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Sample records for high-dose single fraction

  1. Five-Year Outcomes of High-Dose Single-Fraction Spinal Stereotactic Radiosurgery

    International Nuclear Information System (INIS)

    Moussazadeh, Nelson; Lis, Eric; Katsoulakis, Evangelia; Kahn, Sweena; Svoboda, Marek; DiStefano, Natalie M.; McLaughlin, Lily; Bilsky, Mark H.; Yamada, Yoshiya; Laufer, Ilya

    2015-01-01

    Purpose: To characterize local tumor control and toxicity risk in very long-term survivors (>5 years) after high-dose spinal image guided, intensity modulated radiation therapy delivered as single-dose stereotactic radiosurgery (SRS). Previously published spinal SRS outcome analyses have included a heterogeneous population of cancer patients, mostly with short survival. This is the first study reporting the long-term tumor control and toxicity profiles after high-dose single-fraction spinal SRS. Methods and Materials: The study population included all patients treated from June 2004 to July 2009 with single-fraction spinal SRS (dose 24 Gy) who had survived at least 5 years after treatment. The endpoints examined included disease progression, surgical or radiation retreatment, in-field fracture development, and radiation-associated toxicity, scored using the Radiation Therapy Oncology Group radiation morbidity scoring criteria and the Common Terminology Criteria for Adverse Events, version 4.0. Local control and fracture development were assessed using Kaplan-Meier analysis. Results: Of 278 patients, 31 (11.1%), with 36 segments treated for spinal tumors, survived at least 5 years after treatment and were followed up radiographically and clinically for a median of 6.1 years (maximum 102 months). The histopathologic findings for the 5-year survivors included radiation-resistant metastases in 58%, radiation-sensitive metastases in 22%, and primary bone tumors in 19%. In this selected cohort, 3 treatment failures occurred at a median of 48.6 months, including 2 recurrences in the radiation field and 1 patient with demonstrated progression at the treatment margins. Ten lesions (27.8%) were associated with acute grade 1 cutaneous or gastrointestinal toxicity. Delayed toxicity ≥3 months after treatment included 8 cases (22.2%) of mild neuropathy, 2 (5.6%) of gastrointestinal discomfort, 8 (22.2%) of dermatitides, and 3 (8.3%) of myalgias/myositis. Thirteen

  2. Five-Year Outcomes of High-Dose Single-Fraction Spinal Stereotactic Radiosurgery

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    Moussazadeh, Nelson [Division of Neurological Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Department of Neurological Surgery, Weill Cornell Medical College, New York Presbyterian Hospital, New York, New York (United States); Lis, Eric [Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Katsoulakis, Evangelia [Department of Radiation Oncology, New York Methodist Hospital, Brooklyn, New York (United States); Kahn, Sweena; Svoboda, Marek; DiStefano, Natalie M.; McLaughlin, Lily [Division of Neurological Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Bilsky, Mark H. [Division of Neurological Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Department of Neurological Surgery, Weill Cornell Medical College, New York Presbyterian Hospital, New York, New York (United States); Yamada, Yoshiya [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Laufer, Ilya, E-mail: lauferi@mskcc.org [Division of Neurological Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Department of Neurological Surgery, Weill Cornell Medical College, New York Presbyterian Hospital, New York, New York (United States)

    2015-10-01

    Purpose: To characterize local tumor control and toxicity risk in very long-term survivors (>5 years) after high-dose spinal image guided, intensity modulated radiation therapy delivered as single-dose stereotactic radiosurgery (SRS). Previously published spinal SRS outcome analyses have included a heterogeneous population of cancer patients, mostly with short survival. This is the first study reporting the long-term tumor control and toxicity profiles after high-dose single-fraction spinal SRS. Methods and Materials: The study population included all patients treated from June 2004 to July 2009 with single-fraction spinal SRS (dose 24 Gy) who had survived at least 5 years after treatment. The endpoints examined included disease progression, surgical or radiation retreatment, in-field fracture development, and radiation-associated toxicity, scored using the Radiation Therapy Oncology Group radiation morbidity scoring criteria and the Common Terminology Criteria for Adverse Events, version 4.0. Local control and fracture development were assessed using Kaplan-Meier analysis. Results: Of 278 patients, 31 (11.1%), with 36 segments treated for spinal tumors, survived at least 5 years after treatment and were followed up radiographically and clinically for a median of 6.1 years (maximum 102 months). The histopathologic findings for the 5-year survivors included radiation-resistant metastases in 58%, radiation-sensitive metastases in 22%, and primary bone tumors in 19%. In this selected cohort, 3 treatment failures occurred at a median of 48.6 months, including 2 recurrences in the radiation field and 1 patient with demonstrated progression at the treatment margins. Ten lesions (27.8%) were associated with acute grade 1 cutaneous or gastrointestinal toxicity. Delayed toxicity ≥3 months after treatment included 8 cases (22.2%) of mild neuropathy, 2 (5.6%) of gastrointestinal discomfort, 8 (22.2%) of dermatitides, and 3 (8.3%) of myalgias/myositis. Thirteen

  3. Esophageal Toxicity From High-Dose, Single-Fraction Paraspinal Stereotactic Radiosurgery

    International Nuclear Information System (INIS)

    Cox, Brett W.; Jackson, Andrew; Hunt, Margie; Bilsky, Mark; Yamada, Yoshiya

    2012-01-01

    Purpose: To report the esophageal toxicity from single-fraction paraspinal stereotactic radiosurgery (SRS) and identify dosimetric and clinical risk factors for toxicity. Methods and Materials: A total of 204 spinal metastases abutting the esophagus (182 patients) were treated with high-dose single-fraction SRS during 2003-2010. Toxicity was scored using the National Cancer Institute Common Toxicity Criteria for Adverse Events, version 4.0. Dose-volume histograms were combined to generate a comprehensive atlas of complication incidence that identifies risk factors for toxicity. Correlation of dose-volume factors with esophageal toxicity was assessed using Fisher’s exact test and logistic regression. Clinical factors were correlated with toxicity. Results: The median dose to the planning treatment volume was 24 Gy. Median follow-up was 12 months (range, 3-81). There were 31 (15%) acute and 24 (12%) late esophageal toxicities. The rate of grade ≥3 acute or late toxicity was 6.8% (14 patients). Fisher’s exact test resulted in significant median splits for grade ≥3 toxicity at V12 = 3.78 cm 3 (relative risk [RR] 3.7, P=.05), V15 = 1.87 cm 3 (RR 13, P=.0013), V20 = 0.11 cm 3 (RR 6, P=0.01), and V22 = 0.0 cm 3 (RR 13, P=.0013). The median split for D2.5 cm 3 (14.02 Gy) was also a significant predictor of toxicity (RR 6; P=.01). A highly significant logistic regression model was generated on the basis of D2.5 cm 3 . One hundred percent (n = 7) of grade ≥4 toxicities were associated with radiation recall reactions after doxorubicin or gemcitabine chemotherapy or iatrogenic manipulation of the irradiated esophagus. Conclusions: High-dose, single-fraction paraspinal SRS has a low rate of grade ≥3 esophageal toxicity. Severe esophageal toxicity is minimized with careful attention to esophageal doses during treatment planning. Iatrogenic manipulation of the irradiated esophagus and systemic agents classically associated with radiation recall reactions are

  4. Single high-dose irradiation aggravates eosinophil-mediated fibrosis through IL-33 secreted from impaired vessels in the skin compared to fractionated irradiation

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    Lee, Eun-Jung, E-mail: forejs2@yuhs.ac [Department of Radiation Oncology, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Kim, Jun Won, E-mail: JUNWON@yuhs.ac [Department of Radiation Oncology, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Yoo, Hyun, E-mail: gochunghee@yuhs.ac [Department of Radiation Oncology, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Kwak, Woori, E-mail: asleo02@snu.ac.kr [Interdisciplinary Program in Bioinformatics, Seoul National University, Seoul 151-747 (Korea, Republic of); Choi, Won Hoon, E-mail: wonhoon@yuhs.ac [Department of Radiation Oncology, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Cho, Seoae, E-mail: seoae@cnkgenomics.com [C& K Genomics, Seoul National University Mt.4-2, Main Bldg. #514, SNU Research Park, NakSeoungDae, Gwanakgu, Seoul 151-919 (Korea, Republic of); Choi, Yu Jeong, E-mail: yunk9275@daum.net [Department of Radiation Oncology, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Lee, Yoon-Jin, E-mail: yjlee8@kirams.re.kr [Division of Radiation Effects, Research Center for Radiotherapy, Korea Institute of Radiological & Medical Sciences, Seoul 139-760 (Korea, Republic of); Cho, Jaeho, E-mail: jjhmd@yuhs.ac [Department of Radiation Oncology, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of)

    2015-08-14

    We have revealed in a porcine skin injury model that eosinophil recruitment was dose-dependently enhanced by a single high-dose irradiation. In this study, we investigated the underlying mechanism of eosinophil-associated skin fibrosis and the effect of high-dose-per-fraction radiation. The dorsal skin of a mini-pig was divided into two sections containing 4-cm{sup 2} fields that were irradiated with 30 Gy in a single fraction or 5 fractions and biopsied regularly over 14 weeks. Eosinophil-related Th2 cytokines such as interleukin (IL)-4, IL-5, and C–C motif chemokine-11 (CCL11/eotaxin) were evaluated by quantitative real-time PCR. RNA-sequencing using 30 Gy-irradiated mouse skin and functional assays in a co-culture system of THP-1 and irradiated-human umbilical vein endothelial cells (HUVECs) were performed to investigate the mechanism of eosinophil-mediated radiation fibrosis. Single high-dose-per-fraction irradiation caused pronounced eosinophil accumulation, increased profibrotic factors collagen and transforming growth factor-β, enhanced production of eosinophil-related cytokines including IL-4, IL-5, CCL11, IL-13, and IL-33, and reduced vessels compared with 5-fraction irradiation. IL-33 notably increased in pig and mouse skin vessels after single high-dose irradiation of 30 Gy, as well as in irradiated HUVECs following 12 Gy. Blocking IL-33 suppressed the migration ability of THP-1 cells and cytokine secretion in a co-culture system of THP-1 cells and irradiated HUVECs. Hence, high-dose-per-fraction irradiation appears to enhance eosinophil-mediated fibrotic responses, and IL-33 may be a key molecule operating in eosinophil-mediated fibrosis in high-dose-per fraction irradiated skin. - Highlights: • Single high-dose irradiation aggravates eosinophil-mediated fibrosis through IL-33. • Vascular endothelial cells damaged by high-dose radiation secrete IL-33. • Blocking IL-33 suppressed migration of inflammatory cells and cytokine secretion. • IL

  5. Single high-dose irradiation aggravates eosinophil-mediated fibrosis through IL-33 secreted from impaired vessels in the skin compared to fractionated irradiation

    International Nuclear Information System (INIS)

    Lee, Eun-Jung; Kim, Jun Won; Yoo, Hyun; Kwak, Woori; Choi, Won Hoon; Cho, Seoae; Choi, Yu Jeong; Lee, Yoon-Jin; Cho, Jaeho

    2015-01-01

    We have revealed in a porcine skin injury model that eosinophil recruitment was dose-dependently enhanced by a single high-dose irradiation. In this study, we investigated the underlying mechanism of eosinophil-associated skin fibrosis and the effect of high-dose-per-fraction radiation. The dorsal skin of a mini-pig was divided into two sections containing 4-cm 2 fields that were irradiated with 30 Gy in a single fraction or 5 fractions and biopsied regularly over 14 weeks. Eosinophil-related Th2 cytokines such as interleukin (IL)-4, IL-5, and C–C motif chemokine-11 (CCL11/eotaxin) were evaluated by quantitative real-time PCR. RNA-sequencing using 30 Gy-irradiated mouse skin and functional assays in a co-culture system of THP-1 and irradiated-human umbilical vein endothelial cells (HUVECs) were performed to investigate the mechanism of eosinophil-mediated radiation fibrosis. Single high-dose-per-fraction irradiation caused pronounced eosinophil accumulation, increased profibrotic factors collagen and transforming growth factor-β, enhanced production of eosinophil-related cytokines including IL-4, IL-5, CCL11, IL-13, and IL-33, and reduced vessels compared with 5-fraction irradiation. IL-33 notably increased in pig and mouse skin vessels after single high-dose irradiation of 30 Gy, as well as in irradiated HUVECs following 12 Gy. Blocking IL-33 suppressed the migration ability of THP-1 cells and cytokine secretion in a co-culture system of THP-1 cells and irradiated HUVECs. Hence, high-dose-per-fraction irradiation appears to enhance eosinophil-mediated fibrotic responses, and IL-33 may be a key molecule operating in eosinophil-mediated fibrosis in high-dose-per fraction irradiated skin. - Highlights: • Single high-dose irradiation aggravates eosinophil-mediated fibrosis through IL-33. • Vascular endothelial cells damaged by high-dose radiation secrete IL-33. • Blocking IL-33 suppressed migration of inflammatory cells and cytokine secretion. • IL-33

  6. Comparison of Different Fractionation Schedules Toward a Single Fraction in High-Dose-Rate Brachytherapy as Monotherapy for Low-Risk Prostate Cancer Using 3-Dimensional Radiobiological Models

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    Mavroidis, Panayiotis, E-mail: mavroidis@uthscsa.edu [Department of Radiation Oncology, University of Texas Health Sciences Center, San Antonio, Texas (United States); Department of Medical Radiation Physics, Karolinska Institutet and Stockholm University, Stockholm (Sweden); Milickovic, Natasa [Department of Medical Physics and Engineering, Strahlenklinik, Klinikum Offenbach GmbH, Offenbach (Germany); Cruz, Wilbert F. [Department of Radiation Oncology, University of Texas Health Sciences Center, San Antonio, Texas (United States); Tselis, Nikolaos [Strahlenklinik, Klinikum Offenbach GmbH, Offenbach (Germany); Karabis, Andreas [Pi-Medical Ltd., Athens (Greece); Stathakis, Sotirios; Papanikolaou, Nikos [Department of Radiation Oncology, University of Texas Health Sciences Center, San Antonio, Texas (United States); Zamboglou, Nikolaos [Strahlenklinik, Klinikum Offenbach GmbH, Offenbach (Germany); Baltas, Dimos [Department of Medical Physics and Engineering, Strahlenklinik, Klinikum Offenbach GmbH, Offenbach (Germany); Nuclear and Particle Physics Section, Physics Department, University of Athens, Athens (Greece)

    2014-01-01

    Purpose: The aim of the present study was the investigation of different fractionation schemes to estimate their clinical impact. For this purpose, widely applied radiobiological models and dosimetric measures were used to associate their results with clinical findings. Methods and Materials: The dose distributions of 12 clinical high-dose-rate brachytherapy implants for prostate were evaluated in relation to different fractionation schemes. The fractionation schemes compared were: (1) 1 fraction of 20 Gy; (2) 2 fractions of 14 Gy; (3) 3 fractions of 11 Gy; and (4) 4 fractions of 9.5 Gy. The clinical effectiveness of the different fractionation schemes was estimated through the complication-free tumor control probability (P{sub +}), the biologically effective uniform dose, and the generalized equivalent uniform dose index. Results: For the different fractionation schemes, the tumor control probabilities were 98.5% in 1 × 20 Gy, 98.6% in 2 × 14 Gy, 97.5% in 3 × 11 Gy, and 97.8% in 4 × 9.5 Gy. The corresponding P{sub +} values were 88.8% in 1 × 20 Gy, 83.9% in 2 × 14 Gy, 86.0% in 3 × 11 Gy, and 82.3% in 4 × 9.5 Gy. With use of the fractionation scheme 4 × 9.5 Gy as reference, the isoeffective schemes regarding tumor control for 1, 2, and 3 fractions were 1 × 19.68 Gy, 2 × 13.75 Gy, and 3 × 11.05 Gy. The optimum fractionation schemes for 1, 2, 3, and 4 fractions were 1 × 19.16 Gy with a P{sub +} of 91.8%, 2 × 13.2 Gy with a P{sub +} of 89.6%, 3 × 10.6 Gy with a P{sub +} of 88.4%, and 4 × 9.02 Gy with a P{sub +} of 86.9%. Conclusions: Among the fractionation schemes 1 × 20 Gy, 2 × 14 Gy, 3 × 11 Gy, and 4 × 9.5 Gy, the first scheme was more effective in terms of P{sub +}. After performance of a radiobiological optimization, it was shown that a single fraction of 19.2 to 19.7 Gy (average 19.5 Gy) should produce at least the same benefit as that given by the 4 × 9.5 Gy scheme, and it should reduce the expected total complication probability by

  7. High-Dose, Single-Fraction Irradiation Rapidly Reduces Tumor Vasculature and Perfusion in a Xenograft Model of Neuroblastoma

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    Jani, Ashish; Shaikh, Fauzia; Barton, Sunjay [Department of Radiation Oncology, Columbia University Medical Center, New York, New York (United States); Willis, Callen [Department of Surgery, Columbia University Medical Center, New York, New York (United States); Banerjee, Debarshi [Department of Pediatrics, Columbia University Medical Center, New York, New York (United States); Mitchell, Jason [Department of Surgery, Columbia University Medical Center, New York, New York (United States); Hernandez, Sonia L. [Department of Surgery, University of Chicago, Chicago, Illinois (United States); Hei, Tom [Department of Radiation Oncology, Columbia University Medical Center, New York, New York (United States); Kadenhe-Chiweshe, Angela [Department of Surgery, Columbia University Medical Center, New York, New York (United States); Yamashiro, Darrell J. [Department of Surgery, Columbia University Medical Center, New York, New York (United States); Department of Pediatrics, Columbia University Medical Center, New York, New York (United States); Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York (United States); Connolly, Eileen P., E-mail: epc2116@cumc.columbia.edu [Department of Radiation Oncology, Columbia University Medical Center, New York, New York (United States)

    2016-04-01

    Purpose: To characterize the effects of high-dose radiation therapy (HDRT) on neuroblastoma tumor vasculature, including the endothelial cell (EC)–pericyte interaction as a potential target for combined treatment with antiangiogenic agents. Methods and Materials: The vascular effects of radiation therapy were examined in a xenograft model of high-risk neuroblastoma. In vivo 3-dimensional contrast-enhanced ultrasonography (3D-CEUS) imaging and immunohistochemistry (IHC) were performed. Results: HDRT significantly reduced tumor blood volume 6 hours after irradiation compared with the lower doses used in conventionally fractionated radiation. There was a 63% decrease in tumor blood volume after 12-Gy radiation compared with a 24% decrease after 2 Gy. Analysis of tumor vasculature by lectin angiography showed a significant loss of small vessel ends at 6 hours. IHC revealed a significant loss of ECs at 6 and 72 hours after HDRT, with an accompanying loss of immature and mature pericytes at 72 hours. Conclusions: HDRT affects tumor vasculature in a manner not observed at lower doses. The main observation was an early reduction in tumor perfusion resulting from a reduction of small vessel ends with a corresponding loss of endothelial cells and pericytes.

  8. Fractionated stereotactic radiation therapy and single high-dose radiosurgery for acoustic neuroma: early results of a prospective clinical study

    International Nuclear Information System (INIS)

    Meijer, O.W.M.; Wolbers, J.G.; Baayen, J.C.; Slotman, B.J.

    2000-01-01

    Purpose: To prospectively assess the local control and toxicity rate in acoustic neuroma patients treated with linear accelerator-based radiosurgery and fractionated stereotactic radiation therapy. Methods and Materials: We evaluated 37 consecutive patients treated with stereotactic radiation therapy for acoustic neuroma. All patients had progressive tumors, progressive symptoms, or both. Mean tumor diameter was 2.3 cm (range 0.8-3.3) on magnetic resonance (MR) scan. Dentate patients were given a dose of 5 x 4 Gy or 5 x 5 Gy and edentate patients were given a dose of 1 x 10 Gy or 1 x 12.50 Gy prescribed to the 80% isodose. All patients were treated with a single isocenter. Results: With a mean follow-up period of 25 months (range 12-61), the actuarial local control rate at 5 years was 91% (only 1 patient failed). The actuarial rate of hearing preservation at 5 years was 66% in previously-hearing patients. The actuarial rate of freedom from trigeminal nerve toxicity was 97% at 5 years. No patient developed facial nerve toxicity or other complications. Conclusion: In this unselected series, fractionated stereotactic radiation therapy and linear accelerator-based radiosurgery give excellent local control in acoustic neuroma. It combines a high rate of preservation of hearing with a very low rate of other toxicity, although follow-up is relatively short

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

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    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.

  10. Phase I/II trial of single-fraction high-dose-rate brachytherapy-boosted hypofractionated intensity-modulated radiation therapy for localized adenocarcinoma of the prostate.

    Science.gov (United States)

    Myers, Michael A; Hagan, Michael P; Todor, Dorin; Gilbert, Lynn; Mukhopadhyay, Nitai; Randolf, Jessica; Heimiller, Jeffrey; Anscher, Mitchell S

    2012-01-01

    A Phase I/II protocol was conducted to examine the toxicity and efficacy of the combination of intensity-modulated radiation therapy (IMRT) with a single-fraction high-dose-rate (HDR) brachytherapy implant. From 2001 through 2006, 26 consecutive patients were treated on the trial. The primary objective was to demonstrate a high rate of completion without experiencing a treatment-limiting toxicity. Eligibility was limited to patients with T stage ≤2b, prostate-specific antigen (PSA) ≤20, and Gleason score ≤7. Treatment began with a single HDR fraction of 6Gy to the entire prostate and 9Gy to the peripheral zone, followed by IMRT optimized to deliver in 28 fractions with a normalized total dose of 70Gy. Patients received 50.4Gy to the pelvic lymph node. The prostate dose (IMRT and HDR) resulted in an average biologic equivalent dose >128Gy (α/β=3). Patients whose pretreatment PSA was ≥10ng/mL, Gleason score 7, or stage ≥T2b received short-term androgen ablation. Median followup was 53 months (9-68 months). There were no biochemical failures by either the American Society of Therapeutic Radiology and Oncology or the Phoenix definitions. The median nadir PSA was 0.32ng/mL. All the 26 patients completed the treatment as prescribed. The rate of Grade 3 late genitourinary toxicity was 3.8% consisting of a urethral stricture. There was no other Grade 3 or 4 genitourinary or gastrointestinal toxicities. Single-fraction HDR-boosted IMRT is a safe effective method of dose escalation for localized prostate cancer. Copyright © 2012 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  11. High-Dose-Rate Brachytherapy of a Single Implant With Two Fractions Combined With External Beam Radiotherapy for Hormone-Naive Prostate Cancer

    International Nuclear Information System (INIS)

    Sato, Morio; Mori, Takashi; Shirai, Shintaro; Kishi, Kazushi; Inagaki, Takeshi; Hara, Isao

    2008-01-01

    Purpose: To evaluate the preliminary outcomes of high-dose-rate (HDR) brachytherapy of a single implant with two fractions and external beam radiotherapy (EBRT) for hormone-naive prostate cancer. Methods and Materials: Between March 2000 and Sept 2003, a total of 53 patients with tumor Stage T1c-T3b N0 M0 prostate cancer were treated with HDR brachytherapy boost doses (7.5 Gy/fraction) and 50-Gy EBRT during a 5.5-week period. Median follow-up was 61 months. Patients were divided into groups with localized (T1c-T2b) and advanced disease (T3a-T3b). We used the American Society for Therapeutic Radiology and Oncology (ASTRO) definition for biochemical failure. According to recommendations of the Radiation Therapy Oncology Group-ASTRO Phoenix Consensus Conference, biochemical failure-free control rates (BF-FCRs) at 3 years were investigated as 2 years short of the median follow-up. Results: Between April 2000 and Sept 2007, Common Terminology Criteria for Adverse Events Version 2.0 late Grade 2 genitourinary and gastrointestinal toxicity rates were 0% and 3.8%, respectively. Erectile preservation was 25% at 5 years. Overall survival was 88.1% and cause-specific survival was 100%. At 3 years, ASTRO BF-FCRs of the localized and advanced groups were 100% and 42%, respectively (p = 0.001). Conclusions: The HDR brachytherapy of a single implant with two fractions plus EBRT is effective in treating patients with localized hormone-naive prostate cancer, with the least genitourinary and gastrointestinal toxicities; however, longer median BF-FCR follow-up is required to assess these findings

  12. Health-Related Quality of Life After Single-Fraction High-Dose-Rate Brachytherapy and Hypofractionated External Beam Radiotherapy for Prostate Cancer

    International Nuclear Information System (INIS)

    Morton, Gerard C.; Loblaw, D. Andrew; Chung, Hans; Tsang, Gail; Sankreacha, Raxa; Deabreu, Andrea; Zhang Liying; Mamedov, Alexandre; Cheung, Patrick; Batchelar, Deidre; Danjoux, Cyril; Szumacher, Ewa

    2011-01-01

    Purpose: To investigate the change in health-related quality of life for men after high-dose-rate brachytherapy and external beam radiotherapy for prostate cancer and the factors associated with this change. Methods and Materials: Eligible patients had clinically localized intermediate-risk prostate cancer. The patients received high-dose-rate brachytherapy as a single 15-Gy implant, followed by external beam radiotherapy to 37.5 Gy in 15 fractions. The patients were monitored prospectively for toxicity (Common Terminology Criteria for Adverse Events, version 3.0) and health-related quality of life (Expanded Prostate Cancer Index Composite [EPIC]). The proportion of patients developing a clinically significant difference in the EPIC domain score (minimally important difference of >0.5 standard deviation) was determined and correlated with the baseline clinical and dosimetric factors. The study accrued 125 patients, with a median follow-up of 24 months. Results: By 24 months, 23% had Grade 2 urinary toxicity and only 5% had Grade 2 bowel toxicity, with no Grade 3 toxicity. The proportion of patients reporting a significant decrease in EPIC urinary, bowel, sexual, and hormonal domain scores was 53%, 51%, 45%, and 40% at 12 months and 57%, 65%, 51%, and 30% at 24 months, respectively. The proportion with a >1 standard deviation decrease in the EPIC urinary, bowel, sexual, and hormonal domain scores was 38%, 36%, 24%, and 20% at 12 months and 46%, 48%, 19%, and 8% at 24 months, respectively. On multivariate analysis, the dose to 10% of the urethra was associated with a decreasing EPIC urinary domain score (p = .0089) and, less strongly (p = .0312) with a decreasing hormonal domain score. No association was found between the prostate volume, bladder dose, or high-dose volume and urinary health-related quality of life. A high baseline International Index of Erectile Function score was associated (p = .0019) with a decreasing sexual domain score. The optimal maximal dose

  13. In vivo assessment of the gastric mucosal tolerance dose after single fraction, small volume irradiation of liver malignancies by computed tomography-guided, high-dose-rate brachytherapy

    International Nuclear Information System (INIS)

    Streitparth, Florian; Pech, Maciej; Boehmig, Michael; Ruehl, Ricarda; Peters, Nils; Wieners, Gero; Steinberg, Johannes; Lopez-Haenninen, Enrique; Felix, Roland; Wust, Peter; Ricke, Jens

    2006-01-01

    Purpose: The aim of this study was to assess the tolerance dose of gastric mucosa for single-fraction computed tomography (CT)-guided, high-dose-rate (HDR) brachytherapy of liver malignancies. Methods and Materials: A total of 33 patients treated by CT-guided HDR brachytherapy of liver malignancies in segments II and/or III were included. Dose planning was performed upon a three-dimensional CT data set acquired after percutaneous applicator positioning. All patients received gastric protection post-treatment. For further analysis, the contours of the gastric wall were defined in every CT slice using Brachyvision Software. Dose-volume histograms were calculated for each treatment and correlated with clinical data derived from questionnaires assessing Common Toxicity Criteria (CTC). All patients presenting symptoms of upper GI toxicity were examined endoscopically. Results: Summarizing all patients the minimum dose applied to 1 ml of the gastric wall (D 1ml ) ranged from 6.3 to 34.2 Gy; median, 14.3 Gy. Toxicity was present in 18 patients (55%). We found nausea in 16 (69%), emesis in 9 (27%), cramping in 13 (39%), weight loss in 12 (36%), gastritis in 4 (12%), and ulceration in 5 patients (15%). We found a threshold dose D 1ml of 11 Gy for general gastric toxicity and 15.5 Gy for gastric ulceration verified by an univariate analysis (p = 0.01). Conclusions: For a single fraction, small volume irradiation we found in the upper abdomen a threshold dose D 1ml of 15.5 Gy for the clinical endpoint ulceration of the gastric mucosa. This in vivo assessment is in accordance with previously published tolerance data

  14. Single-Fraction High-Dose-Rate Brachytherapy and Hypofractionated External Beam Radiation Therapy in the Treatment of Intermediate-Risk Prostate Cancer - Long Term Results

    Energy Technology Data Exchange (ETDEWEB)

    Cury, Fabio L., E-mail: fabio.cury@muhc.mcgill.ca [Department of Radiation Oncology, McGill University Health Centre, Montreal, QC (Canada); Duclos, Marie [Department of Radiation Oncology, McGill University Health Centre, Montreal, QC (Canada); Aprikian, Armen [Department of Urology, McGill University Health Centre, Montreal, QC (Canada); Patrocinio, Horacio [Department of Medical Physics, McGill University Health Centre, Montreal, QC (Canada); Kassouf, Wassim [Department of Urology, McGill University Health Centre, Montreal, QC (Canada); Shenouda, George; Faria, Sergio; David, Marc; Souhami, Luis [Department of Radiation Oncology, McGill University Health Centre, Montreal, QC (Canada)

    2012-03-15

    Purpose: 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). Methods and Materials: 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. Results: 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. Conclusion: 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.

  15. In vivo assessment of catheter positioning accuracy and prolonged irradiation time on liver tolerance dose after single-fraction 192Ir high-dose-rate brachytherapy

    Directory of Open Access Journals (Sweden)

    Kropf Siegfried

    2011-09-01

    Full Text Available Abstract Background To assess brachytherapy catheter positioning accuracy and to evaluate the effects of prolonged irradiation time on the tolerance dose of normal liver parenchyma following single-fraction irradiation with 192 Ir. Materials and methods Fifty patients with 76 malignant liver tumors treated by computed tomography (CT-guided high-dose-rate brachytherapy (HDR-BT were included in the study. The prescribed radiation dose was delivered by 1 - 11 catheters with exposure times in the range of 844 - 4432 seconds. Magnetic resonance imaging (MRI datasets for assessing irradiation effects on normal liver tissue, edema, and hepatocyte dysfunction, obtained 6 and 12 weeks after HDR-BT, were merged with 3D dosimetry data. The isodose of the treatment plan covering the same volume as the irradiation effect was taken as a surrogate for the liver tissue tolerance dose. Catheter positioning accuracy was assessed by calculating the shift between the 3D center coordinates of the irradiation effect volume and the tolerance dose volume for 38 irradiation effects in 30 patients induced by catheters implanted in nearly parallel arrangement. Effects of prolonged irradiation were assessed in areas where the irradiation effect volume and tolerance dose volume did not overlap (mismatch areas by using a catheter contribution index. This index was calculated for 48 irradiation effects induced by at least two catheters in 44 patients. Results Positioning accuracy of the brachytherapy catheters was 5-6 mm. The orthogonal and axial shifts between the center coordinates of the irradiation effect volume and the tolerance dose volume in relation to the direction vector of catheter implantation were highly correlated and in first approximation identically in the T1-w and T2-w MRI sequences (p = 0.003 and p p = 0.001 and p = 0.004, respectively. There was a significant shift of the irradiation effect towards the catheter entry site compared with the planned dose

  16. Colon mucosal cells after high-dose fractional irradiation

    International Nuclear Information System (INIS)

    Zorc-Pleskovic, R.; Vraspir-Porenta, O.; Petrovic, D.; Zorc, M.; Pleskovic, L.

    2000-01-01

    The aim of this study was to investigate histological and stereological changes in cryptal enterocytes, mucosal lymphocytes and mast cells 10 days after irradiation. For experimental model, 24 Beagle dogs 1-2 years old were used. Twelve dogs were irradiated 20 days with 32 Gy over the whole pelvis and tail. Another 12 dogs represented a control group. For the detection of apoptosis, the TUNEL technique was used. Histological and stereological analyses were performed using a Wild sampling microscope M 1000. In the irradiated group, volume density (P < 0.01), numerical density (P < 0.05) and average volume of lymphocytes (P < 0.001) were significantly lower than in the nonirradiated group. Numerical areal density of mast cells in the irradiated group was also significantly lower (P < 0.05). Volume density (P < 0.001) and average volume of mast cells (P < 0.001) were significantly higher in the irradiated group. The results of our experiments show that irradiation causes injury and loss of lymphocytes and mast cells in the colon mucosa. Apoptosis was detected in enterocytes and lymphocytes in the irradiated group and in nonirradiated group in equal numbers (2.5 ± 0.3 vs. 2.3 ± 0.3; ns.), suggesting that 10 days after high-dose irradiation, the cell loss is not due to apoptosis. (author)

  17. High dose per fraction dosimetry of small fields with Gafchromic EBT2 film

    International Nuclear Information System (INIS)

    Hardcastle, Nicholas; Basavatia, Amar; Bayliss, Adam; Tome, Wolfgang A.

    2011-01-01

    Purpose: Small field dosimetry is prone to uncertainties due to the lack of electronic equilibrium and the use of the correct detector size relative to the field size measured. It also exhibits higher sensitivity to setup errors as well as large variation in output with field size and shape. Radiochromic film is an attractive method for reference dosimetry in small fields due to its ability to provide 2D dose measurements while having minimal impact on the dose distribution. Gafchromic EBT2 has a dose range of up to 40 Gy; therefore, it could potentially be useful for high dose reference dosimetry with high spatial resolution. This is a requirement in stereotactic radiosurgery deliveries, which deliver high doses per fraction to small targets. Methods: Targets of 4 mm and 12 mm diameters were treated to a minimum peripheral dose of 21 Gy prescribed to 80% of the maximum dose in one fraction. Target doses were measured with EBT2 film (both targets) and an ion chamber (12 mm target only). Measured doses were compared with planned dose distributions using profiles through the target and minimum peripheral dose coverage. Results: The measured target doses and isodose coverage agreed with the planned dose within ±1 standard deviation of three measurements, which were 2.13% and 2.5% for the 4 mm and 12 mm targets, respectively. Conclusions: EBT2 film is a feasible dosimeter for high dose per fraction reference 2D dosimetry.

  18. Radiobiological aspects of continuous low dose-rate irradiation and fractionated high dose-rate irradiation

    International Nuclear Information System (INIS)

    Turesson, I.

    1990-01-01

    The biological effects of continuous low dose-rate irradiation and fractionated high dose-rate irradiation in interstitial and intracavitary radiotherapy and total body irradiation are discussed in terms of dose-rate fractionation sensitivity for various tissues. A scaling between dose-rate and fraction size was established for acute and late normal-tissue effects which can serve as a guideline for local treatment in the range of dose rates between 0.02 and 0.005 Gy/min and fraction sizes between 8.5 and 2.5 Gy. This is valid provided cell-cycle progression and proliferation can be ignored. Assuming that the acute and late tissue responses are characterized by α/β values of about 10 and 3 Gy and a mono-exponential repair half-time of about 3 h, the same total doses given with either of the two methods are approximately equivalent. The equivalence for acute and late non-hemopoietic normal tissue damage is 0.02 Gy/min and 8.5 Gy per fraction; 0.01 Gy/min and 5.5 Gy per fraction; and 0.005 Gy/min and 2.5Gy per fraction. A very low dose rate, below 0.005 Gy/min, is thus necessary to simulate high dose-rate radiotherapy with fraction sizes of about 2Gy. The scaling factor is, however, dependent on the repair half-time of the tissue. A review of published data on dose-rate effects for normal tissue response showed a significantly stronger dose-rate dependence for late than for acute effects below 0.02 Gy/min. There was no significant difference in dose-rate dependence between various acute non-hemopoietic effects or between various late effects. The consistent dose-rate dependence, which justifies the use of a general scaling factor between fraction size and dose rate, contrasts with the wide range of values for repair half-time calculated for various normal-tissue effects. This indicates that the model currently used for repair kinetics is not satisfactory. There are also few experimental data in the clinical dose-rate range, below 0.02 Gy/min. It is therefore

  19. High-Dose-Rate Brachytherapy Boost for Prostate Cancer: Comparison of Two Different Fractionation Schemes

    International Nuclear Information System (INIS)

    Kaprealian, Tania; Weinberg, Vivian; Speight, Joycelyn L.; Gottschalk, Alexander R.; Roach, Mack; Shinohara, Katsuto; Hsu, I.-Chow

    2012-01-01

    Purpose: This is a retrospective study comparing our experience with high-dose-rate (HDR) brachytherapy boost for prostate cancer, using two different fractionation schemes, 600 cGy × 3 fractions (patient group 1) and 950 cGy × 2 fractions (patient group 2). Methods and Materials: A total of 165 patients were treated for prostate cancer using external beam radiation therapy up to a dose of 45 Gy, followed by an HDR brachytherapy prostate radiation boost. Between July 1997 and Nov 1999, 64 patients were treated with an HDR boost of 600 cGy × 3 fractions; and between June 2000 and Nov 2005, 101 patients were treated with an HDR boost of 950 cGy × 2 fractions. All but 9 patients had at least one of the following risk features: pretreatment prostate-specific antigen (PSA) level >10, a Gleason score ≥7, and/or clinical stage T3 disease. Results: Median follow-up was 105 months for group 1 and 43 months for group 2. Patients in group 2 had a greater number of high-risk features than group 1 (p = 0.02). Adjusted for comparable follow-up, there was no difference in biochemical no-evidence-of-disease (bNED) rate between the two fractionation scheme approaches, with 5-year Kaplan-Meier estimates of 93.5% in group 1 and 87.3% in group 2 (p = 0.19). The 5-year estimates of progression-free survival were 86% for group 1 and 83% for group 2 (p = 0.53). Among high-risk patients, there were no differences in bNED or PFS rate due to fractionation. Conclusions: Results were excellent for both groups. Adjusted for comparable follow-up, no differences were found between groups.

  20. Fractional model for pharmacokinetics of high dose methotrexate in children with acute lymphoblastic leukaemia

    Science.gov (United States)

    Popović, Jovan K.; Spasić, Dragan T.; Tošić, Jela; Kolarović, Jovanka L.; Malti, Rachid; Mitić, Igor M.; Pilipović, Stevan; Atanacković, Teodor M.

    2015-05-01

    The aim of this study is to promote a model based on the fractional differential calculus related to the pharmacokinetic individualization of high dose methotrexate treatment in children with acute lymphoblastic leukaemia, especially in high risk patients. We applied two-compartment fractional model on 8 selected cases with the largest number (4-19) of measured concentrations, among 43 pediatric patients received 24-h methotrexate 2-5 g/m2 infusions. The plasma concentrations were determined by fluorescence polarization immunoassay. Our mathematical procedure, designed by combining Post's and Newton's method, was coded in Mathematica 8.0 and performed on Fujicu Celsius M470-2 PC. Experimental data show that most of the measured values of methotrexate were in decreasing order. However, in certain treatments local maximums were detected. On the other hand, integer order compartmental models do not give values which fit well with the observed data. By the use of our model, we obtained better results, since it gives more accurate behavior of the transmission, as well as the local maximums which were recognized in methotrexate monitoring. It follows from our method that an additional test with a small methotrexate dose can be suggested for the fractional system parameter identification and the prediction of a possible pattern with a full dose in the case of high risk patients. A special feature of the fractional model is that it can also recognize and better fit an observed non-monotonic behavior. A new parameter determination procedure can be successfully used.

  1. Allogeneic bone marrow transplantation in adults after fractionated body irradiation and high dose cyclophosphamide

    International Nuclear Information System (INIS)

    Brinch, L.; Evensen, S.A.; Albrechtsen, D.; Egeland, T.; Solheim, B.G.; Rollag, H.; Naalsund, A.; Jacobsen, A.B.

    1991-01-01

    The authors present short and long-term results of allogeneic bone marrow transplantation after hyper-fractionated total body irradiation and high dose cyclophosphamide in ten patients treated for leukaemia during th period 1985-89. Three patients died from complications connected to the transplantation, while seven are living free from leukaemia 18 to 59 months after transplantation. Two patients need treatment for chronic graft versus host disease. Allogeneic bone marrow transplantation is expensive and risky. Close cooperation between clinicians and laboratory specialists is essential. The treatment increases long term survival and probably cures certain patients with leukaemia. Some of the patients will need treatment for chronic graft versus host disease and other late sequelae. 19 refs., 2 tabs

  2. The effects of high dose and highly fractionated radiation on distraction osteogenesis in the murine mandible

    International Nuclear Information System (INIS)

    Monson, Laura A; Cavaliere, Christi M; Deshpande, Sagar S; Ayzengart, Alexander L; Buchman, Steven R

    2012-01-01

    The ability of irradiated tissue to support bony growth remains poorly defined, although there are anecdotal cases reported showing mixed results for the use of mandibular distraction osteogenesis after radiation for head and neck cancer. Many of these reports lack objective measures that would allow adequate analysis of outcomes or efficacy. The purpose of this experiment was to utilize a rat model of mandibular distraction osteogenesis after high dose and highly fractionated radiation therapy and to evaluate and quantify distracted bone formation under these conditions. Male Sprague–Dawley rats underwent 12 fractions of external beam radiation (48 Gray) of the left mandible. Following a two week recovery period, an external frame distractor was applied and gradual distraction of the mandible was performed. Tissue was harvested after a twenty-eight day consolidation period. Gross, radiologic and histological evaluations were undertaken. Those animals subjected to pre-operative radiation showed severe attenuation of bone formation including bone atrophy, incomplete bridging of the distraction gap, and gross bony defects or non-union. Although physical lengthening was achieved, the irradiated bone consistently demonstrated marked damaging effects on the normal process of distraction osteogenesis. This murine model has provided reliable evidence of the injurious effects of high dose radiation on bone repair and regeneration in distraction osteogenesis utilizing accurate and reproducible metrics. These results can now be used to assist in the development of therapies directed at mitigating the adverse consequences of radiation on the regeneration of bone and to optimize distraction osteogenesis so it can be successfully applied to post-oncologic reconstruction

  3. Fractionated high dose rate intraluminal brachytherapy in palliation of advanced esophageal cancer

    International Nuclear Information System (INIS)

    Sur, Ranjan K.; Donde, Bernard; Levin, Victor C.; Mannell, Aylwyn

    1998-01-01

    Purpose: To optimize the dose of fractionated brachytherapy for palliation of advanced esophageal cancer. Methods and Materials: One hundred and seventy-two patients with advanced esophageal cancer were randomized to receive 12 Gy/2 fractions (group A); 16 Gy/2 fractions (group B), and 18 Gy/3 fractions (group C) by high dose rate intraluminal brachytherapy (HDRILBT). Treatment was given weekly and dose prescribed at 1 cm from the source axis. Patients were followed up monthly and assessed for dysphagia relief and development of complications. Results: Twenty-two patients died before completing treatment due to advanced disease and poor general condition. The overall survival was 19.4% at the end of 12 months for the whole group (A--9.8%, B--22.46%, C--35.32%; p > 0.05). The dysphagia-free survival was 28.9% at 12 months for the whole group (A--10.8%, B--25.43%, C--38.95%; p > 0.05). Forty-three patients developed fibrotic strictures needing dilatation (A--5 of 35, B--15 of 60, C--23 of 55; p = 0.032). Twenty-seven patients had persistent luminal disease (A--11, B--6, C--10), 15 of which progressed to fistulae (A--7, B--2, C--6; p = 0.032). There was no effect of age, sex, race, histology, performance status, previous dilation, presenting dysphagia score, presenting weight, grade, tumor length, and stage on overall survival, dysphagia-free, and complication-free survival (p > 0.05). On a multivariate analysis, brachytherapy dose (p = 0.002) and tumor length (p = 0.0209) were found to have a significant effect on overall survival; brachytherapy dose was the only factor that had an impact on local tumor control (p = 0.0005), while tumor length was the only factor that had an effect on dysphagia-free survival (p = 0.0475). When compared to other forms of palliation currently available (bypass surgery, laser, chemotherapy, intubation, external radiotherapy), fractionated brachytherapy gave the best results with a median survival of 6.2 months. Conclusions: Fractionated

  4. Justification for inter-fraction correction of catheter movement in fractionated high dose-rate brachytherapy treatment of prostate cancer

    International Nuclear Information System (INIS)

    Simnor, Tania; Li, Sonia; Lowe, Gerry; Ostler, Peter; Bryant, Linda; Chapman, Caroline; Inchley, Dave; Hoskin, Peter J.

    2009-01-01

    Background and purpose: Fractionated high dose-rate (HDR) brachytherapy in the treatment of prostate cancer relies on reproducible catheter positions for each fraction to ensure adequate tumour coverage while minimising dose to normal tissues. Peri-prostatic oedema may cause caudal displacement of the catheters relative to the prostate gland between fractions. This can be corrected for by changing source dwell positions or by physical re-advancement of catheters before treatment. Materials and methods: Data for 20 consecutive monotherapy patients receiving three HDR fractions of 10.5 Gy per fraction over 2 days were analysed retrospectively. Pre-treatment CT scans were used to assess the effect of catheter movement between fractions on implant quality, with and without movement correction. Implant quality was evaluated using dosimetric parameters. Results: Compared to the first fraction (f1) the mean inter-fraction caudal movement relative to the prostate base was 7.9 mm (f2) (range 0-21 mm) and 3.9 mm (f3) (range 0-25.5 mm). PTV D90% was reduced without movement correction by a mean of 27.8% (f2) and 32.3% (f3), compared with 5.3% and 5.1%, respectively, with catheter movement correction. Dose to 2 cc of the rectum increased by a mean of 0.69 (f2) and 0.76 Gy (f3) compared with an increase of 0.03 and 0.04 Gy, respectively, with correction. The urethra V12 also increased by a mean of 0.36 (f2) and 0.39 Gy (f3) compared with 0.06 and 0.16 Gy, respectively, with correction. Conclusions: Inter-fraction correction for catheter movement using pre-treatment imaging is critical to maintain the quality of an implant. Without movement correction there is significant risk of tumour under-dosage and normal tissue over-dosage. The findings of this study justify additional imaging between fractions in order to carry out correction.

  5. Neuropsychological function in adults after high dose fractionated radiation therapy of skull base tumors

    International Nuclear Information System (INIS)

    Glosser, Guila; McManus, Pat; Munzenrider, John; Austin-Seymour, Mary; Fullerton, Barbara; Adams, Judy; Urie, Marcia M.

    1997-01-01

    Purpose: To evaluate the long term effects of high dose fractionated radiation therapy on brain functioning prospectively in adults without primary brain tumors. Methods and Materials: Seventeen patients with histologically confirmed chordomas and low grade chondrosarcomas of the skull base were evaluated with neuropsychological measures of intelligence, language, memory, attention, motor function and mood following surgical resection/biopsy of the tumor prior to irradiation, and then at about 6 months, 2 years and 4 years following completion of treatment. None received chemotherapy. Results: In the patients without tumor recurrence or radiation necrosis, there were no indications of adverse effects on cognitive functioning in the post-acute through the late stages after brain irradiation. Even in patients who received doses of radiation up to 66 Cobalt Gy equivalent through nondiseased (temporal lobe) brain tissue, memory and cognitive functioning remained stable for up to 5 years after treatment. A mild decline in psycho-motor speed was seen in more than half of the patients, and motor slowing was related to higher radiation doses in midline and temporal lobe brain structures. Conclusion: Results suggest that in adults, tolerance for focused radiation is relatively high in cortical brain structures

  6. Pulsed dose rate and fractionated high dose rate brachytherapy: choice of brachytherapy schedules to replace low dose rate treatments

    International Nuclear Information System (INIS)

    Visser, Andries G.; Aardweg, Gerard J.M.J. van den; Levendag, Peter C.

    1996-01-01

    Purpose: Pulsed dose rate (PDR) brachytherapy is a new type of afterloading brachytherapy (BT) in which a continuous low dose rate (LDR) treatment is simulated by a series of 'pulses,' i.e., fractions of short duration (less than 0.5 h) with intervals between fractions of 1 to a few hours. At the Dr. Daniel den Hoed Cancer Center, the term 'PDR brachytherapy' is used for treatment schedules with a large number of fractions (at least four per day), while the term 'fractionated high dose rate (HDR) brachytherapy' is used for treatment schedules with just one or two brachytherapy fractions per day. Both treatments can be applied as alternatives for LDR BT. This article deals with the choice between PDR and fractionated HDR schedules and proposes possible fractionation schedules. Methods and Materials: To calculate HDR and PDR fractionation schedules with the intention of being equivalent to LDR BT, the linear-quadratic (LQ) model has been used in an incomplete repair formulation as given by Brenner and Hall, and by Thames. In contrast to earlier applications of this model, both the total physical dose and the overall time were not kept identical for LDR and HDR/PDR schedules. A range of possible PDR treatment schedules is presented, both for booster applications (in combination with external radiotherapy (ERT) and for BT applications as a single treatment. Because the knowledge of both α/β values and the half time for repair of sublethal damage (T (1(2)) ), which are required for these calculations, is quite limited, calculations regarding the equivalence of LDR and PDR treatments have been performed for a wide range of values of α/β and T (1(2)) . The results are presented graphically as PDR/LDR dose ratios and as ratios of the PDR/LDR tumor control probabilities. Results: If the condition that total physical dose and overall time of a PDR treatment must be exactly identical to the values for the corresponding LDR treatment regimen is not applied, there appears

  7. Improvements in dose calculation accuracy for small off-axis targets in high dose per fraction tomotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Hardcastle, Nicholas; Bayliss, Adam; Wong, Jeannie Hsiu Ding; Rosenfeld, Anatoly B.; Tome, Wolfgang A. [Department of Human Oncology, University of Wisconsin-Madison, WI, 53792 (United States); Department of Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, VIC 3002 (Australia) and Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522 (Australia); Department of Human Oncology, University of Wisconsin-Madison, WI 53792 (United States); Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522 (Australia) and Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur (Malaysia); Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522 (Australia); Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin 53792 (United States); Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53792 (United States); Einstein Institute of Oncophysics, Albert Einstein College of Medicine of Yeshiva University, Bronx, New York 10461 (United States) and Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522 (Australia)

    2012-08-15

    Purpose: A recent field safety notice from TomoTherapy detailed the underdosing of small, off-axis targets when receiving high doses per fraction. This is due to angular undersampling in the dose calculation gantry angles. This study evaluates a correction method to reduce the underdosing, to be implemented in the current version (v4.1) of the TomoTherapy treatment planning software. Methods: The correction method, termed 'Super Sampling' involved the tripling of the number of gantry angles from which the dose is calculated during optimization and dose calculation. Radiochromic film was used to measure the dose to small targets at various off-axis distances receiving a minimum of 21 Gy in one fraction. Measurements were also performed for single small targets at the center of the Lucy phantom, using radiochromic film and the dose magnifying glass (DMG). Results: Without super sampling, the peak dose deficit increased from 0% to 18% for a 10 mm target and 0% to 30% for a 5 mm target as off-axis target distances increased from 0 to 16.5 cm. When super sampling was turned on, the dose deficit trend was removed and all peak doses were within 5% of the planned dose. For measurements in the Lucy phantom at 9.7 cm off-axis, the positional and dose magnitude accuracy using super sampling was verified using radiochromic film and the DMG. Conclusions: A correction method implemented in the TomoTherapy treatment planning system which triples the angular sampling of the gantry angles used during optimization and dose calculation removes the underdosing for targets as small as 5 mm diameter, up to 16.5 cm off-axis receiving up to 21 Gy.

  8. Improvements in dose calculation accuracy for small off-axis targets in high dose per fraction tomotherapy

    International Nuclear Information System (INIS)

    Hardcastle, Nicholas; Bayliss, Adam; Wong, Jeannie Hsiu Ding; Rosenfeld, Anatoly B.; Tomé, Wolfgang A.

    2012-01-01

    Purpose: A recent field safety notice from TomoTherapy detailed the underdosing of small, off-axis targets when receiving high doses per fraction. This is due to angular undersampling in the dose calculation gantry angles. This study evaluates a correction method to reduce the underdosing, to be implemented in the current version (v4.1) of the TomoTherapy treatment planning software. Methods: The correction method, termed “Super Sampling” involved the tripling of the number of gantry angles from which the dose is calculated during optimization and dose calculation. Radiochromic film was used to measure the dose to small targets at various off-axis distances receiving a minimum of 21 Gy in one fraction. Measurements were also performed for single small targets at the center of the Lucy phantom, using radiochromic film and the dose magnifying glass (DMG). Results: Without super sampling, the peak dose deficit increased from 0% to 18% for a 10 mm target and 0% to 30% for a 5 mm target as off-axis target distances increased from 0 to 16.5 cm. When super sampling was turned on, the dose deficit trend was removed and all peak doses were within 5% of the planned dose. For measurements in the Lucy phantom at 9.7 cm off-axis, the positional and dose magnitude accuracy using super sampling was verified using radiochromic film and the DMG. Conclusions: A correction method implemented in the TomoTherapy treatment planning system which triples the angular sampling of the gantry angles used during optimization and dose calculation removes the underdosing for targets as small as 5 mm diameter, up to 16.5 cm off-axis receiving up to 21 Gy.

  9. Short-term irradiation of the glioblastoma with high-dosed fractions

    International Nuclear Information System (INIS)

    Hinkelbein, W.; Bruggmoser, G.; Schmidt, M.; Wannenmacher, M.

    1984-01-01

    Compared to surgery alone, postoperative radiotherapy leads with glioblastomas (grade IV gliomas) to a significant improvement of the therapeutic results. The prolongation of survival time, however, is to a large extent compensated by the therapy itself (it normally implicates hospitalisation). Therefore, we tested the efficiency of rapid course irradiation with high fractions. 70 patients were treated daily with individual fractions of 3.5 Gy, 4 to 6 fractions per week. The entire dose amounted to 31.5 to 38.5 Gy. The average survival time was 33.5 weeks corresponding to the survival time known from the combined surgical and radiotherapeutical treatment of glioblastomas. An effective increase in therapy-free survival time seems possible, especially when the entire focal dose does not exceed 35 Gy. It is remarkable that the patients with the maximum exposure did not have the longest survival times and rates. Living conditions for the patients were similar to those with conventional fractioning, or even better. Rapid course irradiation with high fractions and a limited total dose (35 Gy) presently is - apart from the accelerated superfractioning - a successful measure to prolong the therapyfree survival time for patients with grade IV gliomas. (orig.) [de

  10. What minimum number of fractions is required with high dose-rate remote afterloading; and reply

    International Nuclear Information System (INIS)

    Orton, C.G.

    1987-01-01

    The author presents 'a more rigorous application of the linear quadratic model for protracted radiotherapy than Dale (1985)' and demonstrates that considerably fewer than 17 fractions are needed, a conclusion particularly relevant to treatment of cancer of the cervix. Dale's reply is based on the tenet that Orton has misquoted the use of the damage repair constants. (UK)

  11. Perioperative fractionated high-dose rate brachytherapy for malignant bone and soft tissue tumors

    International Nuclear Information System (INIS)

    Koizumi, Masahiko; Inoue, Takehiro; Yamazaki, Hideya; Teshima, Teruki; Tanaka, Eiichi; Yoshida, Ken; Imai, Atsushi; Shiomi, Hiroya; Kagawa, Kazufumi; Araki, Nobuto; Kuratsu, Shigeyuki; Uchida, Atsumasa; Inoue, Toshihiko

    1999-01-01

    Purpose: To investigate the viability of perioperative fractionated HDR brachytherapy for malignant bone and soft tissue tumors, analyzing the influence of surgical margin. Methods and Materials: From July 1992 through May 1996, 16 lesions of 14 patients with malignant bone and soft tissue tumors (3 liposarcomas, 3 MFHs, 2 malignant schwannomas, 2 chordomas, 1 osteosarcoma, 1 leiomyosarcoma, 1 epithelioid sarcoma, and 1 synovial sarcoma) were treated at the Osaka University Hospital. The patients' ages ranged from 14 to 72 years (median: 39 years). Treatment sites were the pelvis in 6 lesions, the upper limbs in 5, the neck in 4, and a lower limb in 1. The resection margins were classified as intracapsular in 5 lesions, marginal in 5, and wide in 6. Postoperative fractionated HDR brachytherapy was started on the 4th-13th day after surgery (median: 6th day). The total dose was 40-50 Gy/7-10 fr/ 4-7 day (bid) at 5 or 10 mm from the source. Follow-up periods were between 19 and 46 months (median: 30 months). Results: Local control rates were 75% at 1 year and 48% in 2 years, and ultimate local control was achieved in 8 (50%) of 16 lesions. Of the 8 uncontrolled lesions, 5 (63%) had intracapsular (macroscopically positive) resection margins, and all the 8 controlled lesions (100%) had marginal (microscopically positive) or wide (negative) margins. Of the total, 3 patients died of both tumor and metastasis, 3 of metastasis alone, 1 of tumor alone, and 7 showed no evidence of disease. Peripheral nerve palsy was seen in one case after this procedure, but no infection or delayed wound healing caused by tubing or irradiation has occurred. Conclusion: Perioperative fractionated HDR brachytherapy is safe, well tolerated, and applicable to marginal or wide surgical margin cases

  12. Comparison of patient-reported acute urinary and sexual toxicity scores in a 6- versus 2-fraction course of high-dose-rate prostate brachytherapy monotherapy

    International Nuclear Information System (INIS)

    Ragab, Omar; Park, Sang-June; Zhang, Mingle; Wang, Jason; Velez, Maria; Demanes, David J.; Banerjee, Robyn; Patel, Shyamal; Kamrave, Mitchell

    2018-01-01

    To identify differences in acute urinary and sexual toxicity between a 6-fraction and 2-fraction high-dose-rate brachytherapy monotherapy regimen and correlate dosimetric constraints to short-term toxicity. A single institution retrospective study of 116 men with prostate cancer treated with HDR monotherapy from 2010 to 2015 was conducted. Eighty-one men had 7.25 Gy × 6-fractions and 35 men had 13.5 Gy × 2-fractions. Patients had two CT-planned implants spaced 1–2 weeks apart. Patient baseline characteristics, International Prostate Symptom Scores (IPSS) and Sexual Health Inventory for Men (SHIM) scores were collected pre-treatment and 3, 6 and 12 months post-implantation. Mixed effect modelling was undertaken to compare baseline, 1–6 month and 7–12 month scores between groups. Poisson regression analysis was performed to correlate dosimetric constraints with acute toxicity. There was no difference between baseline and post-implantation IPSS scores between 6-fraction and 2-fraction groups. SHIM scores for men treated with 6-fractions had a steeper decline at 1–6 months, but resolved at 7–12 months. Pre-treatment alpha-blocker use correlated with worse short-term acute urinary toxicity. Worsened SHIM score correlated with increasing age, diabetes mellitus and androgen-deprivation therapy. In a dosimetric analysis of outcomes, prostate V150 dose and bladder wall (D01.cc, D1cc, D2cc) dose correlated with increased IPSS score. No increased acute genitourinary or sexual dysfunction has been observed in men when transitioning from 6-fraction to 2-fraction HDR monotherapy. A dosimetric correlation was found between the V150 and bladder wall doses for acute urinary toxicity. Future research should continue to standardize and validate dose constraints for prostate HDR monotherapy patients.

  13. The optimal fraction size in high-dose-rate brachytherapy: dependency on tissue repair kinetics and low-dose rate

    International Nuclear Information System (INIS)

    Sminia, Peter; Schneider, Christoph J.; Fowler, Jack F.

    2002-01-01

    Background and Purpose: Indications of the existence of long repair half-times on the order of 2-4 h for late-responding human normal tissues have been obtained from continuous hyperfractionated accelerated radiotherapy (CHART). Recently, these data were used to explain, on the basis of the biologically effective dose (BED), the potential superiority of fractionated high-dose rate (HDR) with large fraction sizes of 5-7 Gy over continuous low-dose rate (LDR) irradiation at 0.5 Gy/h in cervical carcinoma. We investigated the optimal fraction size in HDR brachytherapy and its dependency on treatment choices (overall treatment time, number of HDR fractions, and time interval between fractions) and treatment conditions (reference low-dose rate, tissue repair characteristics). Methods and Materials: Radiobiologic model calculations were performed using the linear-quadratic model for incomplete mono-exponential repair. An irradiation dose of 20 Gy was assumed to be applied either with HDR in 2-12 fractions or continuously with LDR for a range of dose rates. HDR and LDR treatment regimens were compared on the basis of the BED and BED ratio of normal tissue and tumor, assuming repair half-times between 1 h and 4 h. Results: With the assumption that the repair half-time of normal tissue was three times longer than that of the tumor, hypofractionation in HDR relative to LDR could result in relative normal tissue sparing if the optimum fraction size is selected. By dose reduction while keeping the tumor BED constant, absolute normal tissue sparing might therefore be achieved. This optimum HDR fraction size was found to be largely dependent on the LDR dose rate. On the basis of the BED NT/TUM ratio of HDR over LDR, 3 x 6.7 Gy would be the optimal HDR fractionation scheme for replacement of an LDR scheme of 20 Gy in 10-30 h (dose rate 2-0.67 Gy/h), while at a lower dose rate of 0.5 Gy/h, four fractions of 5 Gy would be preferential, still assuming large differences between tumor

  14. Effects of a single high dose of 55Fe in mice

    International Nuclear Information System (INIS)

    Laissue, J.A.; Burlington, H.; Cronkite, E.P.; Heldman, B.; Reincke, U.

    1979-01-01

    High doses of 55 Fe induced cytocide in maturing erythroid cells, due to the short-range deposition of decay energy. Organ damage at the time of death was evaluated in a group of 45 female mice of the C 57 BL/6 J strain given a single i.v. injection of 2,800 μCi, 1,400 μCi or 700 μCi of 55 FeCl 3 when 10 to 14 weeks old. A corresponding amount of cold iron was given to control animals by the same route. Radioiron-treated mice died spontaneously, or were killed when moribund. Mice given 2,800 μCi died after a median survival time of 27 days with severe depletion of hemopoietic cells in bone marrow and spleen, marked atrophy of lymphoid tissues and mild liver damage. After 1,400 μCi or 700 μCi, the median survival time was 117 and 439, respectively. In contrast, median survival was 847 days in control animals allowed to survive. In the two lower 55 Fe-dose groups, there was a dose-dependent pancytopenia. Atrophy of lymphoid tissues was moderate, and signs of liver damage slight. The degree of organ hemosiderosis in experimental and control animals was slight to moderate. Organ damage associated with deposition of cold iron was not apparent in tissue sections. Morphological signs of damage to non-hemopoietic organs such as the liver were not conspicuous. Direct radiation damage, primarily to the erythroid series, and competition for stem cells between the heavily depleted erythroid and the other hemopoietic cell lines must be considered among the possible factors leading to pancytopenia. Out of 14 55 Fe-treated mice who survived longer than 300 days developed tumors of hemopoietic and lymphoid tissues, or osteosarcomas. (orig./MG) [de

  15. Interstitial high-dose-rate brachytherapy boost: The feasibility and cosmetic outcome of a fractionated outpatient delivery scheme

    International Nuclear Information System (INIS)

    Manning, Matthew A.; Arthur, Douglas W.; Schmidt-Ullrich, Rupert K.; Arnfield, Mark R.; Amir, Cyrus; Zwicker, Robert D.

