest degree – for anti-social activities (6.5%. The workers who were inclined for the use of alcohol and drugs tended also to conform for anti-social activities.

  8. High-dose versus low-dose oxytocin for augmentation of delayed labour.

    Science.gov (United States)

    Kenyon, Sara; Tokumasu, Hironobu; Dowswell, Therese; Pledge, Debbie; Mori, Rintaro

    2013-07-13

    A major cause of failure to achieve spontaneous vaginal birth is delay in labour due to presumed inefficient uterine action. Oxytocin is given to increase contractions and high-dose regimens may potentially increase the number of spontaneous vaginal births, but as oxytocin can cause hyperstimulation of the uterus, there is a possibility of increased adverse events. To compare starting dose and increment dose of oxytocin for augmentation for women delayed in labour to determine whether augmentation by high-dose regimens of oxytocin improves labour outcomes and to examine the effect on both maternal/neonatal outcomes and women's birth experiences. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 May 2013) and reference lists of retrieved studies. We included all randomised and quasi-randomised controlled trials for women in delayed labour requiring augmentation by oxytocin comparing high-dose regimens (defined as starting dose and increment of equal to or more than 4 mU per minute) with low-dose regimens (defined as starting dose and an increment of less than 4 mU per minute). Increase interval: between 15 and 40 minutes. The separation of low- and high-dose regimens is based on an arbitrary decision. Four review authors undertook assessment of trial eligibility, risk of bias, and data extraction independently. We included four studies involving 644 pregnant women. Three studies were randomised controlled trials and one trial was a quasi-randomised study. A higher dose of oxytocin was associated with a significant reduction in length of labour reported from one trial (mean difference (MD) -3.50 hours; 95% confidence interval (CI) -6.38 to -0.62; one trial, 40 women). There was a decrease in the rate of caesarean section (risk ratio (RR) 0.62; 95% CI 0.44 to 0.86 four trials, 644 women) and an increase in the rate of spontaneous vaginal birth in the high-dose group (RR 1.35; 95% CI 1.13 to 1.62, three trials, 444 women), although for both

  9. The Conformity Rate of the Principles of Catheterization Nursing Care in Women with the Standards in Selected Hospital of Qom University of Medical Sciences, 2015, Iran

    Directory of Open Access Journals (Sweden)

    Fahime Rostami Nouri

    2016-07-01

    Full Text Available Background and Objectives: Given the increasing prevalence of use of urinary catheter, nurses as one of the largest and the most important health care provider groups, should have extensive knowledge and skills in order to provide standard health care. This study was conducted to determine the conformity rate of the principles of catheterization nursing care in women with the standards in selected Hospital of Qom University of Medical Sciences, 2015. Methods: In this descriptive cross-sectional study, 195 cases of catheterization nursing care in women, were investigated using event sampling in one of the hospitals affiliated to Qom University of Medical Sciences, in 2015. Data were gathered through Nurses' Demographic Information Questionnaire and checklist of catheterization nursing care in women. Results: In this study, the conformity rate of catheterization nursing care with the standards was 70.8% (moderate; 29.2% of the care was desirable; and 0% was poor. Conclusion: According to the results, nurses’ performance in the catheterization nursing care in women was in moderate level compared to the standards. In order to improve the quality of cares, implementation of nursing clinical guidelines for women catheterization, and clinical supervision by nurse managers, are suggested.  

  10. Cone damage in patients receiving high-dose irofulven treatment.

    Science.gov (United States)

    Lee, Michael S; Gupta, Nisha; Penson, Richard T; Loewenstein, John; Wepner, Meredith S; Seiden, Michael V; Milam, Ann H

    2005-01-01

    To describe the clinical, perimetric, and electroretinographic (ERG) results of 4 patients with cone dysfunction following irofulven treatment including the histopathologic and immunocytochemical features of one patient's retinas. Observational case series. The patients were examined clinically, including perimetric and ERG evaluations. Eyes from patient 1 and healthy postmortem eyes were processed for histopathologic and immunocytochemistry studies with antibodies specific for cones, rods, and reactive Müller cells. Clinical signs and symptoms, perimetry, ERG, retinal histopathologic and immunocytochemistry study results. All 4 patients had ERG changes consistent with abnormal cone responses and relatively normal rod responses. Compared with control eyes, the retina of patient 1 had approximately half the normal numbers of macular cones and fewer peripheral cones. The number of rods were normal but all rod and cone outer segments were shortened. High-dose irofulven treatment causes cone-specific damage with relative sparing of rods.