    2000-01-01

    Purpose: To evaluate the feasibility, potential toxicity, and cosmetic outcome of fractionated interstitial high dose rate (HDR) brachytherapy boost for the management of patients with breast cancer at increased risk for local recurrence. Methods and Materials: From 1994 to 1996, 18 women with early stage breast cancer underwent conventionally fractionated whole breast radiotherapy (50-50.4 Gy) followed by interstitial HDR brachytherapy boost. All were considered to be at high risk for local failure. Seventeen had pathologically confirmed final surgical margins of less than 2 mm or focally positive. Brachytherapy catheter placement and treatment delivery were conducted on an outpatient basis. Preplanning was used to determine optimal catheter positions to enhance dose homogeneity of dose delivery. The total HDR boost dose was 15 Gy delivered in 6 fractions of 2.5 Gy over 3 days. Local control, survival, late toxicities (LENT-SOMA), and cosmetic outcome were recorded in follow-up. In addition, factors potentially influencing cosmesis were analyzed by logistic regression analysis. Results: The minimum follow-up is 40 months with a median 50 months. Sixteen patients were alive without disease at last follow-up. There have been no in-breast failures observed. One patient died with brain metastases, and another died of unrelated causes without evidence of disease. Grade 1-2 late toxicities included 39% with hyperpigmentation, 56% with detectable fibrosis, 28% with occasional discomfort, and 11% with visible telangiectasias. Grade 3 toxicity was reported in one patient as persistent discomfort. Sixty-seven percent of patients were considered to have experienced good/excellent cosmetic outcomes. Factors with a direct relationship to adverse cosmetic outcome were extent of surgical defect (p = 0.00001), primary excision volume (p = 0.017), and total excision volume (p = 0.015). Conclusions: For high risk patients who may benefit from increased doses, interstitial HDR

  16. In vivo dosimetry of high-dose fractionated irradiation in an experimental set-up with rats

    Energy Technology Data Exchange (ETDEWEB)

    Fortan, L; Van Hecke, H; Van Duyse, B; De Neve, W; De Meerleer, B [Ghent Rijksuniversiteit (Belgium). Kliniek voor Radiotherapie en Kerngeneeskunde; Pattyn, P; Van Renthergem, K [Ghent University (Belgium). Dept. of Surgery

    1995-12-01

    The feasibility to irradiate a limited section of a rat abdomen with well-defined edges was assessed. Because of the relative small volume involved, in vivo dosimetry with TLDs was necessary in providing us information about the accuracy of the irradiation method. Three to five days prior to the start of the radiotherapy treatment, two plastic strips - each containing a TLD-dosimeter (Harshaw TLD10 LiF rods, 1 mm dia x 6 mm) sealed in polyethylene tubing, and a lead bean - were implanted in the rat abdomen. The plastic strips made a closed loop around the bowel, through the mesenterium, and were fixed with a single stitch on the inner abdominal wall. One loop was made in the hepatic area; another was made in the lower abdomen, around the rectosigmoid. Conscious animals were irradiated using a purpose-build plexi-holder, with rear legs immobilised to avoid longitudinal movements. The implanted lead beans enabled us to simulate the rat prior to each radiation session. This way, the radiation field could be set up individually for each rat, in such way that the rectosigmoid area received full dose and the hepatic area received no irradiation dose at all. Irradiation was carried out, using 5 MV photons of a linear accelerator. Fifteen animals per group were irradiated according a conventional (2.0 Gy / fraction; 5 fractions / week) or a hyperfractionated (1.6 Gy / fraction; 2 daily fractions; 5 days / week) schedule, with different total doses. Prior to implantation, TLDs were individually calibrated and checked for stability. After removal from the abdomen . TLDs were tested again for accuracy. TLDs with an unacceptable read-out curve were rejected (about 2 to 4 TLDs per group of 15). The obtained accumulated doses - as determined by TLD read-outs-were comparable to the theoretical doses, indicating that fractionated radiation of small fields, with well defined mark off, in rats is feasible.

  17. In vivo dosimetry of high-dose fractionated irradiation in an experimental set-up with rats

    International Nuclear Information System (INIS)

    Fortan, L.; Van Hecke, H.; Van Duyse, B.; De Neve, W.; De Meerleer, B.; Pattyn, P.; Van Renthergem, K.

    1995-01-01

    The feasibility to irradiate a limited section of a rat abdomen with well-defined edges was assessed. Because of the relative small volume involved, in vivo dosimetry with TLDs was necessary in providing us information about the accuracy of the irradiation method. Three to five days prior to the start of the radiotherapy treatment, two plastic strips - each containing a TLD-dosimeter (Harshaw TLD10 LiF rods, 1 mm dia x 6 mm) sealed in polyethylene tubing, and a lead bean - were implanted in the rat abdomen. The plastic strips made a closed loop around the bowel, through the mesenterium, and were fixed with a single stitch on the inner abdominal wall. One loop was made in the hepatic area; another was made in the lower abdomen, around the rectosigmoid. Conscious animals were irradiated using a purpose-build plexi-holder, with rear legs immobilised to avoid longitudinal movements. The implanted lead beans enabled us to simulate the rat prior to each radiation session. This way, the radiation field could be set up individually for each rat, in such way that the rectosigmoid area received full dose and the hepatic area received no irradiation dose at all. Irradiation was carried out, using 5 MV photons of a linear accelerator. Fifteen animals per group were irradiated according a conventional (2.0 Gy / fraction; 5 fractions / week) or a hyperfractionated (1.6 Gy / fraction; 2 daily fractions; 5 days / week) schedule, with different total doses. Prior to implantation, TLDs were individually calibrated and checked for stability. After removal from the abdomen . TLDs were tested again for accuracy. TLDs with an unacceptable read-out curve were rejected (about 2 to 4 TLDs per group of 15). The obtained accumulated doses - as determined by TLD read-outs-were comparable to the theoretical doses, indicating that fractionated radiation of small fields, with well defined mark off, in rats is feasible

  18. 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.

  19. High Dose Rate Brachytherapy in Two 9 Gy Fractions in the Treatment of Locally Advanced Cervical Cancer - a South Indian Institutional Experience.

    Science.gov (United States)

    Ghosh, Saptarshi; Rao, Pamidimukkala Bramhananda; Kotne, Sivasankar

    2015-01-01

    Although 3D image based brachytherapy is currently the standard of treatment in cervical cancer, most of the centres in developing countries still practice orthogonal intracavitary brachytherapy due to financial constraints. The quest for optimum dose and fractionation schedule in high dose rate (HDR) intracavitary brachytherapy (ICBT) is still ongoing. While the American Brachytherapy Society recommends four to eight fractions of each less than 7.5 Gy, there are some studies demonstrating similar efficacy and comparable toxicity with higher doses per fraction. To assess the treatment efficacy and late complications of HDR ICBT with 9 Gy per fraction in two fractions. This is a prospective institutional study in Southern India carried on from 1st June 2012 to 31st July 2014. In this period, 76 patients of cervical cancer satisfying our inclusion criteria were treated with concurrent chemo-radiation following ICBT with 9 Gy per fraction in two fractions, five to seven days apart. The median follow-up period in the study was 24 months (range 10.6 - 31.2 months). The 2 year actuarial local control rate, disease-free survival and overall survival were 88.1%, 84.2% and 81.8% respectively. Although 38.2% patients suffered from late toxicity, only 3 patients had grade III late toxicity. In our experience, HDR brachytherapy with 9 Gy per fraction in two fractions is an effective dose fractionation for the treatment of cervical cancer with acceptable toxicity.

  20. Correlation between the single, high dose of ingested baclofen and clinical symptoms

    Directory of Open Access Journals (Sweden)

    Jacek Sein Anand

    2017-12-01

    There is a statistically significant correlation between the dose of ingested baclofen and the presence of acute respiratory failure, and duration of mechanical ventilation. Patients who have taken a single dose of baclofen of 200 mg, or higher, should be managed in centres able to provide continuous monitoring of life functions. Those with a higher level of a single dose of baclofen ingestion (>500 mg, should be hospitalized in a Toxicology Unit or Intensive Care Unit able to provide airway support and mechanical ventilation.

  1. Single-shot, high-dose rabbit ATG for rejection prophylaxis after kidney transplantation

    NARCIS (Netherlands)

    R. Zietse (Bob); E.P.M. van Steenberge (E. P M); C.J. Hesse (Cees); L.B. Vaessen (L.); J.N.M. IJzermans (Jan); W. Weimar (Willem)

    1993-01-01

    textabstractWe studied the effects of a single intravenous injection of rabbit ATG (RIVM, Bilthoven, The Netherlands) in a dose of 8 mg/kg body weight administered 6 h after kidney transplantation on graft survival, rejection incidence, T-cell subsets, and cost-effectiveness. A total of 58 (37

  2. High-dose-rate brachytherapy as monotherapy delivered in two fractions within one day for favorable/intermediate-risk prostate cancer: preliminary toxicity data.

    Science.gov (United States)

    Ghilezan, Michel; 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

    2012-07-01

    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 × 2) for a total dose of 24 Gy, delivered within 1 day. The dose was subsequently increased to 27 Gy (13.5 Gy × 2) delivered in 1 day. We report the acute and early chronic genitourinary and gastrointestinal toxicity. 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. 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. Favorable-risk prostate cancer patients treated with a single implant HDR-BT to 24-27 Gy in two fractions

  3. 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

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

    International Nuclear Information System (INIS)

    Ghilezan, Michel; 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

    2012-01-01

    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 × 2) for a total dose of 24 Gy, delivered within 1 day. The dose was subsequently increased to 27 Gy (13.5 Gy × 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-risk prostate cancer patients treated with

  5. Single high dose intraoperative electrons for advanced stage pancreatic cancer: Phase I pilot study

    International Nuclear Information System (INIS)

    Goldson, A.L.; Ashaveri, E.; Espinoza, M.C.

    1981-01-01

    Phase I toxicity studies with intraoperative radiotherapy proved to be a feasible adjunct to surgery for unresectable malignancies of the pancreas at Howard University Hospital. There have been minimal side effects or complications related to the combination of limited surgical decompression and intraoperative radiotherapy alone. The toxic effects of intraoperative radiotherapy on normal tissues is being assessed on a dose volume basis. Doses of 2000 to 2500 rad in a single exposure to include the pancreas, regional nodes and duodenum are acceptable if the total treatment volume is less than or equal to 100 cm. The tumoricidal effects on the cancer are demonstratable when one reviews the pathological specimens that illustrate massive tumor necrosis and fibros replacement, but in all cases reviewed, viable cancer was noted. Intraoperative radiotherapy, therefore, represents a significant boost dose for resectable, partially resectable or non-resectable tumors when added to conventional external beam irradiation and/or chemotherapy. Preliminary clinical data and minimal toxicity justifies further investigation

  6. Computed tomography-guided interstitial high dose rate brachytherapy for centrally located liver tumours: a single institution study

    Energy Technology Data Exchange (ETDEWEB)

    Tselis, Nikolaos; Chatzikonstantinou, Georgios; Zamboglou, Nikolaos [Klinikum Offenbach, Department of Radiation Oncology, Offenbach am Main (Germany); Kolotas, Christos [Hirslanden Medical Center, Institute for Radiotherapy, Aarau (Switzerland); Milickovic, Natasa; Baltas, Dimos [Klinikum Offenbach, Department of Medical Physics and Engineering, Offenbach am Main (Germany)

    2013-08-15

    To evaluate the clinical outcome of computed tomography (CT)-guided interstitial (IRT) high-dose-rate (HDR) brachytherapy (BRT) in the treatment of unresectable primary and secondary liver malignancies. This report updates and expands our previously described experience with this treatment technique. Forty-one patients with 50 tumours adjacent to the liver hilum and bile duct bifurcation were treated in 59 interventions of CT-guided IRT HDR BRT. The tumours were larger than 4 cm with a median volume of 84 cm{sup 3} (38-1,348 cm{sup 3}). The IRT HDR BRT delivered a median total physical dose of 20.0 Gy (7.0-32.0 Gy) in twice daily fractions of median 7.0 Gy (4.0-10.0 Gy) in 19 patients and in once daily fractions of median 8.0 Gy (7.0-14.0 Gy) in 22 patients. With a median follow-up of 12.4 months, the local control for metastatic hepatic tumours was 89 %, 73 % and 63 % at 6, 12 and 18 months respectively. The local control for primary hepatic tumours was 90 %, 81 % and 50 % at 6, 12 and 18 months respectively. Severe side effects occurred in 5.0 % of interventions with no treatment-related deaths. CT-guided IRT HDR BRT is a promising procedure for the radiation treatment of centrally located liver malignancies. (orig.)

  7. A comparison of anti-tumor effects of high dose rate fractionated and low dose rate continuous irradiation in multicellular spheroids

    International Nuclear Information System (INIS)

    Kubota, Nobuo; Omura, Motoko; Matsubara, Sho.

    1997-01-01

    In a clinical experience, high dose rate (HDR) fractionated interstitial radiotherapy can be an alternative to traditional low dose rate (LDR) continuous interstitial radiotherapy for head and neck cancers. To investigate biological effect of HDR, compared to LDR, comparisons have been made using spheroids of human squamous carcinoma cells. Both LDR and HDR were delivered by 137 Cs at 37degC. Dose rate of LDR was 8 Gy/day and HDR irradiations of fraction size of 4, 5 or 6 Gy were applied twice a day with an interval time of more than 6 hr. We estimated HDR fractionated dose of 31 Gy with 4 Gy/fr to give the same biological effects of 38 Gy by continuous LDR for spheroids. The ratio of HDR/LDR doses to control 50% spheroids was 0.82. (author)

  8. High-dose-rate brachytherapy with two or three fractions as monotherapy in the treatment of locally advanced prostate cancer

    International Nuclear Information System (INIS)

    Hoskin, Peter; Rojas, Ana; Ostler, Peter; Hughes, Robert; Alonzi, Roberto; Lowe, Gerry; Bryant, Linda

    2014-01-01

    Background: To evaluate late urinary (GU) and gastrointestinal (GI) adverse events (AEs) and biochemical control of disease after high-dose rate brachytherapy (HDR-BT) in locally advanced prostate cancer. Patients and methods: 227 consecutive patients were treated with 3 × 10.5 Gy (n = 109) or 2 × 13 Gy (n = 118) HDR-BT alone. Biochemical failure was assessed using the Phoenix definition of PSA nadir + 2 μg/l and late AEs using the RTOG scoring system and the International Prostate Symptom Score (IPSS). Results: Kaplan–Meier estimates and prevalence of late events indicate that urinary, bowel and IPSS symptoms are higher after 31.5 Gy than after 26 Gy, however differences are significant only for Grade 1 and 2 urinary toxicity. Kaplan–Meier estimates of morbidity are consistently and considerably higher than time-point estimates of prevalence; which reflects the transient nature of most symptoms. At 3 years 93% and 97% of patients treated with 26 and 31.5 Gy, respectively, were free from biochemical relapse (p = 0.5) and 91% for the latter regimen at 5 years. In univariate and multivariate analysis risk-category was the only significant predictor of relapse (p < 0.03). Conclusion: These HDR-BT schedules achieved high levels of biochemical control of disease in patients with advanced prostate cancer with few severe complications seen throughout the first 3 years

  9. Inter fraction variations in rectum and bladder volumes and dose distributions during high dose rate brachytherapy treatment of the uterine cervix investigated by repetitive CT-examinations

    International Nuclear Information System (INIS)

    Hellebust, Taran Paulsen; Dale, Einar; Skjoensberg, Ane; Olsen, Dag Rune

    2001-01-01

    Purpose: To evaluate variation of dose to organs at risk for patients receiving fractionated high dose rate gynaecological brachytherapy by using CT-based 3D treatment planning and dose-volume histograms (DVH). Materials and methods: Fourteen patients with cancer of the uterine cervix underwent three to six CT examinations (mean 4.9) during their course of high-dose-rate brachytherapy using radiographically compatible applicators. The rectal and bladder walls were delineated and DVHs were calculated. Results: Inter fraction variation of the bladder volume (CV mean =44.1%) was significantly larger than the inter fraction variation of the mean dose (CV mean =19.9%, P=0.005) and the maximum dose (CV mean =17.5%, P=0.003) of the bladder wall. The same trend was seen for rectum, although the figures were not significantly different. Performing CT examinations at four of seven brachytherapy fractions reduced the uncertainty to 4 and 7% for the bladder and rectal doses, respectively. A linear regression analysis showed a significant, negative relationship between time after treatment start and the whole bladder volume (P=0.018), whereas no correlation was found for the rectum. For both rectum and bladder a linear regression analysis revealed a significant, negative relationship between the whole volume and median dose (P<0.05). Conclusion: Preferably a CT examination should be provided at every fraction. However, this is logistically unfeasible in most institutions. To obtain reliable DVHs the patients will in the future undergo 3-4 CT examinations during the course of brachytherapy at our institution. Since this study showed an association between large bladder volumes and dose reductions, the patients will be treated with a standardized bladder volume

  10. Improved long-term survival after intra-operative single high-dose ATG-Fresenius induction in renal transplantation: a single centre experience.

    Science.gov (United States)

    Kaden, Jürgen; May, Gottfried; Völp, Andreas; Wesslau, Claus

    2009-01-01

    In organ grafts donor-specific sensitization is initiated immediately after revascularization. Therefore, in 1990 we introduced the intra-operative single high-dose ATG-Fresenius (ATG-F) induction in addition to standard triple drug therapy (TDT) consisting of steroids, azathioprine and cyclosporin. A total of 778 first renal transplantations from deceased donors, performed between 1987 and 1998, were included in this evaluation. This retrospective analysis of clinic records and electronic databases presents data of all recipients of first kidney grafts who received two different ATG-F inductions (1(st) group: 9 mg/kg body weight as single high-dose intra-operatively, n=484; 2(nd) group: 3 mg/kg body weight on 7 or 8 consecutive days as multiple-dose starting also intra-operatively, n=78) and standard TDT alone (3(rd) group: TDT alone, n=216). The 10-year patient survival rates were 72.6+/-2.6% (TDT + ATG-F single high-dose), 79.5+/-5.1% (TDT + ATG-F multiple-dose) and 67.2+/-3.7%% (TDT alone; Kaplan-Meier estimates with standard errors; ATG-F vs TDT alone, p=0.001). The 10-year graft survival rates with censoring of patients that died with a functioning graft were 73.8+/-2.4%, 57.7+/-5.8% and 58.4+/-3.6% (Kaplan-Meier estimates with standard errors; 1(st) vs 2(nd )and 3(rd) group, respectively, p<0.001) and the 10-year graft survival rates with patient death counted as graft failure were 58.3+/-2.7%, 55.7+/-5.8% and 48.2+/-3.5% (Kaplan-Meier estimates with standard errors; ATG-F single high-dose vs TDT, p=0.023). In pre-sensitized recipients there were also significant differences in favour of ATG-F, more notably in the single high-dose ATG-F induction. A total of 69% of the patients in the two cohorts receiving ATG-F did not experience any transplant rejections compared to 56% in patients undergoing TDT alone (p=0.018). The incidence of infectious complications was comparable across all groups. According to evidence obtained from the routine documentation of 778

  11. Efficacy and Safety of Single and Double Doses of Ivermectin versus 7-Day High Dose Albendazole for Chronic Strongyloidiasis

    Science.gov (United States)

    Suputtamongkol, Yupin; Premasathian, Nalinee; Bhumimuang, Kid; Waywa, Duangdao; Nilganuwong, Surasak; Karuphong, Ekkapun; Anekthananon, Thanomsak; Wanachiwanawin, Darawan; Silpasakorn, Saowaluk

    2011-01-01

    , and double doses of oral ivermectin respectively (P = 0.006) in modified intention to treat analysis. No serious adverse event associated with treatment was found in any of the groups. Conclusion/Significance This study confirms that both a single, and a double dose of oral ivermectin taken two weeks apart, is more effective than a 7-day course of high dose albendazole for patients with chronic infection due to S. stercoralis. Double dose of ivermectin, taken two weeks apart, might be more effective than a single dose in patients with concomitant illness. Trial Registration ClinicalTrials.gov NCT00765024 PMID:21572981

  12. Perioperative single high dose ATG-Fresenius S administration as induction immunosuppressive therapy in cadaveric renal transplantation--preliminary results.

    Science.gov (United States)

    Samsel, R; Chmura, A; Włodarczyk, Z; Wyzgał, J; Cieciura, T; Lagiewska, B; Pliszczyński, J; Korczak, G; Lazowski, T; Paczek, L; Wałaszewski, J; Lao, M; Rowiński, W

    1999-01-01

    Monoclonal and polyclonal antilymphocyte antibodies have been used successfully in organ transplantation as induction therapy and in the treatment of acute graft rejection. Used for induction the medication is generally given for the first 7-10 days. The aim of this study was to assess the safety and efficacy of single high dose (9 mg/kg) ATG Fresenius S given perioperatively, before revascularization, to kidney allograft recipients. During last twelve months seventy six, first cadaveric kidney adult recipients were included into the study in two centers (center A-64, center B-12). All patients received triple drug immunosuppression (Neoral, steroids and Cellcept which was replaced by azathioprine after 4 months), and were randomized to receive ATG or not. The follow-up period ranged from 1 month up to 1 year. The preliminary results are very promising, the rejection rate in bolus group was significantly lower than in control. No significant side effects or serious adverse events in both groups were observed.

  13. Evaluation of Geometrically Optimized Single- and Double-plane Interstitial High Dose Rate Implants with Respect to Conformality and Homogeneity

    International Nuclear Information System (INIS)

    Major, Tibor; Polgar, Csaba; Fodor, Janos; Takacsi-nagy, Zoltan; Mangel, Laszlo; Nemeth, Gyoergy

    2003-01-01

    The use of a stepping source in high dose rate brachytherapy supported with dwell-time optimization makes it possible to deviate from the classical dosimetry systems. Dose distributions of single- and double-plane implants were analysed for conformality and homogeneity at idealized target volumes. The Paris system was used for catheter positioning and target volume determination. Geometric optimization and individual dose prescription were applied. Volumetric indices and dose parameters were calculated at optimal active length, which was found to be equal to target volume length. The mean conformality, homogeneity, external volume and overdose volume indices were 0.78, 0.67, 0.22 and 0.13, respectively. The average minimum target and reference doses were 69% and 86%, respectively. Comparisons between the volumetric indices of geometrical optimized and non-optimized implants were also performed, and a significant difference was found regarding any index. The geometrical optimization resulted in superior conformality and slightly inferior homogeneity. At geometrically optimized implants, the active length can be reduced compared to non-optimized implants. Volumetric parameters and dose-volume histogram-based individual dose prescription are recommended for quantitative assessment of interstitial implants

  14. High-Dose Spatially Fractionated GRID Radiation Therapy (SFGRT): A Comparison of Treatment Outcomes With Cerrobend vs. MLC SFGRT

    International Nuclear Information System (INIS)

    Neuner, Geoffrey; Mohiuddin, Majid M.; Vander Walde, Noam; Goloubeva, Olga; Ha, Jonathan; Yu, Cedric X.; Regine, William F.

    2012-01-01

    Purpose: Spatially fractionated GRID radiotherapy (SFGRT) using a customized Cerrobend block has been used to improve response rates in patients with bulky tumors. The clinical efficacy of our own multileaf collimator (MLC) technique is unknown. We undertook a retrospective analysis to compare clinical response rates attained using these two techniques. Methods and Materials: Seventy-nine patients with bulky tumors (median diameter, 7.6 cm; range, 4–30 cm) treated with SFGRT were reviewed. Between 2003 and late 2005, the Cerrobend block technique (n = 39) was used. Between late 2005 and 2008, SFGRT was delivered using MLC-shaped fields (n = 40). Dose was prescribed to dmax (depth of maximum dose) and was typically 15 Gy. Eighty percent of patients in both groups received external beam radiotherapy in addition to SFGRT. The two-sided Fisher-Freeman-Halton test was used to compare pain and mass effect response rates between the two groups. Results: Sixty-one patients (77%) were treated for palliative intent and 18 (23%) for curative intent. The majority of patients had either lung or head-and-neck primaries in both groups; the most frequent site of SFGRT application was the neck. The majority of patients complained of either pain (65%) or mass effect (58%) at intake. Overall response rates for pain and mass response were no different between the Cerrobend and MLC groups: pain, 75% and 74%, respectively (p = 0.50), and mass effect, 67% and 73%, respectively (p = 0.85). The majority of toxicities were Grade 1 or 2, and only 3 patients had late Grade 3-4 toxicities. Conclusions: MLC-based and Cerrobend-based SFGRT have comparable and encouraging response rates when used either in the palliative or curative setting. MLC-based SGFRT should allow clinics to more easily adopt this novel treatment approach for the treatment of bulky tumors.

  15. Skull base chordomas: treatment outcome and prognostic factors in adult patients following conformal treatment with 3D planning and high dose fractionated combined proton and photon radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Munzenrider, J E; Hug, E; McManus, P; Adams, J; Efird, J; Liebsch, N J

    1995-07-01

    Purpose: To report treatment outcome and prognostic factors for local recurrence-free survival and overall survival in adult patients with skull base chordomas treated with 3D planning and high dose fractionated combined proton and photon radiation therapy. Methods and Materials: From 1975 through 1993, 132 adult patients with skull base chordomas were treated with fractionated combined proton and photon radiation therapy. Seventy five patients (57%) were male and 57 (43%) female. Age ranged from 19 to 80 years (median 45.5 years). All pathology was verified at MGH by a single pathologist. Ninety six had non-chondroid (NCC) and 36 chondroid chordomas (CC), respectively. Median prescribed dose was 68.7 CGE (CGE, Cobalt Gray-equivalent: proton Gy X RBE 1.1 + photon Gy), ranging from 36 to 79.2 CGE; 95% received {>=} 66.6 CGE. Between 70 and 100% of the dose was given with the 160 MeV proton beam at the Harvard Cyclotron. 3D CT-based treatment planning has been employed in all patients treated since 1980. Median follow-up was 46 months (range 2-158 months). Results: Treatment outcome was evaluated in terms of local recurrence-free survival (LRFS) and disease specific survival (DSS), as well as treatment-related morbidity. Local failure (LF), defined as progressive neurological deficit with definite increase in tumor volume on CT or MRI scan, occurred in 39 patients (29.5%). LF was more common among women than among men:(26(57)) (46%) vs (13(75)) (17%), respectively. Thirty three of the 39 LF were seen in non-chondroid chordoma patients, with 6 occurring in patients with the chondroid variant (34% of NCC and 17% of CC), respectively. Distant metastasis was documented in 8 patients. LRFS was 81 {+-} 5.8%, 59 {+-} 8.3%, and 43 {+-} 10.4%, and DSS was 94 {+-} 3.6%, 80 {+-} 6.7%, and 50 {+-} 10.7% at 36, 60, and 96 months, respectively, for the total group. LRFS and DSS were not significantly different for patients with NCC than those with CC (p > .05). Gender was

  16. Ionizing radiation and autoimmunity: Induction of autoimmune disease in mice by high dose fractionated total lymphoid irradiation and its prevention by inoculating normal T cells

    International Nuclear Information System (INIS)

    Sakaguchi, N.; Sakaguchi, S.; Miyai, K.

    1992-01-01

    Ionizing radiation can functionally alter the immune system and break self-tolerance. High dose (42.5 Gy), fractionated (2.5 Gy 17 times) total lymphoid irradiation (TLI) on mice caused various organ-specific autoimmune diseases, such as gastritis, thyroiditis, and orchitis, depending on the radiation dosages, the extent of lymphoid irradiation, and the genetic background of the mouse strains. Radiation-induced tissue damage is not the primary cause of the autoimmune disease because irradiation of the target organs alone failed to elicit the autoimmunity and shielding of the organs from irradiation was unable to prevent it. In contrast, irradiation of both the thymus and the peripheral lymphoid organs/tissues was required for efficient induction of autoimmune disease by TLI. TLI eliminated the majority of mature thymocytes and the peripheral T cells for 1 mo, and inoculation of spleen cell, thymocyte, or bone marrow cell suspensions (prepared from syngeneic nonirradiated mice) within 2 wk after TLI effectively prevented the autoimmune development. Depletion of T cells from the inocula abrogated the preventive activity. CD4 + T cells mediated the autoimmune prevention but CD8 + T cells did not. CD4 + T cells also appeared to mediate the TLI-induced autoimmune disease because CD4 + T cells from disease-bearing TLI mice adoptively transferred the autoimmune disease to syngeneic naive mice. Taken together, these results indicate that high dose, fractionated ionizing radiation on the lymphoid organs/tissues can cause autoimmune disease by affecting the T cell immune system, rather than the target self-Ags, presumably by altering T cell-dependent control of self-reactive T cells. 62 refs., 9 figs., 2 tabs

  17. Six fractions per week of external beam radiotherapy and high-dose-rate brachytherapy for carcinoma of the uterine cervix: A phase I/II study

    International Nuclear Information System (INIS)

    Yoon, Sang Min; Huh, Seung Jae; Park, Won; Lee, Jeung Eun; Park, Young Je; Nam, Hee Rim; Lim, Do Hoon; Ahn, Yong Chan

    2006-01-01

    Purpose: This study evaluated the treatment results of external beam radiotherapy administered in six fractions per week and high-dose-rate (HDR) brachytherapy for the treatment of cervical cancer. Methods and Materials: From July 2000 to July 2003, 43 patients were enrolled in this study. The patients received 45 Gy from a 10-MV photon beam using four-field box or anterior-posterior beams. Parametrial regions and the pelvic side walls were boosted with up to 50.4 Gy using a midline block. The daily fraction dose was 1.8 Gy administered in six-weekly fractions, from Monday to Saturday. HDR brachytherapy was also delivered at doses of 24 Gy to point A in six fractions twice a week. The median follow-up time was 37 months (range, 9-60 months). Results: The median overall treatment time was 51 days for all patients (range, 44-62 days). Thirty-four patients (79.1%) achieved complete remission and 8 (18.6%) achieved partial remission after radiotherapy. Locoregional recurrence occurred in 5 patients (11.6%), and a distant metastasis was encountered in 6 patients (13.9%). The 3-year overall survival, locoregional, and distant metastasis-free survival rates were 74.7%, 87.8%, and 84.7%, respectively. Grade 2 and 3 late rectal complications were encountered in 3 (6.5%) and 1 (2.2%), respectively. There were no Grade 3 late bladder complications. Conclusions: Six fractions per week of external beam radiotherapy and HDR brachytherapy is an effective treatment for patients with a carcinoma of the uterine cervix and can be used as a possible alternative to concomitant chemoradiotherapy in elderly patients or in patients with co-morbidity

  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. 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

    International Nuclear Information System (INIS)

    Kirchheiner, Kathrin; Czajka-Pepl, Agnieszka; Ponocny-Seliger, Elisabeth; Scharbert, Gisela; Wetzel, Léonore; Nout, Remi A.; Sturdza, Alina; Dimopoulos, Johannes C.; Dörr, Wolfgang; Pötter, Richard

    2014-01-01

    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

  20. Mature results of a randomized trial comparing two fractionation schedules of high dose rate endoluminal brachytherapy for the treatment of endobronchial tumors

    International Nuclear Information System (INIS)

    Niemoeller, Olivier M; Pöllinger, Barbara; Niyazi, Maximilian; Corradini, Stefanie; Manapov, Farkhad; Belka, Claus; Huber, Rudolf M

    2013-01-01

    To determine the efficacy of high dose rate endobronchial brachytherapy (HDR-BT) for the treatment of centrally located lung tumors, two different fractionation schedules were compared regarding local tumor response, side effects and survival. Mature retrospective results with longer follow-up and more patients were analyzed. Initial results were published by Huber et al. in 1995. 142 patients with advanced, centrally located malignant tumors with preferential endoluminal growth were randomized to receive 4 fractions of 3.8 Gy (time interval: 1 week, n = 60, group I) or 2 fractions of 7.2 Gy (time interval: 3 weeks, n = 82, group II) endobronchial HDR-BT. Age, gender, tumor stage, Karnofsky Performance Score and histology were equally distributed between both groups. Local tumor response with 2 fractions of 7.2 Gy was significantly higher as compared to 4 fractions of 3.8 Gy (median 12 vs. 6 weeks; p ≤ 0.015). Median survival was similar in both groups (19 weeks in the 4 fractions group vs. 18 weeks in the 2 fractions group). Fatal hemoptysis was less frequent following irradiation with 2 × 7.2 Gy than with 4 × 3.8 Gy, although the difference did not achieve statistical significance (12.2% vs. 18.3%, respectively. p = 0,345). Patients presenting with squamous cell carcinoma were at higher risk of bleeding compared to other histology (21.9% vs. 9%, p = 0,035). Multivariate analysis with regard to overall survival, revealed histology (p = 0.02), Karnofsky Performance Score (p < 0.0001) and response to therapy (p < 0.0001) as significant prognostic factors. For patients showing complete response the median survival was 57 weeks, while for patients with progressive disease median survival time was 8 weeks, p < 0.0001. The KPS at the start of the treatment was significantly correlated with survival. Patients presenting with a KPS ≤ 60 at the start had a significantly (p = 0,032) shorter survival time (10 weeks) than patients with a KPS > 60 (29 weeks). Moreover

  1. High-dose total-body irradiation and autologous marrow reconstitution in dogs: dose-rate-related acute toxicity and fractionation-dependent long-term survival

    International Nuclear Information System (INIS)

    Deeg, H.J.; Storb, R.; Weiden, P.L.; Schumacher, D.; Shulman, H.; Graham, T.; Thomas, E.D.

    1981-01-01

    Beagle dogs treated by total-body irradiation (TBI) were given autologous marrow grafts in order to avoid death from marrow toxicity. Acute and delayed non-marrow toxicities of high single-dose (27 dogs) and fractionated TBI (20 dogs) delivered at 0.05 or 0.1 Gy/min were compared. Fractionated TBI was given in increments of 2 Gy every 6 hr for three increments per day. Acute toxicity and early mortality (<1 month) at identical total irradiation doses were comparable for dogs given fractionated or single-dose TBI. With single-dose TBI, 14, 16, and 18 Gy, respectively, given at 0.05 Gy/min, 0/5, 5/5, and 2/2 dogs died from acute toxicity; with 10, 12, and 14 Gy, respectively, given at 0.1 Gy/min, 1/5, 4/5, and 5/5 dogs died acutely. With fractionated TBI, 14 and 16 Gy, respectively, given at 0.1 Gy/min, 1/5, 4/5, and 2/2 dogs died auctely. Early deaths were due to radiation enteritis with or without associated septicemia (29 dogs; less than or equal to Day 10). Three dogs given 10 Gy of TBI at 0.1 Gy/min died from bacterial pneumonia; one (Day 18) had been given fractionated and two (Days 14, 22) single-dose TBI. Fifteen dogs survived beyond 1 month; eight of these had single-dose TBI (10-14 Gy) and all died within 7 months of irradiation from a syndrome consisting of hepatic damage, pancreatic fibrosis, malnutrition, wasting, and anemia. Seven of the 15 had fractionated TBI, and only one (14 Gy) died on Day 33 from hepatic failure, whereas 6 (10-14 Gy) are alive and well 250 to 500 days after irradiation. In conclusion, fractionated TBI did not offer advantages over single-dose TBI with regard to acute toxicity and early mortality; rather, these were dependent upon the total dose of TBI. The total acutely tolerated dose was dependent upon the exposure rate; however, only dogs given fractionated TBI became healthy long-term survivors

  2. High-dose 8% capsaicin patch in treatment of chemotherapy-induced peripheral neuropathy: single-center experience.

    Science.gov (United States)

    Filipczak-Bryniarska, Iwona; Krzyzewski, Roger M; Kucharz, Jakub; Michalowska-Kaczmarczyk, Anna; Kleja, Justyna; Woron, Jarosław; Strzepek, Katarzyna; Kazior, Lucyna; Wordliczek, Jerzy; Grodzicki, Tomasz; Krzemieniecki, Krzysztof

    2017-08-17

    High-dose capsaicin patch is effective in treatment of neuropathic pain in HIV-associated neuropathy and diabetic neuropathy. There are no studies assessing effectiveness of high-dose capsaicin patch in treatment of chemotherapy-induced peripheral neuropathy. We sought to determine the effectiveness of treatment of pain associated with chemotherapy-induced peripheral neuropathy with high-dose capsaicin patch. Our study group consisted of 18 patients with clinically confirmed oxaliplatin-induced neuropathy. Baseline characteristic including underling disease, received cumulative dose of neurotoxic agent, neuropathic symptoms, prior treatment and initial pain level were recorded. Pain was evaluated with Numeric Rating Scale prior to treatment with high-dose capsaicin and after 1.8 day and after 8 and 12 weeks after introducing treatment. Patients were divided into two groups accordingly to the amount of neurotoxic agent that caused neuropathy (high sensitivity and low sensitivity group). Most frequent symptoms of chemotherapy-induced neuropathy were: pain (88.89%), paresthesis (100%), sock and gloves sensation (100%) and hypoesthesis (100%). Initial pain level was 7.45 ± 1.14. Mean cumulative dose of oxaliplatin after which patients developed symptoms was 648.07 mg/m 2 . Mean pain level after 12 weeks of treatment was 0.20 ± 0.41. When examined according to high and low sensitivity to neurotoxic agent patients with low sensitivity had higher pain reduction, especially after 8 days after introducing treatment (69.55 ± 12.09 vs. 49.40 ± 20.34%; p = 0.02) and after 12 weeks (96.96 ± 5.56 vs. 83.93 ± 18.59%; p = 0.04). High-dose capsaicin patch is an effective treatment for pain associated with chemotherapy-induced neuropathy in patients treated with oxaliplatin. Patients with lower sensitivity to neurotoxic agents have better response to treatment and pain reduction.

  3. Dose rate-dependent marrow toxicity of TBI in dogs and marrow sparing effect at high dose rate by dose fractionation.

    Science.gov (United States)

    Storb, R; Raff, R F; Graham, T; Appelbaum, F R; Deeg, H J; Schuening, F G; Sale, G; Seidel, K

    1999-01-01

    We evaluated the marrow toxicity of 200 and 300 cGy total-body irradiation (TBI) delivered at 10 and 60 cGy/min, respectively, in dogs not rescued by marrow transplant. Additionally, we compared toxicities after 300 cGy fractionated TBI (100 cGy fractions) to that after single-dose TBI at 10 and 60 cGy/min. Marrow toxicities were assessed on the basis of peripheral blood cell count changes and mortality from radiation-induced pancytopenia. TBI doses studied were just below the dose at which all dogs die despite optimal support. Specifically, 18 dogs were given single doses of 200 cGy TBI, delivered at either 10 (n=13) or 60 (n=5) cGy/min. Thirty-one dogs received 300 cGy TBI at 10 cGy/min, delivered as either single doses (n=21) or three fractions of 100 cGy each (n=10). Seventeen dogs were given 300 cGy TBI at 60 cGy/min, administered either as single doses (n=5) or three fractions of 100 cGy each (n=10). Within the limitations of the experimental design, three conclusions were drawn: 1) with 200 and 300 cGy single-dose TBI, an increase of dose rate from 10 to 60 cGy/min, respectively, caused significant increases in marrow toxicity; 2) at 60 cGy/min, dose fractionation resulted in a significant decrease in marrow toxicities, whereas such a protective effect was not seen at 10 cGy/min; and 3) with fractionated TBI, no significant differences in marrow toxicity were seen between dogs irradiated at 60 and 10 cGy/min. The reduced effectiveness of TBI when a dose of 300 cGy was divided into three fractions of 100 cGy or when dose rate was reduced from 60 cGy/min to 10 cGy/min was consistent with models of radiation toxicity that allow for repair of sublethal injury in DNA.

  4. Adjuvant single-fraction radiotherapy is safe and effective for intractable keloids

    International Nuclear Information System (INIS)

    Song, Changhoon; Wu, Honggyun; Chang, Hak; Kim, Il Han; Ha, Sung W.

    2014-01-01

    The aim of this study was to assess the feasibility and efficacy of high-dose, single-fraction electron beam radiotherapy for therapy-resistant keloids. Before 2010, intractable keloids were treated at our institution with post-operative irradiation of 6-15 Gy in 3-5 fractionations. For convenience and cost effectiveness, we have changed our treatment protocol to high-dose single-fraction radiotherapy. A total of 12 patients with 16 keloid lesions were treated from January 2010 to January 2013 in our department. A 10-Gy dose of electron irradiation was given within 72 h of the surgical excision. The mean follow-up period was 20 months. Treatments were well tolerated, and there was no recurrence in any of the patients. Severe adverse effects were not observed. Surgical excision of the keloid, followed by immediate, single-fraction, high-dose radiotherapy, is both safe and effective in preventing recurrence of therapy-resistant keloids. (author)

  5. Iron concentration in breast milk normalised within one week of a single high-dose infusion of iron isomaltoside in randomised controlled trial

    DEFF Research Database (Denmark)

    Holm, Charlotte; Thomsen, Lars Lykke; Nørgaard, Astrid

    2017-01-01

    AIM: We compared the iron concentration in breast milk after a single high-dose of intravenous iron isomaltoside or daily oral iron for postpartum haemorrhage. METHODS: In this randomised controlled trial, the women were allocated a single dose of intravenous 1,200mg iron isomaltoside or oral iron...... deviation) iron concentration in breast milk in the intravenous and oral groups were 0.72 ± 0.27 mg/L and 0.40 ± 0.18 mg/L at three days (p birth. CONCLUSION: A single high...

  6. Meta-analysis on the Safety and Efficacy of the Reperfusion Use of a Single High Dose of Anti-T-Lymphocyte Globulin Fresenius in Kidney Transplantation.

    Science.gov (United States)

    Du, X; Wang, W; Sun, Z-J; Su, L L; Zhang, X-D

    2016-01-01

    The aim of this study was to evaluate the effects of a single high dose of the anti-T-lymphocyte globulin Fresenius (ATG-F), given before kidney transplantation, on the prevention of acute rejection response and infections and on the survival rate of the renal graft and patient. Databases including PubMed, Embase, and the Cochrane Library were searched to identify randomized controlled trials relevant to studying the presurgical use of a single high dose of ATG-F. Five RCTs that included 346 patients were selected. The meta-analysis suggested that the application of ATG-F reduced the postsurgical acute rejection reaction incidence compared to that of the control group (relative risk = 0.50, 95% confidence interval = 0.35-0.71, P = .0001). However, the application of ATG-F exhibited no significant effect on the incidence of urinary tract infection, cytomegalovirus infection, and delayed graft function. Furthermore, the one-year patient survival rate and kidney graft survival rate were not affected. The meta-analysis suggested that the reperfusion use of a single high dose (9 mg/kg) of ATG-F could effectively reduce the incidence of postsurgical acute rejection response without affecting the occurrence of infections, the survival rates of kidney grafts and patients, or the incidence of delayed graft function. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  7. 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

    International Nuclear Information System (INIS)

    Singh, Anurag K; Godette, Denise J; Stall, Bronwyn R; Coleman, C Norman; Camphausen, Kevin; Ménard, Cynthia; Guion, Peter; Susil, Robert C; Citrin, Deborah E; Ning, Holly; Miller, Robert W; Ullman, Karen; Smith, Sharon; Crouse, Nancy Sears

    2006-01-01

    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. 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. 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. 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

  8. Identification of radiation response genes and proteins from mouse pulmonary tissues after high-dose per fraction irradiation of limited lung volumes.

    Science.gov (United States)

    Jin, Hee; Jeon, Seulgi; Kang, Ga-Young; Lee, Hae-June; Cho, Jaeho; Lee, Yun-Sil

    2017-02-01

    The molecular effects of focal exposure of limited lung volumes to high-dose per fraction irradiation (HDFR) such as stereotactic body radiotherapy (SBRT) have not been fully characterized. In this study, we used such an irradiation system and identified the genes and proteins after HDFR to mouse lung, similar to those associated with human therapy. High focal radiation (90 Gy) was applied to a 3-mm volume of the left lung of C57BL6 mice using a small-animal stereotactic irradiator. As well as histological examination for lungs, a cDNA micro array using irradiated lung tissues and a protein array of sera were performed until 4 weeks after irradiation, and radiation-responsive genes and proteins were identified. For comparison, the long-term effects (12 months) of 20 Gy radiation wide-field dose to the left lung were also investigated. The genes ermap, epb4.2, cd200r3 (up regulation) and krt15, hoxc4, gdf2, cst9, cidec, and bnc1 (down-regulation) and the proteins of AIF, laminin, bNOS, HSP27, β-amyloid (upregulation), and calponin (downregulation) were identified as being responsive to 90 Gy HDFR. The gdf2, cst9, and cidec genes also responded to 20 Gy, suggesting that they are universal responsive genes in irradiated lungs. No universal proteins were identified in both 90 Gy and 20 Gy. Calponin, which was downregulated in protein antibody array analysis, showed a similar pattern in microarray data, suggesting a possible HDFR responsive serum biomarker that reflects gene alteration of irradiated lung tissue. These genes and proteins also responded to the lower doses of 20 Gy and 50 Gy HDFR. These results suggest that identified candidate genes and proteins are HDFR-specifically expressed in lung damage induced by HDFR relevant to SBRT in humans.

  9. Autologous stem cell transplantation following high-dose whole-body irradiation of dogs - influence of cell number and fractionation regimes

    International Nuclear Information System (INIS)

    Bodenberger, U.

    1981-01-01

    The acute radiation syndrome after a single dose of 1600 R (approx. 12-14 Gy in body midline) and after fractionated irradiation with 2400 R (approx. 18-20 Gy) was studied with regard to fractionation time and to the number of bone marrow cells infused. The acute radiation syndrome consisted of damage to the alimentary tract and of damage to the hemopoietic system. Damage of hemopoiesis was reversible in dogs which had been given a sufficient amount of hemopoietic cells. Furthermore changes in skin and in the mucous membranes occurred. Hemopoietic recovery following infusion of various amounts of bone marrow was investigated in dogs which were irradiated with 2400 R within 7 days. Repopulation of bone marrow as well as rise of leukocyte and platelet counts in the peripheral blood was taken as evidence of complete hemopoietic reconstitution. The results indicate that the acute radiation syndrom following 2400 R TBI and autologous BMT can be controlled by fractionation of this dose within 5 or 7 days. The acute gastrointestinal syndrome is aggravated by infusion of a lesser amount of hemopoietic cells. However, TBI with 2400 R does not require greater numbers of hemopoietic cells for restoration of hemopoiesis. Thus, the hemopoiesis supporting tissue can not be damage by this radiation dose to an essential degree. Longterm observations have not revealed serious late defects which could represent a contraindication to the treatment of malignent diseases with 2400 R of TBI. (orig./MG) [de

  10. Acoustic neuromas: single dose vs fractionated therapy

    Energy Technology Data Exchange (ETDEWEB)

    Fuss, M; Debus, J; Lohr, F; Engenhart-Cabillic, R; Wannenmacher, M

    1997-07-01

    Purpose: Radiosurgical treatment (RS) of acoustic neuromas is a well established treatment. However, few data are available concerning conformal fractionated radiotherapy (FT) of this tumor entity. We evaluated treatment outcome and toxicity for both treatment modalities in 41 patients treated at our institution between 1984 and 1997. Material and Methods: All treatments were performed using a specially adapted linear accelerator and circular collimators for convergent beam RS or multi-leaf collimators (leaf thickness 1 or 3mm) for multi-field RS or fractionated treatment. 22 patients (7 male, 15 female, median age 60 years, range 20-83 years) were treated radiosurgically with single doses between 7 and 28 Gray (median 15 Gy) prescribed to the 80% isodose line. Tumor volumes ranged from 0.7 to 10.5 ccm with a median volume of 3.4 ccm. The median number of isocenters was 2 (1-4 isocenters). One patient was treated by a multi-field technique (14 isocentric irregularly shaped noncoplanar fields). 19 patients (5 male, 14 female, median age 55 years, range 20-81 years) were treated with stereotactic conformal radiotherapy. Median dose was 60 Gray with a median daily fraction size of 2 Gy and a median of 3 (1-4) irregularly shaped isocentric fields. Tumor volumes ranged from 0.7 to 32.4 ccm (median 15 ccm). Median follow-up was 30 months (7-149 months) for radiosurgical and 30 months (2-88 months) for fractionated treatment. Seven patients who underwent fractionated treatment had previously undergone neurosurgical resection on the contralateral side. One had undergone radiosurgery on the opposite side before. Results: All tumors were locally controlled. A volume reduction of more than 20% was seen in 16% after RS and 18% following FT. Typical posttherapeutic central reduction of contrast media enhancement was found in 73% following RS after a median of 8 (3-12) months and in 63% following FT after a median of 6 (1-12) months. Temporary brainstem edema was diagnosed in 4

  11. Factors impacting short and long-term kidney graft survival: modification by single intra-operative -high-dose induction with ATG-Fresenius.

    Science.gov (United States)

    Kaden, Jürgen; May, Gottfried; Völp, Andreas; Wesslau, Claus

    2011-01-01

    A majority of recipients benefited from the intra-operative single high-dose induction (HDI) with ATG-Fresenius (ATG-F) still leaving a group of recipients who did not profit from this kind of induction. Therefore the aim of this retrospective analysis was 1st to identify the risk factors impacting short and long-term graft survival, and 2nd to assess the efficacy of this type of induction in kidney graft recipients with or without these risk factors. A total of 606 recipients receiving two different immunosuppressive treatment regimens (1st: Triple drug therapy [TDT, n=196] consisting mainly of steroids, azathioprine and cyclosporine; 2nd: TDT + 9 mg/kg ATG-F intra-operatively [HDI, n=410]) were included in this analysis and grouped according to their kidney graft survival time (short GST: ≤1 yr, n=100 and long GST: >5 yrs, n=506). The main risk factors associated with a shortened graft survival were pre-transplant sensitization, re-transplantation, rejections (in particular vascular or mixed ones) and the necessity of a long-term anti-rejection therapy. Adding ATG-F single high dose induction to TDT was more efficient in prolonging kidney graft survival than TDT alone not only in recipients without any risk factors (p<0.005) but also in recipients with at least one risk factor (p<0.021). Only in 4.6% of recipients having two or more risk factors this effect could not be demonstrated. The intra-operative single high-dose induction with ATG-F significantly improves the kidney graft survival in recipients with or without risk factors and can therefore be recommended.

  12. Acoustic neuromas: single dose vs fractionated therapy

    International Nuclear Information System (INIS)

    Fuss, M.; Debus, J.; Lohr, F.; Engenhart-Cabillic, R.; Wannenmacher, M.

    1997-01-01

    Purpose: Radiosurgical treatment (RS) of acoustic neuromas is a well established treatment. However, few data are available concerning conformal fractionated radiotherapy (FT) of this tumor entity. We evaluated treatment outcome and toxicity for both treatment modalities in 41 patients treated at our institution between 1984 and 1997. Material and Methods: All treatments were performed using a specially adapted linear accelerator and circular collimators for convergent beam RS or multi-leaf collimators (leaf thickness 1 or 3mm) for multi-field RS or fractionated treatment. 22 patients (7 male, 15 female, median age 60 years, range 20-83 years) were treated radiosurgically with single doses between 7 and 28 Gray (median 15 Gy) prescribed to the 80% isodose line. Tumor volumes ranged from 0.7 to 10.5 ccm with a median volume of 3.4 ccm. The median number of isocenters was 2 (1-4 isocenters). One patient was treated by a multi-field technique (14 isocentric irregularly shaped noncoplanar fields). 19 patients (5 male, 14 female, median age 55 years, range 20-81 years) were treated with stereotactic conformal radiotherapy. Median dose was 60 Gray with a median daily fraction size of 2 Gy and a median of 3 (1-4) irregularly shaped isocentric fields. Tumor volumes ranged from 0.7 to 32.4 ccm (median 15 ccm). Median follow-up was 30 months (7-149 months) for radiosurgical and 30 months (2-88 months) for fractionated treatment. Seven patients who underwent fractionated treatment had previously undergone neurosurgical resection on the contralateral side. One had undergone radiosurgery on the opposite side before. Results: All tumors were locally controlled. A volume reduction of more than 20% was seen in 16% after RS and 18% following FT. Typical posttherapeutic central reduction of contrast media enhancement was found in 73% following RS after a median of 8 (3-12) months and in 63% following FT after a median of 6 (1-12) months. Temporary brainstem edema was diagnosed in 4

  13. A single high dose of escitalopram increases mismatch negativity without affecting processing negativity or P300 amplitude in healthy volunteers

    DEFF Research Database (Denmark)

    Wienberg, M; Glenthøj, Birte Yding; Jensen, K S

    2009-01-01

    processing. The present study was designed to replicate and further extent the results of our initial study on the effects of a low dose of escitalopram (10 mg) on MMN, PN and P300 amplitude. In a randomised, double-blind, cross-over experiment, 20 healthy male volunteers received either a single, orally...... administered dose of 15 mg escitalopram (a highly selective serotonin reuptake inhibitor (SSRI)) or placebo, after which their PN, MMN and P300 amplitude were assessed. Similar to our initial study with 10 mg escitalopram, 15 mg escitalopram significantly increased MMN, while it did not affect P300 amplitude....... In contrast to our initial study, however, the currently higher dose of escitalopram did not increase PN. Results support the view that a broad range of increased serotonergic activity enhances MMN, while the relationship between serotonin and PN seems more complex. The current study does not support...

  14. Pharmacokinetic Evaluation of a Single Intramuscular High Dose versus an Oral Long-Term Supplementation of Cholecalciferol.

    Directory of Open Access Journals (Sweden)

    Katharina Wylon

    Full Text Available Vitamin D deficiency is frequent during the winter and occurs throughout the year in the elderly or patients suffering from autoimmune diseases. The objective of this study was to evaluate the pharmacokinetic properties of oral supplementation versus a single intramuscular injection of cholecalciferol in healthy individuals.Up to 8,000 I.U. oral cholecalciferol was administered daily for 84 days in a 4 week dose-escalation setting to vitamin D deficient individuals. In another cohort, a single intramuscular injection of 100,000 I.U. cholecalciferol was given. In both cohorts, individuals without vitamin D intake served as the comparison group. 25-hydroxyvitamin D (25(OHD concentrations were measured in all individuals at defined time points throughout the studies.The mean 25(OHD serum concentration increased significantly after oral cholecalciferol intake compared to the control group (day 28: 83.4 nmol/l and 42.5 nmol/l; day 56: 127.4 nmol/l and 37.3 nmol/l; day 84: 159.7 nmol/l and 30.0 nmol/l. In individuals receiving 100,000 I.U. cholecalciferol intramuscular, the mean 25(OHD serum concentration peaked after 4 weeks measuring 70.9 nmol/l compared to 32.7 nmol/l in the placebo group (p = 0.002. The increase of 25(OHD serum concentrations after 28 days was comparable between both routes of administration (p = 0.264.Oral and intramuscular cholecalciferol supplementation effectively increased serum 25(OHD concentrations.

  15. Universal Survival Curve and Single Fraction Equivalent Dose: Useful Tools in Understanding Potency of Ablative Radiotherapy

    International Nuclear Information System (INIS)

    Park, Clint; Papiez, Lech; Zhang Shichuan; Story, Michael; Timmerman, Robert D.

    2008-01-01

    Purpose: Overprediction of the potency and toxicity of high-dose ablative radiotherapy such as stereotactic body radiotherapy (SBRT) by the linear quadratic (LQ) model led to many clinicians' hesitating to adopt this efficacious and well-tolerated therapeutic option. The aim of this study was to offer an alternative method of analyzing the effect of SBRT by constructing a universal survival curve (USC) that provides superior approximation of the experimentally measured survival curves in the ablative, high-dose range without losing the strengths of the LQ model around the shoulder. Methods and Materials: The USC was constructed by hybridizing two classic radiobiologic models: the LQ model and the multitarget model. We have assumed that the LQ model gives a good description for conventionally fractionated radiotherapy (CFRT) for the dose to the shoulder. For ablative doses beyond the shoulder, the survival curve is better described as a straight line as predicted by the multitarget model. The USC smoothly interpolates from a parabola predicted by the LQ model to the terminal asymptote of the multitarget model in the high-dose region. From the USC, we derived two equivalence functions, the biologically effective dose and the single fraction equivalent dose for both CFRT and SBRT. Results: The validity of the USC was tested by using previously published parameters of the LQ and multitarget models for non-small-cell lung cancer cell lines. A comparison of the goodness-of-fit of the LQ and USC models was made to a high-dose survival curve of the H460 non-small-cell lung cancer cell line. Conclusion: The USC can be used to compare the dose fractionation schemes of both CFRT and SBRT. The USC provides an empirically and a clinically well-justified rationale for SBRT while preserving the strengths of the LQ model for CFRT

  16. Impedance matching through a single passive fractional element

    KAUST Repository

    Radwan, Ahmed Gomaa

    2012-07-01

    For the first time, a generalized admittance Smith chart theory is introduced to represent fractional order circuit elements. The principles of fractional order matching circuits are described. We show that for fractional order α < 1, a single parallel fractional element can match a wider range of load impedances as compared to its series counterpart. Several matching examples demonstrate the versatility of fractional order series and parallel element matching as compared to the conventional approach. © 2012 IEEE.

  17. Single fraction versus multiple fraction radiotherapy for palliation of painful vertebral bone metastases: A prospective study

    Directory of Open Access Journals (Sweden)

    Dipanjan Majumder

    2012-01-01

    Conclusions: Different fractionation of radiation has same response and toxicity in treatment of vertebral bone metastasis. Single fraction RT may be safely used to treat these cases as this is more cost effective and less time consuming. Studies may be conducted to find out particular subgroup of patients to be benefitted more by either fractionation schedule; however, our study cannot comment on that issue.

  18. Single-fraction vs. fractionated linac-based stereotactic radiosurgery for vestibular schwannoma: a single-institution study

    NARCIS (Netherlands)

    Meijer, O. W. M.; Vandertop, W. P.; Baayen, J. C.; Slotman, B. J.

    2003-01-01

    PURPOSE: In this single-institution trial, we investigated whether fractionated stereotactic radiation therapy is superior to single-fraction linac-based radiosurgery with respect to treatment-related toxicity and local control in patients with vestibular schwannoma. METHODS AND MATERIALS: All 129

  19. Real-time Tumor Oxygenation Changes After Single High-dose Radiation Therapy in Orthotopic and Subcutaneous Lung Cancer in Mice: Clinical Implication for Stereotactic Ablative Radiation Therapy Schedule Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Song, Changhoon [Department of Radiation Oncology, Seoul National University College of Medicine, Seoul (Korea, Republic of); Hong, Beom-Ju; Bok, Seoyeon; Lee, Chan-Ju; Kim, Young-Eun [Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang, Gyeongbuk (Korea, Republic of); Jeon, Sang-Rok [Department of Radiation Oncology, Seoul National University College of Medicine, Seoul (Korea, Republic of); Cancer Research Institute, Seoul National University College of Medicine, Seoul (Korea, Republic of); Wu, Hong-Gyun [Department of Radiation Oncology, Seoul National University College of Medicine, Seoul (Korea, Republic of); Cancer Research Institute, Seoul National University College of Medicine, Seoul (Korea, Republic of); Institute of Radiation Medicine, Medical Research Center, Seoul National University College of Medicine, Seoul (Korea, Republic of); Lee, Yun-Sang [Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul (Korea, Republic of); Department of Molecular Medicine and Biopharmaceutical Sciences, Seoul National University College of Medicine, Seoul (Korea, Republic of); Cheon, Gi Jeong; Paeng, Jin Chul [Cancer Research Institute, Seoul National University College of Medicine, Seoul (Korea, Republic of); Institute of Radiation Medicine, Medical Research Center, Seoul National University College of Medicine, Seoul (Korea, Republic of); Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul (Korea, Republic of); Carlson, David J. [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States); and others

    2016-07-01

    Purpose: To investigate the serial changes of tumor hypoxia in response to single high-dose irradiation by various clinical and preclinical methods to propose an optimal fractionation schedule for stereotactic ablative radiation therapy. Methods and Materials: Syngeneic Lewis lung carcinomas were grown either orthotopically or subcutaneously in C57BL/6 mice and irradiated with a single dose of 15 Gy to mimic stereotactic ablative radiation therapy used in the clinic. Serial [{sup 18}F]-misonidazole (F-MISO) positron emission tomography (PET) imaging, pimonidazole fluorescence-activated cell sorting analyses, hypoxia-responsive element-driven bioluminescence, and Hoechst 33342 perfusion were performed before irradiation (day −1), at 6 hours (day 0), and 2 (day 2) and 6 (day 6) days after irradiation for both subcutaneous and orthotopic lung tumors. For F-MISO, the tumor/brain ratio was analyzed. Results: Hypoxic signals were too low to quantitate for orthotopic tumors using F-MISO PET or hypoxia-responsive element-driven bioluminescence imaging. In subcutaneous tumors, the maximum tumor/brain ratio was 2.87 ± 0.483 at day −1, 1.67 ± 0.116 at day 0, 2.92 ± 0.334 at day 2, and 2.13 ± 0.385 at day 6, indicating that tumor hypoxia was decreased immediately after irradiation and had returned to the pretreatment levels at day 2, followed by a slight decrease by day 6 after radiation. Pimonidazole analysis also revealed similar patterns. Using Hoechst 33342 vascular perfusion dye, CD31, and cleaved caspase 3 co-immunostaining, we found a rapid and transient vascular collapse, which might have resulted in poor intratumor perfusion of F-MISO PET tracer or pimonidazole delivered at day 0, leading to decreased hypoxic signals at day 0 by PET or pimonidazole analyses. Conclusions: We found tumor hypoxia levels decreased immediately after delivery of a single dose of 15 Gy and had returned to the pretreatment levels 2 days after irradiation and had decreased

  20. Effect of a single intraoperative high-dose ATG-Fresenius on delayed graft function in donation after cardiac-death donor renal allograft recipients: a randomized study.

    Science.gov (United States)

    van den Hoogen, Martijn W F; Kho, Marcia M L; Abrahams, Alferso C; van Zuilen, Arjan D; Sanders, Jan-Stephan; van Dijk, Marja; Hilbrands, Luuk B; Weimar, Willem; Hoitsma, Andries J

    2013-04-01

    Reducing the incidence of delayed graft function after transplant with donation after cardiac death donor renal allografts would facilitate managing recipients during their first weeks after a transplant. To reduce this incidence, in most studies, induction therapy with depleting anti-T-lymphocyte antibodies is coupled with a reduction of the dosage of the calcineurin inhibitor. The separate effect of anti-T-cell therapy on the incidence and duration of delayed graft function is therefore difficult to assess. We performed a randomized study to evaluate the effect of a single intraoperative high-dose of anti-T-lymphocyte immunoglobulin (ATG)-Fresenius (9 mg/kg body weight) on the incidence of delayed graft function. Eligible adult recipients of a first donation after cardiac death donor renal allograft were randomly assigned to ATG-Fresenius or no induction therapy. Maintenance immunosuppression consisted of tacrolimus, in an unadjusted dose, mycophenolate mofetil, and steroids. The study was prematurely terminated because of a lower-than-anticipated inclusion rate. Baseline characteristics were comparable in the ATG-Fresenius group (n=28) and the control group (n=24). Twenty-two patients in the ATG-Fresenius group (79%) had delayed graft function, compared with 13 in the control group (54%; P = .06). Allograft and patient survival were comparable in both groups. Serious adverse events occurred more frequently in the ATG-Fresenius group than they did in the control group (57% vs 29%; P Fresenius in donation after cardiac death donor renal allograft recipients, followed by triple immunosuppression with an unadjusted tacrolimus dose, seems ineffective to reduce the incidence of delayed graft function. Moreover, this was associated with a higher rate of serious adverse events (EudraCT-number, 2007-000210-36.).

  1. The effect of a single early high-dose vitamin D supplement on fracture union in patients with hypovitaminosis D: a prospective randomised trial.

    Science.gov (United States)

    Haines, N; Kempton, L B; Seymour, R B; Bosse, M J; Churchill, C; Hand, K; Hsu, J R; Keil, D; Kellam, J; Rozario, N; Sims, S; Karunakar, M A

    2017-11-01

    To evaluate the effect of a single early high-dose vitamin D supplement on fracture union in patients with hypovitaminosis D and a long bone fracture. Between July 2011 and August 2013, 113 adults with a long bone fracture were enrolled in a prospective randomised double-blind placebo-controlled trial. Their serum vitamin D levels were measured and a total of 100 patients were found to be vitamin D deficient (vitamin D 3 orally (100 000 IU) within two weeks of injury (treatment group, n = 50) or a placebo (control group, n = 50). We recorded patient demographics, fracture location and treatment, vitamin D level, time to fracture union and complications, including vitamin D toxicity. Outcomes included union, nonunion or complication requiring an early, unplanned secondary procedure. Patients without an outcome at 15 months and no scheduled follow-up were considered lost to follow-up. The t -test and cross tabulations verified the adequacy of randomisation. An intention-to-treat analysis was carried out. In all, 100 (89%) patients had hypovitaminosis D. Both treatment and control groups had similar demographics and injury characteristics. The initial median vitamin D levels were 16 ng/mL (interquartile range 5 to 28) in both groups (p = 0.885). A total of 14 patients were lost to follow-up (seven from each group), two had fixation failure (one in each group) and one control group patient developed an infection. Overall, the nonunion rate was 4% (two per group). No patient showed signs of clinical toxicity from their supplement. Despite finding a high level of hypovitaminosis D, the rate of union was high and independent of supplementation with vitamin D 3 . Cite this article: Bone Joint J 2017;99-B:1520-5. ©2017 The British Editorial Society of Bone & Joint Surgery.

  2. Modeling single-file diffusion with step fractional Brownian motion and a generalized fractional Langevin equation

    International Nuclear Information System (INIS)

    Lim, S C; Teo, L P

    2009-01-01

    Single-file diffusion behaves as normal diffusion at small time and as subdiffusion at large time. These properties can be described in terms of fractional Brownian motion with variable Hurst exponent or multifractional Brownian motion. We introduce a new stochastic process called Riemann–Liouville step fractional Brownian motion which can be regarded as a special case of multifractional Brownian motion with a step function type of Hurst exponent tailored for single-file diffusion. Such a step fractional Brownian motion can be obtained as a solution of the fractional Langevin equation with zero damping. Various kinds of fractional Langevin equations and their generalizations are then considered in order to decide whether their solutions provide the correct description of the long and short time behaviors of single-file diffusion. The cases where the dissipative memory kernel is a Dirac delta function, a power-law function and a combination of these functions are studied in detail. In addition to the case where the short time behavior of single-file diffusion behaves as normal diffusion, we also consider the possibility of a process that begins as ballistic motion

  3. Long-term outcomes of high dose treatment and autologous stem cell transplantation in follicular and mantle cell lymphomas – a single centre experience

    Directory of Open Access Journals (Sweden)

    Boltezar Lucka

    2016-06-01

    Full Text Available Advanced follicular lymphoma (FL and mantle cell lymphoma (MCL are incurable diseases with conventional treatment. The high dose treatment (HDT with autologous stem cell transplantation (ASCT, however, offers a certain proportion of these patients the prospect of a prolonged disease-free and overall survival. The aim of this study was to investigate the event free survival (EFS and overall survival (OS in patients with FL and MCL treated with ASCT.

  4. Local progression and pseudo progression after single fraction or fractionated stereotactic radiotherapy for large brain metastases. A single centre study

    Energy Technology Data Exchange (ETDEWEB)

    Wiggenraad, R.; Verbeek-de Kanter, A.; Mast, M. [Radiotherapy Centre West, The Hague (Netherlands); Molenaar, R. [Diaconessenhuis, Leiden (Netherlands). Dept. of Neurology; Lycklama a Nijeholt, G. [Medical Centre Haagladen, The Hague (Netherlands). Dept. of Radiology; Vecht, C. [Medical Centre Haagladen, The Hague (Netherlands). Dept. of Neurology; Struikmans, H. [Radiotherapy Centre West, The Hague (Netherlands); Leiden Univ. Medical Centre (Netherlands). Dept. of Radiotherapy; Kal, H.B.

    2012-08-15

    Purpose: The 1-year local control rates after single-fraction stereotactic radiotherapy (SRT) for brain metastases > 3 cm diameter are less than 70%, but with fractionated SRT (FSRT) higher local control rates have been reported. The purpose of this study was to compare our treatment results with SRT and FSRT for large brain metastases. Materials and methods: In two consecutive periods, 41 patients with 46 brain metastases received SRT with 1 fraction of 15 Gy, while 51 patients with 65 brain metastases received FSRT with 3 fractions of 8 Gy. We included patients with brain metastases with a planning target volume of > 13 cm{sup 3} or metastases in the brainstem. Results: The minimum follow-up of patients still alive was 22 months. Comparing 1 fraction of 15 Gy with 3 fractions of 8 Gy, the 1-year rates of freedom from any local progression (54% and 61%, p = 0.93) and pseudo progression (85% and 75%, p = 0.25) were not significantly different. Overall survival rates were also not different. Conclusion: The 1-year local progression and pseudo progression rates after 1 fraction of 15 Gy or 3 fractions of 8 Gy for large brain metastases and metastases in the brainstem are similar. For better local control rates, FSRT schemes with a higher biological equivalent dose may be necessary. (orig.)

  5. Local progression and pseudo progression after single fraction or fractionated stereotactic radiotherapy for large brain metastases. A single centre study

    International Nuclear Information System (INIS)

    Wiggenraad, R.; Verbeek-de Kanter, A.; Mast, M.; Molenaar, R.; Lycklama a Nijeholt, G.; Vecht, C.; Struikmans, H.; Leiden Univ. Medical Centre; Kal, H.B.

    2012-01-01

    Purpose: The 1-year local control rates after single-fraction stereotactic radiotherapy (SRT) for brain metastases > 3 cm diameter are less than 70%, but with fractionated SRT (FSRT) higher local control rates have been reported. The purpose of this study was to compare our treatment results with SRT and FSRT for large brain metastases. Materials and methods: In two consecutive periods, 41 patients with 46 brain metastases received SRT with 1 fraction of 15 Gy, while 51 patients with 65 brain metastases received FSRT with 3 fractions of 8 Gy. We included patients with brain metastases with a planning target volume of > 13 cm 3 or metastases in the brainstem. Results: The minimum follow-up of patients still alive was 22 months. Comparing 1 fraction of 15 Gy with 3 fractions of 8 Gy, the 1-year rates of freedom from any local progression (54% and 61%, p = 0.93) and pseudo progression (85% and 75%, p = 0.25) were not significantly different. Overall survival rates were also not different. Conclusion: The 1-year local progression and pseudo progression rates after 1 fraction of 15 Gy or 3 fractions of 8 Gy for large brain metastases and metastases in the brainstem are similar. For better local control rates, FSRT schemes with a higher biological equivalent dose may be necessary. (orig.)

  6. High-dose-rate intracavitary brachytherapy (HDR-IC) in treatment of cervical carcinoma: 5-year results and implication of increased low-grade rectal complication on initiation of an HDR-IC fractionation scheme

    International Nuclear Information System (INIS)

    Wang Chongjong; Wan Leung, Stephen; Chen Huichun; Sun Limin; Fang Fumin; Changchien Chanchao; Huang Engyen; Wu Jiaming; Chen Chuhnchih

    1997-01-01

    Purpose: To report the treatment results and rectal/bladder complications of cervical carcinoma radically treated with high-dose-rate intracavitary brachytherapy (HDR-IC). The current policy of using three-fraction scheme was examined. Methods and Materials: Between November 1987 and August 1990, 173 patients with cervical carcinoma were treated with curative-intent radiation therapy. Whole pelvic irradiation was administered with 10-MV X ray. Dose to the central cervix was 40-44 Gy in 20-22 fractions, following by pelvic wall boost 6-14 Gy in three to seven fractions with central shielding. 60 Co sources were used for HDR-IC, and 7.2 Gy was given to Point A for three applications, 1-2 weeks apart. Duration of follow-up was 5-7.8 years. Results: Twenty-eight patients (16%) developed central-regional recurrences. Overall 5-year actuarial pelvic control rate was 83%. By stage, 5-year actuarial pelvic control rates were 94%, 87%, and 72% for Stages IB + IIA, IIB + IIIA, and IIIB + IVA, respectively. Thirty-one patients (18%) developed distant metastasis. Overall 5-year actuarial survival rate was 58%. By stage, 5-year actuarial survival rates were 79%, 59%, and 41% for Stages IB + IIA, IIB + IIIA, and IIIB + IVA, respectively. Sixty-six (38%) and 19 patients (11%) developed rectal and bladder complications, respectively. For rectal complication, the overall actuarial rate was 38% at 5 years. By grade, 5-year actuarial rectal complication rates were 24%, 15%, 4%, and 3% for Grades 1-4, respectively. Overall prevalence of rectal complications was 37% and 14% at 2 and 5 years, respectively. Prevalence of low-grade rectal complication (Grades 1 and 2) was dominant at 2 years (30%), but declined to 8% at 5 years. Prevalence of high-grade, severe rectal complication (Grades 3 and 4) remained steady at 2 and 5 years (7% and 6%, respectively). Five-year actuarial bladder complication was 9%. Five-year prevalence of bladder complication was 2%. Conclusion: Using a three-fraction

  7. High-dose melphalan and autologous stem cell transplantation for AL amyloidosis: recent trends in treatment-related mortality and 1-year survival at a single institution

    Science.gov (United States)

    Seldin, D. C.; Andrea, N.; Berenbaum, I.; Berk, J. L.; Connors, L.; Dember, L. M.; Doros, G.; Fennessey, S.; Finn, K.; Girnius, S.; Lerner, A.; Libbey, C.; Meier-Ewert, H. K.; O’Connell, R.; O’Hara, C.; Quillen, K.; Ruberg, F. L.; Sam, F.; Segal, A.; Shelton, A.; Skinner, M.; Sloan, J. M.; Wiesman, J. F.; Sanchorawala, V.

    2017-01-01

    Treatment with high-dose melphalan chemotherapy supported by hematopoietic rescue with autologous stem cells produces high rates of hematologic responses and improvement in survival and organ function for patients with AL amyloidosis. Ongoing clinical trials explore pre-transplant induction regimens, post-transplant consolidation or maintenance approaches, and compare transplant to non-transplant regimens. To put these studies into context, we reviewed our recent experience with transplant for AL amyloidosis in the Amyloid Treatment and Research Program at Boston Medical Center and Boston University School of Medicine. Over the past 10 years, there was a steady reduction in rates of treatment-related mortality and improvement in 1-year survival, now approximately 5% and 90%, respectively, based upon an intention-to-treat analysis. Median overall survival of patients treated with this approach at our center exceeds 7.5 years. PMID:21838459

  8. Gamma dosimetry of high doses

    International Nuclear Information System (INIS)

    Martinez C, T.; Galvan G, A.; Canizal, G.

    1991-01-01

    The gamma dosimetry of high doses is problematic in almost all the classic dosemeters either based on the thermoluminescence, electric, chemical properties, etc., because they are saturated to very high dose and they are no longer useful. This work carries out an investigation in the interval of high doses. The solid system of heptahydrate ferrous sulfate, can be used as solid dosemeter of routine for high doses of radiation. The proposed method is simple, cheap and it doesn't require sophisticated spectrophotometers or spectrometers but expensive and not common in some laboratories

  9. Feasibility and early outcome of high-dose-rate Ir-192 brachytherapy as monotherapy in two fractions within 1 day for high-/very high-risk prostate cancer.

    Science.gov (United States)

    Ashida, Shingo; Yamasaki, Ichiro; Tamura, Kenji; Shimamoto, Tsutomu; Inoue, Keiji; Kariya, Shinji; Kobayashi, Kana; Yamagami, Takuji; Shuin, Taro

    2016-05-01

    The aim of the present study was to evaluate the feasibility and preliminary outcomes of high-dose-rate (HDR)-brachytherapy as a monotherapy in two fractions within 1 day for localized prostate cancer, including high-/very high-risk cases. Among the 68 patients treated with HDR monotherapy between July 2011 and December 2014, 65 had a minimal follow-up of 12 months without adjuvant androgen deprivation therapy and were enrolled in the present study [42/65 (64.6%) exhibited high-/very high-risk diseases]. HDR monotherapy was performed in two fractions with a minimal interval of 6 h and the prescribed dose was 13.5 Gy (×2). Adverse events (AEs) were assessed using Common Terminology Criteria for Adverse Events (version 4; http://ctep.cancer.gov/protocolDevelopment/electronic_applications/ctc.htm#ctc_40), and biochemical failure was assessed by the Phoenix definition. The median follow-up time was 30.1 months. The majority of patients had Grade 0-1 acute AEs. Four patients (6.2%) exhibited urinary retention, requiring a Foley catheter. Grade 3 acute AEs occurred at a frequency of 3.1% and hematuria at 1.5%. The majority of patients also exhibited Grade 0-1 chronic AEs. Grade 3 chronic AEs occurred at a frequency of 1.5% and urethral stricture at 1.5%, for which endoscopic treatment was indicated. Acute and chronic gastrointestinal AEs were uncommon, and no Grade 3 or above AEs developed. Biochemical failure occurred in 4 patients who all exhibited high-/very high-risk diseases. Kaplan-Meier estimated that 3 year biochemical failure-free survival was 91.6% overall and 88.0% in high-/very high-risk cases. The present two-fraction 1 day HDR monotherapy is feasible with minimal AEs and achieved acceptable biochemical control of localized prostate cancer, including high-/very high-risk cases, although long-term follow-up is required.

  10. Single-fraction stereotactic radiotherapy: a dose-response analysis of arteriovenous malformation obliteration

    International Nuclear Information System (INIS)

    Touboul, Emmanuel; Al Halabi, Assem; Buffat, Laurent; Merienne, Louis; Huart, Judith; Schlienger, Michel; Lefkopoulos, Dimitrios; Mammar, Hamid; Missir, Odile; Meder, Jean-Francois; Laurent, Alex; Housset, Martin

    1998-01-01

    Purpose: Stereotactic radiotherapy delivered in a high-dose single fraction is an effective technique to obliterate intracranial arteriovenous malformations (AVM). To attempt to analyze the relationships between dose, volume, and obliteration rates, we studied a group of patients treated using single-isocenter treatment plans. Methods and Materials: From May 1986 to December 1989, 100 consecutive patients with angiographically proven AVM had stereotactic radiotherapy delivered as a high-dose single fraction using a single-isocenter technique. Distribution according to Spetzler-Martin grade was as follows: 79 grade 1-3, three grade 4, 0 grade 5, and 18 grade 6. The target volume was spheroid in 74 cases, ellipsoid in 11, and large and irregular in 15. The targeted volume of the nidus was estimated using two-dimensional stereotactic angiographic data and, calculated as an ovoid-shaped lesion, was 1900 ± 230 mm 3 (median 968 mm 3 ; range 62-11, 250 mm 3 ). The mean minimum target dose (D min ) was 19 ± 0.6 Gy (median 20 Gy; range: 3-31.5). The mean volume within the isodose which corresponded to the minimum target dose was 2500 ± 300 mm 3 (median 1200 mm 3 ; range 75-14 900 mm 3 ). The mean maximum dose (D max ) was 34.5 ± 0.5 Gy (median 35 Gy; range 15-45). The mean angiographic follow-up was 42 ± 2.3 months (median 37.5; range 7-117). Results: The absolute obliteration rate was 51%. The 5-year actuarial obliteration rate was 62.5 ± 7%. After univariate analysis, AVM obliteration was influenced by previous surgery (p = 0.0007), D min by steps of 5 Gy (p = 0.005), targeted volume of the nidus (≤968 mm 3 vs. >968 mm 3 ; p = 0.015), and grade according to Spetzler-Martin (grade 1-3 vs. grade 4-6; p = 0.011). After multivariate analysis, the independent factors influencing AVM obliteration were the D min [relative risk (RR) 1.9; 95% confidence interval (CI) 1.4-2.5; p min but does not seem to be influenced by D max and the targeted volume of the nidus

  11. Single Fraction Versus Fractionated Linac-Based Stereotactic Radiotherapy for Vestibular Schwannoma: A Single-Institution Experience

    Energy Technology Data Exchange (ETDEWEB)

    Collen, Christine, E-mail: ccollen@uzbrussel.be [Department of Radiation Oncology, UZ Brussel, Vrije Universiteit Brussel (VUB), Laarbeeklaan 101, 1090 Brussels (Belgium); Ampe, Ben [Department of Neurosurgery, UZ Brussel, Vrije Universiteit Brussel (VUB), Laarbeeklaan 101, 1090 Brussels (Belgium); Gevaert, Thierry [Department of Radiation Oncology, UZ Brussel, Vrije Universiteit Brussel (VUB), Laarbeeklaan 101, 1090 Brussels (Belgium); Moens, Maarten [Department of Neurosurgery, UZ Brussel, Vrije Universiteit Brussel (VUB), Laarbeeklaan 101, 1090 Brussels (Belgium); Linthout, Nadine; De Ridder, Mark; Verellen, Dirk [Department of Radiation Oncology, UZ Brussel, Vrije Universiteit Brussel (VUB), Laarbeeklaan 101, 1090 Brussels (Belgium); D' Haens, Jean [Department of Neurosurgery, UZ Brussel, Vrije Universiteit Brussel (VUB), Laarbeeklaan 101, 1090 Brussels (Belgium); Storme, Guy [Department of Radiation Oncology, UZ Brussel, Vrije Universiteit Brussel (VUB), Laarbeeklaan 101, 1090 Brussels (Belgium)

    2011-11-15

    Purpose: To evaluate and compare outcomes for patients with vestibular schwannoma (VS) treated in a single institution with linac-based stereotactic radiosurgery (SRS) or by fractionated stereotactic radiotherapy (SRT). Methods and Materials: One hundred and nineteen patients (SRS = 78, SRT = 41) were treated. For both SRS and SRT, beam shaping is performed by a mini-multileaf collimator. For SRS, a median single dose of 12.5 Gy (range, 11-14 Gy), prescribed to the 80% isodose line encompassing the target, was applied. Of the 42 SRT treatments, 32 treatments consisted of 10 fractions of 3-4 Gy, and 10 patients received 25 sessions of 2 Gy, prescribed to the 100% with the 95% isodose line encompassing the planning target volume. Mean largest tumor diameter was 16.6 mm in the SRS and 24.6 mm in the SRT group. Local tumor control, cranial nerve toxicity, and preservation of useful hearing were recorded. Any new treatment-induced cranial nerve neuropathy was scored as a complication. Results: Median follow-up was 62 months (range, 6-136 months), 5 patients progressed, resulting in an overall 5-year local tumor control of 95%. The overall 5-year facial nerve preservation probability was 88% and facial nerve neuropathy was statistically significantly higher after SRS, after prior surgery, for larger tumors, and in Koos Grade {>=}3. The overall 5-year trigeminal nerve preservation probability was 96%, not significantly influenced by any of the risk factors. The overall 4-year probability of preservation of useful hearing (Gardner-Robertson score 1 or 2) was 68%, not significantly different between SRS or SRT (59% vs. 82%, p = 0.089, log rank). Conclusion: Linac-based RT results in good local control and acceptable clinical outcome in small to medium-sized vestibular schwannomas (VSs). Radiosurgery for large VSs (Koos Grade {>=}3) remains a challenge because of increased facial nerve neuropathy.

  12. Optic nerve tolerance to single and fractionated radiation simulating radiosurgery: a rabbit model using visual evoked potentials, fundoscopy and histology

    International Nuclear Information System (INIS)

    Bastin, Kenneth; Mehta, Minesh

    1997-01-01

    Purpose/Objective: To develop a rabbit model enabling single or fractionated optic nerve irradiation, measure post-irradiation visual evoked potentials (VEP), fundoscopic and histopathologic changes, and relate different radiation dosing fractions to these measurable physiologic changes. Materials and Methods: Forty male New Zealand white rabbits underwent surgical right orbital prolapse with template-guided optic nerve irradiation using an iridium-192 high dose rate afterloader. Rabbits were randomized into single fraction groups (0 (control), 10, 12.5, 15, 20, and 30 Gy (3 per group); or two fraction groups of 0 (control) 5, 7.5, 10, 15, and 20 Gy (3 per group); or three fractions groups of 10 and 15 Gy (2 per group). Bilateral fundoscopy and pattern-reversal VEPs (0.5 and 1 c/deg, 1 hertz) were performed at 6 and 12 months (mos) following scheduled irradiation. VEP peaks (P1) were measured. Sacrifice and necropsy followed 12 month evaluation, allowing for histological changes. Results: Excluding deaths from anesthesia (2), CNS mite infection (2), sepsis, pyothorax, 'undetermined' and technically non-analyzable VEP recordings, 24 complete rabbit data sets were evaluated. Fundoscopy demonstrated no gross changes at any dose. Histopathology demonstrated generalized optic nerve atrophy without radiation dose correlation. Among single fraction groups, VEP showed a 6 mos post-irradiation P1 prolongation only in the 20 and 30 Gy groups (maximum 67%). At 12 mos lower dose single fraction groups had a prolonged P1 peak. All fractionated groups above 5 Gy x 2 had P1 prolongation times at 6 mos (maximum 46% in the 15 Gy x 3 data set) but by 12 mos these groups had non-measurable, deteriorated VEPs. Correlating VEP P1 latency with the calculated linear quadratic formula (LQM) biologically equivalent dose (BED,α/β=3) for each group demonstrated a general correlation (t-Test P<.001) as shown: Conclusion: Using a rabbit model for selective optic nerve irradiation we conclude

  13. Double versus single high-dose melphalan 200 mg/m2 and autologous stem cell transplantation for multiple myeloma: a region-based study in 484 patients from the Nordic area

    Science.gov (United States)

    Björkstrand, Bo; Klausen, Tobias W.; Remes, Kari; Gruber, Astrid; Knudsen, Lene M.; Bergmann, Olav J.; Lenhoff, Stig; Johnsen, Hans E.

    2009-01-01

    Autologous stem cell transplantation is still considered the standard of care in young patients with multiple myeloma (MM). This disease is the most common indication for high-dose therapy (HDT) supported by hematopoietic stem cell transplantation and much data support the benefit of this procedure. Results of randomized studies are in favor of tandem autologous transplantation although the effect on overall survival is unclear. Based on sequential registration trials in the Nordic area, we aimed to evaluate the outcome of conventional single or double HDT. During 1994–2000 we registered a total of 484 previously untreated patients under the age of 60 years at diagnosis who on a regional basis initially were treated with single [Trial NMSG #5/94 and #7/98 (N=383)] or double [Trial Huddinge Karolinska Turku Herlev (N=101)] high-dose melphalan (200 mg/m2) therapy supported by autologous stem cell transplantation. A complete or very good partial response was achieved by 40% of patients in the single transplant group and 60% of patients in the double transplant group (p=0.0006). The probability of surviving progression free for five years after the diagnosis was 25% (95% CL 18–32%) in the singletransplant group and 46% (95% CL 33–55%) in the double transplant group (p=0.0014). The estimated overall five-year survival rate was 60% in the single transplant group and 64% in the doubletransplant (p=0.9). In a multivariate analysis of variables, including single versus double transplantation, β2 microglobulin level, age, sex and disease stage, only β2 microglobulin level was predictive for overall survival (p>0.0001) and progression free survival (p=0.001). In accordance with these results, a 1:1 case-control matched comparison between double and single transplantation did not identify significant differences in overall and progression free survival. In this retrospective analysis up front double transplantation with melphalan (200 mg/m2) as compared to single

  14. A comparative study of quality of life in patients with localized prostate cancer treated at a single institution: Stereotactic ablative radiotherapy or external beam + high dose rate brachytherapy boost

    International Nuclear Information System (INIS)

    Helou, Joelle; Morton, Gerard; Zhang, Liying; Deabreu, Andrea; D’Alimonte, Laura; Elias, Evelyn; Musunuru, Hima Bindu; Mamedov, Alexandre; Ravi, Ananth; Chung, Hans; Cheung, Patrick; Loblaw, Andrew

    2014-01-01

    Purpose: To compare the quality of life (QOL) in patients treated with stereotactic ablative radiation therapy (SABR) alone or high dose rate (HDR) brachytherapy + hypofractionated external beam radiotherapy (EBRT). Methods and materials: Patient self-reported QOL was prospectively measured among patients from two sequential phase 2 clinical trials: 1-SABR 35 Gy/5 fractions/5 weeks, 2–15 Gy HDR 1 fraction, followed by EBRT 37.5 Gy/15 fractions/3 weeks. The expanded prostate cancer index composite was assessed at baseline and q6 monthly up to 5 years. Urinary, bowel and sexual domains were analyzed. A minimally clinical important change (MCIC) was defined as 0.5*standard deviation of the baseline for each domain. Fisher exact test and general linear mixed model were used (p < 0.05). Results: 84 and 123 patients were treated on the SABR and HDR boost studies, with a median follow up of 51 and 61 months respectively. There was a significant difference in MCIC between treatments in the urinary function and bother (p < 0.0001), the bowel function (p = 0.0216) and the sexual function (p = 0.0419) and bother (p = 0.0290) domains in favor of the SABR group. Of patients who reported no problem with their sexual function at baseline, 7% and 23% respectively considered it to be a moderate to big problem on follow up (p = 0.0077). Conclusion: Patients treated with HDR-boost reported deterioration of QOL particularly in sexual domains in comparison with SABR

  15. Single electron probes of fractional quantum hall states

    Science.gov (United States)

    Venkatachalam, Vivek

    When electrons are confined to a two dimensional layer with a perpendicular applied magnetic field, such that the ratio of electrons to flux quanta (nu) is a small integer or simple rational value, these electrons condense into remarkable new phases of matter that are strikingly different from the metallic electron gas that exists in the absence of a magnetic field. These phases, called integer or fractional quantum Hall (IQH or FQH) states, appear to be conventional insulators in their bulk, but behave as a dissipationless metal along their edge. Furthermore, electrical measurements of such a system are largely insensitive to the detailed geometry of how the system is contacted or even how large the system is... only the order in which contacts are made appears to matter. This insensitivity to local geometry has since appeared in a number of other two and three dimensional systems, earning them the classification of "topological insulators" and prompting an enormous experimental and theoretical effort to understand their properties and perhaps manipulate these properties to create robust quantum information processors. The focus of this thesis will be two experiments designed to elucidate remarkable properties of the metallic edge and insulating bulk of certain FQH systems. To study such systems, we can use mesoscopic devices known as single electron transistors (SETs). These devices operate by watching single electrons hop into and out of a confining box and into a nearby wire (for measurement). If it is initially unfavorable for an electron to leave the box, it can be made favorable by bringing another charge nearby, modifying the energy of the confined electron and pushing it out of the box and into the nearby wire. In this way, the SET can measure nearby charges. Alternatively, we can heat up the nearby wire to make it easier for electrons to enter and leave the box. In this way, the SET is a sensitive thermometer. First, by operating the SET as an

  16. R-hyper-CVAD versus R-CHOP/cytarabine with high-dose therapy and autologous haematopoietic stem cell support in fit patients with mantle cell lymphoma: 20 years of single-center experience.

    Science.gov (United States)

    Widmer, Fabienne; Balabanov, Stefan; Soldini, Davide; Samaras, Panagiotis; Gerber, Bernhard; Manz, Markus G; Goede, Jeroen S

    2018-02-01

    Standard of care for untreated mantle cell lymphoma (MCL) is still debated. At the University Hospital Zurich, advanced MCL in physically fit patients is treated either with rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone induction followed by consolidating high-dose chemotherapy and autologous stem cell support (R-CHOP/HD-ASCT), or with rituximab plus fractionated cyclophosphamide, vincristine, doxorubicin and dexamethasone alternating with high-dose methotrexate-cytarabine (R-hyper-CVAD/MTX-AraC) without consolidating HD-ASCT upon physicians' and patients' choice. We retrospectively analysed the outcome and therapy tolerance in patients with MCL treated with R-CHOP/HD-ASCT or R-hyper-CVAD/MTX-AraC at the University Hospital Zurich between January 1996 and January 2016. Forty-three patients were included; 29 patients received R-CHOP/HD-ASCT and 14 patients R-hyper-CVAD/MTX-AraC. Mean age at diagnosis was 54.4 years (range 38-68 years). Thirty-five patients (81.4%) completed the entire first-line therapy (n = 24 in the R-CHOP/HD-ASCT group, n = 11 in the R-hyper-CVAD group). Of those, all patients responded and 97% achieved a complete remission (CR). With a mean follow-up of 5.7 years 10-year progression-free survival (PFS) for all patients was 32% and overall survival (OS) was 76%, with no difference between the two therapy groups. Complication-induced hospitalisation rate, haematological toxicity and economic burden were significantly higher in the R-hyper-CVAD therapy group. In contrast, quality of life and global health state were better in the R-hyper-CVAD therapy group. Both first-line therapies showed similar outcome with a median OS longer than 10 years. Due to significantly lower haematological toxicity and lower economic burden, we recommend R-CHOP/HD-ASCT as first-line therapy in fit adult patients with advanced MCL.

  17. Palliative radiotherapy for painful bone metastases, single versus multiple fraction treatment: a literature review

    International Nuclear Information System (INIS)

    McKee, L.

    2005-01-01

    Palliative radiotherapy provides pain relief for patients with painful bone metastases. The practice among radiation oncologists as to whether a large single fraction is most effective, or whether multiple smaller fractions are preferable in providing the quickest, most durable pain relief is inconsistent. A literature review was completed to see if there is consensus about whether there is better pain response and control following single versus multiple fraction radiotherapy. The Pub Med search engine was used to find all reported studies comparing single and multiple fraction radiotherapy for painful bone metastases. Each article was reviewed according to specific criteria. A generalized conclusion was ascertained from each study and then compared. Among the studies reviewed, the consensus concluded that single fraction radiotherapy was the better choice for palliation of painful bone metastases. According to the literature reviewed, single fraction radiotherapy provides adequate pain relief with reasonable duration of pain response. (author)

  18. 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.

  19. Dosimetric Effects of Air Pockets Around High-Dose Rate Brachytherapy Vaginal Cylinders

    International Nuclear Information System (INIS)

    Richardson, Susan; Palaniswaamy, Geethpriya; Grigsby, Perry W.

    2010-01-01

    Purpose: Most physicians use a single-channel vaginal cylinder for postoperative endometrial cancer brachytherapy. Recent published data have identified air pockets between the vaginal cylinders and the vaginal mucosa. The purpose of this research was to evaluate the incidence, size, and dosimetric effects of these air pockets. Methods and Materials: 25 patients receiving postoperative vaginal cuff brachytherapy with a high-dose rate vaginal cylinders were enrolled in this prospective data collection study. Patients were treated with 6 fractions of 200 to 400 cGy per fraction prescribed at 5 mm depth. Computed tomography simulation for brachytherapy treatment planning was performed for each fraction. The quantity, volume, and dosimetric impact of the air pockets surrounding the cylinder were quantified. Results: In 25 patients, a total of 90 air pockets were present in 150 procedures (60%). Five patients had no air pockets present during any of their treatments. The average number of air pockets per patient was 3.6, with the average total air pocket volume being 0.34 cm 3 (range, 0.01-1.32 cm 3 ). The average dose reduction to the vaginal mucosa at the air pocket was 27% (range, 9-58%). Ten patients had no air pockets on their first fraction but air pockets occurred in subsequent fractions. Conclusion: Air pockets between high-dose rate vaginal cylinder applicators and the vaginal mucosa are present in the majority of fractions of therapy, and their presence varies from patient to patient and fraction to fraction. The existence of air pockets results in reduced radiation dose to the vaginal mucosa.

  20. Marrow toxicity of fractionated vs. single dose total body irradiation is identical in a canine model

    International Nuclear Information System (INIS)

    Storb, R.; Raff, R.F.; Graham, T.; Appelbaum, F.R.; Deeg, H.J.; Schuening, F.G.; Shulman, H.; Pepe, M.

    1993-01-01

    The authors explored in dogs the marrow toxicity of single dose total body irradiation delivered from two opposing 60 Co sources at a rate of 10 cGy/min and compared results to those seen with total body irradiation administered in 100 cGy fractions with minimum interfraction intervals of 6 hr. Dogs were not given marrow transplants. They found that 200 cGy single dose total body irradiation was sublethal, with 12 of 13 dogs showing hematopoietic recovery and survival. Seven of 21 dogs given 300 cGy single dose total body irradiation survived compared to 6 of 10 dogs given 300 cGy fractionated total body irradiation. One of 28 dogs given 400 cGy single dose total body irradiation survived compared to none of six given fractionated radiation. With granulocyte colony stimulating factor (GCSF) administered from day 0-21 after 400 cGy total body irradiation, most dogs survived with hematological recovery. Because of the almost uniform success with GCSF after 400 cGy single dose total body irradiation, a study of GCSF after 400 cGy fractionated total body irradiation was deemed not to be informative and, thus, not carried out. Additional comparisons between single dose and fractionated total body irradiation were carried out with GCSF administered after 500 and 600 cGy of total body irradiation. As with lower doses of total body irradiation, no significant survival differences were seen between the two modes of total body irradiation, and only 3 of 26 dogs studied survived with complete hematological recovery. Overall, therefore, survival among dogs given single dose total body irradiation was not different from that of dogs given fractionated total body irradiation (p = .67). Similarly, the slopes of the postirradiation declines of granulocyte and platelet counts and the rates of their recovery in surviving dogs given equal total doses of single versus fractionated total body irradiation were indistinguishable. 24 refs., 3 figs., 2 tabs

  1. Single Fraction Stereotactic Ablative Body Radiotherapy for Oligometastasis: Outcomes from 132 Consecutive Patients.

    Science.gov (United States)

    Gandhidasan, S; Ball, D; Kron, T; Bressel, M; Shaw, M; Chu, J; Chander, S; Wheeler, G; Plumridge, N; Chesson, B; David, S; Siva, S

    2018-03-01

    Stereotactic ablative body radiotherapy (SABR) is currently used to treat oligometastases, but the optimum dose/fractionation schedule is unknown. In this study, we evaluated outcomes after single fraction SABR in patients with oligometastatic disease. Single institutional retrospective review of patients treated with single fraction SABR for one to three oligometastases between 2010 and 2015. The primary outcome was freedom from widespread disease defined as distant recurrence not amenable to surgery or SABR; or recurrence with four or more metastases. In total, 186 treatments were delivered in 132 patients. The two most common target sites were lung (51%) and bone (40%). The most frequent single fraction prescription dose was 26 Gy (47%). The most common primary malignancy was genitourinary (n = 46 patients). Freedom from widespread disease was 75% at 1 year (95% confidence interval 67-83%) and 52% at 2 years (95% confidence interval 42-63%). Freedom from local progression at 1 year was 90% (95% confidence interval 85-95%) and at 2 years was 84% (95% confidence interval 77-91%). A compression fracture of the lumbar vertebra was the only grade 3+ treatment-related toxicity. Single fraction SABR is associated with a high rate of freedom from widespread disease, favourable local control and low toxicity comparable with historic multi-fraction SABR reports. Copyright © 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  2. Single and 30 fraction tumor control doses correlate in xenografted tumor models: implications for predictive assays

    International Nuclear Information System (INIS)

    Gerweck, Leo E.; Dubois, Willum; Baumann, Michael; Suit, Herman D.

    1995-01-01

    Purpose/Objective: In a previous publication we reported that laboratory assays of tumor clonogen number, in combination with intrinsic radiosensitivity measured in-vitro, accurately predicted the rank-order of single fraction 50% tumor control doses, in six rodent and xenografted human tumors. In these studies, tumor hypoxia influenced the absolute value of the tumor control doses across tumor types, but not their rank-order. In the present study we hypothesize that determinants of the single fraction tumor control dose, may also strongly influence the fractionaled tumor control doses, and that knowledge of tumor clonogen number and their sensitivity to fractionated irradiation, may be useful for predicting the relative sensitivity of tumors treated by conventional fractionated irradiation. Methods/Materials: Five tumors of human origin were used for these studies. Special care was taken to ensure that all tumor control dose assays were performed over the same time frame, i.e., in-vitro cells of a similar passage were used to initiate tumor sources which were expanded and used in the 3rd or 4th generation. Thirty fraction tumor control doses were performed in air breathing mice, under normal blood flow conditions (two fractions/day). The results of these studies have been previously published. For studies under uniformly (clamp) hypoxic conditions, tumors arising from the same transplantation were randomized into single or fractionated dose protocols. For estimation of the fractionated TCD50 under hypoxic conditions, tumors were exposed to six 5.4 Gy fractions (∼ 2 Gy equivalent under air), followed by graded 'top-up' dose irradiation for determination of the TCD50; the time interval between doses was 6-9 hours. The single dose equivalent of the six 5.4 Gy doses was used to calculate an extrapolated 30 fraction hypoxic TCD50. Results: Fractionation substantially increased the dose required for tumor control in 4 of the 5 tumors investigated. For these 4 tumors

  3. Ionization chamber for high dose measurements

    International Nuclear Information System (INIS)

    Rodrigues Junior, Ary de Araujo

    2005-01-01

    Industrial gamma irradiators facilities are designed for processing large amounts of products, which are exposed to large doses of gamma radiation. The irradiation, in industrial scale, is usually carried out in a dynamic form, where the products go through a 60 Co gamma source with activity of TBq to P Bq (k Ci to MCi). The dose is estimated as being directly proportional to the time that the products spend to go through the source. However, in some situations, mainly for research purposes or for validation of customer process following the ISO 11137 requirements, it is required to irradiate small samples in a static position with fractional deliver doses. The samples are put inside the irradiation room at a fixed distance from the source and the dose is usually determined using dosimeters. The dose is only known after the irradiation, by reading the dosimeter. Nevertheless, in the industrial irradiators, usually different kinds of products with different densities go through between the source and the static position samples. So, the dose rate varies in function of the product density. A suitable methodology would be to monitor the samples dose in real time, measuring the dose on line with a radiation detector, which would improve the dose accuracy and avoid the overdose. A cylindrical ionization chamber of 0.9 cm 3 has been developed for high-doses real-time monitoring, during the sample irradiation at a static position in a 60 Co gamma industrial plant. Nitrogen and argon gas at pressure of 10 exp 5 Pa (1 bar) was utilized to fill the ionization chamber, for which an appropriate configuration was determined to be used as a detector for high-dose measurements. To transmit the signal generated in the ionization chamber to the associated electronic and processing unit, a 20 m mineral insulated cable was welded to the ionization chamber. The signal to noise ratio produced by the detector was about 100. The dosimeter system was tested at a category I gamma

  4. A NEW FRACTIONAL MODEL OF SINGLE DEGREE OF FREEDOM SYSTEM, BY USING GENERALIZED DIFFERENTIAL TRANSFORM METHOD

    Directory of Open Access Journals (Sweden)

    HASHEM SABERI NAJAFI

    2016-07-01

    Full Text Available Generalized differential transform method (GDTM is a powerful method to solve the fractional differential equations. In this paper, a new fractional model for systems with single degree of freedom (SDOF is presented, by using the GDTM. The advantage of this method compared with some other numerical methods has been shown. The analysis of new approximations, damping and acceleration of systems are also described. Finally, by reducing damping and analysis of the errors, in one of the fractional cases, we have shown that in addition to having a suitable solution for the displacement close to the exact one, the system enjoys acceleration once crossing the equilibrium point.

  5. High-dose rate fractionated interstitial radiotherapy for oropharyngeal carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Nose, Takayuki; Inoue, Toshihiko; Inoue, Takehiro; Teshima, Teruki; Murayama, Shigeyuki [Osaka Univ. (Japan). Faculty of Medicine

    1995-03-01

    The limitations of treating oropharyngeal cancer patients with definitive external radiotherapy are the complications of salivary glands, taste buds, mandible and temporomandibular joints. To avoid these complications we started interstitial radiotherapy as boost after 46 Gy of external radiotherapy. Ten cases (retromolar trigone; 1, soft palate; 1, base of tongue; 3, lateral wall; 5) were treated with this method and seven cases were controlled locally. With short follow-up period, xerostomia and dysgeusia are less than definitive external radiotherapy as clinical impression and no in-field recurrences have been experienced. With markedly increased tumor dose, the local control rate can be improved. This treatment method will be an alternative to definitive external radiotherapy to gain better QOL and higher control rate. (author).

  6. Australian high-dose-rate brachytherapy protocols for gynaecological malignancy

    International Nuclear Information System (INIS)

    MacLeod, C.; Dally, M.; Stevens, M.; Thornton, D.; Carruthers, S.; Jeal, P.

    2001-01-01

    There is no consensus over the optimal dose fractionation schedules for high-dose-rate (HDR) brachytherapy used for gynaecological malignancy. In Australian public hospital departments of radiation oncology, HDR brachytherapy for gynaecological cancer is being more commonly used. A survey of public departments that are using this technology, or that plan to introduce this technology, was performed. Their current protocols are presented. In general, protocols are similar biologically; however, the practical aspects such as the number of fractions given do vary and may reflect resource restrictions or, alternatively, differences in interpretations of the literature and of the best protocols by clinicians. Copyright (2001) Blackwell Science Pty Ltd

  7. Fractional single-phase-lagging heat conduction model for describing anomalous diffusion

    Directory of Open Access Journals (Sweden)

    T.N. Mishra

    2016-03-01

    Full Text Available The fractional single-phase-lagging (FSPL heat conduction model is obtained by combining scalar time fractional conservation equation to the single-phase-lagging (SPL heat conduction model. Based on the FSPL heat conduction model, anomalous diffusion within a finite thin film is investigated. The effect of different parameters on solution has been observed and studied the asymptotic behavior of the FSPL model. The analytical solution is obtained using Laplace transform method. The whole analysis is presented in dimensionless form. Numerical examples of particular interest have been studied and discussed in details.

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

    African Journals Online (AJOL)

    Concomitant chemoradiotherapy with high dose rate brachytherapy as a definitive treatment modality for locally advanced cervical cancer. T Refaat, A Elsaid, N Lotfy, K Kiel, W Small Jr, P Nickers, E Lartigau ...

  9. Fiber optics in high dose radiation fields

    International Nuclear Information System (INIS)

    Partin, J.K.

    1985-01-01

    A review of the behavior of state-of-the-art optical fiber waveguides in high dose (greater than or equal to 10 5 rad), steady state radiation fields is presented. The influence on radiation-induced transmission loss due to experimental parameters such as dose rate, total dose, irradiation history, temperature, wavelength, and light intensity, for future work in high dose environments are given

  10. Treatment outcome of high-dose image-guided intensity-modulated radiotherapy using intra-prostate fiducial markers for localized prostate cancer at a single institute in Japan

    International Nuclear Information System (INIS)

    Takeda, Ken; Shimizu, Eiji; Abe, Keiko; Shirata, Yuko; Ishikawa, Yohjiro

    2012-01-01

    Several studies have confirmed the advantages of delivering high doses of external beam radiotherapy to achieve optimal tumor-control outcomes in patients with localized prostate cancer. We evaluated the medium-term treatment outcome after high-dose, image-guided intensity-modulated radiotherapy (IMRT) using intra-prostate fiducial markers for clinically localized prostate cancer. In total, 141 patients with localized prostate cancer treated with image-guided IMRT (76 Gy in 13 patients and 80 Gy in 128 patients) between 2003 and 2008 were enrolled in this study. The patients were classified according to the National Comprehensive Cancer Network-defined risk groups. Thirty-six intermediate-risk patients and 105 high-risk patients were included. Androgen-deprivation therapy was performed in 124 patients (88%) for a median of 11 months (range: 2–88 months). Prostate-specific antigen (PSA) relapse was defined according to the Phoenix-definition (i.e., an absolute nadir plus 2 ng/ml dated at the call). The 5-year actuarial PSA relapse-free survival, the 5-year distant metastasis-free survival, the 5-year cause-specific survival (CSS), the 5-year overall survival (OS) outcomes and the acute and late toxicities were analyzed. The toxicity data were scored according to the Common Terminology Criteria for Adverse Events, version 4.0. The median follow-up was 60 months. The 5-year PSA relapse-free survival rates were 100% for the intermediate-risk patients and 82.2% for the high-risk patients; the 5-year actuarial distant metastasis-free survival rates were 100% and 95% for the intermediate- and high-risk patients, respectively; the 5-year CSS rates were 100% for both patient subsets; and the 5-year OS rates were 100% and 91.7% for the intermediate- and high-risk patients, respectively. The Gleason score (<8 vs. ≥8) was significant for the 5-year PSA relapse-free survival on multivariate analysis (p = 0.044). There was no grade 3 or 4 acute toxicity. The incidence of

  11. Characterization of a synthetic single crystal diamond detector for dosimetry in spatially fractionated synchrotron x-ray fields

    Energy Technology Data Exchange (ETDEWEB)

    Livingstone, Jayde, E-mail: Jayde.Livingstone@synchrotron.org.au; Häusermann, Daniel [Imaging and Medical Beamline, Australian Synchrotron, Clayton, Victoria 3168 (Australia); Stevenson, Andrew W. [Imaging and Medical Beamline, Australian Synchrotron, Clayton, Victoria 3168, Australia and CSIRO Manufacturing, Clayton South, Victoria 3169 (Australia); Butler, Duncan J. [Australian Radiation Protection and Nuclear Safety Agency, Yallambie, Victoria 3085 (Australia); Adam, Jean-François [Equipe d’accueil Rayonnement Synchrotron et Recherche Médicale, Université Grenoble Alpes, European Synchrotron Radiation Facility - ID17, Grenoble 38043, France and Centre Hospitalier Universitaire de Grenoble, Grenoble 38043 (France)

    2016-07-15

    Purpose: Modern radiotherapy modalities often use small or nonstandard fields to ensure highly localized and precise dose delivery, challenging conventional clinical dosimetry protocols. The emergence of preclinical spatially fractionated synchrotron radiotherapies with high dose-rate, sub-millimetric parallel kilovoltage x-ray beams, has pushed clinical dosimetry to its limit. A commercially available synthetic single crystal diamond detector designed for small field dosimetry has been characterized to assess its potential as a dosimeter for synchrotron microbeam and minibeam radiotherapy. Methods: Experiments were carried out using a synthetic diamond detector on the imaging and medical beamline (IMBL) at the Australian Synchrotron. The energy dependence of the detector was characterized by cross-referencing with a calibrated ionization chamber in monoenergetic beams in the energy range 30–120 keV. The dose-rate dependence was measured in the range 1–700 Gy/s. Dosimetric quantities were measured in filtered white beams, with a weighted mean energy of 95 keV, in broadbeam and spatially fractionated geometries, and compared to reference dosimeters. Results: The detector exhibits an energy dependence; however, beam quality correction factors (k{sub Q}) have been measured for energies in the range 30–120 keV. The k{sub Q} factor for the weighted mean energy of the IMBL radiotherapy spectrum, 95 keV, is 1.05 ± 0.09. The detector response is independent of dose-rate in the range 1–700 Gy/s. The percentage depth dose curves measured by the diamond detector were compared to ionization chambers and agreed to within 2%. Profile measurements of microbeam and minibeam arrays were performed. The beams are well resolved and the full width at halfmaximum agrees with the nominal width of the beams. The peak to valley dose ratio (PVDR) calculated from the profiles at various depths in water agrees within experimental error with PVDR calculations from Gafchromic film data

  12. Initial experience of single fraction radiotherapy (8 Gy x 1) in the treatment of painful bone metastases

    International Nuclear Information System (INIS)

    Amano, Kosuke; Ikeda, Hiroko; Chigusa, Satoshi; Tanaka, Masahiro; Katayama, Hirofumi; Takeda, Koji

    2014-01-01

    Sixteen patients with painful bone metastases received single fraction radiotherapy of 8 Gy. Single fraction radiotherapy was effective in providing pain relief with response rate of 88.8%. There were no severe acute side effects. The therapeutic regimen was also safe and effective in patients with poor performance status and poor prognosis. Therefore single fraction radiotherapy should be considered to treat pain arising from bone metastases. (author)

  13. Optimization of the temporal pattern of applied dose for a single fraction of radiation: Implications for radiation therapy

    Science.gov (United States)

    Altman, Michael B.

    given radiation pattern by concentrating the highest doses in the middle of a fraction (a "Triangle" pattern), or minimizing cell kill by placing the highest doses near the beginning and end (a "V-shaped" pattern). The conditions under which temporal optimization effects are most acute are also identified: irradiation of low alpha/beta tissues, long fraction durations, and high doses/fx. An in vitro study is then performed which verifies that the temporal effects and trends predicted by the modeling study are clearly manifested in human cells. Following this a phantom which could allow similar in vitro radiobiological experiments in a 3-dimensional clinically-based environment is designed, created, and dosimetrically assessed using TLDs, film, and biological assay-based techniques. The phantom is found to be a useful and versatile tool for such experiments. A scheme for utilizing the phantom in a clinical treatment environment is then developed. This includes a demonstration of prototype methods for optimizing the temporal pattern of applied dose in clinical IMRT plans to manipulate tissue-dependent effects. Looking toward future experimental validation of such plans using the phantom, an analysis of the suitability of biological assays for use in phantom-based in vitro experiments is performed. Finally, a discussion is provided about the steps necessary to integrate temporal optimization into in vivo experiments and ultimately into a clinical radiation therapy environment. If temporal optimization is ultimately shown to have impact in vivo, the successful implementation of the methods developed in this study could enhance the efficacy and care of thousands of patients receiving radiotherapy.

  14. Response of rat spinal cord to single and fractionated doses of accelerated heavy ions

    International Nuclear Information System (INIS)

    Leith, J.L.; McDonald, M.; Powers-Risius, P.; Bliven, S.F.; Walton, R.E.; Woodruff, K.H.; Howard, J.

    1980-01-01

    The response of rat spinal cord to irradiation with accelerated heavy ions, in particular carbon and neon ions has been studied. Two different ionization regions in the modified Bragg curve for each ion have been studied for both single and fractionated exposures. We have defined the paralytic response as a function of dose and dose per fraction, and we have determined RBE and repair values. The response of rat spinal cord is both dose and LET dependent, which allows the derivation of RBE and repair values

  15. Progress in high-dose radiation dosimetry

    International Nuclear Information System (INIS)

    Ettinger, K.V.; Nam, J.W.; McLaughlin, W.L.; Chadwick, K.H.

    1981-01-01

    The last decade has witnessed a deluge of new high-dose dosimetry techniques and expanded applications of methods developed earlier. Many of the principal systems are calibrated by means of calorimetry, although production of heat is not always the final radiation effect of interest. Reference systems also include a number of chemical dose meters: ferrous sulphate, ferrous-cupric sulphate, and ceric sulphate acidic aqueous solutions. Requirements for stable and reliable transfer dose meters have led to further developments of several important high-dose systems: amino acids and saccharides analysed by ESR or lyoluminescence, thermoluminescent materials, radiochromic dyes and plastics, ceric-cerous solutions analysed by potentiometry, and ethanol-chlorobenzene solutions analysed by high-frequency oscillometry. A number of other prospective dose meters are also treated in this review. In addition, an IAEA programme of high-dose standardization and intercomparison for industrial radiation processing is described. (author)

  16. Single isotope fractionation of (16)O(-) implications for early history of solar system

    Science.gov (United States)

    Arrhenius, G.

    1980-01-01

    Chemical fractionation processes are investigated with emphasis on selective single isotope fractionation in polyisotopic systems, particularly in oxygen. The related temperature parameters of meteoritic condensates and of their source medium are investigated by a thermometric method that is independent of assumptions regarding temperatures and pressures in the solar nebula. The crucial nonlinear chemical fractionation of O-16 was demonstrated experimentally. The effect was achieved in condensed CO2 formed from CO with C-12 O-16 selectively excited by H Ly alpha. The effect was verified by mass spectrometric measurements. The meteorite paleotemperature estimates were advanced from defining only thermal exposure to evaluating time and temperature independently. Grain temperatures at condensation of refractory inclusion materials are indicated to be less than 900 K in agreement with radiation temperature considerations and observations in circumstellar dust shells.

  17. Surface applicators for high dose rate brachytherapy in AIDS-related kaposi's sarcoma

    International Nuclear Information System (INIS)

    Evans, Michael D.C.; Yassa, Mariam; Podgorsak, Ervin B.; Roman, Ted N.; Schreiner, L. John; Souhami, Luis

    1997-01-01

    Purpose: The development of commercially available surface applicators using high dose rate remote afterloading devices has enabled radiotherapy centers to treat selected superficial lesions using a remote afterloading brachytherapy unit. The dosimetric parameters of these applicators, the clinical implementation of this technique, and a review of the initial patient treatment regimes are presented. Methods and Materials: A set of six fixed-diameter (1, 2, and 3 cm), tungsten/steel surface applicators is available for use with a single stepping-source (Ir-192, 370 GBq) high dose rate afterloader. The source can be positioned either in a parallel or perpendicular orientation to the treatment plane at the center of a conical aperture that sits at an SSD of approximately 15 mm and is used with a 1-mm thick removable plastic cap. The surface dose rates, percent depth dose, and off-axis ratios were measured. A custom-built, ceiling-mounted immobilization device secures the applicator on the surface of the patient's lesion during treatment. Results: Between November 1994, and September 1996, 16 AIDS-related Kaposi's sarcoma patients having a total of 120 lesions have been treated with palliative intent. Treatment sites were distributed between the head and neck, extremity, and torso. Doses ranged from 8 to 20 Gy, with a median dose of 10 Gy delivered in a single fraction. Treatments were well tolerated with minimal skin reaction, except for patients with lesions treated to 20 Gy who developed moderate/severe desquamation. Conclusion: Radiotherapy centers equipped with a high dose rate remote afterloading unit may treat small selected surface lesions with commercially available surface applicators. These surface applicators must be used with a protective cap to eliminate electron contamination. The optimal surface dose appears to be either 10 or 15 Gy depending upon the height of the lesion

  18. Prospective randomised multicenter trial on single fraction radiotherapy (8 Gyx1) versus multiple fractions (3 Gyx10) in the treatment of painful bone metastases

    International Nuclear Information System (INIS)

    Kaasa, Stein; Brenne, Elisabeth; Lund, Jo-Asmund; Fayers, Peter; Falkmer, Ursula; Holmberg, Matts; Lagerlund, Magnus; Bruland, Oivind

    2006-01-01

    Background and purpose: To investigate whether single-fraction radiotherapy is equal to multiple fractions in the treatment of painful metastases. Patients and methods: The study planned to recruit 1000 patients with painful bone metastases from four Norwegian and six Swedish hospitals. Patients were randomized to single-fraction (8 Gyx1) or multiple-fraction (3 Gyx10) radiotherapy. The primary endpoint of the study was pain relief, with fatigue and global quality of life as the secondary endpoints. Results: The data monitoring committee recommended closure of the study after 376 patients had been recruited because interim analyses indicated that, as in two other recently published trials, the treatment groups had similar outcomes. Both groups experienced similar pain relief within the first 4 months, and this was maintained throughout the 28-week follow-up. No differences were found for fatigue and global quality of life. Survival was similar in both groups, with median survival of 8-9 months. Conclusions: Single-fraction 8 Gy and multiple-fraction radiotherapy provide similar pain benefit. These results, confirming those of other studies, indicate that single-fraction 8 Gy should be standard management policy for these patients

  19. Gamma radiation-induced Impairment of hippocampal neurogenesis, comparison of single and fractionated dose regimens

    International Nuclear Information System (INIS)

    Khoshbin khoshnazar, A. R; Jahanshahi, M; Azami, N. S

    2012-01-01

    Radiation therapy of the brain is associated with many consequences, including cognitive disorders. Pathogenesis of radiation induced cognitive disorder is not clear, but reduction of neurogenesis in hippocampus may be an underlying reason. 24 adult male rats entered to study. Radiation absorbed dose to midbrain was 10 Gy, delivered by routine cobalt radiotherapy machine which its output was measured 115.24 cGy/min. The rats were divided in four groups of sixes, including groups of control, single fraction 10 Gy, fractionated 10 Gy and finally anaesthesia sham group. Number of pyramidal nerve cells was counted in two regions of hippocampus formation (CA1 and CA3). The radiation could reduce the number of cells in two regions of hippocampus significantly (p=0.000). It seems fractionated 10 Gy irradiation to more efficient than single fraction, while role of anaesthesia drug should be cautiously assessed. Moreover the rate of neurogenesis reduction was determined the same in these regions of hippocampus meaning the same radiosensitivity of cells

  20. Chromosome aberrations in human peripheral lymphocytes induced by single or fractionated X-irradiation

    International Nuclear Information System (INIS)

    Ivanov, B.; Leonard, A.; Deknyudt, G.

    1980-01-01

    Investigated is the effect of single (125 and 250 R) and fractionated (2x125 R) irradiation on the output of chromosome aberrations in lymphocytes of human peripheral blood kept between irradiations at the temperature of 5 deg C. The single irradiation is carried out immediately after vein-puncture. In the case of fractionated irradiation the first dose of 125R is given after vein-puncture, the second, in the interval of 2, 8 and 24 hours. Blood is cultivated immediately after two irradiations in order to prepare metaphase plates for cytogenic analysis. Repair processes in cell heritage structures are not realised in blood irradiated by fractions which is kept at 5 deg C between irradiations. On the contrary, chromosome fragments, interstitial deletions, aberrant cells and cell breaks are found in a large amount in blood irradiated by fractions. They have appeared with the authentically high statistic difference as compared with the cells irradiated one time with the same dose. This effect is probably attained due to blood preservation

  1. Optimal timing and frequency of bone marrow soup therapy for functional restoration of salivary glands injured by single-dose or fractionated irradiation.

    Science.gov (United States)

    Fang, Dongdong; Shang, Sixia; Liu, Younan; Bakkar, Mohammed; Sumita, Yoshinori; Seuntjens, Jan; Tran, Simon D

    2018-02-01

    Injections of bone marrow (BM) cell extract, known as 'BM soup', were previously reported to mitigate ionizing radiation (IR) injury to salivary glands (SGs). However, the optimal starting time and frequency to maintain BM soup therapeutic efficacy remains unknown. This study tested the optimal starting time and frequency of BM soup injections in mice radiated with either a single dose or a fractionated dose. First, BM soup treatment was started at 1, 3 or 7 weeks post-IR; positive (non-IR) and negative (IR) control mice received injections of saline (vehicle control). Second, BM soup-treated mice received injections at different frequencies (1, 2, 3 and 5 weekly injections). Third, a 'fractionated-dose radiation' model to injure mouse SGs was developed (5 Gy × 5 days) and compared with the single high dose radiation model. All mice (n = 65) were followed for 16 weeks post-IR. The results showed that starting injections of BM soup between 1 and 3 weeks mitigated the effect of IR-induced injury to SGs and improved the restoration of salivary function. Although the therapeutic effect of BM soup lessens after 8 weeks, it can be sustained by increasing the frequency of weekly injections. Moreover, both single-dose and fractionated-dose radiation models are efficient and comparable in inducing SG injury and BM soup treatments are effective in restoring salivary function in both radiation models. In conclusion, starting injections of BM soup within 3 weeks post-radiation, with 5 weekly injections, maintains 90-100% of saliva flow in radiated mice. Copyright © 2017 John Wiley & Sons, Ltd.

  2. Dose escalation by hypo fractionation in localized prostate cancer - a large single institution experience

    International Nuclear Information System (INIS)

    Mahadevan, A.; Klein, E.; Kupelian, P.

    2003-01-01

    To report the outcomes of high dose radiation therapy using Intensity Modulated Radiation Therapy (IMRT) with hypo fractionation in localized prostate cancer at the Cleveland Clinic Foundation. A total of 278 patients with localized prostate cancer were treated with IMRT between 1998 and 2001. All cases had available pretreatment PSA (iPSA) and biopsy Gleason scores (bGS), no nodal metastasis, a minimum 2 year follow-up, and >5 follow-up PSA levels. The frequency by T-stage was: T1-T2A in 86%, T2B-T2C in 9%, and T3 in 5%. The median iPSA was 8.35. The frequency by bGS was: =7 in 45%. The age range for the patients was from 48 to 85 years (median 68 years). The median follow-up was 33 months (range: 24-49 months). The median doses delivered were 83Gy (delivered at 2.5Gy per fraction to 70 Gy; this being equivalent to 83 Gy at standard fractionation of 1.8 Gy using an alpha/beta of 2). The ASTRO definition for biochemical failure was used. Toxicity was assessed using Radiation Therapy Oncology Group (RTOG) criteria. The 3-year biochemical relapse free survival (bRFS) for the entire cohort at three years was 91%. Any (grade 1 or higher) acute genito-urinary (GU) side effects were seen in 79% of patients. Grade 2 or higher acute GU toxicity was seen in 18% of patients. Any (grade 1 or higher) acute gastro-intestinal (GI) side effects were seen in 65% of patients. Grade 2 or higher acute GI toxicity was seen in 11% of patients. Any (grade 1 or higher) late GU side effects were seen in 3% of patients. Grade 2 or higher late GU toxicity was seen in 1.5% of patients. Any (grade 1 or higher) late GI side effects were seen in 13% of patients. Grade 2 or higher late GI toxicity was seen in 5% of patients. Higher doses of radiation delivered by IMRT resulted in excellent bRFS outcomes in patients with localized prostate cancer receiving external beam radiation therapy. IMRT can be effectively used to safely increase dose delivery without compromising on quality of life

  3. Pseudospectral operational matrix for numerical solution of single and multiterm time fractional diffusion equation

    OpenAIRE

    GHOLAMI, SAEID; BABOLIAN, ESMAIL; JAVIDI, MOHAMMAD

    2016-01-01

    This paper presents a new numerical approach to solve single and multiterm time fractional diffusion equations. In this work, the space dimension is discretized to the Gauss$-$Lobatto points. We use the normalized Grunwald approximation for the time dimension and a pseudospectral successive integration matrix for the space dimension. This approach shows that with fewer numbers of points, we can approximate the solution with more accuracy. Some examples with numerical results in tables and fig...

  4. Intracranial meningiomas after high-dose irradiation

    International Nuclear Information System (INIS)

    Soffer, D.; Gomori, J.M.; Siegal, T.; Shalit, M.N.

    1989-01-01

    Three patients who presented with intracranial meningiomas 12, 15, and 20 years, respectively, after therapeutic high-dose irradiation of a primary brain tumor are described. Analysis of these cases and similar documented cases suggests that meningiomas after high-dose irradiation constitute a recognizable entity. Patients with such tumors received radiation therapy at a young age (mean age, 9.4 years). After a latent period of 2 to 47 years (mean, 19.8 years) they developed meningiomas at the site of irradiation, at a much younger age than patients with ''spontaneous'' meningiomas. Similar to the situation with meningiomas after low-dose irradiation, a relatively high proportion of meningiomas induced by high-dose irradiation tend to be malignant and biologically aggressive. A very young age at the time of irradiation seems to predispose to the induction of malignant meningiomas, rather than benign tumors. These unusual features provide indirect evidence that high-dose radiation may play a role in the pathogenesis of meningiomas.41 references

  5. Endorectal high dose rate brachytherapy quality assurance

    International Nuclear Information System (INIS)

    Devic, S.; Vuong, T.; Evans, M.; Podgorsak, E.

    2008-01-01

    We describe our quality assurance method for preoperative high dose rate (HDR) brachytherapy of endorectal tumours. Reproduction of the treatment planning dose distribution on a daily basis is crucial for treatment success. Due to the cylindrical symmetry, two types of adjustments are necessary: applicator rotation and dose distribution shift along the applicator axis. (author)

  6. Impact of high-dose chemotherapy and autologous transplantation as first-line therapy on the survival of high-risk diffuse large B cell lymphoma patients: a single-center study in Japan.

    Science.gov (United States)

    Inano, Shojiro; Iwasaki, Makoto; Iwamoto, Yoshihiro; Sueki, Yuki; Fukunaga, Akiko; Yanagita, Soshi; Arima, Nobuyoshi

    2014-02-01

    High-dose chemotherapy (HDT), together with autologous stem cell transplantation (ASCT), plays an important role in the treatment of diffuse large B cell lymphoma (DLBCL), especially as second-line therapy. However, its significance in up-front settings remains to be elucidated. In our institute, patients with DLBCL in both the high-intermediate and high international prognostic index (IPI) groups initially underwent CHOP/R-CHOP treatment followed by HDT/ASCT at upfront settings between 2002 and 2011. We retrospectively analyzed 25 patients who were all treated with upfront HDT/ASCT. We excluded one patient who failed to undergo transplantation because of primary refractory disease from the analysis. The median follow-up was 77 months (range 17-110 months). Five-year overall survival (OS) and progression-free survival (PFS) were 91.7 and 79.2 %, respectively, which were higher than the equivalents in previous studies. The OS and PFS in the high-risk group were lower than those in the high-intermediate group. Treatment-related mortalities or fatal complication were not observed. Our results confirm that HDT/ASCT for high-risk aggressive lymphoma is a feasible and promising therapy, but patients with high IPI continued to have poor prognoses; improvements in treatment strategy are clearly needed. Since HDT/ASCT is an aggressive treatment option associated with long-term complications, we need to identify patient groups that will gain the maximum benefit from HDT/ASCT in the upfront setting.

  7. SU-F-T-02: Estimation of Radiobiological Doses (BED and EQD2) of Single Fraction Electronic Brachytherapy That Equivalent to I-125 Eye Plaque: By Using Linear-Quadratic and Universal Survival Curve Models

    International Nuclear Information System (INIS)

    Kim, Y; Waldron, T; Pennington, E

    2016-01-01

    Purpose: To test the radiobiological impact of hypofractionated choroidal melanoma brachytherapy, we calculated single fraction equivalent doses (SFED) of the tumor that equivalent to 85 Gy of I125-BT for 20 patients. Corresponding organs-at-risks (OARs) doses were estimated. Methods: Twenty patients treated with I125-BT were retrospectively examined. The tumor SFED values were calculated from tumor BED using a conventional linear-quadratic (L-Q) model and an universal survival curve (USC). The opposite retina (α/β = 2.58), macula (2.58), optic disc (1.75), and lens (1.2) were examined. The % doses of OARs over tumor doses were assumed to be the same as for a single fraction delivery. The OAR SFED values were converted into BED and equivalent dose in 2 Gy fraction (EQD2) by using both L-Q and USC models, then compared to I125-BT. Results: The USC-based BED and EQD2 doses of the macula, optic disc, and the lens were on average 118 ± 46% (p 14 Gy). Conclusion: The estimated single fraction doses were feasible to be delivered within 1 hour using a high dose rate source such as electronic brachytherapy (eBT). However, the estimated OAR doses using eBT were 112 ∼ 118% higher than when using the I125-BT technique. Continued exploration of alternative dose rate or fractionation schedules should be followed.

  8. Using the computed tomography in comparison to the orthogonal radiography based treatment planning in high dose rate (HDR) brachytherapy in cervical uteri cancer patients; a single institution feasibility study.