  11. Single-Agent High-Dose Cyclophosphamide for Graft-versus-Host Disease Prophylaxis in Human Leukocyte Antigen-Matched Reduced-Intensity Peripheral Blood Stem Cell Transplantation Results in an Unacceptably High Rate of Severe Acute Graft-versus-Host Disease.

    Science.gov (United States)

    Bradstock, Kenneth F; Bilmon, Ian; Kwan, John; Micklethwaite, Kenneth; Blyth, Emily; Deren, Stephanie; Bayley, Angela; Gebski, Val; Gottlieb, David

    2015-05-01

    High-dose cyclophosphamide given early after allogeneic hemopoietic cell transplantation has been shown to be effective prophylaxis against graft-versus-host disease (GVHD) in the setting of HLA-matched myeloablative bone marrow grafts, allowing avoidance of long-term immunosuppression with calcineurin inhibitors in some patients. Whether this approach is feasible using granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood stem cell grafts is unknown. We conducted an exploratory phase 2 trial of cyclophosphamide given at 50 mg/kg i.v. on days 3 and 4 after transplantation as sole GVHD prophylaxis in recipients of G-CSF-mobilized peripheral blood stem cell grafts from HLA-matched related or unrelated donors after reduced-intensity conditioning therapy with fludarabine, carmustine, and melphalan. Five patients, ages 52 to 67 years, with high-risk hematologic malignancies were enrolled. Four of the 5 developed severe acute GVHD of grades 3 to 4, requiring treatment with methylprednisolone and cyclosporine; 3 were steroid refractory and were given salvage therapy. One of these 4 patients died of hepatic GVHD, one died of sepsis, and 2 survived. We conclude that post-transplantation cyclophosphamide is inadequate as sole GVHD prophylaxis in the context of peripheral blood reduced-intensity conditioning transplantations from HLA-matched donors. This trial is registered at ACTRN12613001154796. Copyright © 2015 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  12. Efficiency of Stereotactic Conformal Radiotherapy in Lung Metastases with Active Breathing Control

    Directory of Open Access Journals (Sweden)

    Olga Yu. Anikeeva, PhD

    2013-06-01

    Full Text Available Twenty four patients with lung metastases underwent radiosurgery treatment between October 2010 and December 2012. Stereotactic conformal high-dose radiation therapy with Active Breathing Control (ABC was conducted using the volumetric modulated arc therapy (VMAT technique. The median overall follow-up was 18 months (range 6-24 months, overall survival was 75%, and local control rate was 92%. The median time to progression was 4 months (range 1-18 months.There have been no cases of leucopenia, radiation esophagitis, mediastinitis or severe acute radiation pneumonitis. The late radiation effects Grade 2, according to the LENT SOMA scales, was observed in one patient (4%. The results of this study indicate that the usage of the stereotactic high-dose radiation therapy with ABC is safe and effective in the treatment of lung metastases.

  13. Prognosis of emergency room stabilization of decompensated congestive heart failure with high dose lasix

    Directory of Open Access Journals (Sweden)

    Mahboob Pouraghaei

    2015-06-01

    Full Text Available Objective: Congestive heart failure (CHF has become one of the most important health care problems in western countries. This article focuses on the outpatient diagnosis and management of heart failure. We want to compare the outcome of patients who were treated with high dose diuretics in the emergency department (ED without admission with patients who were admitted to hospital for standard treatment. Methods: This was a randomized prospective clinical trial study. The patients who came to the ED from March 20, 2008 up to August 20, 2008 were divided into two groups randomly. The length of ED stay in the experimental group was documented. Also, readmission and mortality in 6 months and satisfaction in both groups were taken into consideration. All data were analyzed using SPSS 15.0. Results: In experimental group, the rate of recurrent admission, expiration, discharge, clinic visit, and clinic admission was 8%, 4%, 29%, 18%, and 0% respectively. On the other hand, in control group it was 16%, 40%, 18%, 22%, and 2% respectively. Additionally, there was a significant difference between these groups (P = 0.00. Conclusion: This study is the first regional prospective trial to comprehensively examine the therapeutic management in patients with CHF. This study, comparing the high dose diuretic efficacy in the decreasing of hospital stay and readmission; and decreasing mortality rate with routine therapy, showed that there was a significant difference between these two strategies in the mortality rate, readmission, and length of hospital stay (P = 0.00.