    Science.gov (United States)

    Bahadur, Yasir A; El-Sayed, Mohamed E; El-Taher, Zeinab H; Zaza, Khaled O; Moftah, Belal A; Hassouna, Ashraf H; Ghassal, Noor M

    2008-03-01

    Brachytherapy is an integral part in the treatment of cervical uteri cancer patients. Orthogonal treatment planning is the standard mode of calculation based on reference points. Introduction of the innovative 3-D computer based treatment planning allows accurate calculation based on volumetric information as regards the target volume and organs at risk (OAR). Also provide dose volume histogram (DVH) for proper estimation of the dose in relation to the volume. To correlate and compare the information obtained from the two approaches for high dose rate brachytherapy of cervical uteri cancer; the orthogonal conventional method and the computerized tomography (CT) three dimensions (3D) based calculation method in relation to the target and organ at risk (OAR). From 6 patients of cervical uteri cancer, 21 applications with orthogonal planning using the Brachy Vision treatment planning system version 7.3.10 were performed. In 10 applications; comparison between orthogonal and CT based planning was done. In orthogonal planning; the dose to point A, rectum and bladder were defined according to the American Brachytherapy Society (ABS) recommendation. From the CT based planning the target volume and dose volume histogram lpar;DVH) were calculated for the clinical target volume (CTV), rectum and bladder. From these two sets, information was obtained and compared and mean values were derived. For dose prescription at point A, an average of 63.5% of CTV received the prescribed dose. The mean ICRU dose to the bladder point is 2.9 Gy+/-1.2 SD (Standard Deviation) and 17% of the bladder volume derived from CT was encompassed by 2.9 Gy isodose line. The mean ICRU dose at the rectum point is 3.4 Gy+/-1.2 SD and 21% of the rectum volume from CT was encompassed by 3.4 Gy isodose line. The maximum dose to the rectum and the bladder derived from the CT and compared to the maximal dose at ICRU is 1.7 and 2.8 times higher than the orthogonal reference points; with the corresponding p

  9. Using the Computed Tomography in Comparison to the Orthogonal Radiography Based Treatment Planning in High dose Rate (HDR) Brachytherapy in Cervical Uteri Cancer Patients; A Single Institution Feasibility Study

    International Nuclear Information System (INIS)

    BAHADUR, Y.A.; EL-SAYED, M.E.; HASSOUNA, A.H.; EL-TAHER, Z.H.; GHASSAL, N.M.; ZAZA, Kh.O.M.D.; OFTAH, B.A.

    2008-01-01

    Brachytherapy is an integral part in the treatment of cervical uteri cancer patients. Orthogonal treatment planning is the standard mode of calculation based on reference points. Introduction of the innovative 3-D computer based treatment planning allows accurate calculation based on volumetric information as regards the target volume and organs at risk (OAR). Also provide dose volume histogram (DVH) for proper estimation of the dose in relation to the volume. Aim: To correlate and compare the information obtained from the two approaches for high dose rate brachytherapy of cervical uteri cancer; the orthogonal conventional method and the computerized tomography (CT) three dimensions (3D) based calculation method in relation to the target and organ at risk (OAR). Methods: From 6 patients of cervical uteri cancer, 21 applications with orthogonal planning using the Brachy Vision treatment planning system version 7.3.10 were performed. In 10 applications; comparison between orthogonal and CT based planning was done. In orthogonal planning; the dose to point A, rectum and bladder were defined according to the American Brachytherapy Society (ABS) recommendation. From the CT based planning the target volume and dose volume histogram (DVH) were calculated for the clinical target volume (CTV), rectum and bladder. From these two sets, information was obtained and compared and mean values were derived. Results: For dose prescription at point A, an average of 63.5% of CTV received the prescribed dose. The mean ICRU dose to the bladder point is 2.9 Gy±l .2 SD (Standard Deviation) and 17% of the bladder volume derived from CT was encompassed by 2.9 Gy isodose line. The mean ICRU dose at the rectum point is 3.4 Gy±1.2 SD and 21% of the rectum volume from CT was encompassed by 3.4 Gy isodose line. The maximum dose to the rectum and the bladder derived from the CT and compared to the maximal dose at ICRU is 1.7 and 2.8 times higher than the orthogonal reference points; with the

  10. Accelerated repopulation of mouse tongue epithelium during fractionated irradiations or following single doses

    International Nuclear Information System (INIS)

    Doerr, W.; Kummermehr, J.

    1990-01-01

    Mouse tongue mucosa was established as an animal model to study repopulation after large single doses or during continuous irradiation. A top-up irradiation technique was used employing priming doses or fractionated treatment to the whole snout (300 kV X-rays) followed by local test doses (25 kV X-rays) to elicit denudation in a confined field of the inferior tongue surface. Clearcut quantal dose-response curves of ulcer incidence were obtained to all protocols; animal morbidity, i.e. body weight loss was minimal. Repopulation following priming doses of 10 and 13 Gy started with a delay of at least 3 days and then progressed rapidly to nearly restore original tissue tolerance by day 11. During continuous fractionation over 1 to 3 weeks with 5 fractions/week and doses per fraction of 2.5, 3 and 3.5 Gy, repopulation was small in week one but subsequently increased to fully compensate the weekly dose at all dose levels. Additional measurements of cell density during a 4 weeks course of 5 x 3 Gy or 5 x 4 Gy per week showed only moderate depletion to 67% of the control figures. The fact that rapid repopulation is achieved at relatively moderate damage levels should be taken into account when the timing of a treatment split is considered. (author). 18 refs.; 7 figs.; 1 tab

  11. Single fraction prophylactic cranial irradiation for small cell carcinoma of the lung

    International Nuclear Information System (INIS)

    Brewster, A.E.; Hopwood, P.; Stout, R.; Burt, P.A.; Thatcher, N.

    1995-01-01

    The effectiveness of a single 8-Gy fraction prophylactic cranial irradiation regime was assessed in 106 patients with small-cell carcinoma of the lung. All patients had limited stage disease and received combination chemotherapy consisting of either cisplatin or carboplatin with ifosfamide, etoposide, and vincristine (VICE). Cranial irradiation was administered 48 h after the first cycle of chemotherapy and was well tolerated. Actual 2-year survival was 35% and cranial relapse occurred in 22% of those patients who achieved complete remission. This compares favourably with a cranial relapse rate of 45% incomplete remitters previously reported with the same chemotherapy regime after a minimum follow-up of 2 years where PCI was not used. Formal psychometric testing was performed retrospectively on a series of 25 long-term survivors of whom 14 were taken from this reported series. Whilst 75% of patients were impaired on at least one test with 68% performing badly in the most complex task, this was not associated with clinically detectable neurological damage and the patients did not complain of memory or concentration difficulties. In conclusion, single fraction PCI, when used with platinum based combination chemotherapy, appears to be equally effective but may be less neurotoxic than the more standard fractionated regimes

  12. Fractional Carbon Dioxide Laser for Keratosis Pilaris: A Single-Blind, Randomized, Comparative Study

    Directory of Open Access Journals (Sweden)

    Vasanop Vachiramon

    2016-01-01

    Full Text Available Objective. Keratosis pilaris (KP is a common condition which can frequently be cosmetically disturbing. Topical treatments can be used with limited efficacy. The objective of this study is to evaluate the effectiveness and safety of fractional carbon dioxide (CO2 laser for the treatment of KP. Patients and Methods. A prospective, randomized, single-blinded, intraindividual comparative study was conducted on adult patients with KP. A single session of fractional CO2 laser was performed to one side of arm whereas the contralateral side served as control. Patients were scheduled for follow-up at 4 and 12 weeks after treatment. Clinical improvement was graded subjectively by blinded dermatologists. Patients rated treatment satisfaction at the end of the study. Results. Twenty patients completed the study. All patients stated that the laser treatment improved KP lesions. At 12-week follow-up, 30% of lesions on the laser-treated side had moderate to good improvement according to physicians’ global assessment (p=0.02. Keratotic papules and hyperpigmentation appeared to respond better than the erythematous component. Four patients with Fitzpatrick skin type V developed transient pigmentary alteration. Conclusions. Fractional CO2 laser treatment may be offered to patients with KP. Dark-skinned patients should be treated with special caution.

  13. Functional and morphological changes in pig skin after single or fractionated doses in x rays

    International Nuclear Information System (INIS)

    Young, C.M.A.; Hopewell, J.W.

    1982-01-01

    The flank skin of pigs has been treated with either single or fractionated doses of x-irradiation. A single dose (2070 cGy) was compared with treatment given as 6 fractions in 18 days (6f/18 days; 3780 cGy) or 30 fractions in 39 days (30f/39 days; 8000 cGy). The doses were selected on the basis that similar levels of late tissue damage would result. Radiation induced changes in the skin were assessed by observing the skin reactions and by the measurement of isotope clearance (functional study), relative field contraction, dermal and epidermal thickness and dermal vascular density (morphological studies). In the three treatment groups the early radiation reaction varied considerably. In the first wave reaction (3 to 6 weeks after treatment) bright red erythema was recorded in many fields but moist desquamation developed only in the 30f/39 days treatment group. The second wave (10-16 weeks) was characterized by an ischemic mauve/dusky reaction. Dermal necrosis developed in 50% of the single dose fields. In the 30f/39 days regimen persistent moist desquamation progressed to dermal necrosis. Neither desquamation nor necrosis developed after 6f/18 days. Different levels of vascular damage in the dermis were assessed using an isotope clearance technique; for example in the early reaction significant changes were recorded in the papillary dermis (faster clearance) prior to the development of moist desquamation (30f/39 days) and in the reticular dermis (slower clearance) before necrosis (single dose). Changes in clearance rates have been correlated with changes in the vascular density and thickness of the dermis. Between 26 and 52 weeks (the late reaction) relative field contraction was slightly greater in the 30f/39 days group than in the other treatment groups

  14. High-dose mode of mortality in Tribolium: A model system for study of radiation injury and repair in non-proliferative tissues

    International Nuclear Information System (INIS)

    Cheng, Chihing Christina.

    1989-01-01

    With appropriate doses of ionizing radiation, both the acute, or lethal-midlethal, dose-independent pattern of mortality, and the hyperacute, dose-dependent pattern, were demonstrated within a single insect genus (Tribolium). This demonstration provides resolution of apparently contradictory reports of insect radiation responses in terms of doses required to cause lethality and those based on survival time as a function of dose. A dose-dependent mortality pattern was elicited in adult Tribolium receiving high doses, viz., 300 Gy or greater; its time course was complete in 10 days, before the dose-independent pattern of mortality began. Visual observations of heavily-irradiated Tribolium suggested neural and/or neuromuscular damage, as had been previously proposed by others for lethally-irradiated wasps, flies, and mosquitoes. Results of experiments using fractionated high doses supported the suggestion that the hyperacute or high-dose mode of death is the result of damage to nonproliferative tissues. Relative resistance of a strain to the hyperacute or high-dose mode of death was not correlated with resistance to the midlethal mode, which is believed to be the result of damage to the proliferative cells of the midgut. Using the high-dose mode of death as a model of radiation damage to nonproliferative tissues, the effects of age, and of a moderate priming dose were assessed. Beetles showed age-related increase in sensitivity to the high-dose mode of death, suggesting a decline in capacity to repair radiation damage to postmitotic tissue. This correlated with a decrease (50%) in the amount of repair reflected in the sparing effect of dose-fractionation (SDF) between the age of 1 to 3 months. The age related increase in radiosensitivity was reduced by a moderate priming dose (40 or 65 Gy) given at a young age

  15. High-dose irradiation of food

    International Nuclear Information System (INIS)

    Diehl, J.F.

    1999-01-01

    Studies performed on behalf of the International Project on Food Irradiation in the period from 1971 until 1980 resulted in the concluding statement that ''.the irradiation of any food commodity up to an overall average dose of 10 kGy presents no toxicological hazard; hence, toxicological testing of foods so treated is no longer required.'' Since then, licenses for food irradiation have been restricted to this maximum dose in any country applying this technology. Further testing programmes have been carried out investigating the wholesomeness or hazards of high-dose irradiation, but there has been little demand so far by the food industry for licensing of high-dose irradiation, as there is only a small range of products whose irradiation at higher doses offers advantages for given, intended use. These include eg. spices, dried herbs, meat products in flexible pouch packagings for astronauts, or patients with immune deficiencies. (orig./CB) [de

  16. High-dose erythropoietin for tissue protection

    DEFF Research Database (Denmark)

    Lund, Anton; Lundby, Carsten; Olsen, Niels Vidiendal

    2014-01-01

    BACKGROUND: The discovery of potential anti-apoptotic and cytoprotective effects of recombinant human erythropoietin (rHuEPO) has led to clinical trials investigating the use of high-dose, short-term rHuEPO therapy for tissue protection in conditions such as stroke and myocardial infarction....... Experimental studies have been favourable, but the clinical efficacy has yet to be validated. MATERIALS AND METHODS: We have reviewed clinical studies regarding the use of high-dose, short-term rHuEPO therapy for tissue protection in humans with the purpose to detail the safety and efficacy of r...... no effect of rHuEPO therapy on measures of tissue protection. Five trials including 1025 patients reported safety concerns in the form of increased mortality or adverse event rates. No studies reported reduced mortality. CONCLUSIONS: Evidence is sparse to support a tissue-protective benefit of r...

  17. Copenhagen's single system premise prevents a unified view of integer and fractional quantum hall effect

    Science.gov (United States)

    Post, Evert Jan

    1999-05-01

    This essay presents conclusive evidence of the impermissibility of Copenhagen's single system interpretation of the Schroedinger process. The latter needs to be viewed as a tool exclusively describing phase and orientation randomized ensembles and is not be used for isolated single systems. Asymptotic closeness of single system and ensemble behavior and the rare nature of true single system manifestations have prevented a definitive identification of this Copenhagen deficiency over the past three quarter century. Quantum uncertainty so becomes a basic trade mark of phase and orientation disordered ensembles. The ensuing void of usable single system tools opens a new inquiry for tools without statistical connotations. Three, in part already known, period integrals here identified as flux, charge and action counters emerge as diffeo-4 invariant tools fully compatible with the demands of the general theory of relativity. The discovery of the quantum Hall effect has been instrumental in forcing a distinction between ensemble disorder as in the normal Hall effect versus ensemble order in the plateau states. Since the order of the latter permits a view of the plateau states as a macro- or meso-scopic single system, the period integral description applies, yielding a straightforward unified description of integer and fractional quantum Hall effects.

  18. Single-dose and fractionated irradiation of four human lung cancer cell lines in vitro

    International Nuclear Information System (INIS)

    Brodin, O.; Lennartsson, L.; Nilsson, S.

    1991-01-01

    Four established human lung cancer cell lines were exposed to single-dose irradiation. The survival curves of 2 small cell lung carcinomas (SCLC) were characterized by a limited capacity for repair with small and moderate shoulders with extrapolation numbers (n) of 1.05 and 1.60 respectively. Two non-small cell lung carcinoma (NSCLC) cell lines, one squamous cell (SQCLC) and one large cell (LCLC) had large shoulders with n-values of 73 and 15 respectively. The radiosensitivity when measured as D 0 did not, however, differ as much from cell line to cell line, with values from 1.22 to 1.65. The surviving fraction after 2 Gy (SF2) was 0.24 and 0.42 respectively in the SCLC cell lines and 0.90 and 0.88 respectively in the NSCLC cell lines. Fractionated irradiation delivered according to 3 different schedules was also investigated. All the schedules delivered a total dose of 10 Gy in 5 days and were applied in 1, 2 and 5 Gy dose fractions respectively. Survival followed the pattern found after single-dose irradiation; it was lowest in the SCLC cell line with the lowest SF and highest in the two NSCLC cell lines. In the SCLC cell lines all schedules were approximately equally efficient. In the LCLC and in the SQCLC cell lines, the 5 Gy schedule killed more cells than the 1 and 2 Gy schedules. The results indicate that the size of the shoulder of the survival curve is essential when choosing the most tumoricidal fractionation schedule. (orig.)

  19. Physics and quality assurance for high dose rate brachytherapy

    International Nuclear Information System (INIS)

    Anderson, Lowell L.

    1995-01-01

    Purpose: To review the physical aspects of high dose rate (HDR) brachytherapy, including commissioning and quality assurance, source calibration and dose distribution measurements, and treatment planning methods. Following the introduction of afterloading in brachytherapy, development efforts to make it 'remote' culminated in 1964 with the near-simultaneous appearance of remote afterloaders in five major medical centers. Four of these machines were 'high dose rate', three employing 60Co and one (the GammaMed) using a single, cable-mounted 192Ir source. Stepping-motor source control was added to the GammaMed in 1974, making it the precursor of modern remote afterloaders, which are now suitable for interstitial as well as intracavitary brachytherapy by virtue of small source-diameter and indexer-accessed multiple channels. Because the 192Ir sources currently used in HDR remote afterloaders are supplied at a nominal air-kerma strength of 11.4 cGy cm2 s-1 (10 Ci), are not collimated in clinical use, and emit a significant fraction (15%) of photons at energies greater than 600 keV, shielding and facility design must be undertaken as carefully and thoroughly as for external beam installations. Licensing requirements of regulatory agencies must be met with respect both to maximum permissible dose limits and to the existence and functionality of safety devices (door interlocks, radiation monitors, etc.). Commissioning and quality assurance procedures that must be documented for HDR remote afterloading relate to (1) machine, applicator, guide-tube, and facility functionality checks, (2) source calibration, (3) emergency response readiness, (4) planning software evaluation, and (5) independent checks of clinical dose calculations. Source calibration checks must be performed locally, either by in-air measurement of air kerma strength or with a well ionization chamber calibrated (by an accredited standards laboratory) against an in-air measurement of air kerma strength for the

  20. Single vs. multiple fraction regimens for palliative radiotherapy treatment of multiple myeloma. A prospective randomised study

    International Nuclear Information System (INIS)

    Rudzianskiene, Milda; Inciura, Arturas; Gerbutavicius, Rolandas; Rudzianskas, Viktoras; Dambrauskiene, Ruta; Juozaityte, Elona; Macas, Andrius; Simoliuniene, Renata; Kiavialaitis, Greta Emilia

    2017-01-01

    To compare the impact of a single fraction (8 Gy x 1 fraction) and multifraction (3 Gy x 10 fractions) radiotherapy regimens on pain relief, recalcification and the quality of life (QoL) in patients with bone destructions due to multiple myeloma (MM). In all, 101 patients were included in a randomised prospective clinical trial: 58 patients were included in the control arm (3 Gy x 10 fractions) and 43 patients into the experimental arm (8 Gy x 1 fraction). The response rate was defined according to the International Consensus on Palliative Radiotherapy criteria. Recalcification was evaluated with radiographs. QoL questionnaires were completed before and 4 weeks after treatment. Pain relief was obtained in 81/101 patients (80.2%): complete response in 56 (69%) and partial in 25 patients (30.9%). No significant differences were observed in analgesic response between the groups. Significant factors for pain relief were female gender, age under 65, IgG MM type, presence of recalcification at the irradiated site. Recalcification was found in 32/101 patients (33.7%): complete in 17 (53.2%) and partial in 15 (46.2%). No significant differences were observed in recalcification between the groups. Significant factors for recalcification were Karnofsky index ≥ 60%, haemoglobin level ≤ 80 g/dl, MM stage II and analgesic response at the irradiated site. The QoL after radiotherapy was improved in the control group. The same analgesic and recalcification response was observed using two different radiotherapy regimens. Higher doses should be used to achieve a better QoL. (orig.) [de

  1. Postoperative Single-Fraction Radiation for Prevention of Heterotopic Ossification of the Elbow

    International Nuclear Information System (INIS)

    Robinson, Clifford G.; Polster, Joshua M.; Reddy, Chandana A.; Lyons, Janice A.; Evans, Peter J.; Lawton, Jeffrey N.; Graham, Thomas J.; Suh, John H.

    2010-01-01

    Purpose: Heterotopic ossification (HO) about the elbow has been described after surgery, trauma, and burns. Even limited deposits can lead to significant functional deficits. Little data exist regarding outcomes of patients treated with radiation therapy (RT) after elbow surgery. We report here the Cleveland Clinic experience with single-fraction radiation following surgery to the elbow. The primary endpoint was the rate of new HO after RT. Secondary endpoints were range of motion, functional compromise, and toxicity. Methods and Materials: From May 1993 to July 2006, 36 patients underwent elbow surgery followed by single-fraction RT. Range of motion data were collected before and during surgery and at last follow-up. Radiographs were reviewed for persistent or new HO. Patient and treatment factors were analyzed for correlation with development of HO or functional compromise. Results: Median follow-up was 8.7 months, median age was 42 years, and 75% of patients were male. Twenty-six (72%) patients had HO prior to surgery. All patients had significant limitations in flexion/extension or pronation/supination at baseline. Thirty-one (86%) patients had prior elbow trauma, and 26 (72%) patients had prior surgery. RT was administered a median of 1 day postoperatively (range, 1-4 days). Thirty-four patients received 700 cGy, and 2 patients received 600 cGy. Three (8%) patients developed new HO after RT. All patients had improvement in range of motion from baseline. No patient or treatment factors were significantly associated with the development of HO or functional compromise. Conclusions: Single-fraction RT after surgery to the elbow is associated with favorable functional and radiographic outcomes.

  2. The effects of single and fractionated irradiation of the trunk in rats

    International Nuclear Information System (INIS)

    Giri, P.G.S.; Kimler, B.F.; Giri, U.P.; Cox, G.G.; Reddy, E.K.

    1985-01-01

    The effect of whole trunk irradiation on the development of functional damage was investigated in rats. Rats were restrained without anesthesia such that only the trunk (from clavicle to pelvic girdle) was irradiated with a Cs-137 irradiator at a dose rate of 8.5 Gy/min. Rats received single doses of 9.4, 11.7, 14.1, or 16.4 Gy; or total doses of 11.7, 14.1, 16.4, 18.8, or 21.1 Gy in two equal fractions separated by 4-6 hr. Except for the highest dose in both schedules, there was no lethality; 16.4 Gy reduced survival to 45% and 21.1 Gy in two fractions reduced survival to 77% by day 150. From day 10 to day 150 there was a dose-dependent reduction in weight for both schedules, with the two-dose response displaced from the single dose response by ≅ 6 Gy. A whole-body plethysmograph was used to measure respiration frequency. There was no increase in respiration frequency compared to control animals, except for the highest single dose - 16.4 Gy producing an increase that was manifested from 10 to 150 days. The authors conclude that, in this rat trunk irradiation model, fractionation into two equal doses separated by 4-6 hr produces a sparing effect of ≅ 6 Gy as measured by delay in weight gain (presumably a result of irradiation of the abdomen); and ≥ 6 Gy as measured by survival and increased respiration frequency (a result of irradiation of the thorax)

  3. Long-term Evaluation of Radiation-Induced Optic Neuropathy After Single-Fraction Stereotactic Radiosurgery

    International Nuclear Information System (INIS)

    Leavitt, Jacqueline A.; Stafford, Scott L.; Link, Michael J.; Pollock, Bruce E.

    2013-01-01

    Purpose: To determine the long-term risk of radiation-induced optic neuropathy (RION) in patients having single-fraction stereotactic radiosurgery (SRS) for benign skull base tumors. Methods and Materials: Retrospective review of 222 patients having Gamma Knife radiosurgery for benign tumors adjacent to the anterior visual pathway (AVP) between 1991 and 1999. Excluded were patients with prior or concurrent external beam radiation therapy or SRS. One hundred twenty-nine patients (58%) had undergone previous surgery. Tumor types included confirmed World Health Organization grade 1 or presumed cavernous sinus meningioma (n=143), pituitary adenoma (n=72), and craniopharyngioma (n=7). The maximum dose to the AVP was ≤8.0 Gy (n=126), 8.1-10.0 Gy (n=39), 10.1-12.0 Gy (n=47), and >12 Gy (n=10). Results: The mean clinical and imaging follow-up periods were 83 and 123 months, respectively. One patient (0.5%) who received a maximum radiation dose of 12.8 Gy to the AVP developed unilateral blindness 18 months after SRS. The chance of RION according to the maximum radiation dose received by the AVP was 0 (95% confidence interval [CI] 0-3.6%), 0 (95% CI 0-10.7%), 0 (95% CI 0-9.0%), and 10% (95% CI 0-43.0%) for patients receiving ≤8 Gy, 8.1-10.0 Gy, 10.1-12.0 Gy, and >12 Gy, respectively. The overall risk of RION in patients receiving >8 Gy to the AVP was 1.0% (95% CI 0-6.2%). Conclusions: The risk of RION after single-fraction SRS in patients with benign skull base tumors who have no prior radiation exposure is very low if the maximum dose to the AVP is ≤12 Gy. Physicians performing single-fraction SRS should remain cautious when treating lesions adjacent to the AVP, especially when the maximum dose exceeds 10 Gy

  4. Long-term Evaluation of Radiation-Induced Optic Neuropathy After Single-Fraction Stereotactic Radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Leavitt, Jacqueline A., E-mail: leavitt.jacqueline@mayo.edu [Department of Ophthalmology, Mayo Clinic and Foundation, Rochester, Minnesota (United States); Stafford, Scott L. [Department of Radiation Oncology, Mayo Clinic and Foundation, Rochester, Minnesota (United States); Link, Michael J. [Department of Neurosurgery, Mayo Clinic and Foundation, Rochester, Minnesota (United States); Pollock, Bruce E. [Department of Radiation Oncology, Mayo Clinic and Foundation, Rochester, Minnesota (United States); Department of Neurosurgery, Mayo Clinic and Foundation, Rochester, Minnesota (United States)

    2013-11-01

    Purpose: To determine the long-term risk of radiation-induced optic neuropathy (RION) in patients having single-fraction stereotactic radiosurgery (SRS) for benign skull base tumors. Methods and Materials: Retrospective review of 222 patients having Gamma Knife radiosurgery for benign tumors adjacent to the anterior visual pathway (AVP) between 1991 and 1999. Excluded were patients with prior or concurrent external beam radiation therapy or SRS. One hundred twenty-nine patients (58%) had undergone previous surgery. Tumor types included confirmed World Health Organization grade 1 or presumed cavernous sinus meningioma (n=143), pituitary adenoma (n=72), and craniopharyngioma (n=7). The maximum dose to the AVP was ≤8.0 Gy (n=126), 8.1-10.0 Gy (n=39), 10.1-12.0 Gy (n=47), and >12 Gy (n=10). Results: The mean clinical and imaging follow-up periods were 83 and 123 months, respectively. One patient (0.5%) who received a maximum radiation dose of 12.8 Gy to the AVP developed unilateral blindness 18 months after SRS. The chance of RION according to the maximum radiation dose received by the AVP was 0 (95% confidence interval [CI] 0-3.6%), 0 (95% CI 0-10.7%), 0 (95% CI 0-9.0%), and 10% (95% CI 0-43.0%) for patients receiving ≤8 Gy, 8.1-10.0 Gy, 10.1-12.0 Gy, and >12 Gy, respectively. The overall risk of RION in patients receiving >8 Gy to the AVP was 1.0% (95% CI 0-6.2%). Conclusions: The risk of RION after single-fraction SRS in patients with benign skull base tumors who have no prior radiation exposure is very low if the maximum dose to the AVP is ≤12 Gy. Physicians performing single-fraction SRS should remain cautious when treating lesions adjacent to the AVP, especially when the maximum dose exceeds 10 Gy.

  5. Mortality following single-fraction stereotactic body radiation therapy for central pulmonary oligometastasis.

    Science.gov (United States)

    Ma, Sung Jun; Mix, Michael; Rivers, Charlotte; Hennon, Mark; Gomez, Jorge; Singh, Anurag K

    2017-01-01

    The case of a 56-year-old male who developed bronchopulmonary hemorrhage after a course of stereotactic body radiation therapy (SBRT) for centrally located squamous cell lung carcinoma is presented. The patient was previously treated with concurrent chemoradiation for stage IVA squamous cell carcinoma of the base of tongue. He showed no evidence of disease for 4 years until he developed a solitary metastasis of squamous cell carcinoma in the right hilum. He underwent a single fraction of 26 Gy with heterogeneity correction. He showed no evidence of disease for 13 months until he developed a sudden grade 4 bronchopulmonary hemorrhage. He underwent an urgent right pneumonectomy and later died of a post-operative complication. Pathologic analysis of the specimen revealed no evidence of tumor. Single-fraction SBRT of 26 Gy was sufficient to achieve complete response of his large central lung tumor. However, when treating patients with central lung tumors, some risk of mortality may be unavoidable with either SBRT or pneumonectomy.

  6. Benefits of online in vivo dosimetry for single-fraction total body irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Eaton, David J., E-mail: davideaton@nhs.net [Department of Radiotherapy, Royal Free Hospital, London (United Kingdom); Warry, Alison J. [Department of Radiotherapy Physics, University College London Hospital, London (United Kingdom); Trimble, Rachel E.; Vilarino-Varela, Maria J.; Collis, Christopher H. [Department of Radiotherapy, Royal Free Hospital, London (United Kingdom)

    2014-01-01

    Use of a patient test dose before single-fraction total body irradiation (TBI) allows review of in vivo dosimetry and modification of the main treatment setup. However, use of computed tomography (CT) planning and online in vivo dosimetry may reduce the need for this additional step. Patients were treated using a supine CT-planned extended source-to-surface distance (SSD) technique with lead compensators and bolus. In vivo dosimetry was performed using thermoluminescent dosimeters (TLDs) and diodes at 10 representative anatomical locations, for both a 0.1-Gy test dose and the treatment dose. In total, 28 patients were treated between April 2007 and July 2013, with changes made in 10 cases (36%) following test dose results. Overall, 98.1% of measured in vivo treatment doses were within 10% of the prescribed dose, compared with 97.0% of test dose readings. Changes made following the test dose could have been applied during the single-fraction treatment itself, assuming that the dose was delivered in subportions and online in vivo dosimetry was available for all clinically important anatomical sites. This alleviates the need for a test dose, saving considerable time and resources.

  7. Benefits of online in vivo dosimetry for single-fraction total body irradiation

    International Nuclear Information System (INIS)

    Eaton, David J.; Warry, Alison J.; Trimble, Rachel E.; Vilarino-Varela, Maria J.; Collis, Christopher H.

    2014-01-01

    Use of a patient test dose before single-fraction total body irradiation (TBI) allows review of in vivo dosimetry and modification of the main treatment setup. However, use of computed tomography (CT) planning and online in vivo dosimetry may reduce the need for this additional step. Patients were treated using a supine CT-planned extended source-to-surface distance (SSD) technique with lead compensators and bolus. In vivo dosimetry was performed using thermoluminescent dosimeters (TLDs) and diodes at 10 representative anatomical locations, for both a 0.1-Gy test dose and the treatment dose. In total, 28 patients were treated between April 2007 and July 2013, with changes made in 10 cases (36%) following test dose results. Overall, 98.1% of measured in vivo treatment doses were within 10% of the prescribed dose, compared with 97.0% of test dose readings. Changes made following the test dose could have been applied during the single-fraction treatment itself, assuming that the dose was delivered in subportions and online in vivo dosimetry was available for all clinically important anatomical sites. This alleviates the need for a test dose, saving considerable time and resources

  8. Gemcitabine Chemotherapy and Single-Fraction Stereotactic Body Radiotherapy for Locally Advanced Pancreatic Cancer

    International Nuclear Information System (INIS)

    Schellenberg, Devin; Goodman, Karyn A.; Lee, Florence; Chang, Stephanie; Kuo, Timothy; Ford, James M.; Fisher, George A.; Quon, Andrew; Desser, Terry S.; Norton, Jeffrey; Greco, Ralph; Yang, George P.; Koong, Albert C.

    2008-01-01

    Purpose: Fractionated radiotherapy and chemotherapy for locally advanced pancreatic cancer achieves only modest local control. This prospective trial evaluated the efficacy of a single fraction of 25 Gy stereotactic body radiotherapy (SBRT) delivered between Cycle 1 and 2 of gemcitabine chemotherapy. Methods and Materials: A total of 16 patients with locally advanced, nonmetastatic, pancreatic adenocarcinoma received gemcitabine with SBRT delivered 2 weeks after completion of the first cycle. Gemcitabine was resumed 2 weeks after SBRT and was continued until progression or dose-limiting toxicity. The gross tumor volume, with a 2-3-mm margin, was treated in a single 25-Gy fraction by Cyberknife. Patients were evaluated at 4-6 weeks, 10-12 weeks, and every 3 months after SBRT. Results: All 16 patients completed SBRT. A median of four cycles (range one to nine) of chemotherapy was delivered. Three patients (19%) developed local disease progression at 14, 16, and 21 months after SBRT. The median survival was 11.4 months, with 50% of patients alive at 1 year. Patients with normal carbohydrate antigen (CA)19-9 levels either at diagnosis or after Cyberknife SBRT had longer survival (p <0.01). Acute gastrointestinal toxicity was mild, with 2 cases of Grade 2 (13%) and 1 of Grade 3 (6%) toxicity. Late gastrointestinal toxicity was more common, with five ulcers (Grade 2), one duodenal stenosis (Grade 3), and one duodenal perforation (Grade 4). A trend toward increased duodenal volumes radiated was observed in those experiencing late effects (p = 0.13). Conclusion: SBRT with gemcitabine resulted in comparable survival to conventional chemoradiotherapy and good local control. However, the rate of duodenal ulcer development was significant

  9. High dose rate endobronchial brachytherapy - treatment technique

    International Nuclear Information System (INIS)

    Carvalho, Heloisa de Andrade; Aisen, Salim; Haddad, Cecilia Maria Kalil; Nadalin, Wladimir; Pedreira Junior, Wilson Leite; Chavantes, Maria Cristina

    1998-01-01

    High dose rate endobronchial brachytherapy is efficient in symptom relief due to obstructive endobronchial malignancies. However, it's role in survival improvement for patients with lung cancer is not yet established. The use of this treatment in increasing, specially in the developing countries. The purpose of this paper is to present the treatment technique used in the Radiotherapy Department of the Hospital da Clinicas, University of Sao Paulo, based on an experience of 60 cases treated with 180 procedures. Some practical suggestions and rules adopted in the Department are described. The severe complications rate is 6.7%, demonstrating an adequate patient selection associated with the technique utilized. (author)

  10. Neuroprotective potential of high-dose biotin.

    Science.gov (United States)

    McCarty, Mark F; DiNicolantonio, James J

    2017-11-01

    A recent controlled trial has established that high-dose biotin supplementation - 100 mg, three times daily - has a stabilizing effect on progression of multiple sclerosis (MS). Although this effect has been attributed to an optimization of biotin's essential cofactor role in the brain, a case can be made that direct stimulation of soluble guanylate cyclase (sGC) by pharmacological concentrations of biotin plays a key role in this regard. The utility of high-dose biotin in MS might reflect an anti-inflammatory effect of cGMP on the cerebral microvasculature, as well on oligodendrocyte differentiation and on Schwann cell production of neurotrophic factors thought to have potential for managing MS. But biotin's ability to boost cGMP synthesis in the brain may have broader neuroprotective potential. In many types of neurons and neural cells, cGMP exerts neurotrophic-mimetic effects - entailing activation of the PI3K-Akt and Ras-ERK pathways - that promote neuron survival and plasticity. Hippocampal long term potentiation requires nitric oxide synthesis, which in turn promotes an activating phosphorylation of CREB via a pathway involving cGMP and protein kinase G (PKG). In Alzheimer's disease (AD), amyloid beta suppresses this mechanism by inhibiting sGC activity; agents which exert a countervailing effect by boosting cGMP levels tend to restore effective long-term potentiation in rodent models of AD. Moreover, NO/cGMP suppresses amyloid beta production within the brain by inhibiting expression of amyloid precursor protein and BACE1. In conjunction with cGMP's ability to oppose neuron apoptosis, these effects suggest that high-dose biotin might have potential for the prevention and management of AD. cGMP also promotes neurogenesis, and may lessen stroke risk by impeding atherogenesis and hypertrophic remodeling in the cerebral vasculature. The neuroprotective potential of high-dose biotin likely could be boosted by concurrent administration of brain

  11. Comparison of single, fractionated and hyperfractionated irradiation on the development of normal tissue damage in rat lung

    International Nuclear Information System (INIS)

    Giri, P.G.S.; Kimler, B.F.; Giri, U.P.; Cox, G.G.; Reddy, E.K.

    1985-01-01

    The effect of fractionated thoracic irradiation on the development of normal tissue damage in rats was compared to that produced by single doses. Animals received a single dose of 15 Gy, 30 Gy in 10 daily fractions of 3 Gy each (fractionation), or 30 Gy in 30 fractions of 1 Gy each 3 times a day (hyperfractionation). The treatments produced minimal lethality since a total of only 6 animals died between days 273 and 475 after the initiation of treatment, with no difference in survival observed between the control and any of the 3 treated groups. Despite the lack of lethality, evidence of lung damage was obtained by histological examination. Animals that had received either single doses or fractionated doses had more of the pulmonary parenchyma involved than did animals that had received hyperfractionated doses. The authors conclude that, in the rat lung model, a total radiation dose of 30 Gy fractionated over 14 days produces no more lethality nor damage to lung tissue than does 15 Gy delivered as a single dose. However, long-term effects as evidenced by deposits of collagen and development of fibrosis are significantly reduced by hyperfractionation when compared to single doses and daily fractionation

  12. Transperineal high-dose-rate interstitial radiation therapy in the management of gynecologic malignancies

    Energy Technology Data Exchange (ETDEWEB)

    Itami, Jun; Hara, Ryuseke; Kozuka, Takuyou; Yamashita, Hideomi; Nakajima, Kaori; Shibata, Kouji; Abe, Yoshihisa; Fuse, Masashi; Ito, Masashi [International Medical Center of Japan, Tokyo (Japan). Dept. of Radiation Therapy and Oncology

    2003-11-01

    Background: High-dose-rate interstitial radiation therapy is a newly introduced modality, and its role in the management of gynecologic malignancies remains to be studied. Clinical experience in high-dose-rate interstitial radiation therapy was retrospectively investigated. Patients and Methods: Eight patients with primary and nine with recurrent gynecologic malignancies underwent high-dose-rate interstitial radiation therapy with/without external-beam irradiation. Fractional dose of the high-dose-rate interstitial radiation therapy ranged between 4 and 6 Gy with total doses of 15-54 Gy. Interstitial irradiation was performed twice daily with an interval of > 6 h. Results: 2-year local control rate was 75% for primary treatment and 47% for treatment of recurrence (p = 0.46). Maximum tumor size had a statistically significant impact on local control (p < 0.002). Grade 2 and 4 late complications were seen in five patients, and the incidence was significantly higher in patients with a larger volume enclosed by the prescribed fractional dose of high-dose-rate interstitial radiation therapy. The incidence of grade 2 and 4 complications at 18 months was 78% and 0% with a volume > 100 cm{sup 3} and {<=} 100 cm{sup 3}, respectively (p < 0.04). Conclusion: Although high-dose-rate interstitial radiation therapy is a promising modality, it must be applied cautiously to patients with bulky tumors because of the high incidence of serious complications. (orig.)

  13. Immune reactivity after high-dose irradiation

    International Nuclear Information System (INIS)

    Gassmann, W.; Wottge, H.U.; von Kolzynski, M.; Mueller-Ruchholtz, W.

    1986-01-01

    Immune reactivity after total-body irradiation was investigated in rats using skin graft rejection as the indicator system. After sublethal irradiation with 10.5 Gy (approximately 50% lethality/6 weeks) the rejection of major histocompatibility complex allogeneic skin grafts was delayed significantly compared with nonirradiated control animals (28 versus 6.5 days). In contrast, skin grafts were rejected after 7.5 days in sublethally irradiated animals and 7 days in lethally irradiated animals if additional skin donor type alloantigens--namely, irradiated bone marrow cells--were given i.v. either simultaneously or with a delay of not more than 24 hr after the above conditioning regimen. These reactions were alloantigen-specific. They were observed in six different strain combinations with varying donors and recipients. Starting on day 2 after irradiation, i.v. injection of bone marrow gradually lost its effectivity and skin grafts were no longer rejected with uniform rapidity; skin donor marrow given on days 4 or 8 did not accelerate skin graft rejection at all. These data show that for approximately 1-2 days after high-dose total-body irradiation rats are still capable of starting a vigorous immune reaction against i.v.-injected alloantigens. The phenomenon of impaired rejection of skin grafted immediately after high-dose irradiation appears to result from the poor accessibility of skin graft alloantigens during the early postirradiation phase when vascularization of the grafted skin is insufficient

  14. High-dose vitamin C and cancer

    Directory of Open Access Journals (Sweden)

    Ahmet Unlu, M.D.

    2016-01-01

    Full Text Available Vitamin C (ascorbic acid, ascorbate is a basic compound that is of great importance with its role in various enzymatic reactions including the synthesis of collagen, as well as with its redox functions. Vitamin C has become the center of interest in cancer studies, in consequence of the facts that connective tissue changes and vitamin C deficiency were first alleged to be associated with cancer in the 1950s; and that high doses of vitamin C was asserted to be cytotoxic for cancer cells, later on. The results of the first study carried out in the 1970s were promising; but afterwards, the studies were ascertained to be faulty. Despite the positive results achieved from some laboratory and animal experiments, randomized clinical trials did not verify those findings, and no clear benefit of vitamin C for cancer treatment could be demonstrated. As for studies, where its use in combination with other cancer treatment regimens was assessed, conflicting results were obtained. Although intake of high doses of vitamin C is alleged to be harmless, based on that it is in the group of water soluble vitamins and is not stored in the body, there are many side effects and drug interactions reported in the literature. For now, it is better to abstain from this treatment, until the benefit of the treatment (if any is clearly demonstrated, considering the potential side effects and interactions.

  15. Spinal Cord Tolerance to Reirradiation With Single-Fraction Radiosurgery: A Swine Model

    Energy Technology Data Exchange (ETDEWEB)

    Medin, Paul M., E-mail: Paul.medin@utsouthwestern.edu [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Foster, Ryan D. [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Kogel, Albert J. van der [Department of Radiation Oncology, Radboud University Medical Center Nijmegen, Nijmegen (Netherlands); Sayre, James W. [Department of Biostatistics and Radiology, University of California Los Angeles, Los Angeles, California (United States); McBride, William H. [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California (United States); Solberg, Timothy D. [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States)

    2012-07-01

    Purpose: This study was performed to determine swine spinal cord tolerance to single-fraction, partial-volume irradiation 1 year after receiving uniform irradiation to 30 Gy in 10 fractions. Methods and Materials: A 10-cm length of spinal cord (C3-T1) was uniformly irradiated to 30 Gy in 10 consecutive fractions and reirradiated 1 year later with a single radiosurgery dose centered within the previously irradiated segment. Radiosurgery was delivered to a cylindrical volume approximately 5 cm in length and 2 cm in diameter, which was positioned laterally to the cervical spinal cord, resulting in a dose distribution with the 90%, 50%, and 10% isodose lines traversing the ipsilateral, central, and contralateral spinal cord, respectively. Twenty-three pigs were stratified into six dose groups with mean maximum spinal cord doses of 14.9 {+-} 0.1 Gy (n = 2), 17.1 {+-} 0.3 Gy (n = 3), 19.0 {+-} 0.1 Gy (n = 5), 21.2 {+-} 0.1 Gy (n = 5), 23.4 {+-} 0.2 Gy (n = 5), and 25.4 {+-} 0.4 Gy (n = 3). The mean percentage of spinal cord volumes receiving {>=}10 Gy for the same groups were 34% {+-} 1%, 40% {+-} 1%, 46% {+-} 3%, 52% {+-} 1%, 56 {+-} 3%, and 57% {+-} 1%. The study endpoint was motor neurologic deficit as determined by a change in gait during a 1- year follow-up period. Results: A steep dose-response curve was observed with a 50% incidence of paralysis (ED{sub 50}) for the maximum point dose of 19.7 Gy (95% confidence interval, 17.4-21.4). With two exceptions, histology was unremarkable in animals with normal neurologic status, while all animals with motor deficits showed some degree of demyelination and focal white matter necrosis on the irradiated side, with relative sparing of gray matter. Histologic comparison with a companion study of de novo irradiated animals revealed that retreatment responders had more extensive tissue damage, including infarction of gray matter, only at prescription doses >20 Gy. Conclusion: Pigs receiving spinal radiosurgery 1 year after

  16. Response of rat spinal cord to single and fractionated doses of accelerated heavy ions

    International Nuclear Information System (INIS)

    Leith, J.T.; McDonald, M.; Powers-Risius, P.; Bliven, S.F.; Howard, J.

    1982-01-01

    The thoraco-lumbar (T12-L1) region of the spinal cord of rats was exposed to either single or fractionated (four daily exposures) doses of X rays (230 kVp) or heavy ions. The heavy ions used were carbon and neon, and the relative biological effectiveness (RBE) of both the plateau ionization region and the midpeak region of 4-cm spread-out Bragg peaks of each heavy ion were investigated. For single doses of carbon and neon ions in the plateau ionization region, RBE values of 1.45 +/- 0.25 (propagated 95% confidence limits) and 1.46 +/- 0.33, respectively, were obtained. In the spread peak regions for carbon and neon ions, the RBE values were 1.48 +/- 0.18 and 1.86 +/- 0.42, respectively. These values were obtained using the dose needed to produce 50% paralysis in a group of irradiated rats as the isoeffect comparison dose (ED 50 dose). Similarly, in groups of rats receiving four daily exposures, the RBE values for carbon and neon ions in the plateau ionization region were 1.31 +/- 0.27 and 1.80 +/- 0.24, respectively. In the spread peak regions of ionization for carbon and neon ions, the RBE values were 1.95 +/- 0.19 and 2.18 +/- 0.23, respectively. Similar values for RBE were obtained using changes in the activity of enzymes in spinal cord tissue (cyclic nucleotide phosphohydrolase and γ-glutamyl transpeptidase). Also, it was estimated that, for X irradiation, the fractional amount of dose repaired (at the ED 50 dose) was 0.64 +/- 0.10 (95% confidence limits). For carbon and neon ions in the plateau ionization region, the values for the fractional amount of dose repaired were 0.70 +/- 0.27 and 0.48 +/- 0.20, and for carbon and neon ions in the spread peak region of ionization, the fractional repair values were 0.40 +/- 0.10 and 0.52 +/- 0.17. Spinal cord tissue therefore shows a high capacity for subeffective damage repair

  17. 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.

  18. Fractionation and Characterization of High Aspect Ratio Gold Nanorods Using Asymmetric-Flow Field Flow Fractionation and Single Particle Inductively Coupled Plasma Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Thao M. Nguyen

    2015-07-01

    Full Text Available Gold nanorods (GNRs are of particular interest for biomedical applications due to their unique size-dependent longitudinal surface plasmon resonance band in the visible to near-infrared. Purified GNRs are essential for the advancement of technologies based on these materials. Used in concert, asymmetric-flow field flow fractionation (A4F and single particle inductively coupled mass spectrometry (spICP-MS provide unique advantages for fractionating and analyzing the typically complex mixtures produced by common synthetic procedures. A4F fractions collected at specific elution times were analyzed off-line by spICP-MS. The individual particle masses were obtained by conversion of the ICP-MS pulse intensity for each detected particle event, using a defined calibration procedure. Size distributions were then derived by transforming particle mass to length assuming a fixed diameter. The resulting particle lengths correlated closely with ex situ transmission electron microscopy. In contrast to our previously reported observations on the fractionation of low-aspect ratio (AR GNRs (AR < 4, under optimal A4F separation conditions the results for high-AR GNRs of fixed diameter (≈20 nm suggest normal, rather than steric, mode elution (i.e., shorter rods with lower AR generally elute first. The relatively narrow populations in late eluting fractions suggest the method can be used to collect and analyze specific length fractions; it is feasible that A4F could be appropriately modified for industrial scale purification of GNRs.

  19. Single-Fraction Versus 5-Fraction Radiation Therapy for Metastatic Epidural Spinal Cord Compression in Patients With Limited Survival Prognoses: Results of a Matched-Pair Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Rades, Dirk, E-mail: Rades.Dirk@gmx.net [Department of Radiation Oncology, University Hospital Lubeck, Lubeck (Germany); Huttenlocher, Stefan [Department of Radiation Oncology, University Hospital Lubeck, Lubeck (Germany); Šegedin, Barbara; Perpar, Ana [Department of Radiotherapy, Institute of Oncology Ljubljana, Ljubljana (Slovenia); Conde, Antonio J.; Garcia, Raquel [Department of Radiation Oncology, Consorcio Hospital Provincial de Castellón, Castellón (Spain); Veninga, Theo [Department of Radiation Oncology, Dr Bernard Verbeeten Institute, Tilburg (Netherlands); Stalpers, Lukas J.A. [Department of Radiation Oncology, Academic Medical Center, Amsterdam (Netherlands); Cacicedo, Jon [Department of Radiation Oncology, Cruces University Hospital, Barakaldo, Vizcaya (Spain); Rudat, Volker [Department of Radiation Oncology, Saad Specialist Hospital, Al Khobar (Saudi Arabia); Schild, Steven E. [Department of Radiation Oncology, Mayo Clinic, Scottsdale, Arizona (United States)

    2015-10-01

    Purpose: This study compared single-fraction to multi-fraction short-course radiation therapy (RT) for symptomatic metastatic epidural spinal cord compression (MESCC) in patients with limited survival prognosis. Methods and Materials: A total of 121 patients who received 8 Gy × 1 fraction were matched (1:1) to 121 patients treated with 4 Gy × 5 fractions for 10 factors including age, sex, performance status, primary tumor type, number of involved vertebrae, other bone metastases, visceral metastases, interval between tumor diagnosis and MESCC, pre-RT ambulatory status, and time developing motor deficits prior to RT. Endpoints included in-field repeated RT (reRT) for MESCC, overall survival (OS), and impact of RT on motor function. Univariate analyses were performed with the Kaplan-Meier method and log-rank test for in-field reRT for MESCC and OS and with the ordered-logit model for effect of RT on motor function. Results: Doses of 8 Gy × 1 fraction and 4 Gy × 5 fractions were not significantly different with respect to the need for in-field reRT for MESCC (P=.11) at 6 months (18% vs 9%, respectively) and 12 months (30% vs 22%, respectively). The RT regimen also had no significant impact on OS (P=.65) and post-RT motor function (P=.21). OS rates at 6 and 12 months were 24% and 9%, respectively, after 8 Gy × 1 fraction versus 25% and 13%, respectively, after 4 Gy × 5 fractions. Improvement of motor function was observed in 17% of patients after 8 Gy × 1 fraction and 23% after 4 Gy × 5 fractions, respectively. Conclusions: There were no significant differences with respect to need for in-field reRT for MESCC, OS, and motor function by dose fractionation regimen. Thus, 8 Gy × 1 fraction may be a reasonable option for patients with survival prognosis of a few months.

  20. FRACTIONAL CRYSTALLIZATION OF HANFORD SINGLE-SHELL TANK WASTES FROM CONCEPT TO PILOT PLANT

    International Nuclear Information System (INIS)

    GENIESSE, D.J.; NELSON, E.A.; HAMILTON, D.W.; MAJORS, J.H.; NORDAHL, T.K.

    2006-01-01

    The Hanford site has 149 underground single-shell tanks (SST) storing mostly soluble, multi-salt mixed wastes resulting from Cold War era weapons material production. These wastes must be retrieved and the salts immobilized before the tanks can be closed to comply with an overall site-closure consent order entered into by the US Department of Energy, the Environmental Protection Agency, and the State of Washington. Water will be used to retrieve the wastes and the resulting solution will be pumped to a proposed pretreatment process where a high-curie (primarily 137 Cs) waste fraction will be separated from the other waste constituents. The separated waste streams will then be vitrified to allow for safe storage as an immobilized high-level waste, or low-level waste, borosilicate glass. Fractional crystallization, a common unit operation for production of industrial chemicals and pharmaceuticals, was proposed as the method to separate the salt wastes; it works by evaporating excess water until the solubilities of various species in the solution are exceeded (the solubility of a particular species depends on its concentration, temperature of the solution, and the presence of other ionic species in the solution). By establishing the proper conditions, selected pure salts can be crystallized and separated from the radioactive liquid phase. The aforementioned parameters, along with evaporation rate, proper agitation, and residence time, determine nucleation and growth kinetics and the resulting habit and size distribution of the product crystals. These crystals properties are important considerations for designing the crystallizer and solid/liquid separation equipment. A structured program was developed to (a) demonstrate that fractional crystallization could be used to pre-treat Hanford tank wastes and (b) provide data to develop a pilot plant design

  1. FRACTIONAL CRYSTALLIZATION OF HANFORD SINGLE-SHELL TANK WASTES. A MODELING APPROACH

    International Nuclear Information System (INIS)

    HAMILTON, D.W.

    2006-01-01

    The Hanford site has 149 underground single-shell tanks (SST) storing mostly soluble, multi-salt, mixed wastes resulting from Cold War era weapons material production. These wastes must be retrieved and the salts immobilized before the tanks can be closed to comply with an overall site closure consent order entered into by the U.S. Department of Energy (DOE), the Environmental Protection Agency, and Washington State. Water will be used to retrieve the wastes and the resulting solution will be pumped to the proposed treatment process where a high curie (primarily 137 Cs) waste fraction will be separated from the other waste constituents. The separated waste streams will then be vitrified to allow for safe storage as an immobilized high level waste, or low level waste, borosilicate glass. Fractional crystallization, a common unit operation for production of industrial chemicals and pharmaceuticals, was proposed as the method to separate the salt wastes; it works by evaporating excess water until the solubilities of various species in the solution are exceeded (the solubility of a particular species depends on its concentration, temperature of the solution, and the presence of other ionic species in the solution). By establishing the proper conditions, selected pure salts can be crystallized and separated from the radioactive liquid phase

  2. The use of single fraction Leksell stereotactic radiosurgery in the treatment of uveal melanoma

    Energy Technology Data Exchange (ETDEWEB)

    Rennie, I. [Univ. of Sheffield, Dept. of Ophthalmology and Orthoptics (United Kingdom); Forster, D.; Kemeny, A. [Royal Hallamshire Hospital, Dept. of Neurosurgery (United Kingdom); Walton, L. [Royal Hallamshire Hospital, Dept. of Medical Physics (United Kingdom); Kunkler, I. [Weston Park Hospital, Dept. of Radiotherapy, Sheffield (United Kingdom)

    1996-11-01

    Fourteen patients with posterior uveal melanomas were treated using single fraction stereotactic radiosurgery. In each case a dose of 70 Gy was administered to the periphery of the tumour. Regression of the tumour has been observed in 13 patients, whilst the lesion has remained unchanged in one patient. The visual acuity has deteriorated in all 14 patients. Significant radiation induced adverse reactions were noted in 13 patients and include; retinopathy, optic neuropathy, rubeosis iridis, and secondary glaucoma. Two patients have required enucleation because of intractable rubeotic glaucoma. One patient has died from proven metastases. Although stereotactic radiosurgery appears to be a practical and effective method of treating uveal melanomas, its usefulness is limited by a high incidence of radiation induced adverse reactions. Further works is required to refine the current treatment protocol and establish an optimal prescription dose. (au) 30 refs.

  3. The use of single fraction Leksell stereotactic radiosurgery in the treatment of uveal melanoma

    International Nuclear Information System (INIS)

    Rennie, I.; Forster, D.; Kemeny, A.; Walton, L.; Kunkler, I.

    1996-01-01

    Fourteen patients with posterior uveal melanomas were treated using single fraction stereotactic radiosurgery. In each case a dose of 70 Gy was administered to the periphery of the tumour. Regression of the tumour has been observed in 13 patients, whilst the lesion has remained unchanged in one patient. The visual acuity has deteriorated in all 14 patients. Significant radiation induced adverse reactions were noted in 13 patients and include; retinopathy, optic neuropathy, rubeosis iridis, and secondary glaucoma. Two patients have required enucleation because of intractable rubeotic glaucoma. One patient has died from proven metastases. Although stereotactic radiosurgery appears to be a practical and effective method of treating uveal melanomas, its usefulness is limited by a high incidence of radiation induced adverse reactions. Further works is required to refine the current treatment protocol and establish an optimal prescription dose. (au) 30 refs

  4. NIST high-dose calibration services

    International Nuclear Information System (INIS)

    Humphreys, J.C.

    1989-01-01

    There is a need for the standardization of high-dose measurements used in the radiation-processing industry in order to provide assured traceability to national standards. NIST provides dosimetry calibration services to this industry. One of these services involves administration of known absorbed doses of gamma rays to customer-supplied dosimeters. The dosimeters are packaged to provide electron equilibrium conditions and are irradiated in a standard 60 Co calibration facility; this provides a calibration of that batch of dosimeters. Another service consists of supplying to a customer calibrated transfer dosimeters for irradiation with the customer's radiation source. The irradiated transfer dosimeters are then returned to NIST for analysis; the results are reported to the customer, providing a calibration of the dose rate of the customer's source. (orig.)

  5. Onyx as radiation detector for high doses

    International Nuclear Information System (INIS)

    Teixeira, Maria Inês; Souza, Divanizia N.; Caldas, Linda V.E.

    2011-01-01

    A study of the thermoluminescent (TL) characteristics of white, black and stripped onyx samples is reported in this work. Onyx is a variety of chalcedony, a form of quartz. The onyx stone is considered nobler than marble. The irradiations were performed using a Gamma-Cell 220 system ( 60 Co). The TL emission curves presented two peaks around 150 °C and 210 °C for all samples. The dose–response curves showed a sublinear behavior between 0.5 Gy and 5 kGy, and the lower detection limit for the white onyx pellets was 1.5 mGy. The main dosimetric characteristics were studied, and the material showed good performance for high dose dosimetry.

  6. Randomized trial of single dose versus fractionated palliative radiotherapy of bone metastases

    International Nuclear Information System (INIS)

    Nielsen, O.S.; Bentzen, S.M.; Sandberg, E.; Gadeberg, C.C.; Timothy, A.R.

    1998-01-01

    Purpose: Data in the literature suggest that for painful bone metastases a single dose is as effective as fractionated radiotherapy. In the present multicentre prospective trial, the effects of 8 Gy x1 and 5 Gy x4 were compared. Patients and methods: A total of 241 patients were randomized to 8 Gy (122 patients) or 20 Gy (119 patients). The primary tumour was in the breast in 39% of patients, in the prostate in 34% of patients, in the lung in 13% of patients and in other locations in 14% of patients. Outcome measures were pain relief as measured by VAS and in half of the patients also by a five-point categorical pain scale, global quality of life (QoL) and analgesic consumption. Evaluation was performed before and 4, 8, 12 and 20 weeks after treatment. Results: A total of 239 patients were evaluable for response. The two groups did not differ with respect to age, sex, primary tumour, metastasis localization, analgesic consumption (type and dose), performance status, prior systemic treatment, degree of pain and QoL. The treatment was completed as planned in 98% of patients. The degree of pain relief did not differ between the two treatment groups. At 4 weeks the difference in pain relief was 6% (95% CI 7, 20%) and at 8 weeks the difference was 13% (95% CI 3, 28%). Neither was there any significant difference in the duration of pain relief, the number of new painful sites and the need for reirradiation and toxicity was minor. Conclusion: The present randomized study showed that a single fraction of 8 Gy was as effective as 5 Gy x4 in relieving pain from bone metastasis. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  7. Nonlinear model of high-dose implantation

    International Nuclear Information System (INIS)

    Danilyuk, A.

    2001-01-01

    The models of high-dose implantation, using the distribution functions, are relatively simple. However, they must take into account the variation of the function of distribution of the implanted ions with increasing dose [1-4]. This variation takes place owing to the fact that the increase of the concentration of the implanted ions results in a change of the properties of the target. High-dose implantation is accompanied by sputtering, volume growth, diffusion, generation of defects, formation of new phases, etc. The variation of the distribution function is determined by many factors and is not known in advance. The variation within the framework of these models [1-4] is taken into account in advance by the introduction of intuitive assumptions on the basis of implicit considerations. Therefore, these attempts should be regarded as incorrect. The model prepared here makes it possible to take into account the sputtering of the target, volume growth and additional declaration on the implanted ions. Without any assumptions in relation to the variation of the distribution function with increasing dose. In our model it is assumed that the type of distribution function for small doses in a pure target substance is the same as in substances with implanted ions. A second assumption relates to the type of the distribution function valid for small doses in the given substances. These functions are determined as a result of a large number of theoretical and experimental investigations and are well-known at the present time. They include the symmetric and nonsymmetric Gauss distribution, the Pearson distribution, and others. We examine implantation with small doses of up to 10 14 - 10 15 cm -2 when the accurately known distribution is valid

  8. Safety aspects of preoperative high-dose glucocorticoid in primary total knee replacement

    DEFF Research Database (Denmark)

    Jørgensen, C C; Pitter, F T; Kehlet, H

    2017-01-01

    Background: Preoperative single high-dose glucocorticoid may have early outcome benefits in total hip arthroplasty (THA) and knee arthroplasty (TKA), but long-term safety aspects have not been evaluated. Methods: From October 2013, the departments reporting to the prospective Lundbeck Foundation....... Conclusions: In this detailed prospective cohort study, preoperative high-dose glucocorticoid administration was not associated with LOS >4 days, readmissions or infectious complications in TKA patients without contraindications....

  9. Experience of micromultileaf collimator linear accelerator based single fraction stereotactic radiosurgery: Tumor dose inhomogeneity, conformity, and dose fall off

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Linda X.; Garg, Madhur; Lasala, Patrick; Kim, Mimi; Mah, Dennis; Chen, Chin-Cheng; Yaparpalvi, Ravindra; Mynampati, Dinesh; Kuo, Hsiang-Chi; Guha, Chandan; Kalnicki, Shalom [Department of Radiation Oncology, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, New York 10461 (United States); Department of Neurosurgery, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, New York 10461 (United States); Department of Epidemiology and Population Health, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, New York 10461 (United States); Department of Radiation Oncology, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, New York 10461 (United States)

    2011-03-15

    Purpose: Sharp dose fall off outside a tumor is essential for high dose single fraction stereotactic radiosurgery (SRS) plans. This study explores the relationship among tumor dose inhomogeneity, conformity, and dose fall off in normal tissues for micromultileaf collimator (mMLC) linear accelerator (LINAC) based cranial SRS plans. Methods: Between January 2007 and July 2009, 65 patients with single cranial lesions were treated with LINAC-based SRS. Among them, tumors had maximum diameters {<=}20 mm: 31; between 20 and 30 mm: 21; and >30 mm: 13. All patients were treated with 6 MV photons on a Trilogy linear accelerator (Varian Medical Systems, Palo Alto, CA) with a tertiary m3 high-resolution mMLC (Brainlab, Feldkirchen, Germany), using either noncoplanar conformal fixed fields or dynamic conformal arcs. The authors also created retrospective study plans with identical beam arrangement as the treated plan but with different tumor dose inhomogeneity by varying the beam margins around the planning target volume (PTV). All retrospective study plans were normalized so that the minimum PTV dose was the prescription dose (PD). Isocenter dose, mean PTV dose, RTOG conformity index (CI), RTOG homogeneity index (HI), dose gradient index R{sub 50}-R{sub 100} (defined as the difference between equivalent sphere radius of 50% isodose volume and prescription isodose volume), and normal tissue volume (as a ratio to PTV volume) receiving 50% prescription dose (NTV{sub 50}) were calculated. Results: HI was inversely related to the beam margins around the PTV. CI had a ''V'' shaped relationship with HI, reaching a minimum when HI was approximately 1.3. Isocenter dose and mean PTV dose (as percentage of PD) increased linearly with HI. R{sub 50}-R{sub 100} and NTV{sub 50} initially declined with HI and then reached a plateau when HI was approximately 1.3. These trends also held when tumors were grouped according to their maximum diameters. The smallest tumor group

  10. Radiobiological restrictions and tolerance doses of repeated single-fraction hdr-irradiation of intersecting small liver volumes for recurrent hepatic metastases

    Directory of Open Access Journals (Sweden)

    Wust Peter

    2010-05-01

    Full Text Available Abstract Background To assess radiobiological restrictions and tolerance doses as well as other toxic effects derived from repeated applications of single-fraction high dose rate irradiation of small liver volumes in clinical practice. Methods Twenty patients with liver metastases were treated repeatedly (2 - 4 times at identical or intersecting locations by CT-guided interstitial brachytherapy with varying time intervals. Magnetic resonance imaging using the hepatocyte selective contrast media Gd-BOPTA was performed before and after treatment to determine the volume of hepatocyte function loss (called pseudolesion, and the last acquired MRI data set was merged with the dose distributions of all administered brachytherapies. We calculated the BED (biologically equivalent dose for a single dose d = 2 Gy for different α/β values (2, 3, 10, 20, 100 based on the linear-quadratic model and estimated the tolerance dose for liver parenchyma D90 as the BED exposing 90% of the pseudolesion in MRI. Results The tolerance doses D90 after repeated brachytherapy sessions were found between 22 - 24 Gy and proved only slightly dependent on α/β in the clinically relevant range of α/β = 2 - 10 Gy. Variance analysis showed a significant dependency of D90 with respect to the intervals between the first irradiation and the MRI control (p 90 and the pseudolesion's volume. No symptoms of liver dysfunction or other toxic effects such as abscess formation occurred during the follow-up time, neither acute nor on the long-term. Conclusions Inactivation of liver parenchyma occurs at a BED of approx. 22 - 24 Gy corresponding to a single dose of ~10 Gy (α/β ~ 5 Gy. This tolerance dose is consistent with the large potential to treat oligotopic and/or recurrent liver metastases by CT-guided HDR brachytherapy without radiation-induced liver disease (RILD. Repeated small volume irradiation may be applied safely within the limits of this study.

  11. Therapeutic profile of single-fraction radiosurgery of vestibular schwannoma: unrelated malignancy predicts tumor control

    Science.gov (United States)

    Wowra, Berndt; Muacevic, Alexander; Fürweger, Christoph; Schichor, Christian; Tonn, Jörg-Christian

    2012-01-01

    Radiosurgery has become an accepted treatment option for vestibular schwannomas. Nevertheless, predictors of tumor control and treatment toxicity in current radiosurgery of vestibular schwannomas are not well understood. To generate new information on predictors of tumor control and cranial nerve toxicity of single-fraction radiosurgery of vestibular schwannomas, we conducted a single-institution long-term observational study of radiosurgery for sporadic vestibular schwannomas. Minimum follow-up was 3 years. Investigated as potential predictors of tumor control and cranial nerve toxicity were treatment technology; tumor resection preceding radiosurgery; tumor size; gender; patient age; history of cancer, vascular disease, or metabolic disease; tumor volume; radiosurgical prescription dose; and isodose line. Three hundred eighty-six patients met inclusion criteria. Treatment failure was observed in 27 patients. History of unrelated cancer (strongest predictor) and prescription dose significantly predicted tumor control. The cumulative incidence of treatment failure was 30% after 6.5 years in patients with unrelated malignancy and 10% after ≥15 years in patients without such cancer (P making in ambiguous cases. PMID:22561798

  12. Isotachophoresis for fractionation and recovery of cytoplasmic RNA and nucleus from single cells.

    Science.gov (United States)

    Kuriyama, Kentaro; Shintaku, Hirofumi; Santiago, Juan G

    2015-07-01

    There is a substantial need for simultaneous analyses of RNA and DNA from individual single cells. Such analysis provides unique evidence of cell-to-cell differences and the correlation between gene expression and genomic mutation in highly heterogeneous cell populations. We present a novel microfluidic system that leverages isotachophoresis to fractionate and isolate cytoplasmic RNA and genomic DNA (gDNA) from single cells. The system uniquely enables independent, sequence-specific analyses of these critical markers. Our system uses a microfluidic chip with a simple geometry and four end-channel electrodes, and completes the entire process in RNA output reservoirs, each containing high quality and purity aliquots with no measurable cross-contamination of cytoplasmic RNA versus gDNA. We demonstrate our system with simultaneous, sequence-specific quantitation using off-chip RT-qPCR and qPCR for simultaneous cytoplasmic RNA and gDNA analyses, respectively. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Pathologic changes in the lung following single and multi-fraction irradiation

    International Nuclear Information System (INIS)

    Travis, E.L.; Harley, R.A.; Fenn, J.O.; Klobukowski, C.J.; Hargrove, H.B.

    1977-01-01

    The limiting factor in the treatment of malignant disease with irradiation is the tolerance of normal tissue irradiated. In the present study the right lungs of rats were exposed to single doses of 2000 rad of x-radiation, to 10 x 200 rad, or to 5 x 400 rad. Animals from each group were sacrificed monthly for 6 months post exposure. Sections of lung were examined by light microscopy (LM) and by scanning or transmission electron microscopy (SEM and TEM). A focal exudative lesion was seen at 2 months after the single dose; it progressed to a proliferative and then reparative, fibrotic lesion by 6 months. Changes in epithelial lung components, particularly the presence of Type II pneumocytes, were found with both LM and TM. Vascular changes were less pronounced. A striking finding was the presence of mast cells in the alveolar walls. Neither of the multi-fraction schedules produced any of these changes, except hyperplasia of Type II cells following 5 x 400 rad. The possible implication of Type II and mast cells in radiation pneumonitis and fibrosis is discussed

  14. Implication of fractionated dose exposures in therapeutic gain

    International Nuclear Information System (INIS)

    Kim, Hye-Jin; Lee, Min-Ho; Kim, Eun-Hee

    2016-01-01

    Radiation therapy pursues killing tumor cells while sparing normal cells from the radiation exposure. Stereotactic radiosurgery (SRS) is a cancer treatment modality that delivers a high dose in a single operation. This high-dose single operation shortens the treatment course, but can increase the risk of normal cell damage. Normal cell damage can be reduced by employing multi-directional exposures for an increasing number of isocenters. In this study, we investigated whether therapeutic benefits would be expected by employing new dose fractionation patterns at a high-dose single operation. The conventional single-dose operation in brain tumor radiosurgery is performed by delivering fractionated uniform doses. According to Figs. 2 and 3, the conventional radiosurgery might have obtained some therapeutic benefit by employing the fractionated uniform-dose exposures instead of a single-dose exposure. We suggest that further therapeutic gain be expected by employing the fractionated radiation exposures in an increasing dose pattern. Until ensuring our suggestion, the significance in gain of cell surviving should be verified for all three dose patterns with both normal and tumor cells. The investigation whether normal and tumor cells show the same responses to the fractionated dose exposures at lower and higher than 15 Gy of total dose is also reserved for future work

  15. Prehospital high-dose sublingual nitroglycerin rarely causes hypotension.

    Science.gov (United States)

    Clemency, Brian M; Thompson, Jeffrey J; Tundo, Gina N; Lindstrom, Heather A

    2013-10-01

    High-dose intravenous nitroglycerin is a common in-hospital treatment for respiratory distress due to congestive heart failure (CHF) with hypertension. Intravenous (IV) nitroglycerin administration is impractical in the prehospital setting. In 2011, a new regional Emergency Medical Services (EMS) protocol was introduced allowing advanced providers to treat CHF with high-dose oral nitroglycerin. The protocol calls for patients to be treated with two sublingual tabs (0.8 mg) when systolic blood pressure (SBP) was >160 mm Hg, or three sublingual tabs (1.2 mg) when SBP was >200 mm Hg, every five minutes as needed. Hypothesis/Problem To assess the protocol's safety, the incidence of hypotension following prehospital administration of multiple simultaneous nitroglycerin (MSN) tabs by EMS providers was studied. This study was a retrospective cohort study of patients from a single commercial EMS agency over a 6-month period. Records from patients with at least one administration of MSN were reviewed. For each administration, the first documented vital signs pre- and post-administration were compared. Administrations were excluded if pre- or post-administration vital signs were missing. One hundred case-patients had at least one MSN administration by an advanced provider during the study period. Twenty-five case-patients were excluded due to incomplete vital signs. Seventy-five case-patients with 95 individual MSN administrations were included for analysis. There were 65 administrations of two tabs, 29 administrations of three tabs, and one administration of four tabs. The mean change in SBP following MSN was -14.7 mm Hg (SD = 30.7; range, +59 to -132). Three administrations had documented systolic hypotension in the post-administration vital signs (97/71, 78/50 and 66/47). All three patients were over 65 years old, were administered two tabs, had documented improved respiratory status, and had repeat SBP of at least 100. The incidence of hypotension following MSN

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

    International Nuclear Information System (INIS)

    Einck, John P.; Hudson, Alana; Shulman, Adam C.; Yashar, Catheryn M.; Dieng, Mamadou M.; Diagne, Magatte; Gueye, Latifatou; Gningue, Fama; Gaye, Pape M.; Fisher, Brandon J.; Mundt, Arno J.; Brown, Derek W.

    2014-01-01

    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 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

  17. 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.

  18. 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.

  19. Single vs. multiple fraction regimens for palliative radiotherapy treatment of multiple myeloma. A prospective randomised study

    Energy Technology Data Exchange (ETDEWEB)

    Rudzianskiene, Milda; Inciura, Arturas; Gerbutavicius, Rolandas; Rudzianskas, Viktoras; Dambrauskiene, Ruta; Juozaityte, Elona [Lithuanian University of Health Sciences, Oncology Institute, Kaunas (Lithuania); Macas, Andrius [Lithuanian University of Health Sciences, Anaesthesiology Department, Kaunas (Lithuania); Simoliuniene, Renata [Lithuanian University of Health Sciences, Department of Physics, Mathematics and Biophysics, Kaunas (Lithuania); Kiavialaitis, Greta Emilia [University Hospital Zurich, Intitute of Anesthesiology, Zurich (Switzerland)

    2017-09-15

    To compare the impact of a single fraction (8 Gy x 1 fraction) and multifraction (3 Gy x 10 fractions) radiotherapy regimens on pain relief, recalcification and the quality of life (QoL) in patients with bone destructions due to multiple myeloma (MM). In all, 101 patients were included in a randomised prospective clinical trial: 58 patients were included in the control arm (3 Gy x 10 fractions) and 43 patients into the experimental arm (8 Gy x 1 fraction). The response rate was defined according to the International Consensus on Palliative Radiotherapy criteria. Recalcification was evaluated with radiographs. QoL questionnaires were completed before and 4 weeks after treatment. Pain relief was obtained in 81/101 patients (80.2%): complete response in 56 (69%) and partial in 25 patients (30.9%). No significant differences were observed in analgesic response between the groups. Significant factors for pain relief were female gender, age under 65, IgG MM type, presence of recalcification at the irradiated site. Recalcification was found in 32/101 patients (33.7%): complete in 17 (53.2%) and partial in 15 (46.2%). No significant differences were observed in recalcification between the groups. Significant factors for recalcification were Karnofsky index ≥ 60%, haemoglobin level ≤ 80 g/dl, MM stage II and analgesic response at the irradiated site. The QoL after radiotherapy was improved in the control group. The same analgesic and recalcification response was observed using two different radiotherapy regimens. Higher doses should be used to achieve a better QoL. (orig.) [German] Vergleich der einzeitigen vs. fraktionierten palliativen Radiotherapie in Bezug auf Schmerzlinderung, Knochenrekalzifizierung und Lebensqualitaet (QoL) bei Patienten mit multiplem Myelom (MM). In die randomisierte, prospektive Studie wurden 101 Patienten eingeschlossen: Die Kontrollgruppe (n = 58) erhielt eine fraktionierte (3 Gy x 10 Fraktionen) und die Experimentgruppe (n = 43) eine

  20. Effectiveness and toxicity of single-fraction radiotherapy with 1x8 Gy for metastatic spinal cord compression

    International Nuclear Information System (INIS)

    Rades, Dirk; Stalpers, Lukas J.A.; Hulshof, Maarten C.C.M.; Zschenker, Oliver; Alberti, Winfried; Koning, Caro C.E.

    2005-01-01

    Toxicity and functional outcome were evaluated in 199 MSCC-patients irradiated with 1x8 Gy. Motor function improved in 54/199 patients (27%). Patients who regained walking ability were 20/78 (26%). Long-term-survivors (≥12 months) who needed re-irradiation for in-field-recurrence were 19/65 (29%). Acute toxicity was mild, late toxicity not observed. A randomised trial comparing single-fraction RT to multi-fraction RT is mandatory

  1. Effectiveness and toxicity of single-fraction radiotherapy with 1x8 Gy for metastatic spinal cord compression

    Energy Technology Data Exchange (ETDEWEB)

    Rades, Dirk [Department of Radiation Oncology, University Hospital Hamburg-Eppendorf, Hamburg (Germany) and Department of Radiotherapy, Academic Medical Center, Amsterdam (Netherlands); Stalpers, Lukas J.A. [Department of Radiotherapy, Academic Medical Center, Amsterdam (Netherlands); Hulshof, Maarten C.C.M. [Department of Radiotherapy, Academic Medical Center, Amsterdam (Netherlands); Zschenker, Oliver [Department of Radiation Oncology, Section Radiobiology, University Hospital Hamburg-Eppendorf, Hamburg (Germany); Alberti, Winfried [Department of Radiation Oncology, University Hospital Hamburg-Eppendorf, Hamburg (Germany); Koning, Caro C.E. [Department of Radiotherapy, Academic Medical Center, Amsterdam (Netherlands)

    2005-04-01

    Toxicity and functional outcome were evaluated in 199 MSCC-patients irradiated with 1x8 Gy. Motor function improved in 54/199 patients (27%). Patients who regained walking ability were 20/78 (26%). Long-term-survivors ({>=}12 months) who needed re-irradiation for in-field-recurrence were 19/65 (29%). Acute toxicity was mild, late toxicity not observed. A randomised trial comparing single-fraction RT to multi-fraction RT is mandatory.

  2. Fractionated stereotactic radiotherapy in patients with acromegaly: an interim single-centre audit

    DEFF Research Database (Denmark)

    Roug, Anne Stidsholt; Rasmussen, Åse Krogh; Juhler, M

    2010-01-01

    To evaluate the effect of fractionated stereotactic radiotherapy (FSRT) in acromegaly in a retrospective analysis.......To evaluate the effect of fractionated stereotactic radiotherapy (FSRT) in acromegaly in a retrospective analysis....

  3. Brachytherapy treatment with high dose rate

    International Nuclear Information System (INIS)

    Santana Rodriguez, Sergio Marcelino; Rodriguez Rodriguez, Lissi Lisbet; Ciscal Chiclana, Onelio Alberto

    2009-01-01

    Retrospectively analyze results and prognostic factors of cervical cancer patients treated with radio concomitant cisplatin-based chemotherapy, radiation therapy combined modality. Methods: From January 2003 to December 2007, 198 patients with invasive cervical cancer were treated at the Oncology Department of Hospital Robau Celestino Hernandez (brachytherapy performed at INOR). The most common age group was 31 to 40 years. The histology in squamous cell carcinoma accounted for 84.3% of cases. The treatment consisted of external pelvic irradiation and vaginal brachytherapy, high dose rate. Concomitant chemotherapy consisted of cisplatin 40 mg/m2 weekly with a maximum of 70 mg for 5 weeks. Results: 66.2% of patients completed 5 cycles of chemotherapy. The median overall survival was 39 months, overall survival, disease-free survival and survival free of locoregional recurrence at 5 years of 78%, 76% and 78.6% respectively .. We found that clinical stage, histological type (adenocarcinoma worst outcome) were statistically related to level of response. Conclusions: Treatment with external pelvic radiation, brachytherapy and concurrent weekly cisplatin in patients with stage IIIB cervical cancer is feasible in the Chilean public health system, well tolerated and results comparable to international literature. (Author)

  4. Single-fraction Radiosurgery for Presumed Intracranial Meningiomas: Efficacy and Complications From a 22-Year Experience

    Energy Technology Data Exchange (ETDEWEB)

    Pollock, Bruce E., E-mail: pollock.bruce@mayo.edu [Department of Neurological Surgery, Mayo Clinic College of Medicine, Rochester, MN (United States); Department of Radiation Oncology, Mayo Clinic College of Medicine, Rochester, MN (United States); Stafford, Scott L. [Department of Radiation Oncology, Mayo Clinic College of Medicine, Rochester, MN (United States); Link, Michael J. [Department of Neurological Surgery, Mayo Clinic College of Medicine, Rochester, MN (United States); Garces, Yolanda I.; Foote, Robert L. [Department of Radiation Oncology, Mayo Clinic College of Medicine, Rochester, MN (United States)

    2012-08-01

    Purpose: To define the rate of tumor control and factors associated with radiation-related complications after single-fraction radiosurgery (SRS) for patients with imaging defined intracranial meningiomas. Materials and Methods: Retrospective review of 251 patients (192 women, 59 men) having SRS for imaging-defined intracranial meningiomas between 1990 and 2008. Excluded were patients with radiation-induced tumors, meningiomatosis, or neurofibromatosis. The mean patient age was 58.6 {+-} 13.4 years. The majority of tumors involved the skull base/tentorium (n = 210, 83.7%). The mean treatment volume was 7.7 {+-} 6.2 cm{sup 3}; the mean tumor margin dose was 15.8 {+-} 2.0 Gy. Follow-up (mean, 62.9 {+-} 43.9 months) was censored at last evaluation (n = 224), death (n = 22), or tumor resection (n = 5). Results: No patient died from tumor progression or radiation-related complications. Tumor size decreased in 181 patients (72.1%) and was unchanged in 67 patients (26.7%). Three patients (1.2%) had in-field tumor progression noted at 28, 145, and 150 months, respectively. No patient had a marginal tumor progression. The 3- and 10-year local control rate was 99.4%. One patient had distant tumor progression at 105 months and underwent repeat SRS. Thirty-one patients (12.4%) had either temporary (n = 8, 3.2%) or permanent (n = 23, 9.2%) symptomatic radiation-related complications including cranial nerve deficits (n = 14), headaches (n = 5), hemiparesis (n = 5), new/worsened seizure (n = 4), cyst-formation (n = 1), hemifacial spasm (n = 1), and stroke (n = 1). The 1- and 5-year complication rates were 8.3% and 11.5%, respectively. Radiation-related complications were associated with convexity/falx tumors (HR = 2.8, 95% CI 1.3-6.1, p = 0.009) and increasing tumor volume (HR = 1.05, 95% CI 1.0-1.1, p = 0.04) on multivariate analysis. No patient developed a radiation-induced tumor. Conclusions: Single-fraction SRS at the used dose range provides a high rate of tumor control for

  5. Single-fraction Radiosurgery for Presumed Intracranial Meningiomas: Efficacy and Complications From a 22-Year Experience

    International Nuclear Information System (INIS)

    Pollock, Bruce E.; Stafford, Scott L.; Link, Michael J.; Garces, Yolanda I.; Foote, Robert L.

    2012-01-01

    Purpose: To define the rate of tumor control and factors associated with radiation-related complications after single-fraction radiosurgery (SRS) for patients with imaging defined intracranial meningiomas. Materials and Methods: Retrospective review of 251 patients (192 women, 59 men) having SRS for imaging-defined intracranial meningiomas between 1990 and 2008. Excluded were patients with radiation-induced tumors, meningiomatosis, or neurofibromatosis. The mean patient age was 58.6 ± 13.4 years. The majority of tumors involved the skull base/tentorium (n = 210, 83.7%). The mean treatment volume was 7.7 ± 6.2 cm 3 ; the mean tumor margin dose was 15.8 ± 2.0 Gy. Follow-up (mean, 62.9 ± 43.9 months) was censored at last evaluation (n = 224), death (n = 22), or tumor resection (n = 5). Results: No patient died from tumor progression or radiation-related complications. Tumor size decreased in 181 patients (72.1%) and was unchanged in 67 patients (26.7%). Three patients (1.2%) had in-field tumor progression noted at 28, 145, and 150 months, respectively. No patient had a marginal tumor progression. The 3- and 10-year local control rate was 99.4%. One patient had distant tumor progression at 105 months and underwent repeat SRS. Thirty-one patients (12.4%) had either temporary (n = 8, 3.2%) or permanent (n = 23, 9.2%) symptomatic radiation-related complications including cranial nerve deficits (n = 14), headaches (n = 5), hemiparesis (n = 5), new/worsened seizure (n = 4), cyst-formation (n = 1), hemifacial spasm (n = 1), and stroke (n = 1). The 1- and 5-year complication rates were 8.3% and 11.5%, respectively. Radiation-related complications were associated with convexity/falx tumors (HR = 2.8, 95% CI 1.3–6.1, p = 0.009) and increasing tumor volume (HR = 1.05, 95% CI 1.0–1.1, p = 0.04) on multivariate analysis. No patient developed a radiation-induced tumor. Conclusions: Single-fraction SRS at the used dose range provides a high rate of tumor control for patients

  6. Single-Fraction Proton Beam Stereotactic Radiosurgery for Cerebral Arteriovenous Malformations

    Energy Technology Data Exchange (ETDEWEB)

    Hattangadi-Gluth, Jona A. [Department of Radiation Medicine and Applied Sciences, University of California San Diego, San Diego, California (United States); Chapman, Paul H. [Department of Neurosurgery, Massachusetts General Hospital, Boston, Massachusetts (United States); Kim, Daniel; Niemierko, Andrzej; Bussière, Marc R.; Stringham, Alison; Daartz, Juliane [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Ogilvy, Christopher [Department of Neurosurgery, Beth Israel Deaconess Medical Center, Boston, Massachusetts (United States); Loeffler, Jay S. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Shih, Helen A., E-mail: hshih@partners.org [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)

    2014-06-01

    Purpose/Objective(s): To evaluate the obliteration rate and potential adverse effects of single-fraction proton beam stereotactic radiosurgery (PSRS) in patients with cerebral arteriovenous malformations (AVMs). Methods and Materials: From 1991 to 2010, 248 consecutive patients with 254 cerebral AVMs received single-fraction PSRS at our institution. The median AVM nidus volume was 3.5 cc (range, 0.1-28.1 cc), 23% of AVMs were in critical/deep locations (basal ganglia, thalamus, or brainstem), and the most common prescription dose was 15 Gy(relative biological effectiveness [RBE]). Univariable and multivariable analyses were performed to assess factors associated with obliteration and hemorrhage. Results: At a median follow-up time of 35 months (range, 6-198 months), 64.6% of AVMs were obliterated. The median time to total obliteration was 31 months (range, 6-127 months), and the 5-year and 10-year cumulative incidence of total obliteration was 70% and 91%, respectively. On univariable analysis, smaller target volume (hazard ratio [HR] 0.78, 95% confidence interval [CI] 0.86-0.93, P<.0001), smaller treatment volume (HR 0.93, 95% CI 0.90-0.96, P<.0001), higher prescription dose (HR 1.16, 95% CI 1.07-1.26, P=.001), and higher maximum dose (HR 1.14, 95% CI 1.05-1.23, P=.002) were associated with total obliteration. Deep/critical location was also associated with decreased likelihood of obliteration (HR 0.68, 95% CI 0.47-0.98, P=.04). On multivariable analysis, critical location (adjusted HR [AHR] 0.42, 95% CI 0.27-0.65, P<.001) and smaller target volume (AHR 0.81, 95% CI 0.68-0.97, P=.02) remained associated with total obliteration. Posttreatment hemorrhage occurred in 13 cases (5-year cumulative incidence of 7%), all among patients with less than total obliteration, and 3 of these events were fatal. The most common complication was seizure, controlled with medications, both acutely (8%) and in the long term (9.1%). Conclusions: The current series is the largest

  7. Cell kinetic changes in the follicular epithelium of pig skin after irradiation with single and fractionated doses of X rays

    International Nuclear Information System (INIS)

    Morris, G.M.; Hopewell, J.W.

    1989-01-01

    Changes in cell kinetics of the follicular epithelium of the pig were studied after x-irradiation with single and fractionated doses (30 fractions/39 days) and compared with previous epidermal data. In the follicular epithelium there was an initial degenerative phase, when the rate of cell depletion was independent of radiation dose and mode of administration. Repopulation was seen between the 14th and 18th days after single doses (15 or 20 Gy) and by the 28th day after the start of irradiation with fractionated doses (52.3-80.0 Gy). The degree of cell depletion and subsequent rate of repopulation were independent of dose. The regenerative phase was characterized by an increased cell proliferation. Islands of cells with appearance similar to cells in the normal follicular epithelium, were seen 18 days after a single dose of 20 Gy and 42 days after the start of fractionated irradiation. Compared with the epidermis, the follicular epithelium exhibited considerably less evidence of damage after both single and fractionated doses. There was a lower incidence of degenerate cells and reduced levels of cell depletion in the follicular epithelium. (author)

  8. Outcome of Patients Treated With a Single-Fraction Dose of Palliative Radiation for Cutaneous T-Cell Lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Tarita O.; Agrawal, Priya [Department of Radiation Oncology, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States); Guitart, Joan [Department of Dermatology, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States); Rosen, Steven T. [Division of Hematology/Oncology, Department of Medicine, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States); Rademaker, Alfred W. [Department of Preventive Medicine, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States); Querfeld, Christiane [Department of Medicine/Dermatology Service, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Hayes, John P. [Department of Radiation Oncology, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States); Kuzel, Timothy M. [Division of Hematology/Oncology, Department of Medicine, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States); Mittal, Bharat B., E-mail: bmittal@nmh.org [Department of Radiation Oncology, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States)

    2013-03-01

    Purpose: Cutaneous T-cell lymphoma (CTCL) is a radiosensitive tumor. Presently, treatment with radiation is given in multiple fractions. The current literature lacks data that support single-fraction treatment for CTCL. This retrospective review assesses the clinical response in patients treated with a single fraction of radiation. Methods and Materials: This study reviewed the records of 58 patients with CTCL, primarily mycosis fungoides, treated with a single fraction of palliative radiation therapy (RT) between October 1991 and January 2011. Patient and tumor characteristics were reviewed. Response rates were compared using Fisher's exact test and multiple logistic regressions. Survival rates were determined using the Kaplan-Meier method. Cost-effectiveness analysis was performed to assess the cost of a single vs a multifractionated treatment regimen. Results: Two hundred seventy individual lesions were treated, with the majority (97%) treated with ≥700 cGy; mean follow-up was 41.3 months (range, 3-180 months). Response rate by lesion was assessed, with a complete response (CR) in 255 (94.4%) lesions, a partial response in 10 (3.7%) lesions, a partial response converted to a CR after a second treatment in 4 (1.5%) lesions, and no response in 1 (0.4%) lesion. The CR in lower extremity lesions was lower than in other sites (P=.0016). Lesions treated with photons had lower CR than those treated with electrons (P=.017). Patients with lesions exhibiting large cell transformation and tumor morphology had lower CR (P=.04 and P=.035, respectively). Immunophenotype did not impact response rate (P=.23). Overall survival was significantly lower for patients with Sézary syndrome (P=.0003) and erythroderma (P<.0001). The cost of multifractionated radiation was >200% higher than that for single-fraction radiation. Conclusions: A single fraction of 700 cGy-800 cGy provides excellent palliation for CTCL lesions and is cost effective and convenient for the patient.

  9. Outcome of Patients Treated With a Single-Fraction Dose of Palliative Radiation for Cutaneous T-Cell Lymphoma

    International Nuclear Information System (INIS)

    Thomas, Tarita O.; Agrawal, Priya; Guitart, Joan; Rosen, Steven T.; Rademaker, Alfred W.; Querfeld, Christiane; Hayes, John P.; Kuzel, Timothy M.; Mittal, Bharat B.

    2013-01-01

    Purpose: Cutaneous T-cell lymphoma (CTCL) is a radiosensitive tumor. Presently, treatment with radiation is given in multiple fractions. The current literature lacks data that support single-fraction treatment for CTCL. This retrospective review assesses the clinical response in patients treated with a single fraction of radiation. Methods and Materials: This study reviewed the records of 58 patients with CTCL, primarily mycosis fungoides, treated with a single fraction of palliative radiation therapy (RT) between October 1991 and January 2011. Patient and tumor characteristics were reviewed. Response rates were compared using Fisher's exact test and multiple logistic regressions. Survival rates were determined using the Kaplan-Meier method. Cost-effectiveness analysis was performed to assess the cost of a single vs a multifractionated treatment regimen. Results: Two hundred seventy individual lesions were treated, with the majority (97%) treated with ≥700 cGy; mean follow-up was 41.3 months (range, 3-180 months). Response rate by lesion was assessed, with a complete response (CR) in 255 (94.4%) lesions, a partial response in 10 (3.7%) lesions, a partial response converted to a CR after a second treatment in 4 (1.5%) lesions, and no response in 1 (0.4%) lesion. The CR in lower extremity lesions was lower than in other sites (P=.0016). Lesions treated with photons had lower CR than those treated with electrons (P=.017). Patients with lesions exhibiting large cell transformation and tumor morphology had lower CR (P=.04 and P=.035, respectively). Immunophenotype did not impact response rate (P=.23). Overall survival was significantly lower for patients with Sézary syndrome (P=.0003) and erythroderma (P 200% higher than that for single-fraction radiation. Conclusions: A single fraction of 700 cGy-800 cGy provides excellent palliation for CTCL lesions and is cost effective and convenient for the patient

  10. High dose rate brachytherapy for oral cancer

    International Nuclear Information System (INIS)

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

    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. (author)

  11. 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.

  12. High dose gamma-ray standard

    International Nuclear Information System (INIS)

    Macrin, R.; Moraru, R.

    1999-01-01

    The high gamma-ray doses produced in a gamma irradiator are used, mainly, for radiation processing, i.e. sterilization of medical products, processing of food, modifications of polymers, irradiation of electronic devices, a.s.o. The used absorbed doses depend on the application and cover the range 10 Gy to 100 MGy. The regulations in our country require that the response of the dosimetry systems, used for the irradiation of food and medical products, be calibrated and traceable to the national standards. In order to be sure that the products receive the desired absorbed dose, appropriate dosimetric measurements must be performed, including the calibration of the dosemeters and their traceability to the national standards. The high dose gamma-ray measurements are predominantly based on the use of reference radiochemical dosemeters. Among them the ferrous sulfate can be used as reference dosemeter for low doses (up to 400 Gy) but due to its characteristics it deserves to be considered a standard dosemeter and to be used for transferring the conventional absorbed dose to other chemical dosemeters used for absorbed doses up to 100 MGy. The study of the ferrous sulfate dosemeter consisted in preparing many batches of solution by different operators in quality assurance conditions and in determining for all batches the linearity, the relative intrinsic error, the repeatability and the reproducibility. The principal results are the following: the linear regression coefficient: 0.999, the relative intrinsic error: max.6 %, the repeatability (for P* = 95 %): max.3 %, the reproducibility (P* = 95%): max.5 %. (authors)

  13. Effect of single and fractionated x-irradiation on maze learning ability of mice

    International Nuclear Information System (INIS)

    Aoyama, Takashi; Norimura, Toshiyuki; Nakamura, Takeshi; Yoshikawa, Isao

    1976-01-01

    Fifty-six-day-old male ddk mice at the starting of the investigation were used as subjects through the experiment for 64 weeks. After 15 days' preliminary training, and 16 times of weekly trial training using complete maze, 15 mice received a single 224 rads of x-rays (S group), another 15 mice received two 112 rads spaced two weeks apart (F group) and another 15 mice were sham-irradiated (Control group). Then those mice were tested on the multiple T-maze with nine-choice points and change of performance was observed in terms of errorchoices by giving one test trial a week. We introduced the concept of ''confusional trials'' as an index for surmising to what extent mice failed to exhibit good maze learning habits. In the results, the F group showed significantly worse performance than the two other groups at early stages, opposite to it the S group exhibited the same, but at late stages after irradiation. The worse performance of F group should be considered to be due to the psychological after-effect to fractionated irradiation and that for S group could be assumed to be due to the acceleration of aging by the irradiation. (auth.)

  14. Surface sputtering in high-dose Fe ion implanted Si

    International Nuclear Information System (INIS)

    Ishimaru, Manabu

    2007-01-01

    Microstructures and elemental distributions in high-dose Fe ion implanted Si were characterized by means of transmission electron microscopy and Rutherford backscattering spectroscopy. Single crystalline Si(0 0 1) substrates were implanted at 350 deg. C with 120 keV Fe ions to fluences ranging from 0.1 x 10 17 to 4.0 x 10 17 /cm 2 . Extensive damage induced by ion implantation was observed inside the substrate below 1.0 x 10 17 /cm 2 , while a continuous iron silicide layer was formed at 4.0 x 10 17 /cm 2 . It was found that the spatial distribution of Fe projectiles drastically changes at the fluence between 1.0 x 10 17 and 4.0 x 10 17 /cm 2 due to surface sputtering during implantation

  15. High-dose erythropoietin in patients with progressive multiple sclerosis

    DEFF Research Database (Denmark)

    Schreiber, Karen; Magyari, Melinda; Sellebjerg, Finn

    2017-01-01

    BACKGROUND: Erythropoietin (EPO) is a part of an endogenous neuroprotective system in the brain and may address pathophysiological mechanisms in progressive multiple sclerosis (MS). OBJECTIVE: To evaluate a treatment effect of EPO on progressive MS. METHODS: This was a single-center, randomized......, double-blind, placebo-controlled phase 2 trial, in which 52 patients with secondary or primary progressive MS were allocated to treatment with recombinant EPO (48,000 IU) or placebo, administered intravenously 17 times during 24 weeks. Patients had an Expanded Disability Status Score (EDSS) from 4 to 6......: This study provides class II evidence that treatment with high-dose EPO is not an effective treatment in patients with moderately advanced progressive MS....

  16. High-dose-rate brachytherapy in uterine cervical carcinoma

    International Nuclear Information System (INIS)

    Patel, Firuza D.; Rai, Bhavana; Mallick, Indranil; Sharma, Suresh C.

    2005-01-01

    Purpose: High-dose-rate (HDR) brachytherapy is in wide use for curative treatment of cervical cancer. The American Brachytherapy Society has recommended that the individual fraction size be <7.5 Gy and the range of fractions should be four to eight; however, many fractionation schedules, varying from institution to institution, are in use. We use 9 Gy/fraction of HDR in two to five fractions in patients with carcinoma of the uterine cervix. We found that our results and toxicity were comparable to those reported in the literature and hereby present our experience with this fractionation schedule. Methods and Materials: A total of 121 patients with Stage I-III carcinoma of the uterine cervix were treated with HDR brachytherapy between 1996 and 2000. The total number of patients analyzed was 113. The median patient age was 53 years, and the histopathologic type was squamous cell carcinoma in 93% of patients. The patients were subdivided into Groups 1 and 2. In Group 1, 18 patients with Stage Ib-IIb disease, tumor size <4 cm, and preserved cervical anatomy underwent simultaneous external beam radiotherapy to the pelvis to a dose of 40 Gy in 20 fractions within 4 weeks with central shielding and HDR brachytherapy of 9 Gy/fraction, given weekly, and interdigitated with external beam radiotherapy. The 95 patients in Group 2, who had Stage IIb-IIIb disease underwent external beam radiotherapy to the pelvis to a dose of 46 Gy in 23 fractions within 4.5 weeks followed by two sessions of HDR intracavitary brachytherapy of 9 Gy each given 1 week apart. The follow-up range was 3-7 years (median, 36.4 months). Late toxicity was graded according to the Radiation Therapy Oncology Group criteria. Results: The 5-year actuarial local control and disease-free survival rate was 74.5% and 62.0%, respectively. The actuarial local control rate at 5 years was 100% for Stage I, 80% for Stage II, and 67.2% for Stage III patients. The 5-year actuarial disease-free survival rate was 88.8% for

  17. Results in patients treated with high-dose-rate interstitial brachytherapy for oral tongue cancer

    International Nuclear Information System (INIS)

    Yamamoto, Michinori; Shirane, Makoto; Ueda, Tsutomu; Miyahara, Nobuyuki

    2006-01-01

    Eight patients were treated with high-dose-rate interstitial brachytherapy for oral tongue cancer between September 2000 and August 2004. The patient distribution was 1 T1, 5 T2, 1 T3, and 1 T4a. Patients received 50-60 Gy in 10 fractions over seven days with high-dose-rate brachytherapy. Six of the eight patients were treated with a combination of external beam radiotherapy (20-30 Gy) and interstitial brachytherapy. The two-year primary local control rate was 83% for initial case. High-dose-rate brachytherapy was performed safely even for an aged person, and was a useful treatment modality for oral tongue cancer. (author)

  18. High dose rate afterloading intraluminal brachytherapy for advanced inoperable rectal carcinoma

    International Nuclear Information System (INIS)

    Hoskin, Peter J.; Canha, Sandra M. de; Bownes, Peter; Bryant, Linda; Jones, Rob Glynne

    2004-01-01

    Background and purpose: High dose rate intraluminal brachytherapy for tumours of the rectal and anal canal which were inoperable either because of the age and frailty of the patient or because of advanced disease has been evaluated. Patients and methods: In a retrospective review of 50 consecutive patients the two main indications for brachytherapy were as part of a radical radiation programme in those unfit for major surgery (26 patients) or as palliation for advanced or metastatic disease (22 patients). Radical treatment was either sole treatment delivering 6 Gy fraction 2 to 3 times weekly up to 36 Gy or as a boost of 12 Gy after 45 Gy in 25 fractions external beam chemoradiation. Palliative treatments were given predominantly as a single dose of 10 Gy. Results: This was predominantly a group of frail elderly patients with a median age of 82 years (range 35-91). Local tumour response was seen in 21/25 assessable patients with 14 complete responses. Median survival for the entire population was 6 months (range 1-54 months); in patients treated with 'radical' intent this was 25 months (range 1.5-54) and in the palliative group 7.2 months (range 1-37). The most common presenting symptom was bleeding per rectum for which a 64% response rate was obtained with 57% complete responses. Mucous discharge responded in 64% with 28% complete responses. The median duration of response was 7 months. Conclusion: Intraluminal HDR brachytherapy is an effective local treatment for patients otherwise unfit for radical surgery both as a component of radical treatment, or as a simple single palliative procedure

  19. Palliative radiation therapy for AIDS-associated Kaposi's sarcoma by using a single fraction of 800 cGy

    NARCIS (Netherlands)

    de Wit, R.; Smit, W. G.; Veenhof, K. H.; Bakker, P. J.; Oldenburger, F.; González, D. G.

    1990-01-01

    A single radiation fraction of 800 cGy was used in the treatment of acquired immunodeficiency syndrome (AIDS)-associated Kaposi's sarcoma (KS). A total of 74 radiation treatments was given to a total of 31 patients. Of all 74 evaluable treatments, there were 25 objective major responses (6 complete,

  20. Inert gases in a terra sample - Measurements in six grain-size fractions and two single particles from Lunar 20.

    Science.gov (United States)

    Heymann, D.; Lakatos, S.; Walton, J. R.

    1973-01-01

    Review of the results of inert gas measurements performed on six grain-size fractions and two single particles from four samples of Luna 20 material. Presented and discussed data include the inert gas contents, element and isotope systematics, radiation ages, and Ar-36/Ar-40 systematics.

  1. Preoperative single fraction partial breast radiotherapy for early-stage breast cancer.

    Science.gov (United States)

    Palta, Manisha; Yoo, Sua; Adamson, Justus D; Prosnitz, Leonard R; Horton, Janet K

    2012-01-01

    Several recent series evaluating external beam accelerated partial breast irradiation (PBI) have reported adverse cosmetic outcomes, possibly related to large volumes of normal tissue receiving near-prescription doses. We hypothesized that delivery of external beam PBI in a single fraction to the preoperative tumor volume would be feasible and result in a decreased dose to the uninvolved breast compared with institutional postoperative PBI historical controls. A total of 17 patients with unifocal Stage T1 breast cancer were identified. Contrast-enhanced subtraction magnetic resonance images were loaded into an Eclipse treatment planning system and used to define the target volumes. A "virtual plan" was created using four photon beams in a noncoplanar beam arrangement and optimized to deliver 15 Gy to the planning target volume. The median breast volume was 1,713 cm(3) (range: 1,014-2,140), and the median clinical target volume was 44 cm(3) (range: 26-73). In all cases, 100% of the prescription dose covered 95% of the clinical target volume. The median conformity index was 0.86 (range: 0.70-1.12). The median percentage of the ipsilateral breast volume receiving 100% and 50% of the prescribed dose was 3.8% (range: 2.2-6.9) and 13.3% (range: 7.5-20.8) compared with 18% (range: 3-42) and 53% (range: 24-65) in the institutional historical controls treated with postoperative external beam PBI (p = .002). The median maximum skin dose was 9 Gy. The median dose to 1 and 10 cm(3) of skin was 6.7 and 4.9 Gy. The doses to the heart and ipsilateral lung were negligible. Preoperative PBI resulted in a substantial reduction in ipsilateral breast tissue dose compared with postoperative PBI. The skin dose appeared reasonable, given the small volumes. A prospective Phase I trial evaluating this technique is ongoing. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Development of a simple and sensitive liquid chromatography triple quadrupole mass spectrometry (LC-MS/MS) method for the determination of cannabidiol (CBD), Δ9-tetrahydrocannabinol (THC) and its metabolites in rat whole blood after oral administration of a single high dose of CBD.

    Science.gov (United States)

    Palazzoli, Federica; Citti, Cinzia; Licata, Manuela; Vilella, Antonietta; Manca, Letizia; Zoli, Michele; Vandelli, Maria Angela; Forni, Flavio; Cannazza, Giuseppe

    2018-02-20

    The investigation of the possible conversion of cannabidiol (CBD) into Δ 9 -tetrahydrocannabinol (THC) in vivo after oral administration of CBD is reported herein since recent publications suggested a rapid conversion in simulated gastric fluid. To this end, single high dose of CBD (50mg/kg) was administered orally to rats and their blood was collected after 3 and 6h. A highly sensitive and selective LC-MS/MS method was developed and fully validated in compliance with the Scientific Working Group of Forensic Toxicology (SWGTOX) standard practices for method validation in forensic toxicology. This method also involved the optimization of cannabinoids and their metabolites extraction in order to remove co-eluting phospholipids and increase the sensitivity of the MS detection. Neither THC nor its metabolites were detected in rat whole blood after 3 or 6h from CBD administration. After oral administration, the amount of CBD dissolved in olive oil was higher than that absorbed from an ethanolic solution. This could be explained by the protection of lipid excipients towards CBD from acidic gastric juice. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Performance of thermoluminescent materials for high dose dosimetry

    International Nuclear Information System (INIS)

    Texeira, Maria I.; Cecatti, Sonia G.P.; Caldas, Linda V.E.

    2008-01-01

    Cases involving high-doses of ionizing radiation are becoming increasingly common.The objective of this work was to characterize thermoluminescent materials for the dosimetry of workers exposed to high doses. Samples of TLD-200, TLD-400 and TLD-800 pellets from Thermo Electron Corporation were studied in gamma high-doses. Dose-response curves were obtained for doses between 100 mGy and 100 Gy. The reproducibility, the lower detection limits and dose-response curves were obtained for all three materials. The different kinds of detectors show usefulness for dosimetry of workers exposed accidentally to high doses. (author)

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

    International Nuclear Information System (INIS)

    Scanderbeg, Daniel J.; Alksne, John F.; Lawson, Joshua D.; Murphy, Kevin T.

    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.

  5. 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.)

  6. Novel use of the Contura for high dose rate cranial brachytherapy.

    Science.gov (United States)

    Scanderbeg, Daniel J; Alksne, John F; Lawson, Joshua D; Murphy, Kevin T

    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. Copyright © 2011 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

  7. Urethral stricture following high dose rate brachytherapy for prostate cancer

    International Nuclear Information System (INIS)

    Sullivan, Lisa; Williams, Scott G.; Tai, Keen Hun; Foroudi, Farshad; Cleeve, L.; Duchesne, Gillian M.

    2009-01-01

    Purpose: To evaluate the incidence, timing, nature and outcome of urethral strictures following high dose rate brachytherapy (HDRB) for prostate carcinoma. Methods and materials: Data from 474 patients with clinically localised prostate cancer treated with HDRB were analysed. Ninety percent received HDRB as a boost to external beam radiotherapy (HDRBB) and the remainder as monotherapy (HDRBM). Urethral strictures were graded according to the Common Terminology Criteria for Adverse Events v3.0. Results: At a median follow-up of 41 months, 38 patients (8%) were diagnosed with a urethral stricture (6-year actuarial risk 12%). Stricture location was bulbo-membranous (BM) urethra in 92.1%. The overall actuarial rate of grade 2 or more BM urethral stricture was estimated at 10.8% (95% CI 7.0-14.9%), with a median time to diagnosis of 22 months (range 10-68 months). All strictures were initially managed with either dilatation (n = 15) or optical urethrotomy (n = 20). Second line therapy was required in 17 cases (49%), third line in three cases (9%) and 1 patient open urethroplasty (grade 3 toxicity). Predictive factors on multivariate analysis were prior trans-urethral resection of prostate (hazard ratio (HR) 2.81, 95% CI 1.15-6.85, p = 0.023); hypertension (HR 2.83, 95% CI 1.37-5.85, p = 0.005); and dose per fraction used in HDR (HR for 1 Gy increase per fraction 1.33, 95% CI 1.08-1.64, p = 0.008). Conclusions: BM urethral strictures are the most common late grade 2 or more urinary toxicity following HDR brachytherapy for prostate cancer. Most are manageable with minimally invasive procedures. Both clinical and dosimetric factors appear to influence the risk of stricture formation.

  8. Stability and Hopf Bifurcation of Fractional-Order Complex-Valued Single Neuron Model with Time Delay

    Science.gov (United States)

    Wang, Zhen; Wang, Xiaohong; Li, Yuxia; Huang, Xia

    2017-12-01

    In this paper, the problems of stability and Hopf bifurcation in a class of fractional-order complex-valued single neuron model with time delay are addressed. With the help of the stability theory of fractional-order differential equations and Laplace transforms, several new sufficient conditions, which ensure the stability of the system are derived. Taking the time delay as the bifurcation parameter, Hopf bifurcation is investigated and the critical value of the time delay for the occurrence of Hopf bifurcation is determined. Finally, two representative numerical examples are given to show the effectiveness of the theoretical results.

  9. Preoperative Single Fraction Partial Breast Radiotherapy for Early-Stage Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Palta, Manisha; Yoo, Sua; Adamson, Justus D.; Prosnitz, Leonard R. [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Horton, Janet K., E-mail: janet.horton@duke.edu [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States)

    2012-01-01

    Purpose: Several recent series evaluating external beam accelerated partial breast irradiation (PBI) have reported adverse cosmetic outcomes, possibly related to large volumes of normal tissue receiving near-prescription doses. We hypothesized that delivery of external beam PBI in a single fraction to the preoperative tumor volume would be feasible and result in a decreased dose to the uninvolved breast compared with institutional postoperative PBI historical controls. Methods and Materials: A total of 17 patients with unifocal Stage T1 breast cancer were identified. Contrast-enhanced subtraction magnetic resonance images were loaded into an Eclipse treatment planning system and used to define the target volumes. A 'virtual plan' was created using four photon beams in a noncoplanar beam arrangement and optimized to deliver 15 Gy to the planning target volume. Results: The median breast volume was 1,713 cm{sup 3} (range: 1,014-2,140), and the median clinical target volume was 44 cm{sup 3} (range: 26-73). In all cases, 100% of the prescription dose covered 95% of the clinical target volume. The median conformity index was 0.86 (range: 0.70-1.12). The median percentage of the ipsilateral breast volume receiving 100% and 50% of the prescribed dose was 3.8% (range: 2.2-6.9) and 13.3% (range: 7.5-20.8) compared with 18% (range: 3-42) and 53% (range: 24-65) in the institutional historical controls treated with postoperative external beam PBI (p = .002). The median maximum skin dose was 9 Gy. The median dose to 1 and 10 cm{sup 3} of skin was 6.7 and 4.9 Gy. The doses to the heart and ipsilateral lung were negligible. Conclusion: Preoperative PBI resulted in a substantial reduction in ipsilateral breast tissue dose compared with postoperative PBI. The skin dose appeared reasonable, given the small volumes. A prospective Phase I trial evaluating this technique is ongoing.

  10. Preoperative Single Fraction Partial Breast Radiotherapy for Early-Stage Breast Cancer

    International Nuclear Information System (INIS)

    Palta, Manisha; Yoo, Sua; Adamson, Justus D.; Prosnitz, Leonard R.; Horton, Janet K.

    2012-01-01

    Purpose: Several recent series evaluating external beam accelerated partial breast irradiation (PBI) have reported adverse cosmetic outcomes, possibly related to large volumes of normal tissue receiving near-prescription doses. We hypothesized that delivery of external beam PBI in a single fraction to the preoperative tumor volume would be feasible and result in a decreased dose to the uninvolved breast compared with institutional postoperative PBI historical controls. Methods and Materials: A total of 17 patients with unifocal Stage T1 breast cancer were identified. Contrast-enhanced subtraction magnetic resonance images were loaded into an Eclipse treatment planning system and used to define the target volumes. A “virtual plan” was created using four photon beams in a noncoplanar beam arrangement and optimized to deliver 15 Gy to the planning target volume. Results: The median breast volume was 1,713 cm 3 (range: 1,014–2,140), and the median clinical target volume was 44 cm 3 (range: 26–73). In all cases, 100% of the prescription dose covered 95% of the clinical target volume. The median conformity index was 0.86 (range: 0.70–1.12). The median percentage of the ipsilateral breast volume receiving 100% and 50% of the prescribed dose was 3.8% (range: 2.2–6.9) and 13.3% (range: 7.5–20.8) compared with 18% (range: 3–42) and 53% (range: 24–65) in the institutional historical controls treated with postoperative external beam PBI (p = .002). The median maximum skin dose was 9 Gy. The median dose to 1 and 10 cm 3 of skin was 6.7 and 4.9 Gy. The doses to the heart and ipsilateral lung were negligible. Conclusion: Preoperative PBI resulted in a substantial reduction in ipsilateral breast tissue dose compared with postoperative PBI. The skin dose appeared reasonable, given the small volumes. A prospective Phase I trial evaluating this technique is ongoing.

  11. High dose rate brachytherapy for superficial cancer of the esophagus

    International Nuclear Information System (INIS)

    Maingon, Philippe; D'Hombres, Anne; Truc, Gilles; Barillot, Isabelle; Michiels, Christophe; Bedenne, Laurent; Horiot, Jean Claude

    2000-01-01

    Purpose: We analyzed our experience with external radiotherapy, combined modality treatment, or HDR brachytherapy alone to limited esophageal cancers. Methods and Materials: From 1991 to 1996, 25 patients with limited superficial esophagus carcinomas were treated by high dose rate brachytherapy. The mean age was 63 years (43-86 years). Five patients showed superficial local recurrence after external radiotherapy. Eleven patients without invasion of the basal membrane were staged as Tis. Fourteen patients with tumors involving the submucosa without spreading to the muscle were staged as T1. Treatment consisted of HDR brachytherapy alone in 13 patients, external radiotherapy and brachytherapy in 8 cases, and concomitant chemo- and radiotherapy in 4 cases. External beam radiation was administered to a total dose of 50 Gy using 2 Gy daily fractions in 5 weeks. In cases of HDR brachytherapy alone (13 patients), 6 applications were performed once a week. Results: The mean follow-up is 31 months (range 24-96 months). Twelve patients received 2 applications and 13 patients received 6 applications. Twelve patients experienced a failure (48%), 11/12 located in the esophagus, all of them in the treated volume. One patient presented an isolated distant metastasis. In the patients treated for superficial recurrence, 4/5 were locally controlled (80%) by brachytherapy alone. After brachytherapy alone, 8/13 patients were controlled (61%). The mean disease-free survival is 14 months (1-36 months). Overall survival is 76% at 1 year, 37% at 2 years, and 14% at 3 years. Overall survival for Tis patients is 24% vs. 20% for T1 (p 0.83). Overall survival for patients treated by HDR brachytherapy alone is 43%. One patient presented with a fistula with local failure after external radiotherapy and brachytherapy. Four stenosis were registered, two were diagnosed on barium swallowing without symptoms, and two required dilatations. Conclusion: High dose rate brachytherapy permits the treating

  12. 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

  13. Pharmacogenetics and Pharmacokinetics in high-dose alkylating chemotherapy

    NARCIS (Netherlands)

    Ekhart, G.C. (Corine)

    2008-01-01

    High-dose chemotherapy in combination with peripheral blood progenitor cell transplantation has been developed as a possible curative treatment modality in several solid tumours. A frequently used high-dose regimen in the Netherlands is the CTC regimen, which is a 4-day course of cyclophosphamide,

  14. High dose rate intracavitary afterloading irradiation in malignant inoperable obturation of bile ducts

    Energy Technology Data Exchange (ETDEWEB)

    Itami, J.; Saegusa, K.; Mamiya, T.; Miyoshi, T.; Arimizu, N.; Tsuchiya, Y.; Ohto, M.

    1986-02-01

    After decompression of the bile duct with PTCD, seven patients with carcinomas of the bile ducts were submitted to an intracavitary Ir-afterloading irradiation performed according to the high-dose-rate method with a Buchler device. Most of the patients were irradiated with 30 Gy in two fractions. Five patients were also exposed to percutaneous radiation with 40 to 50 Gy. Local control was achieved in six patients. One patient developed a locoregional recurrence which was possibly due to a so-called 'geographic miss'. In one patient a benign fibrotic stenosis of the bile duct was found at the site of most intensive irradiation. Intracavitary irradiation is very important in the treatment of malignant of bile ducts. However, there is an urgent need of research with regard to the combined method with percutaneous irradiation and to the optimum fractionation of intracavitary high dose rate irradiation.

  15. High dose rate brachytherapy source measurement intercomparison.

    Science.gov (United States)

    Poder, Joel; Smith, Ryan L; Shelton, Nikki; Whitaker, May; Butler, Duncan; Haworth, Annette

    2017-06-01

    This work presents a comparison of air kerma rate (AKR) measurements performed by multiple radiotherapy centres for a single HDR 192 Ir source. Two separate groups (consisting of 15 centres) performed AKR measurements at one of two host centres in Australia. Each group travelled to one of the host centres and measured the AKR of a single 192 Ir source using their own equipment and local protocols. Results were compared to the 192 Ir source calibration certificate provided by the manufacturer by means of a ratio of measured to certified AKR. The comparisons showed remarkably consistent results with the maximum deviation in measurement from the decay-corrected source certificate value being 1.1%. The maximum percentage difference between any two measurements was less than 2%. The comparisons demonstrated the consistency of well-chambers used for 192 Ir AKR measurements in Australia, despite the lack of a local calibration service, and served as a valuable focal point for the exchange of ideas and dosimetry methods.

  16. Effect of single dose, fractionated, and hyperfractionated trunk irradiation on weight gain, respiration frequency, and survival in rats

    International Nuclear Information System (INIS)

    Kimler, B.F.; Giri, P.G.S.; Giri, U.P.; Cox, G.G.

    1986-01-01

    It is concluded that, in this rat trunk irradiation model, fractionation of a single dose into two equal doses separated by 4-6 h produced a sparing effect of approx. 5Gy as measured by delay in weight gain; approx. 4Gy as measured by increased respiration frequency; and approx. 6Gy as measured by survival. Fractionation into daily doses or hyperfractionation into twice-daily doses permitted an approximate doubling of the dose required for the same suppression of weight gain. For the respiration rates and survival endpoints, fractionation or hyperfractionation produced an even greater sparing effect since there was no increase in the respiration frequency at twice the doses that would produce changes if delivered within a few hours; and since essentially no lethality was observed at twice the doses that would kill 70%-100% of animals if delivered in one day. (UK)

  17. SU-F-T-02: Estimation of Radiobiological Doses (BED and EQD2) of Single Fraction Electronic Brachytherapy That Equivalent to I-125 Eye Plaque: By Using Linear-Quadratic and Universal Survival Curve Models

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Y; Waldron, T; Pennington, E [University Of Iowa, College of Medicine, Iowa City, IA (United States)

    2016-06-15

    Purpose: To test the radiobiological impact of hypofractionated choroidal melanoma brachytherapy, we calculated single fraction equivalent doses (SFED) of the tumor that equivalent to 85 Gy of I125-BT for 20 patients. Corresponding organs-at-risks (OARs) doses were estimated. Methods: Twenty patients treated with I125-BT were retrospectively examined. The tumor SFED values were calculated from tumor BED using a conventional linear-quadratic (L-Q) model and an universal survival curve (USC). The opposite retina (α/β = 2.58), macula (2.58), optic disc (1.75), and lens (1.2) were examined. The % doses of OARs over tumor doses were assumed to be the same as for a single fraction delivery. The OAR SFED values were converted into BED and equivalent dose in 2 Gy fraction (EQD2) by using both L-Q and USC models, then compared to I125-BT. Results: The USC-based BED and EQD2 doses of the macula, optic disc, and the lens were on average 118 ± 46% (p < 0.0527), 126 ± 43% (p < 0.0354), and 112 ± 32% (p < 0.0265) higher than those of I125-BT, respectively. The BED and EQD2 doses of the opposite retina were 52 ± 9% lower than I125-BT. The tumor SFED values were 25.2 ± 3.3 Gy and 29.1 ± 2.5 Gy when using USC and LQ models which can be delivered within 1 hour. All BED and EQD2 values using L-Q model were significantly larger when compared to the USC model (p < 0.0274) due to its large single fraction size (> 14 Gy). Conclusion: The estimated single fraction doses were feasible to be delivered within 1 hour using a high dose rate source such as electronic brachytherapy (eBT). However, the estimated OAR doses using eBT were 112 ∼ 118% higher than when using the I125-BT technique. Continued exploration of alternative dose rate or fractionation schedules should be followed.

  18. INTELLIGENT FRACTIONAL ORDER ITERATIVE LEARNING CONTROL USING FEEDBACK LINEARIZATION FOR A SINGLE-LINK ROBOT

    Directory of Open Access Journals (Sweden)

    Iman Ghasemi

    2017-05-01

    Full Text Available In this paper, iterative learning control (ILC is combined with an optimal fractional order derivative (BBO-Da-type ILC and optimal fractional and proportional-derivative (BBO-PDa-type ILC. In the update law of Arimoto's derivative iterative learning control, a first order derivative of tracking error signal is used. In the proposed method, fractional order derivative of the error signal is stated in term of 'sa' where  to update iterative learning control law. Two types of fractional order iterative learning control namely PDa-type ILC and Da-type ILC are gained for different value of a. In order to improve the performance of closed-loop control system, coefficients of both  and  learning law i.e. proportional , derivative  and  are optimized using Biogeography-Based optimization algorithm (BBO. Outcome of the simulation results are compared with those of the conventional fractional order iterative learning control to verify effectiveness of BBO-Da-type ILC and BBO-PDa-type ILC

  19. Quality control of 192Ir high dose rate after loading brachytherapy dose veracity

    International Nuclear Information System (INIS)

    Feng Zhongsu; Xu Xiao; Liu Fen

    2008-01-01

    Recently, 192 Ir high dose rate (HDR) afterloading are widely used in brachytherapy. The advantage of using HDR systems over low dose rate systems are shorter treatment time and higher fraction dose. To guarantee the veracity of the delivery dose, several quality control methods are deseribed in this work. With these we can improve the position precision, time precision and dose precision of the brachytherapy. (authors)

  20. A comparison study of steady-state vibrations with single fractional-order and distributed-order derivatives

    Directory of Open Access Journals (Sweden)

    Duan Jun-Sheng

    2017-12-01

    Full Text Available We conduct a detailed study and comparison for the one-degree-of-freedom steady-state vibrations under harmonic driving with a single fractional-order derivative and a distributed-order derivative. For each of the two vibration systems, we consider the stiffness contribution factor and damping contribution factor of the term of fractional derivatives, the amplitude and the phase difference for the response. The effects of driving frequency on these response quantities are discussed. Also the influences of the order α of the fractional derivative and the parameter γ parameterizing the weight function in the distributed-order derivative are analyzed. Two cases display similar response behaviors, but the stiffness contribution factor and damping contribution factor of the distributed-order derivative are almost monotonic change with the parameter γ, not exactly like the case of single fractional-order derivative for the order α. The case of the distributed-order derivative provides us more options for the weight function and parameters.

  1. Chromosome aberrations of the peripheral lymphocytes in rabbits exposed to single and fractionated whole-body x-irradiations

    International Nuclear Information System (INIS)

    Tamura, Hiroaki; Sakurai, Masaharu; Sugahara, Tsutomu.

    1978-01-01

    The changes in the frequency of peripheral lymphocytes with chromosome aberrations were observed during or after irradiation of rabbits exposed to fractionated or single whole-body irradiations. In rabbits given daily fractionated whole-body irradiations the incidence of the aberrations showed a linear increase in the first week; however, the incidence decreased thereafter though exposures were repeated. The lymphocyte count tended to decrease as the number of irradiations increased. In rabbits exposed to a single dose of 250 R or 500 R the incidence of aberrations rapidly decreased over a period of 10 days following irradiation, and then showed a little change thereafter. The lymphocyte count in the peripheral blood reached a nadir 2 - 5 days after irradiation, and then started to increase gradually. It was speculated that there are two types of lymphocytes, long-lived and short-lived, in the peripheral blood of rabbits, both of which are PHA-committed. (auth.)

  2. Treatment of carcinoma of uterine cervix with high-dose-rate intracavitary irradiation using Ralstron

    International Nuclear Information System (INIS)

    Suh, C.O.; Kim, G.E.; Loh, J.J.K.

    1988-01-01

    From May 1979 through December 1981, a total of 530 patients with carcinoma of the uterine cervix were treated with radiation therapy with curative intent. Of the 530 patients, 365 were treated with a high-dose-rate remote-controlled afterloading system (RALS) using a cobalt source, and 165 patients received a low dose rate using a radium source. External pelvic irradiation with a total of 40-50 Gy to the whole pelvis followed by intracavitary radiation (ICR) with a total dose of 30-39 Gy in ten to 13 fractions to point A was the treatment protocol. ICR was given three times a week with a dose of 3 Gy per fraction. Five-year actuarial survival rate with high-dose-rate ICR by stage was as follows: stage I:82.7% (N = 19) stage II:69.6% (N = 184), and stage III:52.2% (N = 156). The above results were comparable with those with conventional low-dose-rate ICR treatment, and late complications were far less. The application of high-dose-rate ICR was technically simple and easily performed on an outpatient basis without anesthesia, and the patients tolerated it very well. Radiation exposure to personnel was virtually none as compared with that of low-dose-rate ICR. Within a given period of time, more patients can be treated with high-dose-rate ICR because of the short treatment time. The authors therefore conclude that high-dose-rate ICR is suitable for a cancer center where a large number of patients are to be treated

  3. High-dose gadolinium-enhanced MRI for diagnosis of meningeal metastases

    International Nuclear Information System (INIS)

    Kallmes, D.F.; Gray, L.; Glass, J.P.

    1998-01-01

    We compared high-dose (0.3 mmol/kg) and standard-dose (0.1 mmol/kg) gadolinium-enhanced MRI for diagnosis of meningeal metastases in 12 patients with suspected meningeal metastases. They were imaged with both standard-dose and high-dose gadolinium. All patients with abnormal meningeal enhancement underwent at least one lumbar puncture for cerebrospinal fluid (CSF) cytology, while patients with normal meningeal enhancement were followed clinically. All patients with negative CSF cytology also were followed clinically. A single observer reviewed all the images, with specific attention to the enhancement pattern of the meninges. Abnormal leptomeningeal enhancement was present in three cases, and abnormal pachymeningeal enhancement in three other patients. All of these patients had abnormal CSF analyses. In two of the three cases of abnormal leptomeningeal enhancement the disease was more evident on high-dose than on standard-dose imaging; in one case the abnormal enhancement was visible only on high-dose imaging. In one of the three cases with abnormal pachymeningeal enhancement, the disease was evident prospectively only with high-dose imaging. (orig.)

  4. 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

  5. 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.

  6. Copenhagen's single system premise prevents a unified view of integer and fractional quantum Hall effect

    CERN Document Server

    Post, E J

    1999-01-01

    This essay presents conclusive evidence of the impermissibility of Copenhagen's single system interpretation of the Schroedinger process. The latter needs to be viewed as a tool exclusively describing phase and orientation randomized ensembles and is not be used for isolated single systems. Asymptotic closeness of single system and ensemble behavior and the rare nature of true single system manifestations have prevented a definitive identification of this Copenhagen deficiency over the past three quarter century. Quantum uncertainty so becomes a basic trade mark of phase and orientation disordered ensembles. The ensuing void of usable single system tools opens a new inquiry for tools without statistical connotations. Three, in part already known, period integrals here identified as flux, charge and action counters emerge as diffeo-4 invariant tools fully compatible with the demands of the general theory of relativity. The discovery of the quantum Hall effect has been instrumental in forcing a distinction betw...

  7. Enhanced Peptide Detection Toward Single-Neuron Proteomics by Reversed-Phase Fractionation Capillary Electrophoresis Mass Spectrometry

    Science.gov (United States)

    Choi, Sam B.; Lombard-Banek, Camille; Muñoz-LLancao, Pablo; Manzini, M. Chiara; Nemes, Peter

    2018-05-01

    The ability to detect peptides and proteins in single cells is vital for understanding cell heterogeneity in the nervous system. Capillary electrophoresis (CE) nanoelectrospray ionization (nanoESI) provides high-resolution mass spectrometry (HRMS) with trace-level sensitivity, but compressed separation during CE challenges protein identification by tandem HRMS with limited MS/MS duty cycle. Here, we supplemented ultrasensitive CE-nanoESI-HRMS with reversed-phase (RP) fractionation to enhance identifications from protein digest amounts that approximate to a few mammalian neurons. An 1 to 20 μg neuronal protein digest was fractionated on a RP column (ZipTip), and 1 ng to 500 pg of peptides were analyzed by a custom-built CE-HRMS system. Compared with the control (no fractionation), RP fractionation improved CE separation (theoretical plates 274,000 versus 412,000 maximum, resp.), which enhanced detection sensitivity (2.5-fold higher signal-to-noise ratio), minimized co-isolation spectral interferences during MS/MS, and increased the temporal rate of peptide identification by up to 57%. From 1 ng of protein digest (organization. [Figure not available: see fulltext.