  14. General Conformity

    Science.gov (United States)

    The General Conformity requirements ensure that the actions taken by federal agencies in nonattainment and maintenance areas do not interfere with a state’s plans to meet national standards for air quality.

  15. Conformal Infinity

    Directory of Open Access Journals (Sweden)

    Frauendiener Jörg

    2000-08-01

    Full Text Available The notion of conformal infinity has a long history within the research in Einstein's theory of gravity. Today, ``conformal infinity'' is related with almost all other branches of research in general relativity, from quantisation procedures to abstract mathematical issues to numerical applications. This review article attempts to show how this concept gradually and inevitably evolved out of physical issues, namely the need to understand gravitational radiation and isolated systems within the theory of gravitation and how it lends itself very naturally to solve radiation problems in numerical relativity. The fundamental concept of null-infinity is introduced. Friedrich's regular conformal field equations are presented and various initial value problems for them are discussed. Finally, it is shown that the conformal field equations provide a very powerful method within numerical relativity to study global problems such as gravitational wave propagation and detection.

  16. Conformal Infinity

    Directory of Open Access Journals (Sweden)

    Frauendiener Jörg

    2004-01-01

    Full Text Available The notion of conformal infinity has a long history within the research in Einstein's theory of gravity. Today, 'conformal infinity' is related to almost all other branches of research in general relativity, from quantisation procedures to abstract mathematical issues to numerical applications. This review article attempts to show how this concept gradually and inevitably evolved from physical issues, namely the need to understand gravitational radiation and isolated systems within the theory of gravitation, and how it lends itself very naturally to the solution of radiation problems in numerical relativity. The fundamental concept of null-infinity is introduced. Friedrich's regular conformal field equations are presented and various initial value problems for them are discussed. Finally, it is shown that the conformal field equations provide a very powerful method within numerical relativity to study global problems such as gravitational wave propagation and detection.

  17. Impact of high dose vitamin C on platelet function.

    Science.gov (United States)

    Mohammed, Bassem M; Sanford, Kimberly W; Fisher, Bernard J; Martin, Erika J; Contaifer, Daniel; Warncke, Urszula Osinska; Wijesinghe, Dayanjan S; Chalfant, Charles E; Brophy, Donald F; Fowler Iii, Alpha A; Natarajan, Ramesh

    2017-02-04

    To examine the effect of high doses of vitamin C (VitC) on ex vivo human platelets (PLTs). Platelet concentrates collected for therapeutic or prophylactic transfusions were exposed to: (1) normal saline (control); (2) 0.3 mmol/L VitC (Lo VitC); or (3) 3 mmol/L VitC (Hi VitC, final concentrations) and stored appropriately. The VitC additive was preservative-free buffered ascorbic acid in water, pH 5.5 to 7.0, adjusted with sodium bicarbonate and sodium hydroxide. The doses of VitC used here correspond to plasma VitC levels reported in recently completed clinical trials. Prior to supplementation, a baseline sample was collected for analysis. PLTs were sampled again on days 2, 5 and 8 and assayed for changes in PLT function by: Thromboelastography (TEG), for changes in viscoelastic properties; aggregometry, for PLT aggregation and adenosine triphosphate (ATP) secretion in response to collagen or adenosine diphosphate (ADP); and flow cytometry, for changes in expression of CD-31, CD41a, CD62p and CD63. In addition, PLT intracellular VitC content was measured using a fluorimetric assay for ascorbic acid and PLT poor plasma was used for plasma coagulation tests [prothrombin time (PT), partial thrombplastin time (PTT), functional fibrinogen] and Lipidomics analysis (UPLC ESI-MS/MS). VitC supplementation significantly increased PLTs intracellular ascorbic acid levels from 1.2 mmol/L at baseline to 3.2 mmol/L (Lo VitC) and 15.7 mmol/L (Hi VitC, P 0.05). PLT function assayed by TEG, aggregometry and flow cytometry was not significantly altered by Lo or Hi VitC for up to 5 d. However, PLTs exposed to 3 mmol/L VitC for 8 d demonstrated significantly increased R and K times by TEG and a decrease in the α-angle (P 0.05). Collagen and ADP-induced ATP secretion was also not different between the three groups (P > 0.05). Finally, VitC at the higher dose (3 mmol/L) also induced the release of several eicosanoids including thromboxane B2 and prostaglandin E2, as well as products of