  8. Long-term Nasal and Peri-oral Tightening by a Single Fractional Noninsulated Microneedle Radiofrequency Treatment.

    Science.gov (United States)

    Tanaka, Yohei

    2017-02-01

    Background: The skin tightening effects induced by non-insulated microneedle radiofrequency have proved long-lasting. Our previous three-dimensional volumetric assessment showed significant facial tightening for up to six months. However, nasal and peri-oral tightening effects lasted longer. The objective of this study was to investigate the distribution of the long-term volumetric reduction in facial area induced by a single fractional non-insulated microneedle radiofrequency treatment. Methods: Fifteen Asian patients underwent full facial skin tightening using a sharply tapered non-insulated microneedle radiofrequency applicator with a novel fractionated pulse mode. Three-dimensional volumetric assessments were performed at six and 12 months post-treatment. Patients rated their satisfaction using a 5-point scale at each follow up. Results: Objective assessments with superimposed three-dimensional color images showed significant volumetric reduction in the nasal and peri-oral areas at 12 months post-treatment in all patients. Median volumetric reductions at six and 12 months post-treatment were 13.1 and 12.3ml, respectively. All of the patients were satisfied with their results 12 months post-treatment. Side effects were not observed. Conclusions: This single fractional NIMNRF treatment provided long-lasting nasal and peri-oral tightening as shown via 3D volumetric assessment. Moreover, NIMNRF produced minimal complications, downtime, and few side effects. This approach provides safe and effective treatment of skin tightening.

  9. 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

  10. Treatment of the prostate cancer with high dose rate brachytherapy

    International Nuclear Information System (INIS)

    Martinez, Alvaro; Torres Silva, Felipe

    2002-01-01

    The prostate cancer treatment in early stages is controversial. The high dose rate brachytherapy has been used like monotherapy or boost with external beam radiotherapy in advanced disease. This paper describes the technique and the advantages over other modalities

  11. High-dose dosimetry using natural silicate minerals

    International Nuclear Information System (INIS)

    Carmo, Lucas S. do; Mendes, Leticia; Watanabe, Shigueo; Rao, Gundu; Lucas, Natasha; Sato, Karina; Barbosa, Renata F.

    2015-01-01

    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)

  12. 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)

  13. Dose rate and fractionation: Relative importance in radiation for bone marrow transplantation

    International Nuclear Information System (INIS)

    Tarbell, N.J.; Rosenblatt, M.; Mauch, P.; Hellman, S.

    1987-01-01

    The optimal dose rate and fractionation schedules for total body irradiation (TBI) in bone marrow transplantation (BMT) are presently unknown. This study compares several fractionation and dose rate schedules that are currently in clinical use. C/sub 3/H/HeJ were given TBI and the bone marrow survival fraction was calculated using the CFU's assay. Irradiation was given as low dose rate (LDR) at 5 cGy/min or high dose rate (HDR) at 80 cGy/min, in single fraction (SF) and fractionated (FX) regimens. These results indicate no increase in survival for the normal bone marrow stem cells with fractionation either at high or low dose-rates. In fact, fractionation seemed to decrease the bone marrow survival over single fraction radiation

  14. One- vs. Three-Fraction Pancreatic Stereotactic Body Radiation Therapy for Pancreatic Carcinoma: Single Institution Retrospective Review

    Directory of Open Access Journals (Sweden)

    Philip Anthony Sutera

    2017-11-01

    Full Text Available Background/introductionEarly reports of stereotactic body radiation therapy (SBRT for pancreatic ductal adenocarcinoma (PDAC used single fraction, but eventually shifted to multifraction regimens. We conducted a single institution review of our patients treated with single- or multifraction SBRT to determine whether any outcome differences existed.Methods and materialsPatients treated with SBRT in any setting for PDAC at our facility were included, from 2004 to 2014. Overall survival (OS, local control (LC, regional control (RC, distant metastasis (DM, and late grade 3 or greater radiation toxicities from the time of SBRT were calculated using Kaplan–Meier estimation to either the date of last follow-up/death or local/regional/distant failure.ResultsWe identified 289 patients (291 lesions with pathologically confirmed PDAC. Median age was 69 (range, 33–90 years. Median gross tumor volume was 12.3 (8.6–21.3 cm3 and planning target volume 17.9 (12–27 cm3. Single fraction was used in 90 (30.9% and multifraction in 201 (69.1% lesions. At a median follow-up of 17.3 months (IQR 10.1–29.3 months, the median survival for the entire cohort 17.8 months with a 2-year OS of 35.3%. Univariate analysis showed multifraction schemes to have a higher 2-year OS 30.5% vs. 37.5% (p = 0.019, it did not hold significance on MVA. Multifractionation schemes were found to have a higher LC on MVA (HR = 0.53, 95% CI, 0.33–0.85, p = 0.009. At 2 years, late grade 3+ toxicity was 2.5%. Post-SBRT CA19-9 was found on MVA to be a prognostic factor for OS (HR = 1.01, 95% CI, 1.01–1.01, p = 0.009, RC (HR = 1.01, 95% CI 1.01–1.01, p = 0.02, and DM (HR = 1.01, 95% CI, 1.01–1.01, p = 0.001.ConclusionOur single institution retrospective review is the largest to date comparing single and multifraction SBRT and the first to show multifraction regimen SBRT to have a higher LC than single fractionation. Additionally, we

  15. Base of skull and cervical spine chordomas in children treated by high-dose irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Benk, Veronique; Liebsch, Norbert J; Munzenrider, John E; Efird, John; McManus, Patricia; Suit, Herman

    1995-02-01

    Purpose: To evaluate the outcome of children with base of skull or cervical spine chordomas treated by high dose irradiation. Methods and Materials: Eighteen children, 4 to 18 years of age, with base of skull or cervical spine chordomas, received fractionated high-dose postoperative radiation using mixed photon and 160 MeV proton beams. The median tumor dose was 69 Cobalt Gray-equivalent (CGE) with a 1.8 CGE daily fraction. Results: The median follow-up was 72 months. The 5-year actuarial survival was 68% and the 5-year disease-free survival (DFS) was 63%. The only significant prognostic factor was the location: patients with cervical spine chordomas had a worse survival than those with base of skull lesions (p = 0.008). The incidence of treatment-related morbidity was acceptable: two patients developed a growth hormone deficit corrected by hormone replacement, one temporal lobe necrosis, and one fibrosis of the temporalis muscle, improved by surgery. Conclusion: Chordomas in children behave similarly to those in adults: children can receive the same high-dose irradiation as adults with acceptable morbidity.

  16. Base of skull and cervical spine chordomas in children treated by high-dose irradiation

    International Nuclear Information System (INIS)

    Benk, Veronique; Liebsch, Norbert J.; Munzenrider, John E.; Efird, John; McManus, Patricia; Suit, Herman

    1995-01-01

    Purpose: To evaluate the outcome of children with base of skull or cervical spine chordomas treated by high dose irradiation. Methods and Materials: Eighteen children, 4 to 18 years of age, with base of skull or cervical spine chordomas, received fractionated high-dose postoperative radiation using mixed photon and 160 MeV proton beams. The median tumor dose was 69 Cobalt Gray-equivalent (CGE) with a 1.8 CGE daily fraction. Results: The median follow-up was 72 months. The 5-year actuarial survival was 68% and the 5-year disease-free survival (DFS) was 63%. The only significant prognostic factor was the location: patients with cervical spine chordomas had a worse survival than those with base of skull lesions (p = 0.008). The incidence of treatment-related morbidity was acceptable: two patients developed a growth hormone deficit corrected by hormone replacement, one temporal lobe necrosis, and one fibrosis of the temporalis muscle, improved by surgery. Conclusion: Chordomas in children behave similarly to those in adults: children can receive the same high-dose irradiation as adults with acceptable morbidity

  17. Three independent one-dimensional margins for single-fraction frameless stereotactic radiosurgery brain cases using CBCT

    International Nuclear Information System (INIS)

    Zhang, Qinghui; Chan, Maria F.; Burman, Chandra; Song, Yulin; Zhang, Mutian

    2013-01-01

    Purpose: Setting a proper margin is crucial for not only delivering the required radiation dose to a target volume, but also reducing the unnecessary radiation to the adjacent organs at risk. This study investigated the independent one-dimensional symmetric and asymmetric margins between the clinical target volume (CTV) and the planning target volume (PTV) for linac-based single-fraction frameless stereotactic radiosurgery (SRS).Methods: The authors assumed a Dirac delta function for the systematic error of a specific machine and a Gaussian function for the residual setup errors. Margin formulas were then derived in details to arrive at a suitable CTV-to-PTV margin for single-fraction frameless SRS. Such a margin ensured that the CTV would receive the prescribed dose in 95% of the patients. To validate our margin formalism, the authors retrospectively analyzed nine patients who were previously treated with noncoplanar conformal beams. Cone-beam computed tomography (CBCT) was used in the patient setup. The isocenter shifts between the CBCT and linac were measured for a Varian Trilogy linear accelerator for three months. For each plan, the authors shifted the isocenter of the plan in each direction by ±3 mm simultaneously to simulate the worst setup scenario. Subsequently, the asymptotic behavior of the CTV V 80% for each patient was studied as the setup error approached the CTV-PTV margin.Results: The authors found that the proper margin for single-fraction frameless SRS cases with brain cancer was about 3 mm for the machine investigated in this study. The isocenter shifts between the CBCT and the linac remained almost constant over a period of three months for this specific machine. This confirmed our assumption that the machine systematic error distribution could be approximated as a delta function. This definition is especially relevant to a single-fraction treatment. The prescribed dose coverage for all the patients investigated was 96.1%± 5.5% with an extreme

  18. A real-time in vivo dosimetric verification method for high-dose rate intracavitary brachytherapy of nasopharyngeal carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Qi Zhenyu; Deng Xiaowu; Cao Xinping; Huang Shaomin; Lerch, Michael; Rosenfeld, Anatoly [State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou 510060 (China) and Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522 (Australia); State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou 510060 (China); Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522 (Australia)

    2012-11-15

    Purpose: A real-time in vivo dosimetric verification method using metal-oxide-semiconductor field effect transistor (MOSFET) dosimeters has been developed for patient dosimetry in high-dose rate (HDR) intracavitary brachytherapy of nasopharyngeal carcinoma (NPC). Methods: The necessary calibration and correction factors for MOSFET measurements in {sup 192}Iridium source were determined in a water phantom. With the detector placed inside a custom-made nasopharyngeal applicator, the actual dose delivered to the tumor was measured in vivo and compared to the calculated values using a commercial brachytherapy planning system. Results: Five MOSFETs were independently calibrated with the HDR source, yielding calibration factors of 0.48 {+-} 0.007 cGy/mV. The maximum sensitivity variation was no more than 7% in the clinically relevant distance range of 1-5 cm from the source. A total of 70 in vivo measurements in 11 NPC patients demonstrated good agreement with the treatment planning. The mean differences between the planned and the actually delivered dose within a single treatment fraction were -0.1%{+-} 3.8% and -0.1%{+-} 3.7%, respectively, for right and left side assessments. The maximum dose deviation was less than 8.5%. Conclusions: In vivo measurement using the real-time MOSFET dosimetry system is possible to evaluate the actual dose to the tumor received by the patient during a treatment fraction and thus can offer another line of security to detect and prevent large errors.

  19. Trapping a single atom with a fraction of a photon using a photonic crystal nanocavity

    NARCIS (Netherlands)

    van Oosten, D.; Kuipers, L.

    2011-01-01

    We consider the interaction between a single rubidium atom and a photonic crystal nanocavity. Because of the ultrasmall mode volume of the nanocavity, an extremely strong coupling regime can be achieved in which the atom can shift the cavity resonance by many cavity linewidths. We show that this

  20. Increasing amperometric biosensor sensitivity by length fractionated single-walled carbon nanotubes

    DEFF Research Database (Denmark)

    Tasca, Federico; Gorton, Lo; Wagner, Jakob Birkedal

    2008-01-01

    In this work the sensitivity-increasing effect of single-walled carbon nanotubes (SWCNTs) in amperometric biosensors, depending on their average length distribution, was studied. For this purpose the SWCNTs were oxidatively shortened and subsequently length separated by size exclusion...

  1. 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.

  2. Determination of a cross-sectional void fraction in a tube bundle using a single beam gamma densitometer

    International Nuclear Information System (INIS)

    Guichard, J.; Mezoul, B.; Peturaud, P.; Thomas, B.

    1991-06-01

    In order to qualify 3-dimensional two-phase flow computer codes modelling average flows in tube bundles, cross-section average void fractions must be measured over sub-channels. On the VATICAN mockup, such void fractions(integrated on the mockup thickness) are determined using a single (narrow) beam gamma densitometer. But to avoid a refined exploration of each measurement mesh, for each test, empirical calibration curves have been developed in a regular mesh of the mockup, in axial flow conditions. These calibration curves, which evaluate the sought cross-sectional value as a function of a chordal void fraction (right in the inter-rod gap) depend only on heat flux density and pressure. The data are consistent with the ARMAND-MASSENA and LELLOUCHE-ZOLOTAR slip correlations, and they are fitted by 3rd degree polynomials, for each heat flux density investigated, with a good accuracy. Unfortunately, preliminary testing and analysis indicate that the use of these calibration curves in subcooled boiling and transverse mixing zones might result in significant uncertainties and errors

  3. Outcomes and Toxicity for Hypofractionated and Single-Fraction Image-Guided Stereotactic Radiosurgery for Sarcomas Metastasizing to the Spine

    Energy Technology Data Exchange (ETDEWEB)

    Folkert, Michael R. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Bilsky, Mark H. [Department of Neurosurgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Tom, Ashlyn K. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Oh, Jung Hun [Department of Medical Physics, 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); Laufer, Ilya [Department of Neurosurgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Tap, William D. [Department of Medical Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Yamada, Yoshiya, E-mail: yamadaj@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

    2014-04-01

    Purpose: Conventional radiation treatment (20-40 Gy in 5-20 fractions, 2-5 Gy per fraction) for sarcoma metastatic to the spine provides subtherapeutic doses, resulting in poor durable local control (LC) (50%-77% at 1 year). Hypofractionated (HF) and/or single-fraction (SF) image-guided stereotactic radiosurgery (IG-SRS) may provide a more effective means of managing these lesions. Methods and Materials: Patients with pathologically proven high-grade sarcoma metastatic to the spine treated with HF and SF IG-SRS were included. LC and overall survival (OS) were analyzed by the use of Kaplan-Meier statistics. Univariate and multivariate analyses were performed by the use of Cox regression with competing-risks analysis; all confidence intervals are 95%. Toxicities were assessed according to Common Terminology Criteria for Adverse Events, version 4.0. Results: From May 2005 to November 11, 2012, 88 patients with 120 discrete metastases received HF (3-6 fractions; median dose, 28.5 Gy; n=52, 43.3%) or SF IG-SRS (median dose, 24 Gy; n=68, 56.7%). The median follow-up time was 12.3 months. At 12 months, LC was 87.9% (confidence interval [CI], 81.3%-94.5%), OS was 60.6% (CI, 49.6%-71.6%), and median survival was 16.9 months. SF IG-SRS demonstrated superior LC to HF IG-SRS (12-month LC of 90.8% [CI, 83%-98.6%] vs 84.1% [CI, 72.9%-95.3%] P=.007) and retained significance on multivariate analysis (P=.030, hazard ratio 0.345; CI, 0.132-0.901]. Treatment was well tolerated, with 1% acute grade 3 toxicity, 4.5% chronic grade 3 toxicity, and no grade >3 toxicities. Conclusions: In the largest series of metastatic sarcoma to the spine to date, IG-SRS provides excellent LC in the setting of an aggressive disease with low radiation sensitivity and poor prognosis. Single-fraction IG-SRS is associated with the highest rates of LC with minimal toxicity.

  4. SU-E-T-480: Radiobiological Dose Comparison of Single Fraction SRS, Multi-Fraction SRT and Multi-Stage SRS of Large Target Volumes Using the Linear-Quadratic Formula

    International Nuclear Information System (INIS)

    Ding, C; Hrycushko, B; Jiang, S; Meyer, J; Timmerman, R

    2014-01-01

    Purpose: To compare the radiobiological effect on large tumors and surrounding normal tissues from single fraction SRS, multi-fractionated SRT, and multi-staged SRS treatment. Methods: An anthropomorphic head phantom with a centrally located large volume target (18.2 cm 3 ) was scanned using a 16 slice large bore CT simulator. Scans were imported to the Multiplan treatment planning system where a total prescription dose of 20Gy was used for a single, three staged and three fractionated treatment. Cyber Knife treatment plans were inversely optimized for the target volume to achieve at least 95% coverage of the prescription dose. For the multistage plan, the target was segmented into three subtargets having similar volume and shape. Staged plans for individual subtargets were generated based on a planning technique where the beam MUs of the original plan on the total target volume are changed by weighting the MUs based on projected beam lengths within each subtarget. Dose matrices for each plan were export in DICOM format and used to calculate equivalent dose distributions in 2Gy fractions using an alpha beta ratio of 10 for the target and 3 for normal tissue. Results: Singe fraction SRS, multi-stage plan and multi-fractionated SRT plans had an average 2Gy dose equivalent to the target of 62.89Gy, 37.91Gy and 33.68Gy, respectively. The normal tissue within 12Gy physical dose region had an average 2Gy dose equivalent of 29.55Gy, 16.08Gy and 13.93Gy, respectively. Conclusion: The single fraction SRS plan had the largest predicted biological effect for the target and the surrounding normal tissue. The multi-stage treatment provided for a more potent biologically effect on target compared to the multi-fraction SRT treatments with less biological normal tissue than single-fraction SRS treatment

  5. Cost-Effectiveness Analysis of Single Fraction of Stereotactic Body Radiation Therapy Compared With Single Fraction of External Beam Radiation Therapy for Palliation of Vertebral Bone Metastases

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hayeon, E-mail: kimh2@upmc.edu [Department of Radiation Oncology, University of Pittsburgh Cancer Institute, Pittsburgh, Pennsylvania (United States); Rajagopalan, Malolan S.; Beriwal, Sushil; Huq, M. Saiful [Department of Radiation Oncology, University of Pittsburgh Cancer Institute, Pittsburgh, Pennsylvania (United States); Smith, Kenneth J. [Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania (United States)

    2015-03-01

    Purpose: Stereotactic body radiation therapy (SBRT) has been proposed for the palliation of painful vertebral bone metastases because higher radiation doses may result in superior and more durable pain control. A phase III clinical trial (Radiation Therapy Oncology Group 0631) comparing single fraction SBRT with single fraction external beam radiation therapy (EBRT) in palliative treatment of painful vertebral bone metastases is now ongoing. We performed a cost-effectiveness analysis to compare these strategies. Methods and Materials: A Markov model, using a 1-month cycle over a lifetime horizon, was developed to compare the cost-effectiveness of SBRT (16 or 18 Gy in 1 fraction) with that of 8 Gy in 1 fraction of EBRT. Transition probabilities, quality of life utilities, and costs associated with SBRT and EBRT were captured in the model. Costs were based on Medicare reimbursement in 2014. Strategies were compared using the incremental cost-effectiveness ratio (ICER), and effectiveness was measured in quality-adjusted life years (QALYs). To account for uncertainty, 1-way, 2-way and probabilistic sensitivity analyses were performed. Strategies were evaluated with a willingness-to-pay (WTP) threshold of $100,000 per QALY gained. Results: Base case pain relief after the treatment was assumed as 20% higher in SBRT. Base case treatment costs for SBRT and EBRT were $9000 and $1087, respectively. In the base case analysis, SBRT resulted in an ICER of $124,552 per QALY gained. In 1-way sensitivity analyses, results were most sensitive to variation of the utility of unrelieved pain; the utility of relieved pain after initial treatment and median survival were also sensitive to variation. If median survival is ≥11 months, SBRT cost <$100,000 per QALY gained. Conclusion: SBRT for palliation of vertebral bone metastases is not cost-effective compared with EBRT at a $100,000 per QALY gained WTP threshold. However, if median survival is ≥11 months, SBRT costs ≤$100

  6. Cost-Effectiveness Analysis of Single Fraction of Stereotactic Body Radiation Therapy Compared With Single Fraction of External Beam Radiation Therapy for Palliation of Vertebral Bone Metastases

    International Nuclear Information System (INIS)

    Kim, Hayeon; Rajagopalan, Malolan S.; Beriwal, Sushil; Huq, M. Saiful; Smith, Kenneth J.

    2015-01-01

    Purpose: Stereotactic body radiation therapy (SBRT) has been proposed for the palliation of painful vertebral bone metastases because higher radiation doses may result in superior and more durable pain control. A phase III clinical trial (Radiation Therapy Oncology Group 0631) comparing single fraction SBRT with single fraction external beam radiation therapy (EBRT) in palliative treatment of painful vertebral bone metastases is now ongoing. We performed a cost-effectiveness analysis to compare these strategies. Methods and Materials: A Markov model, using a 1-month cycle over a lifetime horizon, was developed to compare the cost-effectiveness of SBRT (16 or 18 Gy in 1 fraction) with that of 8 Gy in 1 fraction of EBRT. Transition probabilities, quality of life utilities, and costs associated with SBRT and EBRT were captured in the model. Costs were based on Medicare reimbursement in 2014. Strategies were compared using the incremental cost-effectiveness ratio (ICER), and effectiveness was measured in quality-adjusted life years (QALYs). To account for uncertainty, 1-way, 2-way and probabilistic sensitivity analyses were performed. Strategies were evaluated with a willingness-to-pay (WTP) threshold of $100,000 per QALY gained. Results: Base case pain relief after the treatment was assumed as 20% higher in SBRT. Base case treatment costs for SBRT and EBRT were $9000 and $1087, respectively. In the base case analysis, SBRT resulted in an ICER of $124,552 per QALY gained. In 1-way sensitivity analyses, results were most sensitive to variation of the utility of unrelieved pain; the utility of relieved pain after initial treatment and median survival were also sensitive to variation. If median survival is ≥11 months, SBRT cost <$100,000 per QALY gained. Conclusion: SBRT for palliation of vertebral bone metastases is not cost-effective compared with EBRT at a $100,000 per QALY gained WTP threshold. However, if median survival is ≥11 months, SBRT costs ≤$100

  7. Assessment of National Practice for Palliative Radiation Therapy for Bone Metastases Suggests Marked Underutilization of Single-Fraction Regimens in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Rutter, Charles E., E-mail: charles.rutter@yale.edu [Department of Therapeutic Radiology, Yale School of Medicine, New Haven, Connecticut (United States); Yale Cancer Center, New Haven, Connecticut (United States); Yu, James B.; Wilson, Lynn D.; Park, Henry S. [Department of Therapeutic Radiology, Yale School of Medicine, New Haven, Connecticut (United States); Yale Cancer Center, New Haven, Connecticut (United States)

    2015-03-01

    Purpose: To characterize temporal trends in the application of various bone metastasis fractionations within the United States during the past decade, using the National Cancer Data Base; the primary aim was to determine whether clinical practice in the United States has changed over time to reflect the published randomized evidence and the growing movement for value-based treatment decisions. Patients and Methods: The National Cancer Data Base was used to identify patients treated to osseous metastases from breast, prostate, and lung cancer. Utilization of single-fraction versus multiple-fraction radiation therapy was compared according to demographic, disease-related, and health care system details. Results: We included 24,992 patients treated during the period 2005-2011 for bone metastases. Among patients treated to non-spinal/vertebral sites (n=9011), 4.7% received 8 Gy in 1 fraction, whereas 95.3% received multiple-fraction treatment. Over time the proportion of patients receiving a single fraction of 8 Gy increased (from 3.4% in 2005 to 7.5% in 2011). Numerous independent predictors of single-fraction treatment were identified, including older age, farther travel distance for treatment, academic treatment facility, and non-private health insurance (P<.05). Conclusions: Single-fraction palliative radiation therapy regimens are significantly underutilized in current practice in the United States. Further efforts are needed to address this issue, such that evidence-based and cost-conscious care becomes more commonplace.

  8. Epithelial regeneration of transposed intestine after high doses of X irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Both, N.J. de; Vermey, M [Erasmus Universiteit, Rotterdam (Netherlands)

    1976-01-01

    The regeneration capacities of normal and transposed small bowel epithelium were compared in rats after applying high doses of x irradiation. It has been shown that the potency of the mucosa to regenerate was much higher than assumed and that the mucosa could regenerate after single doses varying from 2000 to 5000 R. Even in the villus epithelium and in flat epithelium covering infiltrates of the lamina propria cells survived, which were still able to resume proliferative activity several days after irradiation.

  9. Implementation of high-dose chemical dosimetry for industrial facilities

    International Nuclear Information System (INIS)

    Conceicao, Cirilo Cezar Sant'Anna da

    2006-01-01

    The purpose of this work is the implementation of methodology for high dose measurements using chemical dosimeters in liquid phase, traceable to the international metrology system, and make available in the country, the standard of high-dose to industrial irradiation facilities and research irradiators, trough the quality program with comparative measurements and direct use of the standard dosimeters in routine. The use of these low cost dosimetry systems in industrial irradiation facilities, assists to the certification requirements and it can reduce the costs with dosimetry for approximately 20% of the total dosimetry costs, using these systems in routine measurements and validation process, largely substituting the imported PMMA dosimeters, among others. (author)

  10. Statistical behavior of high doses in medical radiodiagnosis

    International Nuclear Information System (INIS)

    Barboza, Adriana Elisa

    2014-01-01

    This work has as main purpose statistically estimating occupational exposure in medical diagnostic radiology in cases of high doses recorded in 2011 at national level. For statistical survey of this study, doses of 372 IOE's diagnostic radiology in different Brazilian states were evaluated. Data were extracted from the work of monograph (Research Methodology Of High Doses In Medical Radiodiagnostic) that contains the database's information Sector Management doses of IRD/CNEN-RJ, Brazil. The identification of these states allows the Sanitary Surveillance (VISA) responsible, becomes aware of events and work with programs to reduce these events. (author)

  11. Study of teflon pads as high doses dosemeters

    International Nuclear Information System (INIS)

    Teixeira, Maria Ines; Caldas, Linda V.E.

    2013-01-01

    The aim of this work is to study the Teflon, which is used as a binder in the manufacture of dosimetric tablets, for the feasibility of this material as high dose dosemeter. In this paper we used the technique of thermally stimulated luminescence (OSL) to characterize the dosimetric properties of Teflon. Teflon samples were exposed to different doses of radiation, using a source of gamma radiation ( 60 Co). It was obtained dose-response curve between 100 Gy to 50 kGy and reproducibility of OSL response. The preliminary results show that Teflon is a useful material to high dose dosimetry

  12. Single-Fraction Stereotactic Body Radiation Therapy and Sequential Gemcitabine for the Treatment of Locally Advanced Pancreatic Cancer

    International Nuclear Information System (INIS)

    Schellenberg, Devin; Kim, Jeff; Christman-Skieller, Claudia; Chun, Carlene L.; Columbo, Laurie Ann; Ford, James M.; Fisher, George A.; Kunz, Pamela L.; Van Dam, Jacques; Quon, Andrew; Desser, Terry S.; Norton, Jeffrey; Hsu, Annie; Maxim, Peter G.; Xing, Lei; Goodman, Karyn A.; Chang, Daniel T.; Koong, Albert C.

    2011-01-01

    Purpose: This Phase II trial evaluated the toxicity, local control, and overall survival in patients treated with sequential gemcitabine and linear accelerator-based single-fraction stereotactic body radiotherapy (SBRT). Methods and Materials: Twenty patients with locally advanced, nonmetastatic pancreatic adenocarcinoma were enrolled on this prospective single-institution, institutional review board-approved study. Gemcitabine was administered on Days 1, 8, and 15, and SBRT on Day 29. Gemcitabine was restarted on Day 43 and continued for 3-5 cycles. SBRT of 25 Gy in a single fraction was delivered to the internal target volume with a 2- 3-mm margin using a nine-field intensity-modulated radiotherapy technique. Respiratory gating was used to account for breathing motion. Follow-up evaluations occurred at 4-6 weeks, 10-12 weeks, and every 3 months after SBRT. Results: All patients completed SBRT and a median of five cycles of chemotherapy. Follow-up for the 2 remaining alive patients was 25.1 and 36.4 months. No acute Grade 3 or greater nonhematologic toxicity was observed. Late Grade 3 or greater toxicities occurred in 1 patient (5%) and consisted of a duodenal perforation (G4). Three patients (15%) developed ulcers (G2) that were medically managed. Overall, median survival was 11.8 months, with 1-year survival of 50% and 2-year survival of 20%. Using serial computed tomography, the freedom from local progression was 94% at 1 year. Conclusion: Linear accelerator-delivered SBRT with sequential gemcitabine resulted in excellent local control of locally advanced pancreatic cancer. Future studies will address strategies for reducing long-term duodenal toxicity associated with SBRT.

  13. Cosmetic results in early stage breast cancer patients with high-dose brachytherapy after conservative surgery

    International Nuclear Information System (INIS)

    Torres, Felipe; Pineda, Beatriz E

    2004-01-01

    Purpose: to reveal cosmetic results in patients at early stages of low risk breast cancer treated with partial accelerated radiotherapy using high dose rate brachytherapy. Methods and materials: from March 2001 to July 2003,14 stages l and ll breast cancer patients were treated at the Colombian national cancer institute in Bogota with conservative surgery and radiotherapy upon the tumor bed (partial accelerated radiotherapy), using interstitial implants with iridium 192 (high dose rate brachytherapy) with a dose of 32 Gys, over 4 days, at 8 fractions twice a day. Results: with an average follow up of 17.7 months, good cosmetic results were found among 71.4 % of patients and excellent results among 14.3% of patients, furthermore none of the patients neither local nor regional or distant relapses. Conclusion: among patients who suffer from breast cancer at early stages, it showed is possible to apply partial accelerated radiotherapy upon the tumor bed with high doses over 4 days with good to excellent cosmetic results

  14. High-dose ascorbic acid decreases cholesterolemic factors of an atherogenic diet in guinea pigs.

    Science.gov (United States)

    Filis, Konstantinos; Anastassopoulou, Aikaterini; Sigala, Fragiska; Theodorou, Dimitrios; Manouras, Andreas; Leandros, Emanouel; Sigalas, Panagiotis; Hepp, Wolfgang; Bramis, John

    2007-03-01

    The study evaluates the effect of a high supplemental dose of ascorbic acid (AA) on plasma concentrations of total cholesterol (TC), triglycerides (TG), total lipids (TL), and lipoprotein fractions high-density, very-low-density-, and low-density lipoprotein (HDL, VLDL, LDL) in guinea pigs fed with atherogenic diet. Group I consisted of 5 normally fed guinea pigs plus a low dose of AA (1 mg/100 g/day), group II consisted of 7 guinea pigs fed with food enriched with 2% cholesterol plus a low dose of AA (1 mg/100 g/day), and group III consisted of 7 guinea pigs fed with food enriched with 2% cholesterol plus a high dose of AA (30 mg/100 g/day). Cholesterolemic factors concentrations were determined after nine weeks. Concentrations of TC, TG, TL, LDL, and VLDL were increased in group II compared to group I (p < 0.01 for all differences). Supplementation with a high dose of AA resulted in decreased concentrations of TC (p < 0.01), TG (p < 0.01), TL (p < 0.01), and LDL (p < 0.01) in group III compared to group II. Additionally, concentration of HDL was increased in group III compared to group II (p < 0.01). High-dose AA supplementation to an atherogenic diet decreases concentrations of TC, TG, TL, and LDL and increases concentration of HDL compared to low-dose AA.

  15. Use of glasses as radiation detectors for high doses

    International Nuclear Information System (INIS)

    Caldas, L.

    1989-08-01

    Glass samples were tested in relation to the possibility of use in high dose dosimetry in medical and industrial areas. The main characteristics were determined: detection threshold, reproducibility, response to gamma radiation of 137 Cs and 6 Co and thermal decay at ambient temperature, with the use of optical absorption and thermoluminesce techniques. (author) [pt

  16. 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

  17. 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

  18. 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.

  19. Relevance of high-dose chemotherapy in solid tumours

    NARCIS (Netherlands)

    Nieboer, P; de Vries, EGE; Mulder, NH; van der Graaf, WTA

    Drug resistance is a major problem in the treatment of solid tumours. Based on a steep dose-response relationship for especially alkylating agents on tumour cell survival, high-dose chemotherapy was considered of interest for the treatment of solid tumours. Results of phase 1 and 2 studies with

  20. 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

  1. Unusual complication and successful high-dose chemotherapy ...

    African Journals Online (AJOL)

    ... treated with high-dose chemotherapy in our institution, complicated by unusual bilateral renal vein tumour thrombi and tumour lysis syndrome. We believe this unique case highlights the need for early recognition of current and potential complications on staging computed tomography imaging, as well as successful use of ...

  2. Charge collection efficiency in ionization chambers exposed to electron beams with high dose per pulse

    Energy Technology Data Exchange (ETDEWEB)

    Laitano, R F [Istituto Nazionale di Metrologia delle Radiazioni Ionizzanti, ENEA Centro Ricerche Casaccia, c.p. 2400 Rome (Italy); Guerra, A S [Istituto Nazionale di Metrologia delle Radiazioni Ionizzanti, ENEA Centro Ricerche Casaccia, c.p. 2400 Rome (Italy); Pimpinella, M [Istituto Nazionale di Metrologia delle Radiazioni Ionizzanti, ENEA Centro Ricerche Casaccia, c.p. 2400 Rome (Italy); Caporali, C [Istituto Nazionale di Metrologia delle Radiazioni Ionizzanti, ENEA Centro Ricerche Casaccia, c.p. 2400 Rome (Italy); Petrucci, A [A.C.O. S. Filippo Neri, U.O. Fisica Sanitaria, Rome (Italy)

    2006-12-21

    The correction for charge recombination was determined for different plane-parallel ionization chambers exposed to clinical electron beams with low and high dose per pulse, respectively. The electron energy was nearly the same (about 7 and 9 MeV) for any of the beams used. Boag's two-voltage analysis (TVA) was used to determine the correction for ion losses, k{sub s}, relevant to each chamber considered. The presence of free electrons in the air of the chamber cavity was accounted for in determining k{sub s} by TVA. The determination of k{sub s} was made on the basis of the models for ion recombination proposed in past years by Boag, Hochhaeuser and Balk to account for the presence of free electrons. The absorbed dose measurements in both low-dose-per-pulse (less than 0.3 mGy per pulse) and high-dose-per-pulse (20-120 mGy per pulse range) electron beams were compared with ferrous sulphate chemical dosimetry, a method independent of the dose per pulse. The results of the comparison support the conclusion that one of the models is more adequate to correct for ion recombination, even in high-dose-per-pulse conditions, provided that the fraction of free electrons is properly assessed. In this respect the drift velocity and the time constant for attachment of electrons in the air of the chamber cavity are rather critical parameters because of their dependence on chamber dimensions and operational conditions. Finally, a determination of the factor k{sub s} was also made by zero extrapolation of the 1/Q versus 1/V saturation curves, leading to the conclusion that this method does not provide consistent results in high-dose-per-pulse beams.

  3. 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.

  4. Alterations in growth phenotype and radiosensitivity after fractionated irradiation of breast carcinoma cells from a single patient

    International Nuclear Information System (INIS)

    Wazer, D.E.; Joyce, M.; Jung, L.; Band, V.

    1993-01-01

    The purpose was to investigate growth regulation and radiosensitivity in surviving clonogens after fractionated irradiation. Four breast carcinoma cell lines isolated from the primary tumor (21NT, 21PT) and metastases (21MT-1, 21MT-2) of a single patient were exposed to cumulative radiation doses of 30 Gy yielding cell lines designated -IR with respect to their parent. The irradiated lines were then compared to their parent for serum- and growth factor-requirements under defined media conditions, ability to proliferate in soft agar, concentration of TGF-alpha in conditioned medium, and radiosensitivity. The irradiated lines showed no change in proliferative doubling times under serum- and growth factor-supplemented media conditions. A single line, 21MT-1-IR, acquired a limited ability to proliferate in serum- and growth factor-deplete medium with a day 2-4 doubling time of 44.5 hr. Three lines, 21MT-1-IR, 21MT-2-IR, and 21NT-IR, formed colonies in soft agar in contrast to none of the unirradiated parent lines. There were significant 6-8 fold increases in conditioned media TGF-alpha concentrations for 21MT-2-IR and 21NT-IR cells. The 21MT-1-IR and 21NT-IR cells were significantly less radiosensitive than their respective parent lines. This decrease in radiosensitivity appeared to be at least partially mediated by a released factor as the radiosensitivity of 21MT-1 cells was significantly decreased by pre-incubation with conditioned medium from 21MT-1-IR cells. Radiation-induced changes in growth phenotype vary with respect to clonal origin of the cell line and may influence the radiosensitivity of surviving clonogens after fractionated treatment. 18 refs., 4 figs., 3 tabs

  5. Correlation between radiological, scintigraphic and histological changes in bone in rabbits following irradiation with single and fractionated doses

    International Nuclear Information System (INIS)

    Burgener, F.A.; King, M.A.; Weber, D.A.

    1979-01-01

    In the left hind legs of eight rabbits were irradiated with 1,750 rad in a single dose or with 4,650 rad divided over a period of three weeks. These animals, as well as four who had not been irradiated, were examined periodically radiologically and with 99 mTechnetium pyrophosphate scintigrams during one year. No difference could be detected between the results of the single and fractionated doses. Scintigraphically there was a biphasic increase in uptake, the first peak co-inciding with the irradiation and of vascular origin, whereas the second peak occured at four months and was due to a change in bone metabolism. At the end of a year uptake in the irradiated limb was slightly reduced. The earliest radiological changes were found after six months, at the end of the second scintigraphic peak; they consisted of coarsening and blurring of the trabeculae, non-homogeneous spotty mineralisation and endosteal scalloping. Six animals developed a radiation-induced bone sarcoma, first demonstrated either by scintigraphy or radiology depending on its histology. The value of combining radiological and scintigraphic examinations for the early detection of post-radiation abnormalities is stressed. (orig.) [de

  6. 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.

  7. High-dose secondary calibration laboratory accreditation program

    International Nuclear Information System (INIS)

    Humphreys, J.C.

    1993-01-01

    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

  8. Anticoagulation and high dose liver radiation. A preliminary report

    International Nuclear Information System (INIS)

    Lightdale, C.J.; Wasser, J.; Coleman, M.; Brower, M.; Tefft, M.; Pasmantier, M.

    1979-01-01

    Two groups of patients were observed for evidence of acute radiation hepatitis during high dose radiation to the liver. The first group of 18 patients with metastatic liver disease received an average of 4,050 rad to the whole liver. Half received anticoagulation with warfarin. One patient on anticoagulation developed evidence of acute radiation hepatitis while 2 patients did so without anticoagulation. Eleven patients with Hodgkin's disease received 4,000 rad to the left lobe of the liver during extended field radiation. Four of these 11 patients were anticoagulated to therapeutic range. Only one of the fully anticoagulated patients showed changes on liver scan consistent with radiation hepatitis whereas three did so without anticoagulation. No serious sequelae from anticoagulation occurred in either group. These preliminary data suggest that anticoagulation may be safely administered with high dose hepatic radiation and that further trials with anticoagulation are warranted

  9. Radiotherapy and high-dose chemotherapy in advanced Ewing's tumors

    International Nuclear Information System (INIS)

    Pape, H.; Glag, M.; Gripp, S.; Wittkamp, M.; Schmitt, G.; Laws, H.J.; Kaik, B. van; Goebel, U.; Burdach, S.; Juergens, H.

    1999-01-01

    Background: Ewing's tumors are sensitive to radio- and chemotherapy. Patients with multifocal disease suffer a poor prognosis. Patients presenting primary bone marrow involvement or bone metastases at diagnosis herald a 3-year disease-free survival below 15%. The European Intergroup Cooperative Ewing's Sarcoma Study (EICESS) has established the following indications for high-dose therapy in advanced Ewing's tumors: Patients with primary multifocal bone disease, patients with early ( [de

  10. Post-operative high dose rate brachytherapy in patients with low to intermediate risk endometrial cancer

    International Nuclear Information System (INIS)

    Pearcey, R.G.; Petereit, D.G.

    2000-01-01

    This paper investigates the outcome using different dose/fractionation schedules in high dose rate (HDR) post-operative vaginal vault radiotherapy in patients with low to intermediate risk endometrial cancer. The world literature was reviewed and thirteen series were analyzed representing 1800 cases. A total of 12 vaginal vault recurrences were identified representing an overall vaginal control rate of 99.3%. A wide range of dose fractionation schedules and techniques have been reported. In order to analyze a dose response relationship for tumor control and complications, the biologically effective doses to the tumor and late responding tissues were calculated using the linear quadratic model. A threshold was identified for complications, but not vaginal control. While dose fractionation schedules that delivered a biologically effective dose to the late responding tissues in excess of 100 Gy 3 (LQED = 60 Gy) predicted for late complications, dose fractionation schedules that delivered a modest dose to the vaginal surface (50 Gy 10 or LQED = 30 Gy) appeared tumoricidal with vaginal control rates of at least 98%. By using convenient, modest dose fractionation schedules, HDR vaginal vault - brachytherapy yields very high local control and extremely low morbidity rates. (author)

  11. High-dose buprenorphine: perioperative precautions and management strategies.

    Science.gov (United States)

    Roberts, D M; Meyer-Witting, M

    2005-02-01

    Buprenorphine has been in clinical use in anaesthesia for several decades. Recently, the high-dose sublingual formulation (Subutex, Reckitt Benckiser, Slough, U.K.) has been increasingly used as maintenance therapy in opioid dependence, as an alternative to methadone and other pharmacological therapies. Buprenorphine has unique pharmacological properties making it well suited for use as a maintenance therapy in opioid dependence. However, these same properties may cause difficulty in the perioperative management of pain. Buprenorphine is a partial opioid agonist, attenuating the effects of supplemental illicit or therapeutic opioid agonists. As a result of its high receptor affinity, supplemental opioids do not readily displace buprenorphine from the opioid receptor in standard doses. High-dose buprenorphine has an extended duration of action that prolongs both of these effects. The perioperative management of patients stabilized on high-dose buprenorphine and undergoing surgery requires consideration of the likely analgesic requirements. Where possible the buprenorphine should be continued. Pain management should focus on maximizing non-opioid analgesia, local anaesthesia and non-pharmacological techniques. Where pain may not be adequately relieved by these methods, the addition of a full opioid agonist such as fentanyl or morphine at appropriate doses should be considered, accompanied by close monitoring in a high dependency unit. In situations where this regimen is unlikely to be effective, preoperative conversion to morphine or methadone may be an option. Where available, liaison with a hospital-based alcohol and drug service should always be considered.

  12. A novel theory of radiation damage at high doses

    International Nuclear Information System (INIS)

    Seeger, A.; Stuttgart Univ.

    1989-01-01

    Deviations of radiation damage (in the case of metals usually monitored by the residual electrical resistivity) from proportionality with the irradiation dose have so far been analysed almost exclusively in terms of extensions of models originally developed for small doses. The present theory considers the opposite limit i.e. the quasi-saturated state. It is argued that at high doses the Lueck-Sizmann effect may result in a self-organization of clusters of vacancies and self-interstitials, forming a heterogeneous froth. Possible structures of this froth and its effect on the electrical resistivity of metals are discussed. The model is shown to account for the dependence of the ''saturation resistivity'' on the nature of the irradiation as well as for several other hitherto poorly explained observations. Among them are the electrical-resistivity variation induced by high-dose irradiation with heavy ions, the amorphization of certain alloys by high-dose electron irradiation, and the occurrence of ordered arrays of stacking-fault tetrahedra after in-situ irradiations in high-voltage electron microscopes. (author)

  13. Radiophotoluminescence light scope for high-dose dosimetry

    International Nuclear Information System (INIS)

    Sato, Fuminobu; Zushi, Naoki; Sakiyama, Tomoki; Kato, Yushi; Murata, Isao; Shimizu, Kikuo; Yamamoto, Takayoshi; Iida, Toshiyuki

    2015-01-01

    A radiophotoluminescence (RPL) light scope is a remote-sensing technique for measuring in situ the radiation dose in an RPL detector placed at a distance. The RPL light scope is mainly composed of an ultraviolet (UV) pulse laser, telescopic lenses, a photomultiplier tube, and camera modules. In a performance test, some RPL detectors were placed at distances up to 30 m and were illuminated with a pulsed UV laser beam. The photoluminescence responses of the RPL detectors were analyzed using this scope. Their radiation doses were determined from the amplitude of the given component of the photoluminescence responses. The RPL readout could be repeated without fading, and its amplitude exhibited good linearity at a dose ranging from 0.1 to 60 Gy. Furthermore, a two-dimensional distribution of radiation dose was obtained by laser scanning on an RPL detector. It was confirmed that the RPL light scope was a useful remote-sensing tool for high-dose dosimetry. - Highlights: • A radiophotoluminescence (RPL) light scope was developed for high-dose dosimetry. • The RPL light scope has high sensitivity and accuracy in high-dose dosimetry. • Two-dimensional radiation dose distribution was obtained by the RPL light scope.

  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. Precision, high dose radiotherapy: helium ion treatment of uveal melanoma

    International Nuclear Information System (INIS)

    Saunders, W.M.; Char, D.H.; Quivey, J.M.

    1985-01-01

    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

  16. Physics and quality assurance for brachytherapy - Part I: High dose rates

    International Nuclear Information System (INIS)

    Anderson, Lowell L.

    1997-01-01

    Purpose: To review the physical aspects of high dose rate (HDR) brachytherapy, including commissioning and quality assurance, source calibration and dose distribution measurements, and treatment planning methods. Following the introduction of afterloading in brachytherapy, development efforts to make it 'remote' culminated in 1964 with the near-simultaneous appearance of remote afterloaders in five major medical centers. Four of these machines were 'high dose rate', three employing 60Co and one (the GammaMed) using a single, cable-mounted 192Ir source. Stepping-motor source control was added to the GammaMed in 1974, making it the precursor of modern remote afterloaders, which are now suitable for interstitial, well as intracavitary brachytherapy by virtue of small source-diameter and indexer-accessed multiple channels. Because the 192Ir sources currently used in HDR remote afterloaders are supplied at a nominal air-kerma strength of 11.4 cGy cm2 s-1 (10 Ci), are not collimated in clinical use, and emit a significant fraction (15%) of photons at energies greater than 600 keV, shielding and facility design must be undertaken as carefully and thoroughly as for external beam installations. Licensing requirements of regulatory agencies must be met with respect both to maximum permissible dose limits and to the existence and functionality of safety devices (door interlocks, radiation monitors, etc.). Commissioning and quality assurance procedures that must be documented for HDR remote afterloading relate to (1) machine, applicator, guide-tube, and facility functionality checks, (2) source calibration, (3) emergency response readiness, (4) planning software evaluation, and (5) independent checks of clinical dose calculations. Source calibration checks must be performed locally, either by in-air measurement of air kerma strength or with a well ionization chamber calibrated (by an accredited standards laboratory) against an in-air measurement of air kerma strength for the

  17. The influence of single and fractionated dose external beam irradiation on injury-induced arterial smooth muscle cell proliferation

    International Nuclear Information System (INIS)

    Schaefer, U.; Micke, O.; Dorszewski, A.; Breithardt, G.; Willich, N.

    1997-01-01

    Purpose/Objective: Restenosis after catheter-based revascularization has been demonstrated to be primarily caused by smooth muscle cell proliferation. This study examined the effects of external beam irradiation on neointimal proliferation after external injury to the central artery of the rabbit ear. Materials and Methods: 40 male New Zealand White rabbits were used in this study. Crush lesions were performed on each ear under general anesthesia and bilateral auricular nerve blockade. A single dose of 12 Gy (n=10), 16 Gy (n=10), or 20 Gy (n=10) and a fractionated dose of 4 x 5 Gy (n=10) gamma radiation was delivered to the left or right central artery of the ear 24 hours after injury; the contralateral central artery served as control. All rabbits were sacrificed after twenty-one days and the central arteries of the ear were fixed for morphometric measurements. Results: Mean (± SD) neointimal area was 0.062 ± 0.005 mm 2 (12 Gy), 0.022 ± 0,005 mm 2 (16 Gy), 0,028 ± 0,006 mm 2 and 0.038 mm 2 ± 0,02 mm 2 (4 x 5 Gy) in irradiated arteries compared with 0,081 ± 0,009 mm 2 in the control group. Mean (±SD) luminal area was 0.049 ± 0.004 mm 2 (12 Gy), 0.059 ± 0.002 mm 2 (16 Gy), 0.072 ± 0,006 mm 2 (20 Gy) and 0.048 mm 2 ± 0,018 mm 2 (4 x 5 Gy) in irradiated arteries compared with 0,043 ± 0,008 mm 2 in the control group. The difference in neointimal and luminal area between control and irradiated arteries was significant (p<0.05) only for the 16 and 20 Gy group compared to control. Conclusion: We conclude that in this model, external beam X-ray irradiation was successful in reducing neointimal proliferation after injury of the central artery of the rabbit ear. The optimal dose seems to be a single dose of 16 Gy - 20 Gy. Only a less prominent effect was noted for a fractionated dose of 4 x 5 Gy. Whether this approach can be used successfully to inhibit restenosis in the clinical setting requires further investigation

  18. Effects of high doses of intracoronary adenosine on the assessment of fractional flow reserve

    Directory of Open Access Journals (Sweden)

    Ahmed Khashaba

    2014-03-01

    Conclusions: Intracoronary adenosine, at doses higher than currently suggested, lows obtaining FFR values similar to IV adenosine. Intravenous adenosine, which remains the gold standard, might thus be reserved for those lesions with equivocal FFR values.

  19. Effect of high-dose dexamethasone on perioperative lactate levels and glucose control : a randomized controlled trial

    NARCIS (Netherlands)

    Ottens, Thomas H; Nijsten, Maarten W N; Hofland, Jan; Dieleman, Stefan; Hoekstra, Miriam; van Dijk, Diederik; van der Maaten, Joost Maa

    2015-01-01

    INTRODUCTION: Blood lactate levels are increasingly used to monitor patients. Steroids are frequently administered to critically ill patients. However, the effect of steroids on lactate levels has not been adequately investigated. We studied the effect of a single intraoperative high dose of

  20. Adjuvant high dose rate vaginal cuff brachytherapy for early stage endometrial cancer

    International Nuclear Information System (INIS)

    Tannehill, S.P.; Petereit, D.G.; Schink, J.C.; Grosen, E.A.; Hartenbach, E.M.; Thomadsen, B.R.; Buchler, D.A.

    1997-01-01

    Objective: To determine the efficacy and complications of adjuvant high dose rate (HDR) vaginal cuff brachytherapy (VCB) in patients (pts) with low risk endometrial carcinoma. Materials and Methods: Since 1989, 154 patients were treated with outpatient adjuvant VCB for low risk endometrial cancer (Stage IA-14%, Stage IB-82%). Four percent of patients with stage IC disease were treated with VCB only because of medical contraindications to pelvic radiation. Patients had the following histologic grades: 53% grade 1, 40% grade 2, 5% grade 3 and 3% unknown (99%-adenocarcinoma, <1% papillary serous histology). Seventy-three percent of patients had their surgery (TAH-BSO) performed at an outside institution with minimal surgical assessment of the lymph nodes. At a median of 6 weeks after surgery, patients were treated with 2 HDR VCB insertions delivered 1 week apart. Ovoids were placed at the vaginal apex to deliver 16.2 Gy per fraction to the vaginal surface (LDR equivalent of 60 Gy at 100 cGy/h) under conscious outpatient sedation. All clinical endpoints were calculated using the Kaplan Meier method. Complications were scored using the RTOG 5-tiered system. Results: The median time in the brachytherapy suite was 60 minutes with no acute complications observed. With a median follow-up of 33 months (3-79 months), the 4-year overall and disease-free survival were 93% and 96% respectively. Five patients (3%) recurred: 2 intra-abdominally, 1 with lung metastases, and 2 in the pelvic lymph nodes. There were no vaginal cuff recurrences. The single patient with an isolated pelvic sidewall recurrence was salvaged with pelvic RT. Six patients developed a small area of asymptomatic necrosis at the vaginal cuff, which spontaneously healed at a median time of 4 months. There were no grade 3 or greater late tissue toxicities. No patient experienced significant vaginal stenosis, with 20% of the patients experiencing mild fibrosis of the vaginal apex. Conclusions: Adjuvant HDR VCB in 2

  1. 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

  2. Endobronchial and endoesophageal high dose rate brachytherapy for malignant airway and digestive tract obstructions

    International Nuclear Information System (INIS)

    Mehta, Minesh P.

    1996-01-01

    With an annual incidence of more than 160,000 cases and a local failure rate between 30-50%, endobronchial occlusion seen with lung cancer is a common and potentially life-threatening complication. Several methods of managing this exist and recently endobronchial brachytherapy has been used extensively as a consequence of the development of fiberoptic bronchoscopy and high dose rate remote afterloading technology. Procedurally, one or more afterloading catheters are inserted in the involved portions of the tracheobronchial tree through fiberoptic guidance. Treatment techniques range from 1-4 applications fractionated over several weeks or given over 2 days with a single insertion procedure. Almost all procedures are currently performed in the outpatient setting. The major application of this technology is in the palliation of occlusive symptomatology. Clinical improvement ranges from 50-100%, radiographic reaeration ranges from 46-88% and bronchoscopic responses ranges from 59-100%. Symptomatic relief is usually quite durable with more than 70% of the patients' remaining life-time rendered symptom-free and symptom-improved. Recently, this modality has been explored for its curative potential as a boost following external beam radiotherapy. It is clear from these series, that in selected patients, endobronchial boost produces significant reaeration and sparing of lung volume from subsequent external radiation, and a few cases may even become resectable. Demonstration of the survival advantage will, however, require larger clinical trials with adequate controls. Some reports have suggested an unacceptably high rate of fatal hemoptysis following HDR endobronchial brachytherapy. Review of the world literature suggests that fatal hemoptysis rates range from 0-50% with an average of about 8%, comparable to an average of 5% with low dose rate brachytherapy. Other recognized complications include fistulae and radiation bronchitis. Because the majority of patients with

  3. Adverse Outcomes After Palliative Radiation Therapy for Uncomplicated Spine Metastases: Role of Spinal Instability and Single-Fraction Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Lam, Tai-Chung, E-mail: lamtaichung@gmail.com [Department of Radiation Oncology, Dana-Farber/Brigham and Women' s Cancer Center, Boston, Massachusetts (United States); Uno, Hajime [Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, Boston, Massachusetts (United States); Krishnan, Monica [Department of Radiation Oncology, Dana-Farber/Brigham and Women' s Cancer Center, Boston, Massachusetts (United States); Lutz, Steven [Department of Radiation Oncology, Blanchard Valley Regional Medical Center, Findlay, Ohio (United States); Groff, Michael [Department of Neurosurgery, Brigham and Women' s Hospital, Boston, Massachusetts (United States); Cheney, Matthew [Harvard Radiation Oncology Program, Boston, Massachusetts (United States); Balboni, Tracy [Department of Radiation Oncology, Dana-Farber/Brigham and Women' s Cancer Center, Boston, Massachusetts (United States); Department of Psychosocial Oncology and Palliative Care, Dana-Farber Cancer Institute, Boston, Massachusetts (United States)

    2015-10-01

    Purpose: Level I evidence demonstrates equivalent pain response after single-fraction (SF) or multifraction (MF) radiation therapy (RT) for bone metastases. The purpose of this study is to provide additional data to inform the incidence and predictors of adverse outcomes after RT for spine metastases. Methods and Materials: At a single institution, 299 uncomplicated spine metastases (without cord compression, prior RT, or surgery) treated with RT from 2008 to 2013 were retrospectively reviewed. The spinal instability neoplastic score (SINS) was used to assess spinal instability. The primary outcome was time to first spinal adverse event (SAE) at the site, including symptomatic vertebral fracture, hospitalization for site-related pain, salvage surgery, interventional procedure, new neurologic symptoms, or cord compression. Fine and Gray's multivariable model assessed associations of the primary outcome with SINS, SF RT, and other significant baseline factors. Propensity score matched analysis further assessed the relationship of SF RT to first SAEs. Results: The cumulative incidence of first SAE after SF RT (n=66) was 6.8% at 30 days, 16.9% at 90 days, and 23.6% at 180 days. For MF RT (n=233), the incidence was 3.5%, 6.4%, and 9.2%, respectively. In multivariable analysis, SF RT (hazard ratio [HR] = 2.8, 95% confidence interval [CI] 1.5-5.2, P=.001) and SINS ≥11 (HR=2.5 , 95% CI 1.3-4.9, P=.007) were predictors of the incidence of first SAE. In propensity score matched analysis, first SAEs had developed in 22% of patients with SF RT versus 6% of those with MF RT cases (HR=3.9, 95% CI 1.6-9.6, P=.003) at 90 days after RT. Conclusion: In uncomplicated spinal metastases treated with RT alone, spinal instability with SINS ≥11 and SF RT were associated with a higher rate of SAEs.

  4. A Simple Fractionated Extraction Method for the Comprehensive Analysis of Metabolites, Lipids, and Proteins from a Single Sample.

    Science.gov (United States)

    Salem, Mohamed; Bernach, Michal; Bajdzienko, Krzysztof; Giavalisco, Patrick

    2017-06-01

    Understanding of complex biological systems requires the measurement, analysis and integration of multiple compound classes of the living cell, usually determined by transcriptomic, proteomic, metabolomics and lipidomic measurements. In this protocol, we introduce a simple method for the reproducible extraction of metabolites, lipids and proteins from biological tissues using a single aliquot per sample. The extraction method is based on a methyl tert-butyl ether: methanol: water system for liquid: liquid partitioning of hydrophobic and polar metabolites into two immiscible phases along with the precipitation of proteins and other macromolecules as a solid pellet. This method, therefore, provides three different fractions of specific molecular composition, which are fully compatible with common high throughput 'omics' technologies such as liquid chromatography (LC) or gas chromatography (GC) coupled to mass spectrometers. Even though the method was initially developed for the analysis of different plant tissue samples, it has proved to be fully compatible for the extraction and analysis of biological samples from systems as diverse as algae, insects, and mammalian tissues and cell cultures.

  5. High dose vitamin K3 infusion in advanced hepatocellular carcinoma.

    Science.gov (United States)

    Sarin, Shiv K; Kumar, Manoj; Garg, Sanjay; Hissar, Syed; Pandey, Chandana; Sharma, Barjesh C

    2006-09-01

    The survival of patients with unresectable advanced hepatocellular carcinoma (HCC) with portal vein thrombosis is dismal. Current therapeutic options have limited efficacy. Vitamin K has been shown to have antitumor effect on HCC cells both in cell lines and patients with advanced HCC. The aim of this study was to assess the clinical efficacy of high dose vitamin K3 in the treatment of advanced HCC with portal vein thrombosis. Forty-two consecutive patients with advanced HCC (Stage C according to BCLC staging system) with portal vein thrombosis were randomized into two groups: (i) high dose vitamin K3 (n = 23); and (ii) placebo (n = 19). The vitamin K3 was administered by i.v. infusion of 50 mg/day with daily increase of dose by 50 mg for 6 days, followed by 20 mg i.m. twice daily for 2 weeks. Of the 23 patients treated with vitamin K, one (4.3%) achieved complete response and three (13%) partial response, for a total of four (17.4%) objective responders overall. The overall mean survival was 8.9 +/- 8.8 months (median: 6; range 1-37 months) in the vitamin K group and 6.8 +/- 5.3 months (median: 5; range 1.5-21 months) in the placebo group (P = 0.552). The mean duration of survival was longer in patients in the vitamin K group who achieved objective response (22.5 +/- 12.2; median: 21; range 11-37 months) as compared to patients not achieving objective response (6.1 +/- 4.6; median: 5; range 1-16 months) (P = 0.0.002). Portal vein thrombosis resolved with complete patency in one (4.35%) patient. Treatment with high dose vitamin K produces objective response in 17% patients with improved survival in patients achieving objective response; however, it does not affect the overall survival.

  6. Cooperative binding mitigates the high-dose hook effect.

    Science.gov (United States)

    Roy, Ranjita Dutta; Rosenmund, Christian; Stefan, Melanie I

    2017-08-14

    The high-dose hook effect (also called prozone effect) refers to the observation that if a multivalent protein acts as a linker between two parts of a protein complex, then increasing the amount of linker protein in the mixture does not always increase the amount of fully formed complex. On the contrary, at a high enough concentration range the amount of fully formed complex actually decreases. It has been observed that allosterically regulated proteins seem less susceptible to this effect. The aim of this study was two-fold: First, to investigate the mathematical basis of how allostery mitigates the prozone effect. And second, to explore the consequences of allostery and the high-dose hook effect using the example of calmodulin, a calcium-sensing protein that regulates the switch between long-term potentiation and long-term depression in neurons. We use a combinatorial model of a "perfect linker protein" (with infinite binding affinity) to mathematically describe the hook effect and its behaviour under allosteric conditions. We show that allosteric regulation does indeed mitigate the high-dose hook effect. We then turn to calmodulin as a real-life example of an allosteric protein. Using kinetic simulations, we show that calmodulin is indeed subject to a hook effect. We also show that this effect is stronger in the presence of the allosteric activator Ca 2+ /calmodulin-dependent kinase II (CaMKII), because it reduces the overall cooperativity of the calcium-calmodulin system. It follows that, surprisingly, there are conditions where increased amounts of allosteric activator actually decrease the activity of a protein. We show that cooperative binding can indeed act as a protective mechanism against the hook effect. This will have implications in vivo where the extent of cooperativity of a protein can be modulated, for instance, by allosteric activators or inhibitors. This can result in counterintuitive effects of decreased activity with increased concentrations of

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

    International Nuclear Information System (INIS)

    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

    2014-01-01

    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.

  8. Effect of high dose irradiation on the red cell span in rabbits

    International Nuclear Information System (INIS)

    Kang, T.W.; Koh, J.W.; Woo, K.S.; Lee, O.H.; Youn, C.S.

    1982-01-01

    As a part of studies on acute effects of high dose irradiation in vivo, the present report was carried out to evaluate the changes of the red cell life span in the white rabbits by a single whole body exposure to gamma rays from 60 Co teletherapy unit. The exposure was done in dose levels of 100, 600 and 900 rads to each experimental group of 10 rabbits. The life span apparent half survival time of red cells, and that the red cell volume in the circulting blood were measured by ICSH Reference method using 51 Cr. (Author)

  9. Epithelial regeneration of transposed intestine after high doses of X-irradiation

    International Nuclear Information System (INIS)

    Both, N.J. de; Vermey, M.

    1976-01-01

    The regeneration capacities of normal and transposed small bowel epithelium were compared in rats after applying high doses of X-irradiation. It has been shown that the potency of the mucosa to regenerate was much higher than assumed and that the mucosa could regenerate after single doses varying from 2000 to 5000 R. Even in the villus epithelium and in flat epithelium covering infiltrates of the lamina propria cells survived, which were still able to resume proliferative activity several days after irradiation. (author)

  10. Radiation processing and high-dose dosimetry at ANSTO

    International Nuclear Information System (INIS)

    Gant, G.J.; Saunders, M.; Banos, C.; Mo, L.; Davies, J.; Evans, O.

    2001-01-01

    The Radiation Technology group at ANSTO is part of the Physics Division and provides services and advice in the areas of gamma irradiation and high-dose dosimetry. ANSTO's irradiation facilities are designed for maximum dose uniformity and provide a precision irradiation service unique in Australia. Radiation Technology makes and sells reference and transfer standard dosimeters which are purchased by users and suppliers of commercial irradiation services in Australia and the Asia-Pacific region. A calibration service is also provided for dosimeters purchased from other suppliers

  11. An evaluation of high-dose jobs for ALARA improvement

    International Nuclear Information System (INIS)

    Mun, J. H.; Kim, H. S.

    1997-01-01

    It is well known that about 70 percent of occupational dose have incurred from maintenance jobs at outage period. To reduce occupational dose, first, the high-dose jobs at the outage period should be identified and evaluated. For this, the database program is used, which contains the ORE data of reference plants, Kori Units 3 and 4. As a result, it is found that the jobs related to steam generator are the highest dose jobs in terms of collective ORE dose. From the analysis of the job procedures of those jobs, the ALARA improvements are also derived

  12. 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.