  18. Comparison of survival rates between 3D conformal radiotherapy and intensity-modulated radiotherapy in patients with stage Ⅲ non–small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Kong M

    2016-11-01

    Full Text Available Moonkyoo Kong, Seong Eon Hong Department of Radiation Oncology, Kyung Hee University Medical Center, Kyung Hee University School of Medicine, Seoul, Republic of Korea Purpose: Randomized trials showing a clear survival benefit of intensity-modulated radiotherapy (IMRT over 3-dimensional conformal radiotherapy (3D-CRT in the treatment of lung cancer are lacking. This study compared the survival rates of patients with stage III non-small cell lung cancer who were treated with either 3D-CRT or IMRT and analyzed the prognostic factors for survival.Methods: From January 2008 to July 2015, 19 patients were treated with IMRT and 30 were treated with 3D-CRT in our institution. The choice between 3D-CRT and IMRT was determined by the physician based on tumor extent and general condition of the patients. The primary endpoint of this study was overall survival. The secondary endpoints were loco-regional recurrence-free survival, distant metastasis-free survival, and the incidence of radiation-induced lung and esophageal toxicities. Results: The 1- and 2-year overall survival rates were 94.7% and 77.1% in the IMRT group and 76.7% and 52.5% in the 3D-CRT group, respectively. The overall survival rates of the IMRT group were higher than those of the 3D-CRT group; however, these differences were not statistically significant (P=0.072. Gross tumor volume was significantly associated with the overall survival rate. The 1- and 2-year loco-regional recurrence-free survival rates were 63.2% and 51% in the IMRT group and 67.5% and 48.1% in the 3D-CRT group (P=0.897, respectively. The 1- and 2-year distant metastasis-free survival rates were 78.9% and 68.4% in the IMRT group and 62.6% and 40.9% in the 3D-CRT group (P=0.120, respectively. Chemotherapy and treatment interruption were significantly associated with distant metastasis-free survival.Conclusion: IMRT showed comparable or better overall survival compared with 3D-CRT in patients with stage III non-small cell

  19. High doses of methylprednisolone in the management of caustic esophageal burns.

    Science.gov (United States)

    Usta, Merve; Erkan, Tülay; Cokugras, Fugen Cullu; Urganci, Nafiye; Onal, Zerrin; Gulcan, Mahir; Kutlu, Tufan

    2014-06-01

    Caustic substance ingestion in childhood is a public health issue in developing countries, and several management protocols have been proposed to prevent the resulting esophageal strictures. The role of corticosteroids in preventing corrosive-induced strictures is controversial. Our aim was to study the influence of high doses of corticosteroids in preventing esophageal strictures. Eighty-three children with a mean age of 4.10 6 2.63 years and with grade IIb esophageal burns (an esophagogastroscopy was performed within 24–48 hours of injury) due to corrosive substance ingestion were enrolled in our study between 2005 and 2008. Forty-two children (study group) received methylprednisolone (1 g/1.73 m2 per day for 3 days), ranitidine, ceftriaxone, and total parenteral nutrition. Forty-one children (control group) were administered the same regimen excluding methylprednisolone. Stricture development was compared between groups based on endoscopic and radiologic findings. During the endoscopic examination, stricture development was observed in 4 patients (10.8%) in the study group and in 12 patients (30%) in the control group. The difference was statistically significant (P = .038). The stricture development rate in the upper gastrointestinal system with barium meal was 14.3% and 45.0% in the study and control groups, respectively. The difference was statistically significant (P = .004). The duration of total parenteral nutrition was shorter in the study group compared with the control group (P = .001). High doses of methylprednisolone were well tolerated in the study group without any side effects. High doses of methylprednisolone used for the management of grade IIb esophageal burns may reduce stricture development.

  20. High doses of biotin in chronic progressive multiple sclerosis: a pilot study.

    Science.gov (United States)

    Sedel, Frédéric; Papeix, Caroline; Bellanger, Agnès; Touitou, Valérie; Lebrun-Frenay, Christine; Galanaud, Damien; Gout, Olivier; Lyon-Caen, Olivier; Tourbah, Ayman

    2015-03-01

    No drug has been found to have any impact on progressive multiple sclerosis (MS). Biotin is a vitamin acting as a coenzyme for carboxylases involved in key steps of energy metabolism and fatty acids synthesis. Among others, biotin activates acetylCoA carboxylase, a potentially rate-limiting enzyme in myelin synthesis. The aim of this pilot study is to assess the clinical efficacy and safety of high doses of biotin in patients suffering from progressive MS. Uncontrolled, non-blinded proof of concept study 23 consecutive patients with primary and secondary progressive MS originated from three different French MS reference centers were treated with high doses of biotin (100-300mg/day) from 2 to 36 months (mean=9.2 months). Judgement criteria varied according to clinical presentations and included quantitative and qualitative measures. In four patients with prominent visual impairment related to optic nerve injury, visual acuity improved significantly. Visual evoked potentials in two patients exhibited progressive reappearance of P100 waves, with normalization of latencies in one case. Proton magnetic resonance spectroscopy (H-MRS) in one case showed a progressive normalization of the Choline/Creatine ratio. One patient with left homonymous hemianopia kept on improving from 2 to 16 months following treatment׳s onset. Sixteen patients out of 18 (89%) with prominent spinal cord involvement were considered as improved as confirmed by blinded review of videotaped clinical examination in 9 cases. In all cases improvement was delayed from 2 to 8 months following treatment׳s onset. These preliminary data suggest that high doses of biotin might have an impact on disability and progression in progressive MS. Two double-blind placebo-controlled trials are on going. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  1. High-dose radiation sensor with wireless optical detection

    Science.gov (United States)

    Knapkiewicz, Paweł; Augustyniak, Izabela; Sareło, Katarzyna; Gorecka-Drzazga, Anna; Dziuban, Jan

    2017-05-01

    We present a miniature silicon-glass MEMS sensor for measurement of high doses of ionizing radiation (above 10 kGy) using a novel wireless optical detection method. The radiation sensor is a miniaturized version of the so-called hydrogen dosimeter. An amount of high-density polyethylene, located inside the MEMS sensor, degrades under ionizing radiation, releasing gaseous hydrogen. The increasing pressure deflects the thin silicon membrane. The sensor’s destructive and proportional modes of work are also proposed. In the destructive mode, sensors provide in situ information on excessive and discrete levels of radiation. The optical detection method is based on an optical head consisting of a moving membrane and a silicon screen with a matrix of micro-holes. Laser light is reflected from the membrane and scattered when the membrane is deflected, in the process illuminating the holes on the silicon screen. The number of illuminated holes is a function of the degree of membrane deflection; the transformation of the holes to the deflection allows for the calculation of pressure and eventually the dose of ionizing radiation.

  2. High-dose processing and application to Korean space foods

    Energy Technology Data Exchange (ETDEWEB)

    Song, Beom-Seok; Park, Jin-Gyu; Park, Jae-Nam; Han, In-Jun; Choi, Jong-il [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Kim, Jae-Hun [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Korea Astronaut Project Division, Korea Aerospace Research Institute, Daejeon 305-333 (Korea, Republic of); Byun, Myung-Woo [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Kang, Sang-Wook; Choi, Gi-Hyuk [Korea Astronaut Project Division, Korea Aerospace Research Institute, Daejeon 305-333 (Korea, Republic of); Lee, Ju-Woon [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of)], E-mail: sjwlee@kaeri.re.kr