  13. Establishment of a dosimetric system for high doses using glasses

    International Nuclear Information System (INIS)

    Correa Quezada, Valeria de la Asuncion

    1997-01-01

    A routine dosimetric system was developed using commercial glass samples. The dosimetric characteristics of national and imported samples were studied: batch uniformity, response repeatability, reutilization, absorbed dose response, detection range, response stability as a function of absorbed dose, storage temperature and thermal treatments pre- and post-irradiation, using the optical absorption technique. As an application, the dosimetric system was tested in a flower irradiation process at IPEN. All the obtained results show the usefulness of the proposed system for high dose dosimetry. (author)

  14. Dose escalation using conformal high-dose-rate brachytherapy improves outcome in unfavorable prostate cancer.

    Science.gov (United States)

    Martinez, Alvaro A; Gustafson, Gary; Gonzalez, José; Armour, Elwood; Mitchell, Chris; Edmundson, Gregory; Spencer, William; Stromberg, Jannifer; Huang, Raywin; Vicini, Frank

    2002-06-01

    To overcome radioresistance for patients with unfavorable prostate cancer, a prospective trial of pelvic external beam irradiation (EBRT) interdigitated with dose-escalating conformal high-dose-rate (HDR) prostate brachytherapy was performed. Between November 1991 and August 2000, 207 patients were treated with 46 Gy pelvic EBRT and increasing HDR brachytherapy boost doses (5.50-11.5 Gy/fraction) during 5 weeks. The eligibility criteria were pretreatment prostate-specific antigen level >or=10.0 ng/mL, Gleason score >or=7, or clinical Stage T2b or higher. Patients were divided into 2 dose levels, low-dose biologically effective dose 93 Gy (149 patients). No patient received hormones. We used the American Society for Therapeutic Radiology and Oncology definition for biochemical failure. The median age was 69 years. The mean follow-up for the group was 4.4 years, and for the low and high-dose levels, it was 7.0 and 3.4 years, respectively. The actuarial 5-year biochemical control rate was 74%, and the overall, cause-specific, and disease-free survival rate was 92%, 98%, and 68%, respectively. The 5-year biochemical control rate for the low-dose group was 52%; the rate for the high-dose group was 87% (p failure. The Radiation Therapy Oncology Group Grade 3 gastrointestinal/genitourinary complications ranged from 0.5% to 9%. The actuarial 5-year impotency rate was 51%. Pelvic EBRT interdigitated with transrectal ultrasound-guided real-time conformal HDR prostate brachytherapy boost is both a precise dose delivery system and a very effective treatment for unfavorable prostate cancer. We demonstrated an incremental beneficial effect on biochemical control and cause-specific survival with higher doses. These results, coupled with the low risk of complications, the advantage of not being radioactive after implantation, and the real-time interactive planning, define a new standard for treatment.

  15. Effect of Concurrent High-Dose Cisplatin Chemotherapy and Conformal Radiotherapy on Cervical Esophageal Cancer Survival

    International Nuclear Information System (INIS)

    Huang Shaohui; Lockwood, Gina; Brierley, James; Cummings, Bernard; Kim, John; Wong, Rebecca; Bayley, Andrew; Ringash, Jolie

    2008-01-01

    Purpose: To determine whether a change in treatment policy to conformal, elective nodal radiotherapy and concurrent high-dose cisplatin improved survival for cervical esophageal cancer patients. Methods and Materials: All cervical esophageal cancer patients treated between 1997 and 2005 were restaged (1983 American Joint Committee on Cancer criteria). Patients treated before 2001 (previous cohort [PC]) were compared with those treated from 2001 onward (recent cohort [RC]). The PC institutional chemoradiotherapy protocol was 54 Gy in 20 fractions within 4 weeks, with 5-fluorouracil (1,000 mg/m 2 ) on Days 1-4 and either mitomycin C (10 mg/m 2 ) or cisplatin (75 mg/m 2 ) on Day 1. The RC institutional chemoradiotherapy protocol was conformal radiotherapy, 70 Gy in 35 fractions within 7 weeks, to the primary tumor and elective nodes, with high-dose cisplatin (100 mg/m 2 ) on Days 1, 22, and 43. Results: The median follow-up was 3.1 years (PC, 8.1 and RC, 2.3). Of 71 patients (25 women and 46 men), 21 of 29 in the PC and 29 of 42 in the RC were treated curatively (curative subgroup, n = 50). Between the two groups, no differences in overall survival or locoregional relapse-free survival were seen. The overall survival rate at 2 and 5 years was 35% (range, 24-47%) and 21% (range, 12-32%) in the whole group and 46% (range 32-60%) and 28% (range, 15-42%) in the curative group, respectively. In the curative group, no statistically significant prognostic factors were found. Trends toward better locoregional relapse-free survival were seen in women (2-year rate, 73% vs. for men, 36%; p = 0.08) and in patients aged >64 years (2-year rate, 68% vs. age ≤64 years, 34%; p = 0.10). Conclusion: No survival improvement could be demonstrated after changing the treatment policy to high-dose cisplatin-based, conventionally fractionated conformal chemoradiotherapy. Female gender and older age might predict for better outcomes

  16. Low dose radiation enhance the anti-tumor effect of high dose radiation on human glioma cell U251

    International Nuclear Information System (INIS)

    Wang Chang; Wang Guanjun; Tan Yehui; Jiang Hongyu; Li Wei

    2008-01-01

    Objective: To detect the effect on the growth of human glioma cell U251 induced by low dose irradiation and low dose irradiation combined with large dose irradiation. Methods: Human glioma cell line U251 and nude mice carried with human glioma were used. The tumor cells and the mice were treated with low dose, high dose, and low dose combined high dose radiation. Cells growth curve, MTT and flow cytometry were used to detect the proliferation, cell cycle and apoptosis of the cells; and the tumor inhibition rate was used to assess the growth of tumor in vivo. Results: After low dose irradiation, there was no difference between experimental group and control group in cell count, MTT and flow cytometry. Single high dose group and low dose combined high dose group both show significantly the suppressing effect on tumor cells, the apoptosis increased and there was cell cycle blocked in G 2 period, but there was no difference between two groups. In vivo apparent anti-tumor effect in high dose radiation group and the combining group was observed, and that was more significant in the combining group; the prior low dose radiation alleviated the injury of hematological system. There was no difference between single low dose radiation group and control. Conclusions: There is no significant effect on human glioma cell induced by low dose radiation, and low dose radiation could not induce adaptive response. But in vivo experience, low dose radiation could enhance the anti-tumor effect of high dose radiation and alleviated the injury of hematological system. (authors)

  17. The influence of high doses of radiation in citrine stones

    International Nuclear Information System (INIS)

    Teixeira, M. I.; Caldas, L. V. E.

    2014-08-01

    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 ( 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 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)

  18. High-dose contrast-enhanced MRI in multiple sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Koudriavtseva, T. [Department of Neurosciences, University of Rome ``La Sapienza`` Rome (Italy); Pozzilli, C. [Department of Neurosciences, University of Rome ``La Sapienza`` Rome (Italy); Di Biasi, C. [MR Unit, Clinica Medica 1, University of Rome ``La Sapienza``, Rome (Italy); Iannilli, M. [MR Unit, Clinica Medica 1, University of Rome ``La Sapienza``, Rome (Italy); Trasimeni, G. [MR Unit, Clinica Medica 1, University of Rome ``La Sapienza``, Rome (Italy); Gasperini, C. [Department of Neurosciences, University of Rome ``La Sapienza`` Rome (Italy); Argentino, C. [Department of Neurosciences, University of Rome ``La Sapienza`` Rome (Italy); Gualdi, G.F. [MR Unit, Clinica Medica 1, University of Rome ``La Sapienza``, Rome (Italy)

    1996-05-01

    Contrast-enhanced MRI is effective for assessing disease activity in multiple sclerosis (MS) and may provide an outcome measure for testing the efficacy of treatment in clinical trials. To compare the sensitivity of high-dose gadolinium-HP-DO3A with that of a standard dose of gadolinium-DTPA, we studied 16 patients with relapsing-remitting MS in the acute phase of the disease. Each underwent two MRI examinations within at most 48 h. The initial MRI study was with a standard dose of gadolinium-DTPA (0.1 mmol/kg), and the second one an experimental dose of gadolinium-HP-DO3A (0.3 mmol/kg). No adverse effects were attributed to the contrast media. The high-dose study revealed more enhancing lesions than the standard-dose study (56 vs 38). This difference was found to be more relevant for infratentorial and small lesions. Furthermore, with the higher dose, there was a marked qualitative improvement in the visibility and delineation of the lesions. (orig.). With 4 figs., 2 tabs.

  19. TL response of citrine samples for high-dose dosimetry

    International Nuclear Information System (INIS)

    Teixeira, Maria Ines; Caldas, Linda V.E.

    2011-01-01

    The possibility of using samples of Brazilian stones as quartz, amethyst, topaz, etc. for high-dose dosimetry has been studied in recent years at IPEN, using the thermoluminescence technique (TL). In this work, the TL properties of citrine samples were studied. They were exposed to different doses of gamma radiation ( 60 Co). The natural citrine stone was extracted from a mine in Minas Gerais state, Brazil; it is a tectosilicate ranked as one of three-dimensional structure, showing clear yellow to golden brown color. The natural citrine stone is classified as quartz (SiO 2 ), and it has a lower symmetry and more compact reticulum. The citrine stone samples were powdered, and the selected grains were mixed with Teflon in the proportion 2 (Teflon):1 (Citrine). The mixture was pressed and sintered for production of Citrine -Teflon pellets of 50 mg. The TL emission curve showed two peaks at 160 deg C and 220 deg C. To remove the TL peak (160 deg 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 preliminary results show that citrine may be useful for high-dose dosimetry. (author)

  20. 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.

  1. High-dose contrast-enhanced MRI in multiple sclerosis

    International Nuclear Information System (INIS)

    Koudriavtseva, T.; Pozzilli, C.; Di Biasi, C.; Iannilli, M.; Trasimeni, G.; Gasperini, C.; Argentino, C.; Gualdi, G.F.

    1996-01-01

    Contrast-enhanced MRI is effective for assessing disease activity in multiple sclerosis (MS) and may provide an outcome measure for testing the efficacy of treatment in clinical trials. To compare the sensitivity of high-dose gadolinium-HP-DO3A with that of a standard dose of gadolinium-DTPA, we studied 16 patients with relapsing-remitting MS in the acute phase of the disease. Each underwent two MRI examinations within at most 48 h. The initial MRI study was with a standard dose of gadolinium-DTPA (0.1 mmol/kg), and the second one an experimental dose of gadolinium-HP-DO3A (0.3 mmol/kg). No adverse effects were attributed to the contrast media. The high-dose study revealed more enhancing lesions than the standard-dose study (56 vs 38). This difference was found to be more relevant for infratentorial and small lesions. Furthermore, with the higher dose, there was a marked qualitative improvement in the visibility and delineation of the lesions. (orig.). With 4 figs., 2 tabs

  2. Radiation safety program in a high dose rate brachytherapy facility

    International Nuclear Information System (INIS)

    Rodriguez, L.V.; Hermoso, T.M.; Solis, R.C.

    2001-01-01

    The use of remote afterloading equipment has been developed to improve radiation safety in the delivery of treatment in brachytherapy. Several accidents, however, have been reported involving high dose-rate brachytherapy system. These events, together with the desire to address the concerns of radiation workers, and the anticipated adoption of the International Basic Safety Standards for Protection Against Ionizing Radiation (IAEA, 1996), led to the development of the radiation safety program at the Department of Radiotherapy, Jose R. Reyes Memorial Medical Center and at the Division of Radiation Oncology, St. Luke's Medical Center. The radiation safety program covers five major aspects: quality control/quality assurance, radiation monitoring, preventive maintenance, administrative measures and quality audit. Measures for evaluation of effectiveness of the program include decreased unnecessary exposures of patients and staff, improved accuracy in treatment delivery and increased department efficiency due to the development of staff vigilance and decreased anxiety. The success in the implementation required the participation and cooperation of all the personnel involved in the procedures and strong management support. This paper will discuss the radiation safety program for a high dose rate brachytherapy facility developed at these two institutes which may serve as a guideline for other hospitals intending to install a similar facility. (author)

  3. ELDRS Characterization for a Very High Dose Mission

    Science.gov (United States)

    Harris, Richard D.; McClure, Steven S.; Rax, Bernard G.; Kenna, Aaron J.; Thorbourn, Dennis O.; Clark, Karla B.; Yan, Tsun-Yee

    2010-01-01

    Evaluation of bipolar linear parts which may have Enhanced Low Dose Rate Sensitivity (ELDRS) is problematic for missions that have very high dose radiation requirements. The accepted standards for evaluating parts that display ELDRS require testing at a very low dose rate which could be prohibitively long for very high dose missions. In this work, a methodology for ELDRS characterization of bipolar parts for mission doses up to 1 Mrad(Si) is evaluated. The procedure employs an initial dose rate of 0.01 rad(Si)/s to a total dose of 50 krad(Si) and then changes to 0.04 rad(Si)/s to a total dose of 1 Mrad(Si). This procedure appears to work well. No change in rate of degradation with dose has been observed when the dose rate is changed from 0.01 to 0.04 rad(Si)/s. This is taken as an indication that the degradation due to the higher dose rate is equivalent to that at the lower dose rate at the higher dose levels, at least for the parts studied to date. In several cases, significant parameter degradation or functional failure not observed at HDR was observed at fairly high total doses (50 to 250 krad(Si)) at LDR. This behavior calls into question the use of dose rate trend data and enhancement factors to predict LDR performance.

  4. Methodology of high dose research in medical radiodiagnostic

    International Nuclear Information System (INIS)

    Barboza, Adriana E.; Martins, Cintia P. de S.

    2013-01-01

    This work has as main purpose to study occupational exposure in diagnostic radiology in medical cases of high doses recorded in 2011 at the national level . These doses were recorded by monitoring individual of the occupationally exposed individuals (OEI's). This monitoring of the doses received by ionizing radiation has as main objective to ensure that the principle of dose limitation is respected. In this study it were evaluated doses of 372 OEI's radiology in different Brazilian states. Doses were extracted from the database of Sector Management Doses of the Institute for Radioprotection and Dosimetry - IRD/CNEN-RJ, Brazil. The information from the database provide reports of doses from several states, which allows to quantify statistically, showing those with the highest doses in four areas: dose greater than or equal to 20 mSv apron and chest and dose greater than or equal to 100 mSv apron and chest. The identification of these states allows the respective Sanitary Surveillance (VISA), be aware of the events and make plans to reduce them. This study clarified the required procedures when there is a record of high dose emphasizing the importance of using protective radiological equipment, dosimeter and provide a safety environment work by maintaining work equipment. Proposes the ongoing training of professionals, emphasizing the relevance of the concepts of radiation protection and the use of the questionnaire with their investigative systematic sequence, which will allow quickly and efficiently the success the investigations

  5. Dosimetric properties of commercial glasses and sand for high doses

    International Nuclear Information System (INIS)

    Teixeira, Maria Ines

    2004-01-01

    Commercial glasses (transparent and colored) produced by Cebrace, Brazil, Sao Paulo, and sand samples of different Brazilian beaches were studied, due to their low cost and easy handling, to verify the possibility of their use in high dose dosimetry. The main dosimetric characteristics were determined using a densitometer, a spectrophotometer, a thermoluminescent (TL) reader and an electronic paramagnetic resonance system. The gamma irradiations were carried out using a Gamma-Cell 220 and a panoramic source ( 60 Co) of IPEN. An optical absorption band was observed at 420 nm in the glass samples. The TL glow curves presented peaks at 205 deg C, 135 deg C, 150 deg C and 145 deg C for the transparent, bronze, brown and green glass samples, respectively. All EPR spectra of the glasses showed Fe 3+ characteristic signals at g = 4.27 and 2.01. The gamma irradiated sand samples presented two peaks at 110 deg C and 170 deg C and an EPR signal at g= 1.999. However, these materials present a pronounced thermal fading at room temperature after irradiation. With the objective to minimize this thermal fading, both glass and sand samples were submitted to different pre- and post-irradiation thermal treatments. The glass and sand samples showed the possibility of utilization for high dose dosimetry and as Yes/No irradiation detectors. (author)

  6. 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)

  7. Audits in high dose rate brachytherapy in Brazil

    International Nuclear Information System (INIS)

    Marechal, M.H.; Rosa, L.A.; Velasco, A.; Paiva, E. de; Goncalves, M.; Castelo, L.C.

    2002-01-01

    The lack of well established dosimetry protocols for HDR sources is a point of great concern regarding the uniformity of procedures within a particular country. The main objective of this paper is to report the results of an implementation of the audit program in dosimetry of high dose rate brachytherapy sources used by the radiation therapy centers in Brazil. In Brazil, among 169 radiotherapy centers, 35 have HDR brachytherapy systems. This program started in August 2001 and until now eight radiotherapy services were audited. The audit program consists of the visit in loco to each center and the evaluation of the intensity of the source with a well type chamber specially design for HDR 192 Ir sources. The measurements was carried out with a HDR1000PLUS Brachytherapy Well Type Chamber and a MAX 4000 Electrometer, both manufactured by Standard Imaging Inc. The chamber was calibrated in air kerma strength by the Accredited Dosimetry Calibration Laboratory, Department of Medical Physics, University of Wisconsin in the USA. The same chamber was calibrated in Brazil using a 192 lr high dose rate source whose intensity was determined by 60 Co gamma rays and 250 kV x rays interpolation methodology. The Nk of 60 Co and 250 kV x rays were provided by the Brazilian National Standard Laboratory for Ionizing Radiation (LMNRI)

  8. Study of the response reduction of LiF:Mg, Ti dosimeter for high dose dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Torkzadeh, Falamarz [Nuclear Sciences and Technology Research Institute, Tehran (Iran, Islamic Republic of). Radiation Applications Research School; AEOI, Tehran (Iran, Islamic Republic of); Faripour, Heidar [Nuclear Sciences and Technology Research Institute, Tehran (Iran, Islamic Republic of). Laser and Optics Research School; AEOI, Tehran (Iran, Islamic Republic of); Mardashti, Forough; Manouchehri, Farhad [Nuclear Sciences and Technology Research Institute, Tehran (Iran, Islamic Republic of). Radiation Applications Research School

    2017-07-15

    A single crystal and 5 polycrystalline samples of LiF:Mg, Ti and their pellets were prepared and investigated so as to apply thermoluminescence high gamma dose dosimetry. Three zones of single crystal with dopant concentrations of 200 ppm of Mg and 20 ppm of Ti were also used to prepare the single crystal samples. For polycrystalline samples, dopant concentrations of 0.062 mol% Mg and Ti concentrations in the range of 0.016 and 0.046 mol% were used. All the samples were exposed to gamma doses of 1 kGy to 700 kGy and their response changes were determined by a gamma dose test of about 60 mGy. According to the results obtained, the use of response reduction by curve-fitting up to about 300 kGy can be performed reliably for high dose gamma dosimetry.

  9. Single-Fraction Carbon-Ion Radiation Therapy for Patients 80 Years of Age and Older With Stage I Non-Small Cell Lung Cancer

    International Nuclear Information System (INIS)

    Karube, Masataka; Yamamoto, Naoyoshi; Nakajima, Mio; Yamashita, Hideomi; Nakagawa, Keiichi; Miyamoto, Tadaaki; Tsuji, Hiroshi; Fujisawa, Takehiko; Kamada, Tadashi

    2016-01-01

    Purpose: In an aging society, many senior citizens want less invasive treatment because of potential medical complications. The National Institute of Radiological Sciences has started to treat stage I lung cancer with single-fraction carbon-ion radiation therapy (CIRT) as a dose escalation prospective phase 1/2 trial. We evaluated the efficacy and safety of CIRT for patients 80 years of age and older, undergoing single-fraction CIRT. Methods and Materials: Peripheral non-small cell lung cancer patients who were treated with single-fraction CIRT were prospectively followed. We analyzed the data from among these patients 80 years of age and older. Results: There were 70 patients. Median age was 83 years (range: 80-89) and median follow-up period was 42.7 months (range: 12-128 months). Three-year local control, cause-specific survival, and overall survival rates were 88.0%, 81.6%, and 72.4%, respectively. Five-year local control, cause-specific survival, and overall survival rates were 85.8%, 64.9%, and 39.7%, respectively. There were no adverse effects higher than grade 2 either in the acute or late phase in terms of skin and lung. Analgesic agents were necessary for only 5 patients (7.1%), to relieve muscular or rib fracture pain caused by irradiation. Conclusions: Single-fraction CIRT was low-risk and effective, even for the elderly.

  10. MRI-guided single fraction ablative radiotherapy for early-stage breast cancer : a brachytherapy versus volumetric modulated arc therapy dosimetry study

    NARCIS (Netherlands)

    Charaghvandi, Ramona K; den Hartogh, Mariska D; van Ommen, Anne-Mar L N; de Vries, Wilfred J H; Scholten, Vincent; Moerland, Rien; Philippens, Mariëlle E P; Schokker, Rogier I; van Vulpen, Marco; van Asselen, B; van den Bongard, Desirée H J G

    2015-01-01

    BACKGROUND AND PURPOSE: A radiosurgical treatment approach for early-stage breast cancer has the potential to minimize the patient's treatment burden. The dosimetric feasibility for single fraction ablative radiotherapy was evaluated by comparing volumetric modulated arc therapy (VMAT) with an

  11. Single-Fraction Carbon-Ion Radiation Therapy for Patients 80 Years of Age and Older With Stage I Non-Small Cell Lung Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Karube, Masataka, E-mail: mstk117@gmail.com [Research Center Hospital for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan); Department of Radiology, The University of Tokyo Hospital, Tokyo (Japan); Yamamoto, Naoyoshi; Nakajima, Mio [Research Center Hospital for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan); Yamashita, Hideomi; Nakagawa, Keiichi [Department of Radiology, The University of Tokyo Hospital, Tokyo (Japan); Miyamoto, Tadaaki; Tsuji, Hiroshi [Research Center Hospital for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan); Fujisawa, Takehiko [Chiba Foundation for Health Promotion and Disease Prevention, Chiba (Japan); Kamada, Tadashi [Research Center Hospital for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan)

    2016-05-01

    Purpose: In an aging society, many senior citizens want less invasive treatment because of potential medical complications. The National Institute of Radiological Sciences has started to treat stage I lung cancer with single-fraction carbon-ion radiation therapy (CIRT) as a dose escalation prospective phase 1/2 trial. We evaluated the efficacy and safety of CIRT for patients 80 years of age and older, undergoing single-fraction CIRT. Methods and Materials: Peripheral non-small cell lung cancer patients who were treated with single-fraction CIRT were prospectively followed. We analyzed the data from among these patients 80 years of age and older. Results: There were 70 patients. Median age was 83 years (range: 80-89) and median follow-up period was 42.7 months (range: 12-128 months). Three-year local control, cause-specific survival, and overall survival rates were 88.0%, 81.6%, and 72.4%, respectively. Five-year local control, cause-specific survival, and overall survival rates were 85.8%, 64.9%, and 39.7%, respectively. There were no adverse effects higher than grade 2 either in the acute or late phase in terms of skin and lung. Analgesic agents were necessary for only 5 patients (7.1%), to relieve muscular or rib fracture pain caused by irradiation. Conclusions: Single-fraction CIRT was low-risk and effective, even for the elderly.

  12. Online Coupling of Flow-Field Flow Fractionation and Single Particle Inductively Coupled Plasma-Mass Spectrometry: Characterization of Nanoparticle Surface Coating Thickness and Aggregation State

    Science.gov (United States)

    Surface coating thickness and aggregation state have strong influence on the environmental fate, transport, and toxicity of engineered nanomaterials. In this study, flow-field flow fractionation coupled on-line with single particle inductively coupled plasma-mass spectrometry i...

  13. Early and late effects of local high dose radiotherapy of the brain on memory and attention

    International Nuclear Information System (INIS)

    Duchstein, S.; Gademann, G.; Peters, B.

    2003-01-01

    Early and Late Effects of Local High Dose Radiotherapy of the Brain on Memory and Attention Background: Stereotactic radiotherapy of benign tumors of the base of skull shows excellent tumor control and long survival. Aim is to study the impact of high dose radiation therapy on functions of memory and attention over time. Patients and Methods: 21 patients (age 42 ± 11 years) with tumors of the base of skull (meningiomas, pituitary gland adenomas) were treated by fractionated stereotactic radiotherapy (mean total dose 56,6 Gy/1,8 Gy). Comprehensive neuropsychological tests and MRI brain scans were performed before, 3, 9 and 21 months after therapy. 14 healthy volunteers were tested in parallel at baseline. In the follow-ups patients were their own controls. Results: In pretreatment tests there were significantly worse test results in comparison to the control group in ten of 32 tests. In postradiation tests only few changes were found in the early-delayed period and not much difference was seen in comparison to the baseline tests. In MRI scans tumor recurrences or radiation induced changes were not found. Conclusion: Radiation with high local doses in target volume extremely close to sensitive brain structures like temporal lobes did not induce significant decline of cognitive functions. (orig.) [de

  14. High-dose-rate brachytherapy using molds for oral cavity cancer. The technique and its limitations

    International Nuclear Information System (INIS)

    Nishimura, Yasumasa; Yokoe, Yoshihiko; Nagata, Yasushi; Okajima, Kaoru; Nishida, Mitsuo; Hiraoka, Masahiro

    1998-01-01

    With the availability of a high-dose-rate (HDR) remote afterloading device, a Phase I/II protocol was initiated at our institution to assess the toxicity and efficacy of HDR intracavitary brachytherapy, using molds, in the treatment of squamous cell carcinomas of the oral cavity. Eight patients with squamous cell carcinoma of the oral cavity were treated by the technique. The primary sites of the tumors were the buccal mucosa, oral floor, and gingiva. Two of the buccal mucosal cancers were located in the retromolar trigon. For each patient, a customized mold was fabricated, in which two to four afterloading catheters were placed for an 192 Ir HDR source. Four to seven fractions of 3-4 Gy, 5 mm below the mold surface, were given following external radiation therapy of 40-60 Gy/ 2 Gy. The total dose of HDR brachytherapy ranged from 16 to 28Gy. Although a good initial complete response rate of 7/8 (88%) was achieved, there was local recurrence in four of these seven patients. Both of the retromolar trigon tumors showed marginal recurrence. No serious (e.g., ulcer or bone exposure) late radiation damage has been observed thus far in the follow up period of 15-57 months. High-dose-rate brachytherapy using the mold technique seems a safe and useful method for selected early and superficial oral cavity cancer. However, it is not indicated for thick tumors and/or tumors located in the retromolar trigon. (author)

  15. Fractionated vs. single-fraction stereotactic radiotherapy in patients with vestibular schwannoma. Hearing preservation and patients' self-reported outcome based on an established questionnaire

    International Nuclear Information System (INIS)

    Kessel, Kerstin A.; Fischer, Hanna; Vogel, Marco M.E.; Combs, Stephanie E.; Oechsner, Markus; Bier, Henning; Meyer, Bernhard

    2017-01-01

    Stereotactic radiotherapy (RT) has been established as a valid treatment alternative in patients with vestibular schwannoma (VS). There is ongoing controversy regarding the optimal fractionation. Hearing preservation may be the primary goal for patients with VS, followed by maintenance of quality of life (QoL). From 2002 to 2015, 184 patients with VS were treated with radiosurgery (RS) or fractionated stereotactic radiotherapy (FSRT). A survey on current symptoms and QoL was conducted between February and June 2016. Median follow-up after RT was 7.5 years (range 0-14.4 years). Mean overall survival (OS) after RT was 31.1 years, with 94 and 87% survival at 5 and 10 years, respectively. Mean progression-free survival (PFS) was 13.3 years, with 5- and 10-year PFS of 92%. Hearing could be preserved in RS patients for a median of 36.3 months (range 2.3-13.7 years). Hearing worsened in 17 (30%) cases. Median hearing preservation for FSRT was 48.7 months (range 0.0-13.8 years); 29 (23%) showed hearing deterioration. The difference in hearing preservation was not significant between RS and FSRT (p = 0.3). A total of 123/162 patients participated in the patient survey (return rate 76%). The results correlate well with the information documented in the patient files for tinnitus and facial and trigeminal nerve toxicity. Significant differences appeared regarding hearing impairment, gait uncertainty, and imbalance. These data confirm that RS and FSRT are comparable in terms of local control for VS. RS should be reserved for smaller lesions, while FSRT can be offered independently of tumor size. Patient self-reported outcome during follow-up is of high value. The established questionnaire could be validated in the independent cohort. (orig.) [de

  16. Stock selection of high-dose-irradiation-resistant materials for filter press under high-dose irradiation operation

    International Nuclear Information System (INIS)

    Ishiyama, Shintaro; Minami, Mamoru; Hara, Kouji; Yamashita, Manabu

    2015-01-01

    In a volume reduction process for the decontamination of contained soil, the performance degradation of a filter press is expected owing to material deterioration under high-dose irradiation. Eleven-stock selection of candidate materials including polymers, fibers and rubbers for the filter press was conducted to achieve a high performance of volume reduction of contaminated soil and the following results were derived. Crude rubber and nylon were selected as prime candidates for packing, diaphragm and filter plate materials. Polyethylene was also selected as a prime candidate for the filter cloth material. (author)

  17. In vivo assessment of the tolerance dose of small liver volumes after single-fraction HDR irradiation

    International Nuclear Information System (INIS)

    Ricke, Jens; Seidensticker, Max; Luedemann, Lutz; Pech, Maciej; Wieners, Gero; Hengst, Susanne; Mohnike, Konrad; Cho, Chie Hee; Lopez Haenninen, Enrique; Al-Abadi, Hussain; Felix, Roland; Wust, Peter

    2005-01-01

    Purpose: To prospectively assess a dose-response relationship for small volumes of liver parenchyma after single-fraction irradiation. Methods and Materials: Twenty-five liver metastases were treated by computed tomography (CT)-guided interstitial brachytherapy. Magnetic resonance imaging was performed 1 day before and 3 days and 6, 12, and 24 weeks after therapy. MR sequences included T1-w gradient echo (GRE) enhanced by hepatocyte-targeted gadobenate dimeglumine. All MRI data sets were merged with 3D dosimetry data and evaluated by two radiologists. The reviewers indicated the border of hyperintensity on T2-w images (edema) or hypointensity on T1-w images (loss of hepatocyte function). Based on the total 3D data, a dose-volume histogram was calculated. We estimated the threshold dose for either edema or function loss as the D 90 , i.e., the dose achieved in at least 90% of the pseudolesion volume. Results: Between 3 days and 6 weeks, the extension of the edema increased significantly from the 12.9 Gy isosurface to 9.9 Gy (standard deviation [SD], 3.3 and 2.6). No significant change was detected between 6 and 12 weeks. After 24 weeks, the edematous tissue had shrunk significantly to 14.7 Gy (SD, 4.2). Three days postbrachytherapy, the D 90 for hepatocyte function loss reached the 14.9 Gy isosurface (SD, 3.9). At 6 weeks, the respective zone had increased significantly to 9.9 Gy (SD, 2.3). After 12 and 24 weeks, the dysfunction volume had decreased significantly to the 11.9 Gy and 15.2 Gy isosurface, respectively (SD, 3 and 4.1). Conclusions: The 95% interval from 7.6 to 12.2 Gy found as the minimal hepatocyte tolerance after 6 weeks accounts for the radiobiologic variations found in CT-guided brachytherapy, including heterogeneous dose rates by variable catheter arrays

  18. 3D quantitative assessment of response to fractionated stereotactic radiotherapy and single-session stereotactic radiosurgery of vestibular schwannoma

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, T. [The Johns Hopkins Hospital School of Medicine, Russell H. Morgan Department of Radiology and Radiological Sciences, Division of Neuroradiology, Baltimore, MD (United States); University Medical Center Hamburg-Eppendorf, Department of Diagnostic and Interventional Neuroradiology, Hamburg (Germany); Chapiro, J. [The Johns Hopkins Hospital School of Medicine, Russell H. Morgan Department of Radiology and Radiological Sciences, Division of Interventional Radiology, Baltimore, MD (United States); Lin, M. [Philips Research North America, Ultrasound Imaging and Interventions (UII), Briarcliff Manor, NY (United States); Geschwind, J.F. [The Johns Hopkins Hospital School of Medicine, Russell H. Morgan Department of Radiology and Radiological Sciences, Division of Interventional Radiology, Baltimore, MD (United States); Yale University School of Medicine, Department of Radiology and Imaging Science, New Haven, CT (United States); Kleinberg, L. [The Johns Hopkins University School of Medicine, Department of Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD (United States); Rigamonti, D.; Jusue-Torres, I.; Marciscano, A.E. [The Johns Hopkins University School of Medicine, Department of Neurological Surgery, Baltimore, MD (United States); Yousem, D.M. [The Johns Hopkins Hospital School of Medicine, Russell H. Morgan Department of Radiology and Radiological Sciences, Division of Neuroradiology, Baltimore, MD (United States)

    2016-03-15

    To determine clinical outcome of patients with vestibular schwannoma (VS) after treatment with fractionated stereotactic radiotherapy (FSRT) and single-session stereotactic radiosurgery (SRS) by using 3D quantitative response assessment on MRI. This retrospective analysis included 162 patients who underwent radiation therapy for sporadic VS. Measurements on T1-weighted contrast-enhanced MRI (in 2-year post-therapy intervals: 0-2, 2-4, 4-6, 6-8, 8-10, 10-12 years) were taken for total tumour volume (TTV) and enhancing tumour volume (ETV) based on a semi-automated technique. Patients were considered non-responders (NRs) if they required subsequent microsurgical resection or developed radiological progression and tumour-related symptoms. Median follow-up was 4.1 years (range: 0.4-12.0). TTV and ETV decreased for both the FSRT and SRS groups. However, only the FSRT group achieved significant tumour shrinkage (p < 0.015 for TTV, p < 0.005 for ETV over time). The 11 NRs showed proportionally greater TTV (median TTV pre-treatment: 0.61 cm{sup 3}, 8-10 years after: 1.77 cm{sup 3}) and ETV despite radiation therapy compared to responders (median TTV pre-treatment: 1.06 cm{sup 3}; 10-12 years after: 0.81 cm{sup 3}; p = 0.001). 3D quantification of VS showed a significant decrease in TTV and ETV on FSRT-treated patients only. NR had significantly greater TTV and ETV over time. (orig.)

  19. Single-centre experience of stereotactic radiosurgery and fractionated stereotactic radiotherapy for prolactinomas with the linear accelerator.

    Science.gov (United States)

    Wilson, Peter J; Williams, Janet Rosemary; Smee, Robert Ian

    2015-06-01

    Primary management of prolactinomas is usually medical, with surgery a secondary option where necessary. This study is a review of a single centre's experience with focused radiotherapy where benefit was not gained by medical or surgical approaches. Radiotherapy as an alternative and adjuvant treatment for prolactinomas has been performed at our institution with the linear accelerator since 1990. We present a retrospective review of 13 patients managed with stereotactic radiosurgery (SRS) and 5 managed with fractionated stereotactic radiotherapy (FSRT), as well as 5 managed with conventional radiotherapy, at the Prince of Wales Hospital. Patients with a histopathologically diagnosed prolactinoma were eligible. Those patients who had a confirmed pathological diagnosis of prolactinoma following surgical intervention, a prolactin level elevated above 500 μg/L, or a prolactin level persistently elevated above 200 μg/L with exclusion of other causes were represented in this review. At the end of documented follow-up (SRS median 6 years, FSRT median 2 years), no SRS patients showed an increase in tumour volume. After FSRT, 1 patient showed an increase in size, 2 showed a decrease in size and 2 patients showed no change. Prolactin levels trended towards improvement after SRS and FSRT, but no patients achieved the remission level of <20 μg/L. Seven of 13 patients in the SRS group achieved a level of <500 μg/L, whereas no patients reached this target after FSRT. A reduction in prolactin level is frequent after SRS and FSRT for prolactinomas; however, true biochemical remission is uncommon. Tumour volume control in this series was excellent, but this may be related to the natural history of the disease. Morbidity and mortality after stereotactic radiation were very low in this series. © 2014 The Royal Australian and New Zealand College of Radiologists.

  20. New method for single-breath fraction of exhaled nitric oxide measurement with improved feasibility in preschool children with asthma.

    Science.gov (United States)

    Heijkenskjöld-Rentzhog, Charlotte; Kalm-Stephens, Pia; Nordvall, Lennart; Malinovschi, Andrei; Alving, Kjell

    2015-11-01

    Respiratory societies recommend use of standardized methodologies for fraction of exhaled nitric oxide (FeNO) measurements in adults and children, but in preschoolers, feasibility remains a problem. The exhalation time needed to obtain steady-state FeNO is unclear. Our primary aim was to study the feasibility of an adapted single-breath FeNO method with age-adjusted exhalation times. We also studied the association between time to steady-state NO level and height, as well as FeNO in relation to asthma and current treatment with inhaled corticosteroids (ICS). Sixty-three children aged 3-10 years performed FeNO measurements with a hand-held electrochemical device with a newly developed flow-control unit. Exhalation times were pre-adapted to age. Exhaled air was simultaneously sampled to a chemiluminescence analyzer to measure time to steady-state NO level. Eighty-one percent of the children achieved at least one approved measurement. From 4 years upwards, success rate was high (96%). Time to steady-state [NO] (median and interquartile range) was 2.5 s (2.4-3.5) at the age of 3-4 years and 3.5 s (2.7-3.8) at the age of 5-6 years. Height was associated with time to steady state (r(2) = 0.13, p = 0.02). FeNO (geometric mean [95% CI]) was higher in ICS-naïve asthmatic children (n = 19): 15.9 p.p.b. (12.2-20.9), than in both healthy controls (n = 8) 9.1 p.p.b. (6.6-12.4) and asthmatic subjects on treatment (n = 24) 11.5 p.p.b. (9.7-13.6). We found this adapted single-breath method with age-adjusted exhalation times highly feasible for children aged 4-10 years. ICS-naïve asthmatic children had FeNO levels under the current guideline cutoff level (20 p.p.b.), highlighting the importance of taking age into account when setting reference values. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

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

    International Nuclear Information System (INIS)

    Barkati, Maroie; Williams, Scott G.; Foroudi, Farshad; Tai, Keen Hun; Chander, Sarat; Dyk, Sylvia van; See, Andrew; Duchesne, Gillian M.

    2012-01-01

    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

  2. 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

  3. Dose escalation using conformal high-dose-rate brachytherapy improves outcome in unfavorable prostate cancer

    International Nuclear Information System (INIS)

    Martinez, Alvaro A.; Gustafson, Gary; Gonzalez, Jose; Armour, Elwood; Mitchell, Chris; Edmundson, Gregory; Spencer, William; Stromberg, Jannifer; Huang, Raywin; Vicini, Frank

    2002-01-01

    Purpose: To overcome radioresistance for patients with unfavorable prostate cancer, a prospective trial of pelvic external beam irradiation (EBRT) interdigitated with dose-escalating conformal high-dose-rate (HDR) prostate brachytherapy was performed. Methods and Materials: Between November 1991 and August 2000, 207 patients were treated with 46 Gy pelvic EBRT and increasing HDR brachytherapy boost doses (5.50-11.5 Gy/fraction) during 5 weeks. The eligibility criteria were pretreatment prostate-specific antigen level ≥10.0 ng/mL, Gleason score ≥7, or clinical Stage T2b or higher. Patients were divided into 2 dose levels, low-dose biologically effective dose 93 Gy (149 patients). No patient received hormones. We used the American Society for Therapeutic Radiology and Oncology definition for biochemical failure. Results: The median age was 69 years. The mean follow-up for the group was 4.4 years, and for the low and high-dose levels, it was 7.0 and 3.4 years, respectively. The actuarial 5-year biochemical control rate was 74%, and the overall, cause-specific, and disease-free survival rate was 92%, 98%, and 68%, respectively. The 5-year biochemical control rate for the low-dose group was 52%; the rate for the high-dose group was 87% (p<0.001). Improvement occurred in the cause-specific survival in favor of the brachytherapy high-dose level (p=0.014). On multivariate analysis, a low-dose level, higher Gleason score, and higher nadir value were associated with increased biochemical failure. The Radiation Therapy Oncology Group Grade 3 gastrointestinal/genitourinary complications ranged from 0.5% to 9%. The actuarial 5-year impotency rate was 51%. Conclusion: Pelvic EBRT interdigitated with transrectal ultrasound-guided real-time conformal HDR prostate brachytherapy boost is both a precise dose delivery system and a very effective treatment for unfavorable prostate cancer. We demonstrated an incremental beneficial effect on biochemical control and cause

  4. High Doses Gamma Radiolysis of PVC: Mechanisms of Degradation

    International Nuclear Information System (INIS)

    Colombani, J.

    2006-01-01

    PVC radiolysis leads to the formation of various degradation products: radicals, gas, oxidized products or polyenes. In order to predict the formation of the degradation products with regard to irradiation and ageing parameters, it is important to improve the understanding of the radiolysis mechanisms of PVC. Thus, we used several analytical techniques (Electron Spin Resonance, Fourier Transform Infrared spectroscopy, Nuclear Magnetic Resonance, Size Exclusion Chromatography) to get information on PVC samples irradiated at high doses (up to 4MGy) under different conditions. Gamma irradiation induces the formation of various radicals into PVC. Older studies were generally focused on the effect of low dose and/or low temperature irradiations on PVC. We present here ESR signals of PVC irradiated at high doses and at room temperature. We show that peroxyl radicals are producted by radiolysis under aerobe conditions and that polyenyl radicals are formed under anaerobe conditions. PVC radiolysis induces gas production and especially hydrogen chloride. Production of hydrogen chloride is well known until 1 MGy. We have studied by FTIR, the evolution of the quantity of HCl produced until 4 MGy. We show that higher irradiation dose leads to the lower radiolytic yield of HCl (G(HCl)). Moreover, G(HCl) obtained in aerobe conditions is about fourfold as great as G(HCl) observed in anaerobe radiolysis. Propagation and termination reactions induce degradation products: polyene sequences and crosslinking reactions are observed under anaerobe conditions; oxidized products with addition of chain scissions are formed under aerobe conditions. Although the literature about PVC radiolysis is rich, the main reacting pathways are not well established. Moreover the high doses studies are almost non-existent. We show by FTIR that aerobe radiolysis induces formation of ketons and acids. NMR experiments confirme these results but also focuse on small acids formed (with 2, 3 or 4 carbons). The

  5. High-dose radioiodine therapy of Graves disease

    International Nuclear Information System (INIS)

    Solodky, V.; Fomin, D.; Pestritskaya, E.

    2015-01-01

    Full text of publication follows. Objectives: to estimate the effectiveness and safety of the disease treatment under different modes of applying RIT. Materials and methods: 67 patients with the thyrotoxicosis condition associated with Graves disease were researched. The patients were divided into 2 groups: a control group with 25 people (18 women and 7 men), who underwent a low-dose therapy of 150-500 MBq; and a main group of 42 people (32 women and 10 men), who underwent a high-dose therapy of 550 and 800 MBq. The volume of thyroid prior to the treatment made up 23.8 ± 20 ml in the main group and 30.2 ± 23 ml in the control one. The average age in the high-dose group was 44.6 ±23 years old and in the low-dose -47.2 ± 24 years old. In terms of the hormone level before the RIT, 52% of the main group patients experienced euthyroidism, while 48% - thyrotoxicosis. The corresponding indices in the control group were 42% and 58% respectively. The cessation of the thyreostatic therapy came on 5. to 21. day prior to the treatment, with the average of 14 ±7 days in both groups. The diagnosis of the disease was based on ultrasonography, planar scintigraphy, the hormone level and antibody titer. The performance was assessed through the attainment of hypo-thyrosis and the transition to a substitutive hormonal therapy with L-thyroxine in 6 months or more. The attainment of euthyroidism was seen as a partial effect due to a possibility of relapse. Results: in 6 months a positive result in the form of hypo-thyrosis was achieved for 39 patients in the main group, which accounted for 93%, and 3 patients (7%) experienced euthyroidism. No symptomatic thyrotoxicosis relapses were revealed. In the control group, hypo-thyrosis was achieved by 18 patients, which accounted for 72%; euthyroidism came up to 12%; 4 patients needed a refresher course of RIT, which made up 16% of the group. 93% of the main group patients tolerated the treatment favourably. 3 patients complained of the

  6. Effects of local single and fractionated X-ray doses on rat bone marrow blood flow and red blood cell volume

    International Nuclear Information System (INIS)

    Pitkaenen, M.A.; Hopewell, J.W.

    1985-01-01

    Time and dose dependent changes in blood flow and red blood cell volume were studied in the locally irradiated bone marrow of the rat femur after single and fractionated doses of X-rays. With the single dose of 10 Gy the bone marrow blood flow although initially reduced returned to the control levels by seven months after irradiation. With doses >=15 Gy the blood flow was still significantly reduced at seven months. The total dose levels predicted by the nominal standard dose equation for treatments in three, six or nine fractions produced approximately the same degree of reduction in the bone marrow blood flow seven months after the irradiation. However, the fall in the red blood cell volume was from 23 to 37% greater in the three fractions groups compared with that in the nine fractions groups. Using the red blood cell volume as a parameter the nominal standard dose formula underestimated the severity of radiation damage in rat bone marrow at seven months for irradiation with small numbers of large dose fractions. (orig.) [de

  7. Routine quality control of high dose rate brachytherapy equipment

    International Nuclear Information System (INIS)

    Guzman Calcina, Carmen S.; Almeida, Adelaide de; Rocha, Jose R. Oliveira

    2001-01-01

    A Quality Assurance program should be installed also for High Dose Rate brachytherapy, in the order to achieve a correct dose administration to the patient and for the safety to those involved directly with the treatment. The work presented here has the following purposes: Analyze the types of equipment tests presented by the official protocols (TG40, TG56 e ARCAL XXX), evaluate the brachytherapy routine tests of protocols from various national and international radiotherapy services and compare the latter with those presented in the official protocols. As a result, we conclude the following: TG56 presents a higher number of tests when compared to the other official protocols and most of the tests presented by the analyzed services are present in TG56. A suggestion for a basic protocol is presented, emphasizing the periodicity and tolerance level of each of the tests. (author)

  8. measurement of high dose radiation using yellow perspex dosimeter

    International Nuclear Information System (INIS)

    Thamrin, M Thoyib; Sofyan, Hasnel

    1996-01-01

    Measurement of high dose radiation using yellow perspex dosemeter has been carried out. Dose range used was between 0.1 to 3.0 kGy. Measurement of dose rate against Fricke dosemeter as a standard dose meter From the irradiation of Fricke dosemeter with time variation of 3,6,9,12,15 and 18 minute, it was obtained average dose rate of 955.57 Gy/hour, linear equation of dose was Y= 2.333+15.776 X with its correlation factor r = 0.9999. Measurement result using yellow perspex show that correlation between net optical density and radiation dose was not linear with its equation was ODc exp. [Bo + In(dose).Bi] Value of Bo = -0.215 and Bi=0.5020. From the experiment it was suggested that routine dosimeter (yellow perspex) should be calibrated formerly against standard dosemeters

  9. High Fidelity Ion Beam Simulation of High Dose Neutron Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Was, Gary; Wirth, Brian; Motta, Athur; Morgan, Dane; Kaoumi, Djamel; Hosemann, Peter; Odette, Robert

    2018-04-30

    Project Objective: The objective of this proposal is to demonstrate the capability to predict the evolution of microstructure and properties of structural materials in-reactor and at high doses, using ion irradiation as a surrogate for reactor irradiations. “Properties” includes both physical properties (irradiated microstructure) and the mechanical properties of the material. Demonstration of the capability to predict properties has two components. One is ion irradiation of a set of alloys to yield an irradiated microstructure and corresponding mechanical behavior that are substantially the same as results from neutron exposure in the appropriate reactor environment. Second is the capability to predict the irradiated microstructure and corresponding mechanical behavior on the basis of improved models, validated against both ion and reactor irradiations and verified against ion irradiations. Taken together, achievement of these objectives will yield an enhanced capability for simulating the behavior of materials in reactor irradiations

  10. Safety handling manual for high dose rate remote afterloading system

    International Nuclear Information System (INIS)

    1999-01-01

    This manual is mainly for safety handling of 192 Ir-RALS (remote afterloading system) of high dose rate and followings were presented: Procedure and document format for the RALS therapy and for handling of its radiation source with the purpose of prevention of human errors and unexpected accidents, Procedure for preventing errors occurring in the treatment schedule and operation, and Procedure and format necessary for newly introducing the system into a facility. Consistency was intended in the description with the quality assurance guideline for therapy with small sealed radiation sources made by JASTRO (Japan Society for Therapeutic Radiology and Oncology). Use of the old type 60 Co-RALS was pointed out to be a serious problem remained and its safety handling procedure was also presented. (K.H.)

  11. 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, 60......, 120, 180, 240, 300, 360, and 420 minutes after the bolus. Quantitative determination of plasma melatonin concentrations was performed using a radioimmunoassay technique. Pharmacokinetic parameters were estimated by a compartmental pharmacokinetic analysis. Adverse effects included assessments...... of sedation and registration of other symptoms. Sedation, evaluated as simple reaction times, was measured at baseline and 120, 180, 300, and 420 minutes after the bolus. Twelve male volunteers completed the study. Median (IQR) Cmax after the bolus injections of 10 mg and 100 mg of melatonin were 221...

  12. Calibration of {sup 192}Ir high dose rate brachytherapy sources

    Energy Technology Data Exchange (ETDEWEB)

    Marechal, M H [Instituto de Radioprotecao e Dozimetria, Rio de Jainero (Brazil); Almeida, C.E. de [Laboratorio de Ciencias Radiologicas, UERL, Rio de Janeiro (Brazil); Sibata, C H [Roswell Park Cancer Inst., Buffalo, NY (United States)

    1996-08-01

    A method for calibration of high dose rate sources used in afterloading brachytherapy systems is described. The calibration for {sup 192}Ir is determined by interpolating {sup 60}Co gamma-rays and 250 kV x-rays calibration factors. All measurements were done using the same build up caps as described by Goetsch et al and recommended by AAPM. The attenuation correction factors were determined to be 0.9903, 0.9928 and 0.9993 for {sup 192}Ir, {sup 60}Co and 250 kV x-ray, respectively. A wall + cap thickness of 0.421 g.cm{sup -2} is recommended for all measurements to ensure electronic equilibrium for {sup 60}Co and {sup 192}Ir gamma-ray beams. A mathematical formalism is described for determination of (N{sub x}){sub Ir}. (author). 5 refs, 1 fig.

  13. Assessments for high dose radionuclide therapy treatment planning

    International Nuclear Information System (INIS)

    Fisher, D.R.

    2003-01-01

    Advances in the biotechnology of cell specific targeting of cancer and the increased number of clinical trials involving treatment of cancer patients with radiolabelled antibodies, peptides, and similar delivery vehicles have led to an increase in the number of high dose radionuclide therapy procedures. Optimised radionuclide therapy for cancer treatment is based on the concept of absorbed dose to the dose limiting normal organ or tissue. The limiting normal tissue is often the red marrow, but it may sometimes be the lungs, liver, intestinal tract, or kidneys. Appropriate treatment planning requires assessment of radiation dose to several internal organs and tissues, and usually involves biodistribution studies in the patient using a tracer amount of radionuclide bound to the targeting agent and imaged at sequential timepoints using a planar gamma camera. Time-activity curves are developed from the imaging data for the major organ tissues of concern, for the whole body and sometimes for selected tumours. Patient specific factors often require that dose estimates be customised for each patient. In the United States, the Food and Drug Administration regulates the experimental use of investigational new drugs and requires 'reasonable calculation of radiation absorbed dose to the whole body and to critical organs' using the methods prescribed by the Medical Internal Radiation Dose (MIRD) Committee of the Society of Nuclear Medicine. Review of high dose studies shows that some are conducted with minimal dosimetry, that the marrow dose is difficult to establish and is subject to large uncertainties. Despite the general availability of software, internal dosimetry methods often seem to be inconsistent from one clinical centre to another. (author)

  14. High Dose Cyclophosphamide without Stem Cell Rescue in 207 Patients with Aplastic anemia and other Autoimmune Diseases

    Science.gov (United States)

    DeZern, Amy E.; Petri, Michelle; Drachman, Daniel B.; Kerr, Doug; Hammond, Edward R.; Kowalski, Jeanne; Tsai, Hua-Ling; Loeb, David M.; Anhalt, Grant; Wigley, Fredrick; Jones, Richard J.; Brodsky, Robert A.

    2011-01-01

    High-dose cyclophosphamide has long been used an anticancer agent, a conditioning regimen for hematopoietic stem cell transplantation and as potent immunosuppressive agent in autoimmune diseases including aplastic anemia. High-dose cyclophosphamide is highly toxic to lymphocytes but spares hematopoietic stem cells because of their abundant levels of aldehyde dehydrogenase, the major mechanism of cyclophosphamide inactivation. High dose cyclophosphamide therapy induces durable remissions in most patients with acquired aplastic anemia. Moreover, high-dose cyclophosphamide without hematopoietic stem cell rescue has shown activity in a variety of other severe autoimmune diseases. Here we review the history of cyclophosphamide as is applies to aplastic anemia (AA) and other autoimmune diseases. Included here are the historical data from early patients treated for AA as well as an observational retrospective study in a single tertiary care hospital. This latter component was designed to assess the safety and efficacy of high-dose cyclophosphamide therapy without stem cell rescue in patients with refractory autoimmune diseases. We analyzed fully the 140 patients with severe, progressive autoimmune diseases treated. All patients discussed here received cyclophosphamide, 50 mg/kg per day for 4 consecutive days. Response, relapse and overall survival were measured. Response was defined as a decrease in disease activity in conjunction with a decrease or elimination of immune modulating drugs. Relapse was defined as worsening disease activity and/or a requirement of an increase in dose of, or administration of new, immunosuppressive medications. Hematologic recovery occurred in all patients. The overall response rate of the was 95%, and 44% of those patients remain progression-free with a median follow up time of 36 (range 1–120) months for the 140 patients analyzed together. The overall actuarial and event free survival across all diseases at 60 months is 90.7% and 20

  15. Fractionated vs. single-fraction stereotactic radiotherapy in patients with vestibular schwannoma. Hearing preservation and patients' self-reported outcome based on an established questionnaire

    Energy Technology Data Exchange (ETDEWEB)

    Kessel, Kerstin A.; Fischer, Hanna; Vogel, Marco M.E.; Combs, Stephanie E. [Technical University of Munich (TUM), Department of Radiation Oncology, Munich (Germany); Helmholtz Zentrum Muenchen, Institute of Innovative Radiotherapy (iRT), Neuherberg (Germany); Oechsner, Markus [Technical University of Munich (TUM), Department of Radiation Oncology, Munich (Germany); Bier, Henning [Technical University of Munich (TUM), Department of Otorhinolaryngology, Munich (Germany); Meyer, Bernhard [Technical University of Munich (TUM), Department of Neurosurgery, Munich (Germany)

    2017-03-15

    Stereotactic radiotherapy (RT) has been established as a valid treatment alternative in patients with vestibular schwannoma (VS). There is ongoing controversy regarding the optimal fractionation. Hearing preservation may be the primary goal for patients with VS, followed by maintenance of quality of life (QoL). From 2002 to 2015, 184 patients with VS were treated with radiosurgery (RS) or fractionated stereotactic radiotherapy (FSRT). A survey on current symptoms and QoL was conducted between February and June 2016. Median follow-up after RT was 7.5 years (range 0-14.4 years). Mean overall survival (OS) after RT was 31.1 years, with 94 and 87% survival at 5 and 10 years, respectively. Mean progression-free survival (PFS) was 13.3 years, with 5- and 10-year PFS of 92%. Hearing could be preserved in RS patients for a median of 36.3 months (range 2.3-13.7 years). Hearing worsened in 17 (30%) cases. Median hearing preservation for FSRT was 48.7 months (range 0.0-13.8 years); 29 (23%) showed hearing deterioration. The difference in hearing preservation was not significant between RS and FSRT (p = 0.3). A total of 123/162 patients participated in the patient survey (return rate 76%). The results correlate well with the information documented in the patient files for tinnitus and facial and trigeminal nerve toxicity. Significant differences appeared regarding hearing impairment, gait uncertainty, and imbalance. These data confirm that RS and FSRT are comparable in terms of local control for VS. RS should be reserved for smaller lesions, while FSRT can be offered independently of tumor size. Patient self-reported outcome during follow-up is of high value. The established questionnaire could be validated in the independent cohort. (orig.) [German] Die stereotaktische Radiotherapie (RT) wurde als gueltige Behandlungsalternative bei Patienten mit Vestibularisschwannom (VS) etabliert. Diskussionen ueber die optimale Fraktionierung laufen jedoch. Der Erhalt von Hoervermoegen

  16. Detection and characterization of silver nanoparticles in chicken meat by asymmetric flow field flow fractionation with detection by conventional or single particle ICP-MS

    DEFF Research Database (Denmark)

    Löschner, Katrin; Navratilova, Jana; Købler, Carsten

    2013-01-01

    of the AgNPs took place during the sample preparation stage. The digestate was injected into the asymmetric flow field flow fractionation (AF(4)) -ICP-MS system, which enabled fractionation of nanoparticles from the remaining meat matrix, and resulted in one large peak in the fractograms as well as two...... smaller peaks eluting close to the void volume. The recovery of silver contained in the large AgNP peak was around 80 %. Size determination of AgNPs in the meat matrix, based on external size calibration of the AF(4) channel, was hampered by non-ideal (early elution) behavior of the AgNPs. Single particle...

  17. Better compliance with hypofractionation vs. conventional fractionation in adjuvant breast cancer radiotherapy. Results of a single, institutional, retrospective study

    International Nuclear Information System (INIS)

    Rudat, Volker; Nour, Alaa; Hammoud, Mohamed; Abou Ghaida, Salam

    2017-01-01

    The aim of the study was to identify factors significantly associated with the occurrence of unintended treatment interruptions in adjuvant breast cancer radiotherapy. Patients treated with postoperative radiotherapy of the breast or chest wall between March 2014 and August 2016 were evaluated. The radiotherapy regimens and techniques applied were either conventional fractionation (CF; 28 daily fractions of 1.8 Gy or 25 fractions of 2.0 Gy) or hypofractionation (HF; 15 daily fractions of 2.67 Gy) with inverse planned intensity-modulated radiotherapy (IMRT) or three-dimensional planned conformal radiotherapy (3DCRT). Logistic regression analysis was used to identify factors associated with noncompliance. Noncompliance was defined as the missing of at least one scheduled radiotherapy fraction. In all, 19 of 140 (13.6%) patients treated with HF and 39 of 146 (26.7%) treated with CF experienced treatment interruptions. Of 23 factors tested, the fractionation regimen emerged as the only independent significant prognostic factor for noncompliance on multivariate analysis (CF; p = 0.007; odds ratio, 2.3; 95% confidence interval, 1.3-4.2). No statistically significant differences concerning the reasons for treatment interruptions could be detected between patients treated with CF or HF. HF is significantly associated with a better patient compliance with the prescribed radiotherapy schedule compared with CF. The data suggest that this finding is basically related to the shorter overall treatment time of HF. (orig.) [de

  18. Acute cognitive effects of high doses of dextromethorphan relative to triazolam in humans

    Science.gov (United States)

    Carter, Lawrence P.; Reissig, Chad J.; Johnson, Matthew W.; Klinedinst, Margaret A.; Griffiths, Roland R.

    2012-01-01

    BACKGROUND Although concerns surrounding high-dose dextromethorphan (DXM) abuse have recently increased, few studies have examined the acute cognitive effects of high doses of DXM. The aim of this study was to compare the cognitive effects of DXM with those of triazolam and placebo. METHODS Single, acute, oral doses of DXM (100, 200, 300, 400, 500, 600, 700, 800 mg/70 kg), triazolam (0.25, 0.5 mg /70 kg), and placebo were administered p.o. to twelve healthy volunteers with histories of hallucinogen use, under double-blind conditions, using an ascending dose run-up design. Effects on cognitive performance were examined at baseline and after drug administration for up to 6 hours. RESULTS Both triazolam and DXM produced acute impairments in attention, working memory, episodic memory, and metacognition. Impairments observed following doses of 100-300 mg/70 kg DXM were generally smaller in magnitude than those observed after 0.5 mg/70 kg triazolam. Doses of DXM that impaired performance to the same extent as triazolam were in excess of 10-30 times the therapeutic dose of DXM. CONCLUSION The magnitude of the doses required for these effects and the absence of effects on some tasks within the 100-300 mg/70 kg dose range of DXM, speak to the relatively broad therapeutic window of over-the-counter DXM preparations when used appropriately. However, the administration of supratherapeutic doses of DXM resulted in acute cognitive impairments on all tasks that were examined. These findings are likely relevant to cases of high-dose DXM abuse. PMID:22989498

  19. High-dose MeV electron irradiation of Si-SiO2 structures implanted with high doses Si+

    Science.gov (United States)

    Kaschieva, S.; Angelov, Ch; Dmitriev, S. N.

    2018-03-01

    The influence was studied of 22-MeV electron irradiation on Si-SiO2 structures implanted with high-fluence Si+ ions. Our earlier works demonstrated that Si redistribution is observed in Si+-ion-implanted Si-SiO2 structures (after MeV electron irradiation) only in the case when ion implantation is carried out with a higher fluence (1016 cm-2). We focused our attention on the interaction of high-dose MeV electron irradiation (6.0×1016 cm-2) with n-Si-SiO2 structures implanted with Si+ ions (fluence 5.4×1016 cm-2 of the same order magnitude). The redistribution of both oxygen and silicon atoms in the implanted Si-SiO2 samples after MeV electron irradiation was studied by Rutherford back-scattering (RBS) spectroscopy in combination with a channeling technique (RBS/C). Our results demonstrated that the redistribution of oxygen and silicon atoms in the implanted samples reaches saturation after these high doses of MeV electron irradiation. The transformation of amorphous SiO2 surface into crystalline Si nanostructures (after MeV electron irradiation) was evidenced by atomic force microscopy (AFM). Silicon nanocrystals are formed on the SiO2 surface after MeV electron irradiation. The shape and number of the Si nanocrystals on the SiO2 surface depend on the MeV electron irradiation, while their size increases with the dose. The mean Si nanocrystals height is 16-20 nm after irradiation with MeV electrons at the dose of 6.0×1016 cm-2.

  20. Intensification of antitumor radiation effect by metronidazole and short-term hyperglycemia and dependence of therapeutic effect on schedules of fractionation and value of single dose

    International Nuclear Information System (INIS)

    Venkhvadze, N.G.

    1988-01-01

    Combined application of metronidazole and short-term hyperglycemia under fractionated irradiation of sarcoma-45, 340 in white rats-males is studied. Tumors were γ-irradiated with 60 Co threefold in 48 hours at 15 Gy single dose or irradiated threefold in a week at 20, 25 and 30 Gy doses. Efficiency of experimental therapy is cheked by dynamics of tumor regression, a number of animals with tumors reabsorbed temporarily, a number of animals recovered and time of tumor grouth up to the initial volume. It is established that combined application of metronidazole and short-term hyperglycemia under fractionated irradiation increases essentially the efficiency of radiotherapy carried out by large fractions with great time intervals. 7 refs.; 1 fig.; 2 tabs

  1. Management of acoustic neuromas with fractionated stereotactic radiotherapy (FSRT): Long-term results in 106 patients treated in a single institution

    International Nuclear Information System (INIS)

    Combs, Stephanie E.; Volk, Sigrid; Schulz-Ertner, Daniela; Huber, Peter E.; Thilmann, Christoph; Debus, Juergen

    2005-01-01

    Purpose: To assess the long-term outcome and toxicity of fractionated stereotactic radiotherapy for acoustic neuromas in 106 patients treated in a single institution. Patients and Methods: Between October 1989 and January 2004, fractionated stereotactic radiotherapy (FSRT) was performed in 106 patients with acoustic neuroma (AN). The median total dose applied was 57.6 Gy in median single fractions of 1.8 Gy in five fractions per week. The median irradiated tumor volume was 3.9 mL (range, 2.7-30.7 mL). The median follow-up time was 48.5 months (range, 3-172 months). Results: Fractionated stereotactic radiotherapy was well tolerated in all patients. Actuarial local tumor control rates at 3- and 5- years after FSRT were 94.3% and 93%, respectively. Actuarial useful hearing preservation was 94% at 5 years. The presence of neurofibromatosis (NF-2) significantly adversely influenced hearing preservation in patients that presented with useful hearing at the initiation of RT (p = 0.00062). Actuarial hearing preservation without the diagnosis of NF-2 was 98%. In cases with NF-2, the hearing preservation rate was 64%. Cranial nerve toxicity other than hearing impairment was rare. The rate of radiation induced toxicity to the trigeminal and facial nerve was 3.4% and 2.3%, respectively. Conclusion: Fractionated stereotactic radiotherapy is safe and efficacious for the treatment of AN, with mild toxicity with regard to hearing loss and cranial nerve function. FSRT might be considered as an equieffective treatment modality compared to neurosurgery and therefore represents an interesting alternative therapy for patients with AN

  2. Combination of High-Dose Methylprednisolone and Defibrotide for Veno-Occlusive Disease in Pediatric Hematopoietic Stem Cell Transplant Recipients.