    2009-07-15

    Nutrition bar, Ramen (ready-to-cook noodle), and two Korean traditional foods (Kimchi, fermented vegetable; Sujeonggwa, cinnamon beverage) have been developed as space foods using high-dose gamma irradiation. Addition of calcium lactate and vitamin C, a mild heating, deep-freezing, and gamma irradiation at 25 kGy were conducted to prepare Kimchi as a ready-to-eat space food. Sterilization of Space Kimchi (SK) was confirmed by a microbiological test. The hardness of the Space Kimchi was lower than the untreated Kimchi (CON), but higher than the irradiated only Kimchi. Sensory attributes of the SK were similar to CON, and maintained during preservation at 35 {sup o}C for 30 days. The optimal doses for eliminating the contaminated microbes and maintaining the qualities of the Nutrition bars, Ramen, and Sujeonggwa were determined at 15, 10 and 6 kGy, respectively. All the Korean space food were certificated for use in space flight conditions of 30 days by the Russian Institute for Biomedical Problems.

  3. High-dose processing and application to Korean space foods

    Science.gov (United States)

    Song, Beom-Seok; Park, Jin-Gyu; Park, Jae-Nam; Han, In-Jun; Choi, Jong-il; Kim, Jae-Hun; Byun, Myung-Woo; Kang, Sang-Wook; Choi, Gi-Hyuk; Lee, Ju-Woon

    2009-07-01

    Nutrition bar, Ramen (ready-to-cook noodle), and two Korean traditional foods ( Kimchi, fermented vegetable; Sujeonggwa, cinnamon beverage) have been developed as space foods using high-dose gamma irradiation. Addition of calcium lactate and vitamin C, a mild heating, deep-freezing, and gamma irradiation at 25 kGy were conducted to prepare Kimchi as a ready-to-eat space food. Sterilization of Space Kimchi (SK) was confirmed by a microbiological test. The hardness of the Space Kimchi was lower than the untreated Kimchi (CON), but higher than the irradiated only Kimchi. Sensory attributes of the SK were similar to CON, and maintained during preservation at 35 °C for 30 days. The optimal doses for eliminating the contaminated microbes and maintaining the qualities of the Nutrition bars, Ramen, and Sujeonggwa were determined at 15, 10 and 6 kGy, respectively. All the Korean space food were certificated for use in space flight conditions of 30 days by the Russian Institute for Biomedical Problems.

  4. High dose tetrabromobisphenol A impairs hippocampal neurogenesis and memory retention.

    Science.gov (United States)

    Kim, Ah Hyun; Chun, Hye Jeong; Lee, Seulah; Kim, Hyung Sik; Lee, Jaewon

    2017-08-01

    Tetrabromobisphenol A (TBBPA) is a brominated flame retardant that is commonly used in commercial and household products, such as, computers, televisions, mobile phones, and electronic boards. TBBPA can accumulate in human body fluids, and it has been reported that TBBPA possesses endocrine disruptive activity. However, the neurotoxic effect of TBBPA on hippocampal neurogenesis has not yet been investigated. Accordingly, the present study was undertaken to evaluate the effect of TBBPA on adult hippocampal neurogenesis and cognitive function. Male C57BL/6 mice were orally administrated vehicle or TBBPA (20 mg/kg, 100 mg/kg, or 500 mg/kg daily) for two weeks. TBBPA was observed to significantly and dose-dependently reduce the survival of newly generated cells in the hippocampus but not to affect the proliferation of newly generated cells. Numbers of hippocampal BrdU and NeuN positive cells were dose-dependently reduced by TBBPA, indicating impaired neurogenesis in the hippocampus. Interestingly, glial activation without neuronal death was observed in hippocampi exposed to TBBPA. Furthermore, memory retention was found to be adversely affected by TBBPA exposure by a mechanism involving suppression of the BDNF-CREB signaling pathway. The study suggests high dose TBBPA disrupts hippocampal neurogenesis and induces associated memory deficits. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Transient tetraparesis after intrathecal and high-dose systemic methotrexate.

    Science.gov (United States)

    Massenkeil, G; Späth-Schwalbe, E; Flath, B; Gottschalk, S; Lehmann, R; Arnold, R

    1998-11-01

    Aggressive polychemotherapy, intrathecal cytostatic prophylaxis and cranial irradiation have contributed to the remarkable improvement in the prognosis of acute lymphoblastic leukemia (ALL) and subtypes of high-grade non-Hodgkin's lymphoma (NHL) and the reduction of central nervous system (CNS) relapses. Early and late neurologic changes have been observed after different CNS-directed therapies. We report on the rare event of an acute tetraparesis after methotrexate (MTX) without other CNS-directed therapy. A young female with a diffuse large B-cell lymphoma developed signs of meningeal irritation a few hours after intrathecal prophylaxis with MTX, cytosine-arabinoside and dexamethasone. She recovered quickly. Ten days after her last course of systemic chemotherapy including high dose MTX she was admitted with a tetraparesis and motoric aphasia. A computer assisted tomography (CT) scan was normal. On magnetic resonance imaging (MRI) hyperintense white matter lesions were visible in the periventricular white matter. Initially, the radiologic signs were progressive while the patient's clinical condition improved. MRI controls after complete neurologic normalization revealed delayed partial regression of the white matter abnormalities. The patient has now been free of neurologic symptoms for 16 months. This case report demonstrates acute and subacute neurotoxic effects of MTX in the same patient and illustrates that radiologic CNS changes can persist irrespective of the disappearance of clinical symptoms.

  6. High doses of dextromethorphan, an NMDA antagonist, produce effects similar to classic hallucinogens.

    Science.gov (United States)

    Reissig, Chad J; Carter, Lawrence P; Johnson, Matthew W; Mintzer, Miriam Z; Klinedinst, Margaret A; Griffiths, Roland R

    2012-09-01

    Although reports of dextromethorphan (DXM) abuse have increased recently, few studies have examined the effects of high doses of DXM. This study in humans evaluated the effects of supratherapeutic doses of DXM and triazolam. Single, acute oral doses of DXM (100, 200, 300, 400, 500, 600, 700, and 800 mg/70 kg), triazolam (0.25 and 0.5 mg/70 kg), and placebo were administered to 12 healthy volunteers with histories of hallucinogen use, under double-blind conditions, using an ascending dose run-up design. Subjective, behavioral, and physiological effects were assessed repeatedly after drug administration for 6 h. Triazolam produced dose-related increases in subject-rated sedation, observer-rated sedation, and behavioral impairment. DXM produced a profile of dose-related physiological and subjective effects differing from triazolam. DXM effects included increases in blood pressure, heart rate, and emesis; increases in observer-rated effects typical of classic hallucinogens (e.g., distance from reality, visual effects with eyes open and closed, joy, anxiety); and participant ratings of stimulation (e.g., jittery, nervous), somatic effects (e.g., tingling, headache), perceptual changes, end-of-session drug liking, and mystical-type experience. After 400 mg/70 kg DXM, 11 of 12 participants indicated on a pharmacological class questionnaire that they thought they had received a classic hallucinogen (e.g., psilocybin). Drug effects resolved without significant adverse effects by the end of the session. In a 1-month follow-up, volunteers attributed increased spirituality and positive changes in attitudes, moods, and behavior to the session experiences. High doses of DXM produced effects distinct from triazolam and had characteristics that were similar to the classic hallucinogen psilocybin.

  7. High doses of dextromethorphan, an NMDA antagonist, produce effects similar to classic hallucinogens

    Science.gov (United States)

    Carter, Lawrence P.; Johnson, Matthew W.; Mintzer, Miriam Z.; Klinedinst, Margaret A.; Griffiths, Roland R.

    2013-01-01

    Rationale Although reports of dextromethorphan (DXM) abuse have increased recently, few studies have examined the effects of high doses of DXM. Objective This study in humans evaluated the effects of supratherapeutic doses of DXM and triazolam. Methods Single, acute, oral doses of DXM (100, 200, 300, 400, 500, 600, 700, 800 mg/70 kg), triazolam (0.25, 0.5 mg/70kg), and placebo were administered to twelve healthy volunteers w