    Science.gov (United States)

    Gloude, Nicholas J; Jodele, Sonata; Teusink-Cross, Ashley; Grimley, Michael; Davies, Stella M; Lane, Adam; Myers, Kasiani C

    2018-01-01

    Veno-occlusive disease (VOD) is a serious complication of hematopoietic stem cell transplant (HSCT), with high mortality in severe cases and until recently very limited therapeutic options consisting largely of supportive care. Defibrotide was recently approved in the United States for the treatment of severe VOD in patients with renal or pulmonary dysfunction after HSCT. Our group previously published on the use of high-dose methylprednisolone (500 mg/m 2 per dose every 12 hours for 6 doses) in patients with VOD, showing good success. A small subset of these individuals were also treated with defibrotide, but additional studies using the combination of high-dose methylprednisolone and defibrotide for the treatment of VOD are lacking. We present a single-institution retrospective chart review of 15 HSCT patients with VOD treated with the combination of high-dose methylprednisolone and defibrotide. VOD developed at a median of 17 days post-HSCT, and combination therapy was initiated within 1 day of VOD diagnosis. Twelve of 15 patients (80%) had multiorgan failure. Our single-center experience using both high-dose methylprednisolone and defibrotide showed a day +100 survival rate of 73% and an overall VOD complete resolution rate of 66.7%, higher than the rates reported in the recent literature using defibrotide alone (40% to 50% day +100 overall survival). These data suggest that the combination of high-dose steroids and defibrotide may be superior to defibrotide alone and warrant further investigation. Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  3. Low- and high-dose laser irradiation effects on cell migration and destruction

    Science.gov (United States)

    Layton, Elivia; Gallagher, Kyra A.; Zukerman, Sara; Stevens, Brianna; Zhou, Feifan; Liu, Hong; Chen, Wei R.

    2018-02-01

    Metastases are the cause of more than 90 percent of cancer-related deaths. Current treatment methods, including chemotherapy, radiation, and surgery, fail to target the metastases effectively. One potential treatment for metastatic cancer is laser immunotherapy (LIT). LIT combines the use of a photothermal laser with an immunoadjuvant, Glycated Chitosan (GC). GC combined with single-walled carbon nanotubes (SWNTs) has proven to be a viable alternative to traditional cancer treatment methods, when under irradiation of laser with appropriate wavelength. In this study, the effects of low dose and high dose laser irradiation on metastatic pancreatic cancer cell migration were observed. It was found that low dose irradiation increased the migration rate, but the high dose irradiation significantly decreased the migration rate of the cancer cells. When using LIT, the goal is to kill tumor cells and to prompt the correct immune response. If the tumor were irradiated with a low dose, it would promote metastasis. If the dose of irradiation were too high, it would destroy the entire tumor and the immune response would not recognize the tumor. Therefore, the laser dose plays an important role in LIT, particularly when using SWNT as light absorbing agent. Our results from this study will delineate the optimal laser irradiation dose for destroying tumor cells and at the same time preserve and release tumor antigens as a precursor of antitumor immune response.

  4. Medical and Psychiatric Effects of Long-Term Dependence on High Dose of tramadol.

    Science.gov (United States)

    El-Hadidy, Mohmed Adel; Helaly, Ahmed Mohamed Nabil

    2015-04-01

    Tramadol dependence has been studied recently after large-scale exposure. Although tramadol dependence has increased rapidly in Egypt since 2004, no studies have evaluated the effect of high dose long-term tramadol dependence. To address the chronic sequel of tramadol dependence over at least 5 years duration with a large dose (more than 675 mg/day, three tablets or more, each tablet of 225 mg). The study was aimed to check the physical and psychiatric status during tramadol dependence and 3 months after complete treatment. The present study was applied on 79 patients with single tramadol-dependence dose of 675 mg or more for 5 years or more. We examined the physical and psychological impact of tramadol abuse before and after 3 months of stoppage of the drug. The blood chemistry was nearly within normal parameters, although slight nonsignificant rise in liver enzymes was reported in some cases. Patients during tramadol dependence period were angry, hostile, and aggressive. On the other hand, after treatment the main problem observed was the significant increase in comorbid anxiety, depressive, and obsessive-compulsive symptoms, but no increase was found in psychotic symptoms. Tramadol-dependence dose was more important than duration of use in psychiatric illness. Tramadol dependence on high dose could be physically safe to some limit, but psychiatrically it has many side effects.

  5. High dose implantations of antimony for buried layer applications

    International Nuclear Information System (INIS)

    Gailliard, J.P.; Dupuy, M.; Garcia, M.; Roussin, J.C.

    1978-01-01

    Electrical and physical properties of high dose implantations of antimony in silicon have been studied for use in buried layer applications. The results have been obtained both on and oriented silicon wafers. Following implantations which lead to amorphization we perform an annealing at 600 0 C for 10 mn in order to recrystallize the layer. The observed electrical properties (μ, R) show that the concentration of electrically active antimony ions is greater than that predicted from the solubility of antimony in silicon. Further annealing (in the range 1050 0 - 1200 0 ) induces: firstly a precipitation of the Sb and secondly a diffusion and dissolution of the precipitates. There is a different evolution of the defects in the and silicon slices. T.E.M. reveals no defects in the wafers after one hour annealing at 1200 0 C, whereas defects and twins remain in wafers. Having obtained the evolution of R with time and temperature it is then determined the implantation and annealing conditions which lead to the low resistivity (R = 10) needed for buried layer applications. Results with very many industrially made devices are discussed

  6. Optimized dose distribution of a high dose rate vaginal cylinder

    International Nuclear Information System (INIS)

    Li Zuofeng; Liu, Chihray; Palta, Jatinder R.

    1998-01-01

    Purpose: To present a comparison of optimized dose distributions for a set of high-dose-rate (HDR) vaginal cylinders calculated by a commercial treatment-planning system with benchmark calculations using Monte-Carlo-calculated dosimetry data. Methods and Materials: Optimized dose distributions using both an isotropic and an anisotropic dose calculation model were obtained for a set of HDR vaginal cylinders. Mathematical optimization techniques available in the computer treatment-planning system were used to calculate dwell times and positions. These dose distributions were compared with benchmark calculations with TG43 formalism and using Monte-Carlo-calculated data. The same dwell times and positions were used for a quantitative comparison of dose calculated with three dose models. Results: The isotropic dose calculation model can result in discrepancies as high as 50%. The anisotropic dose calculation model compared better with benchmark calculations. The differences were more significant at the apex of the vaginal cylinder, which is typically used as the prescription point. Conclusion: Dose calculation models available in a computer treatment-planning system must be evaluated carefully to ensure their correct application. It should also be noted that when optimized dose distribution at a distance from the cylinder surface is calculated using an accurate dose calculation model, the vaginal mucosa dose becomes significantly higher, and therefore should be carefully monitored

  7. Shelf-stable food through high dose irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Placek, V. E-mail: pla@ujv.cz; Svobodova, V.; Bartonicek, B.; Rosmus, J.; Camra, M

    2004-10-01

    Irradiation of food with high doses (radappertization) is a way, how to prepare shelf-stable ready-to-eat food. The radappertization process requires that the food be heated at first to an internal temperature of at least 75 deg. C to inactivate autolytic enzyme, which could cause the spoilage during storage without refrigeration. In order to prevent radiation induced changes in sensory properties (off flavors, odors, undesirable color change, etc.) the food was vacuum packed and irradiated in frozen state at -30 deg. C or less to a minimum dose of 35 kGy. Such products have characteristics of fresh food prepared for eating even if they are stored for long time under tropical conditions. The wholesomeness (safety for consumption) has been confirmed during 40 years of testing. Within the NRI Rez 10 kinds of shelf-stable meat products have been prepared. The meat was cooked, vacuum packed in SiO{sub x}-containing pouch, freezed in liquid nitrogen and irradiated with electron beam accelerator. The microbial, chemical, and organoleptic properties have been tested.

  8. 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.

  9. Characterization of Thymol blue Radiochromic dosimeters for high dose applications

    Directory of Open Access Journals (Sweden)

    Feras M. Aldweri

    2018-03-01

    Full Text Available Thymol blue (TB solutions and Thymol blue Polyvinyl Alcohol (TB-PVA films have been introduced as Radiochromic dosimeter for high dose applications. The dosimeters were irradiated with gamma ray (60Co source from 5 to 30 kGy for film, and from 0.150 kGy to 4 kGy for solution. The optical density of unirradiated and irradiated TB solution as well as TB-PVA film dosimeters were studied in terms of absorbance at 434 nm using UV/VIS spectrophotometer. The effects of scan temperature, light pre-gamma irradiation, dose rate, relative humidity and stability of the absorbance of solutions and films after irradiation were investigated. We found the dose sensitivity of TB solution and TB-PVA film dosimeters increases significantly with increases of the absorbed dose as well as with the increases of TB dye concentrations. The useful dose range of developed TB solutions and TB-PVA films dosimeters is in the range 0.125–1 kGy and of 5–20 kGy, respectively. Keywords: Dose sensitivity, Radio-chromic dosimeter, Thymol blue, Absorbance, Concentrations

  10. Shelf-stable food through high dose irradiation

    International Nuclear Information System (INIS)

    Placek, V.; Svobodova, V.; Bartonicek, B.; Rosmus, J.; Camra, M.

    2004-01-01

    Irradiation of food with high doses (radappertization) is a way, how to prepare shelf-stable ready-to-eat food. The radappertization process requires that the food be heated at first to an internal temperature of at least 75 deg. C to inactivate autolytic enzyme, which could cause the spoilage during storage without refrigeration. In order to prevent radiation induced changes in sensory properties (off flavors, odors, undesirable color change, etc.) the food was vacuum packed and irradiated in frozen state at -30 deg. C or less to a minimum dose of 35 kGy. Such products have characteristics of fresh food prepared for eating even if they are stored for long time under tropical conditions. The wholesomeness (safety for consumption) has been confirmed during 40 years of testing. Within the NRI Rez 10 kinds of shelf-stable meat products have been prepared. The meat was cooked, vacuum packed in SiO x -containing pouch, freezed in liquid nitrogen and irradiated with electron beam accelerator. The microbial, chemical, and organoleptic properties have been tested

  11. Ion exchange resins as high-dose radiation dosimeters

    International Nuclear Information System (INIS)

    Alian, A.; Dessouki, A.; El-Assay, N.B.

    1984-01-01

    This paper reports on the possibility of using various types of ion exchange resins as high-dose radiation dosimeters, by analysis of the decrease in exchange capacity with absorbed dose. The resins studied are Sojuzchim-export-Moscow Cation Exchanger KU-2 and Anion Exchanger AV-17 and Merck Cation Exchanger I, and Merck Anion Exchangers II and III. Over the dose range 1 to 100 kGy, the systems show linearity between log absorbed dose and decrease in resin ion exchange capacity. The slope of this response function differs for the different resins, depending on their ionic form and degree of cross-linking. The radiation sensitivity increases in the order KU-2; Exchanger I; AV-17; Exchanger II; Exchanger III. Merck resins with moisture content of 21% showed considerably higher radiation sensitivity than those with 2 to 3% moisture content. The mechanism of radiation-induced denaturing of the ion exchanger resins involves cleavage and decomposition of functional substituents, with crosslinking playing a stabilizing role, with water and its radiolytic products serving to inhibit radical recombination and interfering with the protection cage effect of crosslinking. (author)

  12. High dose rate brachytherapy for the palliation of malignant dysphagia

    International Nuclear Information System (INIS)

    Homs, Marjolein Y.V.; Eijkenboom, Wilhelmina M.H.; Coen, Veronique L.M.A.; Haringsma, Jelle; Blankenstein, Mark van; Kuipers, Ernst J.; Siersema, Peter D.

    2003-01-01

    Background and purpose: High dose rate (HDR) brachytherapy is a commonly used palliative treatment for esophageal carcinoma. We evaluated the outcome of HDR brachytherapy in patients with malignant dysphagia. Material and methods: A retrospective analysis over a 10-year period was performed of 149 patients treated with HDR brachytherapy, administered in one or two sessions, at a median dose of 15 Gy. Patients were evaluated for functional outcome, complications, recurrent dysphagia, and survival. Results: At 6 weeks after HDR brachytherapy, dysphagia scores had improved from a median of 3 to 2 (n=104; P<0.001), however, dysphagia had not improved in 51 (49%) patients. Procedure-related complications occurred in seven (5%) patients. Late complications, including fistula formation or bleeding, occurred in 11 (7%) patients. Twelve (8%) patients experienced minor retrosternal pain. Median survival of the patients was 160 days with a 1-year survival rate of 15%. Procedure-related mortality was 2%. At follow-up, 55 (37%) patients experienced recurrent dysphagia. In 34 (23%) patients a metal stent was placed to relieve persistent or recurrent dysphagia. Conclusion: HDR brachytherapy is a moderately effective treatment for the palliation of malignant dysphagia. The incidence of early major complications is low, however, persistent and recurrent dysphagia occur frequently, and require often additional treatment

  13. 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.

  14. Dimethyl sulfoxyde diethyl fumarate solution for high dose dosimetry

    International Nuclear Information System (INIS)

    Al-Kassiri, H.; Kattan, M.; Daher, Y.

    2007-06-01

    Dosimetric characterization of diethyl fumarate DEF in dimethyl sulfoxyde DMSO solution has been studied spectrophotometrically for possible application at high dose radiation dosimetry in the range (0-225 kGy). The absorption spectra of irradiated solution showed broad absorption bands between (325-400 nm) with a shoulder at 332 nm. The absorption increases as the dose is increased. Absorbance at 332 nm were measured and plotted against absorbed dose. Linear relationship and good response were found between absorbed dose and absorbance of 20% DEF concentration in the range (0-225 kGy) at the wave length, and linearity up to 250 kGy of absorbance at 332 nm .Good dose rate independence was observed in the range (14-33 kGy/h). The effect of post irradiation storage in darkness and indirect daylight conditions were not found to influence the absorption up to 700 h after irradiation. The effect of irradiation temperature within the range (0 to 60 centigrade degree) on the dosimetry performance was discussed.(author)

  15. Radiation Parameters of High Dose Rate Iridium -192 Sources

    Science.gov (United States)

    Podgorsak, Matthew B.

    A lack of physical data for high dose rate (HDR) Ir-192 sources has necessitated the use of basic radiation parameters measured with low dose rate (LDR) Ir-192 seeds and ribbons in HDR dosimetry calculations. A rigorous examination of the radiation parameters of several HDR Ir-192 sources has shown that this extension of physical data from LDR to HDR Ir-192 may be inaccurate. Uncertainty in any of the basic radiation parameters used in dosimetry calculations compromises the accuracy of the calculated dose distribution and the subsequent dose delivery. Dose errors of up to 0.3%, 6%, and 2% can result from the use of currently accepted values for the half-life, exposure rate constant, and dose buildup effect, respectively. Since an accuracy of 5% in the delivered dose is essential to prevent severe complications or tumor regrowth, the use of basic physical constants with uncertainties approaching 6% is unacceptable. A systematic evaluation of the pertinent radiation parameters contributes to a reduction in the overall uncertainty in HDR Ir-192 dose delivery. Moreover, the results of the studies described in this thesis contribute significantly to the establishment of standardized numerical values to be used in HDR Ir-192 dosimetry calculations.

  16. 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.

  17. Tungsten and carbon surface change under high dose plasma exposure

    International Nuclear Information System (INIS)

    Martynenko, Y.V.; Khripunov, B.I.; Petrov, V.B.

    2009-01-01

    Study of surface composition dynamics has been made on the LENTA linear plasma simulator. Experiments have been made on tungsten and carbon materials subjected to steady-state plasma exposure. The achieved ion doses on the surface were 10 21 ion cm -2 . WL 10 tungsten containing 1% of La2O3 oxide and titanium-doped graphite RG-T were studied. The following experimental conditions were varied in these experiments: energy of ions, surface temperature, working gas. Irradiations of tungsten WL 10 were executed in deuterium plasma at low ion energies (about 20 eV) and at 200 eV for temperatures below 340 K. Graphite RG-T was exposed at 1300 K. Elevated surface temperature (about 1050K) was also characteristic of experiments on tungsten sample under nitrogen plasma impact (simulated inter-ELMs condition). Surface microstructure modification has been observed and surface composition changes were found on the materials showing influence of high dose plasma irradiations on element redistribution in the near surface layers. (author)

  18. High dose progesterone effects the growth of early chick embryo

    International Nuclear Information System (INIS)

    Iqbal, I.; Qamar, K.

    2014-01-01

    Objective: To find out the effect of high dose progesterone on the development of early chick embryo. Study Design: Lab based randomized controlled trial. Place and Duration of study: This study was carried out in Army Medical College and Post Graduate Institute of Poultry Sciences, Rawalpindi from June 2010 - December 2010. Material and Methods: Forty five specific pathogen free, fertile, eggs of Fyoumi species of chick were selected at zero hour of incubation. They were incubated at 37.5oC and 75% relative humidity for 26 hrs until the embryos reached stage 8 of the development. Then on stage 8 the eggs were divided into three groups consisting of 15 eggs per group. The first group (GI) was incubated without any operation. The second (G2) and third groups (G3) were injected with two and twenty times more than physiologic does of progesterone respectively. After 48 hours of incvbation, all embryos were examined for their development under light microscopy. Results: All the embryos of G1 and G2 showed normal development according to their stage of development, while 4 out of 11 embryos of G3 were under developed and their survival rate was also less. Conclusion: Exogenous progesterone at levels twenty times above its physiologic range effects the development of chick embryos. Further studies are needed to explain the mechanisms of this effect. (author)

  19. Calibration of high-dose radiation facilities (Handbook)

    International Nuclear Information System (INIS)

    Gupta, B.L.; Bhat, R.M.

    1986-01-01

    In India at present several high intensity radiation sources are used. There are 135 teletheraphy machines and 65 high intensity cobalt-60 sources in the form of gamma chambers (2.5 Ci) and PANBIT (50 Ci). Several food irradiation facilities and a medical sterilization plant ISOMED are also in operation. The application of these high intensity sources involve a wide variation of dose from 10 Gy to 100 kGy. Accurate and reproducible radiation dosimetry is essential in the use of these sources. This handbook is especially compiled for calibration of high-dose radiation facilities. The first few chapters discuss such topics as interaction of radiation with matter, radiation chemistry, radiation processing, commonly used high intensity radiation sources and their special features, radiation units and dosimetry principles. In the chapters which follow, chemical dosimeters are discussed in detail. This discussion covers Fricke dosimeter, FBX dosimeter, ceric sulphate dosimeter, free radical dosimetry, coloured indicators for irrdiation verification. A final chapter is devoted to practical hints to be followed in calibration work. (author)

  20. High-dose processing and application to Korean space foods

    International Nuclear Information System (INIS)

    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

    2009-01-01

    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 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.

  1. Radiation-induced transformation of SV40-immortalized human thyroid epithelial cells by single and fractionated exposure to γ-irradiation in vitro

    International Nuclear Information System (INIS)

    Riches, A.C.; Herceg, Z.; Bryant, P.E.; Wynford-Thomas, D.

    1994-01-01

    Radiation-induced transformation of a human thyroid epithelial cell line (HTori-3) has been investigated following exposure to single and fractionated doses of γ-irradiation. The human epithelial cells were irradiated in vitro and following passaging, transplanted to the athymic nude mouse. Following a single exposure to γ-irradiation in the range 0.5-4Gy, 22 tumours were observed in 45 recipients and following three equal fractions in the range 0.5-4Gy per fraction, 18 tumours were observed in 31 recipients. Tumours were undifferentiated carcinomas and were observed from 7 to 20 weeks after transplantation. They occurred after similar radiation doses to those received by the children in the Belarus region of Ukraine, who developed thyroid tumours. The number of tumours observed, in each group receiving cells irradiated with a single dose of γ-irradiation in the range 0.5-4 Gy, was similar. Cell lines were established from some tumours and the tumorigenicity confirmed by retransplantation. These tumour cell lines were more radiosensitive than the human thyroid epithelial cell line they were derived from. This indicates that transformed cells were not being selected from a subpopulation within the parent cell line but that radiation-induced transformants were being induced de novo. The human origin of the tumours was established by karyotyping, immunocytochemical demonstration of human epithelial cytokeratins and p53 analysis. DNA fingerprinting confirmed that the tumours were derived from the original cell line. (author)

  2. On the use of volumetric-modulated arc therapy for single-fraction thoracic vertebral metastases stereotactic body radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Pokhrel, Damodar, E-mail: damodar.pokhrel@uky.edu; Sood, Sumit; McClinton, Christopher; Shen, Xinglei; Badkul, Rajeev; Jiang, Hongyu; Mallory, Matthew; Mitchell, Mellissa; Wang, Fen; Lominska, Christopher

    2017-04-01

    To retrospectively evaluate quality, efficiency, and delivery accuracy of volumetric-modulated arc therapy (VMAT) plans for single-fraction treatment of thoracic vertebral metastases using image-guided stereotactic body radiosurgery (SBRS) after RTOG 0631 dosimetric compliance criteria. After obtaining credentialing for MD Anderson spine phantom irradiation validation, 10 previously treated patients with thoracic vertebral metastases with noncoplanar hybrid arcs using 1 to 2 3D-conformal partial arcs plus 7 to 9 intensity-modulated radiation therapy beams were retrospectively re-optimized with VMAT using 3 full coplanar arcs. Tumors were located between T2 and T12. Contrast-enhanced T1/T2-weighted magnetic resonance images were coregistered with planning computed tomography and planning target volumes (PTV) were between 14.4 and 230.1 cc (median = 38.0 cc). Prescription dose was 16 Gy in 1 fraction with 6 MV beams at Novalis-TX linear accelerator consisting of micro multileaf collimators. Each plan was assessed for target coverage using conformality index, the conformation number, the ratio of the volume receiving 50% of the prescription dose over PTV, R50%, homogeneity index (HI), and PTV-1600 coverage per RTOG 0631 requirements. Organs-at-risk doses were evaluated for maximum doses to spinal cord (D{sub 0.03} {sub cc}, D{sub 0.35} {sub cc}), partial spinal cord (D{sub 10%}), esophagus (D{sub 0.03} {sub cc} and D{sub 5} {sub cc}), heart (D{sub 0.03} {sub cc} and D{sub 15} {sub cc}), and lung (V{sub 5}, V{sub 10}, and maximum dose to 1000 cc of lung). Dose delivery efficiency and accuracy of each VMAT-SBRS plan were assessed using quality assurance (QA) plan on MapCHECK device. Total beam-on time was recorded during QA procedure, and a clinical gamma index (2%/2 mm and 3%/3 mm) was used to compare agreement between planned and measured doses. All 10 VMAT-SBRS plans met RTOG 0631 dosimetric requirements for PTV coverage. The plans demonstrated highly conformal and

  3. Postoperative vaginal irradiation by a high dose-rate afterloading technique in endometrial carcinoma stage I

    International Nuclear Information System (INIS)

    Sorbe, B.; Smeds, A.C.

    1989-01-01

    A high dose-rate (cobalt-60) afterloading technique was used for postoperative vaginal irradiation in a series of 404 women with endometrial carcinoma stage I. The total recurrence rate was 3.7% with 0.7% vaginal lesions. The crude 5-year survival rate for the complete series was 91.8% compared to 13.3% for those with recurrences. Depth of myometrical infiltration (>1/3 of the uterine wall) and nuclear grade were the most important prognostic factors. Clinically significant late radiation reactions (bladder and/or rectum) were recorded in 6.9%. The absorbed dose per fraction and the size of the treatment volume were significantly related to the occurrence of both early and late radiation reactions. Vaginal shortening was closely related to the dose per fraction, length of the referce isodose and the applicator diameter. The shape of the vaginal applicator versus the isodose contours and the importance of the source train geometry and relative activity for absorbed dose inhomogeneitis within the treatment volume are discussed. Cumulative radiation effect (CRE) and linear-quadratic (LQ) calculations have been performed and related to tissue reactions within the target volume and in the risk organs. An alpha-beta quotient of 8.8 Gy for vaginal shrinkage effect and 2.0 Gy for late rectal complications are suggested on the basis of calculations using a maximum likelihood method for quantal radiation data. (orig.)

  4. Postoperative vaginal irradiation with high dose rate afterloading technique in endometrial carcinoma stage I

    International Nuclear Information System (INIS)

    Sorbe, B.G.; Smeds, A.C.

    1990-01-01

    A high dose rate ( 60 Co) afterloading technique was used for postoperative prophylactic vaginal irradiation in a series of 404 women with endometrial carcinoma Stage I. The total recurrence rate was 3.7% with 0.7% vaginal deposits. The crude 5-year survival rate for the complete series was 91.8% compared to 13.3% for those with recurrences. Depth of myometrial infiltration (greater than 1/3 of the uterine wall) and nuclear grade were the most important prognostic factors. Clinically significant late radiation reactions (bladder and/or rectum) were recorded in 6.9%. Dose per fraction and the size of the target volume were highly significantly related to the occurrence of both early and late radiation reactions. Vaginal shortening is closely related to the dose per fraction, length of the reference isodose, and the applicator diameter. The shape of the vaginal applicator versus the isodoses and the importance of the source train geometry and relative activity for dose gradient inhomogeneities within the target volume are discussed. Cumulative radiation effect (CRE) and linear-quadratic (LQ) calculations have been performed and related to tissue reactions within the target volume and in the risk organs. An alpha-beta quotient of 8.8 for vaginal shrinkage effect and 2.0 for late rectal complications are suggested on the basis of calculations using a maximum likelihood method for quantal radiation data

  5. Adjuvant high-dose-rate brachytherapy after external beam radiotherapy in nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Oezyar, Enis; Yildz, Ferah; Akyol, Fadil H.; Atahan, I. Lale

    2002-01-01

    Purpose: To compare the local control and survival rates obtained with either external beam radiation therapy (ERT) and adjuvant high-dose-rate (HDR) brachytherapy (BRT) or ERT alone in patients with nasopharyngeal cancer. Methods and Materials: Between December 1993 and December 1999, 144 patients (106 male, 38 female) with the diagnosis of nasopharyngeal cancer were treated with either ERT and adjuvant HDR BRT (Group A) or ERT alone (Group B) at our department. BRT was not applied in 38 patients for the following reasons: (1) Unit was unavailable (n=13), (2) Patient was younger than 18 years (n=17), (3) Patient received accelerated hyperfractionated ERT (n=6), and (4) Patient refused BRT (n=2). The median age for whole group was 43 (range: 9-82 years). According to the AJCC-1997 staging system, there were 11 (7.6%), 35 (24.3%), 38 (26.4%), and 60 (41.7%) patients in Stage I, II, III, and IV, respectively. There were 57 (39.6%) patients with T1, 41 (28.5%) with T2, 20 (13.9%) with T3, and 26 (18.1%) with T4 tumors. Histopathologic diagnosis was WHO 2-3 in 137 (95.2%) patients. ERT doses ranged between 58.8 and 74 Gy (median: 66 Gy). There were significantly more patients with young age, N2 status, and Stage III disease in Group B and with Stage II disease in Group A. Significantly more patients received chemotherapy in Group B. BRT with an HDR 192 Ir microSelectron afterloading unit was delivered in 106 patients at the conclusion of ERT using a single-channel nasal applicator. Dose was prescribed at 1 cm from the source, and total dose of 12 Gy in 3 fractions on 3 consecutive days was given immediately after ERT. Besides radiotherapy, 82 (56.9%) patients received cisplatin-based chemotherapy, as well. Follow-up time ranged between 12 and 80 months (median: 32 months). Results: The two groups were comparable in terms of local recurrence, locoregional failure, regional failure, and rate of distant metastasis. Local failure was observed in 11 (10.3%) out of 106

  6. 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

  7. High-Dose-Rate Endobronchial Brachytherapy for Recurrent Airway Obstruction From Hyperplastic Granulation Tissue

    International Nuclear Information System (INIS)

    Tendulkar, Rahul D.; Fleming, Peter A.; Reddy, Chandana A.; Gildea, Thomas R.; Machuzak, Michael; Mehta, Atul C.

    2008-01-01

    Purpose: Benign endobronchial granulation tissue causes airway obstruction in up to 20% of patients after lung transplantation or stent placement. High-dose-rate endobronchial brachytherapy (HDR-EB) has been successful in some cases refractory to standard bronchoscopic interventions. Methods and Materials: Between September 2004 and May 2005, 8 patients with refractory benign airway obstruction were treated with HDR-EB, using one to two fractions of Ir-192 prescribed to 7.1 Gy at a radius of 1 cm. Charts were retrospectively reviewed to evaluate subjective clinical response, forced expiratory volume in 1 second (FEV 1 ), and frequency of therapeutic bronchoscopies over 6-month periods before and after HDR-EB. Results: The median follow-up was 14.6 months, and median survival was 10.5 months. The mean number of bronchoscopic interventions improved from 3.1 procedures in the 6-month pretreatment period to 1.8 after HDR-EB. Mean FEV 1 improved from 36% predicted to 46% predicted. Six patients had a good-to-excellent subjective early response, but only one maintained this response beyond 6 months, and this was the only patient treated with HDR-EB within 24 h from the most recent bronchoscopic intervention. Five patients have expired from causes related to their chronic pulmonary disease, including one from hemoptysis resulting from a bronchoarterial fistula. Conclusion: High-dose-rate-EB may be an effective treatment for select patients with refractory hyperplastic granulation tissue causing recurrent airway stenosis. Performing HDR-EB within 24-48 h after excision of obstructive granulation tissue could further improve outcomes. Careful patient selection is important to maximize therapeutic benefit and minimize toxicity. The optimal patient population, dose, and timing of HDR-EB should be investigated prospectively

  8. High-dose simultaneously integrated breast boost using intensity-modulated radiotherapy and inverse optimization

    International Nuclear Information System (INIS)

    Hurkmans, Coen W.; Meijer, Gert J.; Vliet-Vroegindeweij, Corine van; Sangen, Maurice J. van der; Cassee, Jorien

    2006-01-01

    Purpose: Recently a Phase III randomized trial has started comparing a boost of 16 Gy as part of whole-breast irradiation to a high boost of 26 Gy in young women. Our main aim was to develop an efficient simultaneously integrated boost (SIB) technique for the high-dose arm of the trial. Methods and Materials: Treatment planning was performed for 5 left-sided and 5 right-sided tumors. A tangential field intensity-modulated radiotherapy technique added to a sequentially planned 3-field boost (SEQ) was compared with a simultaneously planned technique (SIB) using inverse optimization. Normalized total dose (NTD)-corrected dose volume histogram parameters were calculated and compared. Results: The intended NTD was produced by 31 fractions of 1.66 Gy to the whole breast and 2.38 Gy to the boost volume. The average volume of the PTV-breast and PTV-boost receiving more than 95% of the prescribed dose was 97% or more for both techniques. Also, the mean lung dose and mean heart dose did not differ much between the techniques, with on average 3.5 Gy and 2.6 Gy for the SEQ and 3.8 Gy and 2.6 Gy for the SIB, respectively. However, the SIB resulted in a significantly more conformal irradiation of the PTV-boost. The volume of the PTV-breast, excluding the PTV-boost, receiving a dose higher than 95% of the boost dose could be reduced considerably using the SIB as compared with the SEQ from 129 cc (range, 48-262 cc) to 58 cc (range, 30-102 cc). Conclusions: A high-dose simultaneously integrated breast boost technique has been developed. The unwanted excessive dose to the breast was significantly reduced

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

    International Nuclear Information System (INIS)

    Chatzikonstantinou, Georgios; Zamboglou, Nikolaos; Roedel, Claus; Tselis, Nikolaos; Zoga, Eleni; Strouthos, Iosif; Butt, Saeed Ahmed

    2017-01-01

    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.) [de

  10. Better compliance with hypofractionation vs. conventional fractionation in adjuvant breast cancer radiotherapy. Results of a single, institutional, retrospective study

    Energy Technology Data Exchange (ETDEWEB)

    Rudat, Volker; Nour, Alaa; Hammoud, Mohamed; Abou Ghaida, Salam [Saad Specialist Hospital, Department of Radiation Oncology, Al Khobar (Saudi Arabia)

    2017-05-15

    The aim of the study was to identify factors significantly associated with the occurrence of unintended treatment interruptions in adjuvant breast cancer radiotherapy. Patients treated with postoperative radiotherapy of the breast or chest wall between March 2014 and August 2016 were evaluated. The radiotherapy regimens and techniques applied were either conventional fractionation (CF; 28 daily fractions of 1.8 Gy or 25 fractions of 2.0 Gy) or hypofractionation (HF; 15 daily fractions of 2.67 Gy) with inverse planned intensity-modulated radiotherapy (IMRT) or three-dimensional planned conformal radiotherapy (3DCRT). Logistic regression analysis was used to identify factors associated with noncompliance. Noncompliance was defined as the missing of at least one scheduled radiotherapy fraction. In all, 19 of 140 (13.6%) patients treated with HF and 39 of 146 (26.7%) treated with CF experienced treatment interruptions. Of 23 factors tested, the fractionation regimen emerged as the only independent significant prognostic factor for noncompliance on multivariate analysis (CF; p = 0.007; odds ratio, 2.3; 95% confidence interval, 1.3-4.2). No statistically significant differences concerning the reasons for treatment interruptions could be detected between patients treated with CF or HF. HF is significantly associated with a better patient compliance with the prescribed radiotherapy schedule compared with CF. The data suggest that this finding is basically related to the shorter overall treatment time of HF. (orig.) [German] Ziel der Untersuchung war es, Faktoren zu identifizieren, die mit ungeplanten Behandlungsunterbrechungen bei der adjuvanten Strahlentherapie des Mammakarzinoms assoziiert sind. Es wurden Patienten untersucht, die eine adjuvante Strahlentherapie der Mamma oder Brustwand zwischen Maerz 2014 und August 2016 erhielten. Zur Anwendung kamen als Fraktionierungsprotokoll und strahlentherapeutische Technik eine konventionell fraktionierte (CF; 28 Fraktionen mit

  11. Investigation of polymer composite for high dose dosimetry

    International Nuclear Information System (INIS)

    Pereira, E.L.M.; Batista, A.S.M.; Ribeiro, F.A.S.; Santos, A.P.; Faria, L.O.; Oliveira, A.H.

    2017-01-01

    Introduction: This paper presents the efficacy evaluation of PVDF and nanocomposites of the PVDF films for high gamma dosimetry. Our scope in this first part of our studies is the selection of the most promising film for future dosimetry trials, where the proportionality of response of the selected material will be investigated over a large range of doses and dose rates. Methods: Was prepared nanocomposites made by mixing Poly(vinylidene fluoride) (PVDF), zirconium oxide (ZrO 2 ) and multi-walled carbon nanotubes (MWCNTs) aiming to find dosimetric properties for applications in high dose dosimetry. The samples were irradiated with a Co-60 source at constant dose rate (16.7 kGy/h), with doses ranging from 100 to 2750 kGy. The UV-Vis and FTIR spectrophotometry have been used to monitor the appearing of C=C conjugated bonds and radio-oxidation of carbon (C=O). Results: FTIR spectrometry has that the absorbance intensities at 1715 cm -1 and 1730 cm -1 can be used for high dosimetry purposes for gamma doses ranging from 400 to 2750 kGy. In this range, it is possible to observe a linear relationship between Abs & Dose. Fading of signal was evaluated for one month and reproducibility in 2000 kGy dose. Conclusion: FTIR spectroscopic data revealed two optical absorption bands at 1715 cm -1 and 1730 cm -1 whose intensities are unambiguously related to gamma delivered dose ranging from 400 kGy to 2750 kGy. (author)

  12. Investigation of polymer composite for high dose dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, E.L.M.; Batista, A.S.M., E-mail: adriananuclear@yahoo.com.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil); Ribeiro, F.A.S.; Santos, A.P.; Faria, L.O.; Oliveira, A.H. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-07-01

    Introduction: This paper presents the efficacy evaluation of PVDF and nanocomposites of the PVDF films for high gamma dosimetry. Our scope in this first part of our studies is the selection of the most promising film for future dosimetry trials, where the proportionality of response of the selected material will be investigated over a large range of doses and dose rates. Methods: Was prepared nanocomposites made by mixing Poly(vinylidene fluoride) (PVDF), zirconium oxide (ZrO{sub 2}) and multi-walled carbon nanotubes (MWCNTs) aiming to find dosimetric properties for applications in high dose dosimetry. The samples were irradiated with a Co-60 source at constant dose rate (16.7 kGy/h), with doses ranging from 100 to 2750 kGy. The UV-Vis and FTIR spectrophotometry have been used to monitor the appearing of C=C conjugated bonds and radio-oxidation of carbon (C=O). Results: FTIR spectrometry has that the absorbance intensities at 1715 cm{sup -1} and 1730 cm{sup -1} can be used for high dosimetry purposes for gamma doses ranging from 400 to 2750 kGy. In this range, it is possible to observe a linear relationship between Abs & Dose. Fading of signal was evaluated for one month and reproducibility in 2000 kGy dose. Conclusion: FTIR spectroscopic data revealed two optical absorption bands at 1715 cm{sup -1} and 1730 cm{sup -1} whose intensities are unambiguously related to gamma delivered dose ranging from 400 kGy to 2750 kGy. (author)

  13. 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.

  14. "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.

  15. Experimentally induced, synergistic late effects of a single dose of radiation and aging: significance in LKS fraction as compared with mature blood cells.

    Science.gov (United States)

    Hirabayashi, Yoko; Tsuboi, Isao; Nakachi, Kei; Kusunoki, Yoichiro; Inoue, Tohru

    2015-03-01

    The number of murine mature blood cells recovered within 6 weeks after 2-Gy whole-body irradiation at 6 weeks of age, whereas in the case of the undifferentiated hematopoietic stem/progenitor cell (HSC/HPC) compartment [cells in the lineage-negative, c-kit-positive and stem-cell-antigen-1-positive (LKS) fraction], the numerical differences between mice with and without irradiation remained more than a year, but conclusively the cells showed numerical recovery. When mice were exposed to radiation at 6 months of age, acute damages of mature blood cells were rather milder probably because of their maturation with age; but again, cells in the LKS fraction were specifically damaged, and their numerical recovery was significantly delayed probably as a result of LKS-specific cellular damages. Interestingly, in contrast to the recovery of the number of cells in the LKS fraction, their quality was not recovered, which was quantitatively assessed on the basis of oxidative-stress-related fluorescence intensity. To investigate why the recovery in the number of cells in the LKS fraction was delayed, expression levels of genes related to cellular proliferation and apoptosis of cells in the bone marrow and LKS fraction were analyzed by real-time polymerase chain reaction (RT-PCR). In the case of 21-month-old mice after radiation exposure, Ccnd1, PiK3r1 and Fyn were overexpressed solely in cells in the LKS fraction. Because Ccnd1and PiK3r1 upregulated by aging were further upregulated by radiation, single-dose radiation seemed to induce the acceleration of aging, which is related to the essential biological responses during aging based on a lifetime-dependent relationship between a living creature and xenobiotic materials. Copyright © 2014 John Wiley & Sons, Ltd.

  16. High dose rate versus low dose rate interstitial radiotherapy for carcinoma of the floor of mouth

    International Nuclear Information System (INIS)

    Inoue, Takehiro; Inoue, Toshihiko; Yamazaki, Hideya; Koizumi, Masahiko; Kagawa, Kazufumi; Yoshida, Ken; Shiomi, Hiroya; Imai, Atsushi; Shimizutani, Kimishige; Tanaka, Eichii; Nose, Takayuki; Teshima, Teruki; Furukawa, Souhei; Fuchihata, Hajime

    1998-01-01

    Purpose: Patients with cancer of the floor of mouth are treated with radiation because of functional and cosmetic reasons. We evaluate the treatment results of high dose rate (HDR) and low dose rate (LDR) interstitial radiation for cancer of the floor of mouth. Methods and Materials: From January 1980 through March 1996, 41 patients with cancer of the floor of mouth were treated with LDR interstitial radiation using 198 Au grains, and from April 1992 through March 1996 16 patients with HDR interstitial radiation. There were 26 T1 tumors, 30 T2 tumors, and 1 T3 tumor. For 21 patients treated with interstitial radiation alone, a total radiation dose of interstitial therapy was 60 Gy/10 fractions/6-7 days in HDR and 85 Gy within 1 week in LDR. For 36 patients treated with a combination therapy, a total dose of 30 to 40 Gy of external radiation and a total dose of 48 Gy/8 fractions/5-6 days in HDR or 65 Gy within 1 week in LDR were delivered. Results: Two- and 5-year local control rates of patients treated with HDR interstitial radiation were 94% and 94%, and those with LDR were 75% and 69%, respectively. Local control rate of patients treated with HDR brachytherapy was slightly higher than that with 198 Au grains (p = 0.113). For late complication, bone exposure or ulcer occurred in 6 of 16 (38%) patients treated with HDR and 13 of 41 (32%) patients treated with LDR. Conclusion: HDR fractionated interstitial brachytherapy can be an alternative to LDR brachytherapy for cancer of the floor of mouth and eliminate radiation exposure for the medical staff

  17. Zinc fractionation in contaminated soils by sequential and single extractions: influence of soil properties and zinc content.

    Science.gov (United States)

    Voegelin, Andreas; Tokpa, Gerome; Jacquat, Olivier; Barmettler, Kurt; Kretzschmar, Ruben

    2008-01-01

    We studied the fractionation of zinc (Zn) in 49 contaminated soils as influenced by Zn content and soil properties using a seven-step sequential extraction procedure (F1: NH4NO3; F2: NH4-acetate, pH 6; F3: NH3OHCl, pH 6; F4: NH4-EDTA, pH 4.6; F5: NH4-oxalate, pH 3; F6: NH4-oxalate/ascorbic acid, pH 3; F7: residual). The soils had developed from different geologic materials and covered a wide range in soil pH (4.0-7.3), organic C content (9.3-102 g kg(-1)), and clay content (38-451 g kg(-1)). Input of aqueous Zn with runoff water from electricity towers during 26 to 74 yr resulted in total soil Zn contents of 3.8 to 460 mmol kg(-1). In acidic soils (n = 24; pH soils (n = 25; pH > or =6.0), most Zn was extracted in the mobilizable fraction (F2) and the intermediate fractions (F4 and F5). The extractability of Zn increased with increasing Zn contamination of the soils. The sum of mobile (F1) and mobilizable (F2) Zn was independent of soil pH, the ratio of Zn in F1 over F1+F2 plotted against soil pH, exhibited the typical shape of a pH sorption edge and markedly increased from pH 6 to pH 5, reflecting the increasing lability of mobilizable Zn with decreasing soil pH. In conclusion, the extractability of Zn from soils contaminated with aqueous Zn after decades of aging under field conditions systematically varied with soil pH and Zn content. The same trends are expected to apply to aqueous Zn released from decomposing Zn-bearing contaminants, such as sewage sludge or smelter slag. The systematic trends in Zn fractionation with varying soil pH and Zn content indicate the paramount effect of these two factors on molecular scale Zn speciation. Further research is required to characterize the link between the fractionation and speciation of Zn and to determine how Zn loading and soil physicochemical properties affect Zn speciation in soils.

  18. HIGH-DOSE RATE BRACHYTHERAPY IN CARCINOMA CERVIX STAGE IIIB

    Directory of Open Access Journals (Sweden)

    Sathya Maruthavanan

    2016-07-01

    Full Text Available INTRODUCTION Radiotherapy is the standard treatment in locally advanced (IIB-IVA and early inoperable cases. The current standard of practice with curable intent is concurrent chemoradiation in which intracavitary brachytherapy is an integral component of radiotherapy. This study aims at assessing the efficacy of HDR ICBT (High-dose rate intracavitary brachytherapy in terms local response, normal tissue reactions, and feasibility. METHODS AND MATERIALS A total of 20 patients of stage IIIB cancer of the uterine cervix were enrolled in the study and were planned to receive concurrent chemotherapy weekly along with EBRT (external beam radiotherapy to a dose of 50 Gy/25 Fr. Suitability for ICBT was assessed at 40 Gy/20 Fr. 6/20 patients were suitable at 40 Gy and received HDR ICBT with a dose of 5.5 Gy to point A in 4 sessions (5.5 Gy/4 Fr. The remaining 14/20 patients completed 50 Gy and received HDR ICBT with a dose of 6 Gy to point A in 3 sessions (6 Gy/3 Fr. RESULTS A total of 66 intracavitary applications were done and only one application required dose modification due to high bladder dose, the pelvic control rate was 85% (17/20. 10% (2/20 had stable disease and 5% (1/20 had progressive disease at one year of follow up. When toxicity was considered only 15% developed grade I and grade II rectal complications. Patient compliance and acceptability was 100%. Patients were very comfortable with the short treatment time as compared with patients on LDR ICBT (low-dose rate intracavitary brachytherapy treatment interviewed during the same period. CONCLUSION This study proves that HDR brachytherapy is efficacious and feasible in carcinoma of cervix stage IIIB. It also proves that good dose distribution can be achieved with HDR intracavitary facility by the use of dose optimization. The short treatment time in HDR ICBT makes it possible to maintain this optimised dose distribution throughout the treatment providing a gain in the therapeutic ratio and

  19. Early quality of life outcomes in patients with prostate cancer managed by high-dose-rate brachytherapy as monotherapy

    International Nuclear Information System (INIS)

    Komiya, Akira; Fujiuchi, Yasuyoshi; Ito, Takatoshi

    2013-01-01

    The purpose of this study was to evaluate the early quality of life outcomes in prostate cancer patients managed by high-dose-rate brachytherapy as monotherapy. A total of 51 patients with cT1c-T3aN0M0 prostate cancer treated between July 2007 and January 2010 were included in this study. The average age was 69?years, and the average initial serum prostate-specific antigen was 10.98?ng/mL. A total of 25, 18 and eight patients were considered to be low, intermediate and high risk, respectively. All patients received one implant of Ir-192 and seven fractions of 6.5?Gy within 3.5?days for a total prescribed dose of 45.5?Gy. For high-risk prostate cancer, neoadjuvant androgen deprivation therapy was carried out for at least 6?months, and continued after high-dose-rate brachytherapy. Quality of life outcomes were measured by using the International Prostate Symptom Score, the Functional Assessment of Cancer Therapy-Prostate and the International Index of Erectile Function Questionnaire. The oncological outcome was assessed by serum prostate-specific antigen and diagnostic imaging. Adverse events were also recorded. The Functional Assessment of Cancer Therapy-Prostate scores decreased for a few months after high-dose-rate brachytherapy, and recovered to pretreatment condition thereafter. The International Prostate Symptom Score significantly increased 2?weeks after treatment for each of its items and their sum, and it returned to baseline after 12?weeks. Sexual function decreased at 2 and 4?weeks, and recovered after 12?weeks. Severe complications were rare. Within a median follow up of 17.2?months, two patients showed a prostate-specific antigen recurrence. High-dose-rate brachytherapy for prostate cancer is a feasible treatment modality with acceptable toxicity and only a limited impact on the quality of life. (author)

  20. High dose rate interstitial brachytherapy with external beam irradiation for localized prostate cancer. Preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Hiratsuka, Junichi; Jo, Yoshimasa; Yoden, Eisaku; Tanaka, Hiroyoshi; Imajo, Yoshinari [Kawasaki Medical School, Kurashiki, Okayama (Japan); Nagase, Naomi; Narihiro, Naomasa; Kubota, Juichi

    2000-12-01

    This study was undertaken to assess the biochemical and pathological results of combined external beam radiotherapy and high dose rate Ir-192 brachytherapy (HDR-Ir192) for clinically localized prostate cancer. Between October 1997 and August 1999, 39 evaluable patients with adenocarcinoma of prostate diagnosed by biopsy were treated with interstitial and external beam irradiation. Patients ranged in age from 58-82 years, with a mean of 69.7 years. T1c, T2 and T3 tumors, according to the UICC classification system (1997), were found in 7, 21 and 11 cases respectively. The mean initial pre-treatment PSA was 35.9 ng/ml (median 13.2), with 77% of the patients having had a pre-treatment PSA greater than 10 ng/ml. Of all patients, 17 had received pre-treatment hormonal therapy. Hormonal pretreatment was stopped at the beginning of radiotherapy in all cases. External beam four-field box irradiation was given to the small pelvis to a dose of 45 Gy/25 fractions. Three HDR-Ir192 treatments were given over a 30-h period, with 5.5 Gy per fraction at the circumference of the prostate gland over the course of this study. Biochemical failure was defined as a PSA level >1.5 ng/ml and rising on three consecutive values. If serial post-treatment PSA levels showed a continuous downward trend, failure was not scored. The patient with clinical evidence of progression was classified as a clinical failure. The median follow-up at the time of evaluation was 19.6 months. A post-treatment PSA level {<=}1.0 ng/ml was seen in 26 (67%) patients, and values from >1.0 to {<=}2.0 ng/ml were seen in 10 (26%) patients. Biochemical failure was not seen in 38 patients except for one patient who developed a distant bone metastasis with negative prostatic biopsy 15 months after treatment. Biochemical control rate was 100% (38/38) except for the patient with bone metastasis classified as clinical failure. Negative biopsies 18 months after treatment were found in 93% (14/15) of patients. Only one patient

  1. Postoperative vaginal cuff irradiation using high dose rate remote afterloading: a Phase II clinical protocol

    International Nuclear Information System (INIS)

    Noyes, William R.; Bastin, Kenneth; Edwards, Scott A.; Buchler, Dolores A.; Stitt, Judith A.; Thomadsen, Bruce R.; Fowler, Jack F.; Kinsella, Timothy J.

    1995-01-01

    Purpose: In September 1989, a postoperative Phase II high dose rate (HDR) brachytherapy protocol was started for International Federation of Gynecology and Obstetrics (FIGO) Stage I endometrial adenocarcinoma. This review reports the overall survival, local control, and complication rates for the initial 63 patients treated in this Phase II study. Methods and Materials: High dose rate brachytherapy was delivered using an Iridium-192 HDR remote afterloader. Sixty-three patients were entered into the Phase II protocol, each receiving two vaginal cuff treatments 1 week apart (range 4-12 days) with vaginal ovoids (diameter 2.0-3.0 cm). No patient received adjuvant external beam radiation. A dose of 32.4 Gy in two fractions was prescribed to the ovoid surface in 63 patients. The first three patients treated at our institution received 15, 16.2, and 29 Gy, respectively, to determine acute effects. Results: At a median follow-up of 1.6 years (range 0.75-4.3 years) no patient has developed a vaginal cuff recurrence. One regional recurrence (1.6%) occurred at 1.2 years at the pelvic side wall. This patient is alive and without evidence of disease 7 months after completion of salvage irradiation, which resulted in the only vaginal stenosis (1.6%). Fourteen patients (22%) experienced vaginal apex fibrosis by physical exam, which was clinically symptomatic in four patients. Two patients reported stress incontinence; however, these symptoms were noted prior to their HDR therapy. One patient died 2.4 years after HDR therapy due to cardiovascular disease without evidence of cancer at autopsy. Conclusion: Preliminary results of our phase II HDR vaginal cuff protocol for postoperative FIGO Stage IA, Grade 3 or Stage IB, Grade 1-2 patients demonstrate that 32.4 Gy in two fractions is well tolerated by the vaginal cuff mucosa. Local control appears comparable to our prior experience and others with low dose rate (LDR) brachytherapy. Additional patient accrual and further follow

  2. Dynamic changes of peripheral blood T-lymphocyte DNA-Synthesis in rabbits after fractionated and single exposure to 60Co-γ rays

    International Nuclear Information System (INIS)

    Wang Zongwu; Chen Tiehe; Yu Zhijie; Han Ling; Pan Yusha; Su Fuqiang

    1988-01-01

    The experiments in 59 rabbits γ-irradiated with doses of 0, 0.5, 1.0, 2.0, and 3.0 Gy in fractional and single exposure to 60 Co-γ rays were reported, respectively · Dynamics of the changes of DNA-Synthesis in T-lymphocytes of peripheral blood was obserced during 29 days after γ-irradiation. Marked inhibition in DNA-synthesis was found on 1st day after irradiation. Recovery was observed in 3rd day after irradiation. The levels of DNA-synthesis before irradiation was recovered on 7th day after exposure for all groups. For fractionated irradiation, however, an increase, rather than a decrese, of DNA-synthesis was in the group of 1.0 Gy

  3. Hit-size effectiveness theory applied to high doses of low LET radiation for pink mutations in Tradescantia

    International Nuclear Information System (INIS)

    Varma, M.N.; Bond, V.P.; Matthews, G.

    1985-01-01

    A hit-size effectiveness function which represents the probability of inducing a pink mutation in Tradescantia as a function of lineal energy density has been obtained (1) using observed pink mutation data for seven different radiation qualities and their respective single event microdosimetric spectra. In obtaining this function only the linear portions of dose-response curves were used. A significant improvement of the concepts embodied in the proposed hit-size effectiveness theory would be the demonstration of its applicability at high doses (where multiple hits are produced) and high dose rates (at which no significant biological repair takes place). In this article details are given on preliminary calculations of the pink mutation frequency in Tradescantia at 1, 5, 10, 20, and 60 rads for 250 kVp x rays, using the multi-hit spectra and the hit-size effectiveness function obtained on the basis of single hit microdosimetric spectra as outline in (1). A comparison of the calculated and observed pink mutation frequencies indicate excellent agreement and suggests the possibility of obtaining the hit-size effectiveness function from high dose biological-effect data obtained using low-LET radiations. 6 refs., 3 figs., 3 tabs

  4. 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.

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

    International Nuclear Information System (INIS)

    Yoshioka, Yasuo; Kotsuma, Tadayuki; Komiya, Akira; Kariya, Shinji; Konishi, Koji; Nonomura, Norio; Ogawa, Kazuhiko; Tanaka, Eiichi; Nishimura, Kensaku; Fujiuchi, Yasuyoshi; Kitamura, Hiroshi; Yamagami, Takuji; Yamasaki, Ichiro; Nishimura, Kazuo; Teshima, Teruki; Nakamura, Katsumasa; Itami, Jun

    2017-01-01

    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 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.

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

    International Nuclear Information System (INIS)

    Guinot, Jose-Luis; Baixauli-Perez, Cristobal; Soler, Pablo; Tortajada, Maria Isabel; Moreno, Araceli; Santos, Miguel Angel; Mut, Alejandro; Gozalbo, Francisco; Arribas, Leoncio

    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

  7. 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

  8. High dose rate brachytherapy in treatment of high grade astrocytomas

    International Nuclear Information System (INIS)

    Garcia-Alejo, R.; Delgado, J.M.; Cerro, E. del; Torres, J.J.; Martinez, R.

    1996-01-01

    From May 1994 to June 1995, 18 patients with high grade astrocytomas were entered prospectively on a selective protocol combining surgery, external beam radiotherapy, stereotactic interstitial implantation with HDR Iridium 192 and chemotherapy. Only those patients with tumor size 100cc or less average dimension, high grade astrocytoma, Karnofsky 70 or greater, unilateral, circumscribed, unifocal, tumor stable or responding to external radiation and supratentorial were included in the study. Ages ranged from 16 to 69 years. There were 13 males and 5 females. Surgery consisted of biopsy only in 3 patients, subtotal resection in 11, and gross total resection in 4 patients. Focal external beam radiation portals included the contrast enhancing mass on CT scan plus a 3 cm margin. The protocol called for minimum tumor dose of 60 Gy to be given in 2 Gy daily fractions. An interstitial brachytherapy boost was to be performed two weeks after the conclusion of external beam radiation. The dose was 30 Gy in 4 fractions. The authors analyze on basis on their personal experience, the possibilities and the limits offered by this therapeutic procedure in neuro-oncology. Using stereotactic techniques, interstitial brachytherapy of brain tumors was technically possible with negligible acute morbidity and mortality, and appeared to be effective and may provide for an increase in tumor control in selected cases

  9. 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

  10. 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

  11. High dose rate 192Ir calibration: Indonesia experiences

    International Nuclear Information System (INIS)

    Nasukha; Tjiptanto, D.; Darmasyah, R.; Kurniawan, B.

    2002-01-01

    Indonesia with a population of more than 200 Million people which spread on about 5000 islands, up to now only has 23 radiotherapy centers and some not active anymore. As mention by Parkin et al that Cervix/Utery and breast cancer are the most estimated numbers of new cases of cancers in women for developing countries, stomach and lung cancers in men. Indonesia as a developing country is likely similar to other developing countries on numbers of new cases of cancers in women. But quite different in men, in Indonesia the most common cancers are nasopharynx and thyroid cancers. The use of lr-192 sources in high dose-rate (HDR) remotely afterloaded brachytherapy treatments have greatly increased in recent years and variety of such sources are commercially available. Nine radiotherapy centers in Indonesia installed Nucletron microSelectron HDR remote afterloader. Based on the data of CiptoMangunkusurno Hospital, Jakarta that the most common cancers are the cervix, breast, nasopharynx and thyroid cancers which of percentage are about 31%, 25 %, 13%, and 6 % respectively. It means that the use of HDR 192 Ir brachytherapy has to be an effective tool in the treatments. Two methods have been studied and applied to calibrate HDR 192 Ir brachytherapy in Indonesia, especially for Nucletron microSelectron HDR 192 lr remote afterloader brachytherapy. Calibration of HDR 192 Ir brachytherapy source has been done by Cavity lonization Chamber and with Well Type lonization Chamber. First, 0.6 cc of NE Farmer type dosimeter that was calibrated to 60 Co and 250 kV of x-rays in air kerma was used in this experiment. Position of measurement (detector and source) at the center of the room and about 1 meter from the floor. Eight variation of distances from 10 cm to 40 cms have been carried out measurement as recommended by IAEA-TECDOC-1079. Correction have been given for scatters, non-uniformity, and attenuation. To solve the problem of scatter correction factor was used Matlab programming

  12. Implementation of microsource high dose rate (mHDR) brachytherapy in developing countries

    International Nuclear Information System (INIS)

    2001-11-01

    Brachytherapy using remote afterloading of a single high dose rate 192 Ir microsource was developed in the 1970s. After its introduction to clinics, this system has spread rapidly among developed Member States and has become a highly desirable modality in cancer treatment. This technique is now gradually being introduced to the developing Member States. The 192 Ir sources are produced with a high specific activity. This results in a high dose rate (HDR) to the tumour and shorter treatment times. The high specific activity simultaneously results in a much smaller source (so-called micro source, around I mm in diameter) which may be easily inserted into tissue through a thin delivery tube, the so-called interstitial treatment, as well as easily inserted into body cavities, the so-called intracavitary or endoluminal treatment. Another advantage is the ability to change dwell time (the time a source remains in one position) of the stepping source which allows dose distribution to match the target volume more closely. The purpose of this TECDOC is to advise radiation oncologists, medical physicists and hospital administrators in hospitals which are planning to introduce 192 Ir microsource HDR (mHDR) remote afterloading systems. The document supplements IAEA-TECDOC-1040, Design and Implementation of a Radiotherapy Programme: Clinical, Medical Physics, Radiation Protection and Safety Aspects, and will facilitate implementation of this new brachytherapy technology, especially in developing countries. The operation of the system, 'how to use the system', is not within the scope of this document. This TECDOC is based on the recommendations of an Advisory Group meeting held in Vienna in April 1999

  13. Plasma methylphenidate concentrations in youths treated with high-dose osmotic release oral system formulation.

    Science.gov (United States)

    Stevens, Jonathan R; George, Robert A; Fusillo, Steven; Stern, Theodore A; Wilens, Timothy E

    2010-02-01

    Children and adolescents are being treated increasingly for attention-deficit/hyperactivity disorder (ADHD) with a variety of stimulants in higher than Food and Drug Administration (FDA)-approved doses and in combination with other medications. We sought to determine methylphenidate (MPH) concentrations in children and adolescents treated with high-dose, extended-release osmotic release oral system (OROS) MPH plus concomitant medications, and to examine MPH concentrations with respect to the safety and tolerability of treatment. Plasma MPH concentrations were measured by liquid chromatography-mass spectrometry 4-5 hours after administration of medication in a sample of youths diagnosed with ADHD. These youths were treated naturalistically with higher than FDA-approved doses of OROS MPH in addition to their concomitant medications. Markers of safety and tolerability (e.g., measures of blood pressure and heart rate) were also examined. Among the 17 patients (with a mean age of 16.2 +/- 2 years and a mean number of concurrent medications of 2.23 +/- 0.94), the mean plasma MPH concentration was 28 +/- 9.1 ng/mL, despite a mean daily dose of OROS MPH of 169 +/- 5 mg (3.0 +/- 0.8 mg/kg per day). No patient had a plasma MPH level >or=50 ng/mL or clinical signs of stimulant toxicity. No correlation was found between plasma MPH concentrations and OROS MPH dose or changes in vital signs. High-dose OROS MPH, used in combination with other medications, was not associated with either unusually elevated plasma MPH concentrations or with clinically meaningful changes in vital signs. Study limitations include a single time-point sampling of MPH concentrations, a small sample size, and a lack of outcome measures to address treatment effectiveness.

  14. 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 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 hours. Results 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/70kg 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. Conclusions High doses of DXM produced effects distinct from triazolam and had characteristics that were similar to the classic hallucinogen psilocybin. PMID:22526529

  15. Usefulness of high-dose intravenous human immunoglobulins treatment for refractory recurrent pericarditis.

    Science.gov (United States)

    Moretti, Michele; Buiatti, Alessandra; Merlo, Marco; Massa, Laura; Fabris, Enrico; Pinamonti, Bruno; Sinagra, Gianfranco

    2013-11-01

    The management of refractory recurrent pericarditis is challenging. Previous clinical reports have noted a beneficial effect of high-dose intravenous human immunoglobulins (IvIgs) in isolated and systemic inflammatory disease-related forms. In this article, we analyzed retrospectively our clinical experience with IvIg therapy in a series of clinical cases of pericarditis refractory to conventional treatment. We retrospectively analyzed 9 patients (1994 to 2010) with refractory recurrent pericarditis, who received high-dose IvIg as a part of their medical treatment. Nonsteroidal anti-inflammatory drugs (NSAIDs), steroids, or colchicine treatment was not discontinued during IvIg treatment. No patients had a history of autoimmune or connective tissue diseases. During an average period of 11 months from the first recurrence, patients had experienced a mean of 5 relapses before the first IvIg treatment. In 4 cases, patients showed complete clinical remission with no further relapse after the first IvIg cycle. Two patients experienced a single minor relapse, responsive to short-term nonsteroidal anti-inflammatory drugs. In 2 patients, we performed a second cycle of IvIg after a recurrence of pericarditis, with subsequent complete remission. One patient did not respond to 3 cycles of IvIg and subsequently underwent pericardial window and long-term immunosuppressive treatment. No major adverse effect was observed in consequence of IvIg administration in all the cases. In conclusion, although IvIg mode of action is still poorly understood in this setting, this treatment can be considered as an option in patients with recurrent pericarditis refractory to conventional medical treatment and, in our small series, has proved to be effective in 8 of 9 cases. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Nelson's syndrome: single centre experience using the linear accelerator (LINAC) for stereotactic radiosurgery and fractionated stereotactic radiotherapy.

    Science.gov (United States)

    Wilson, Peter J; Williams, Janet R; Smee, Robert I

    2014-09-01

    Nelson's syndrome is a unique clinical phenomenon of growth of a pituitary adenoma following bilateral adrenalectomies for the control of Cushing's disease. Primary management is surgical, with limited effective medical therapies available. We report our own institution's series of this pathology managed with radiation: prior to 1990, 12 patients were managed with conventional radiotherapy, and between 1990 and 2007, five patients underwent stereotactic radiosurgery (SRS) and two patients fractionated stereotactic radiotherapy (FSRT), both using the linear accelerator (LINAC). Tumour control was equivocal, with two of the five SRS patients having a reduction in tumour volume, one patient remaining unchanged, and two patients having an increase in volume. In the FSRT group, one patient had a decrease in tumour volume whilst the other had an increase in volume. Treatment related morbidity was low. Nelson's syndrome is a challenging clinical scenario, with a highly variable response to radiation in our series. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Cushing's disease: a single centre's experience using the linear accelerator (LINAC) for stereotactic radiosurgery and fractionated stereotactic radiotherapy.

    Science.gov (United States)

    Wilson, P J; Williams, J R; Smee, R I

    2014-01-01

    Cushing's disease is hypercortisolaemia secondary to an adrenocorticotrophic hormone secreting pituitary adenoma. Primary management is almost always surgical, with limited effective medical interventions available. Adjuvant therapy in the form of radiation is gaining popularity, with the bulk of the literature related to the Gamma Knife. We present the results from our own institution using the linear accelerator (LINAC) since 1990. Thirty-six patients who underwent stereotactic radiosurgery (SRS), one patient who underwent fractionated stereotactic radiotherapy (FSRT) and for the purposes of comparison, 13 patients who had undergone conventional radiotherapy prior to 1990, were included in the analysis. Serum cortisol levels improved in nine of 36 (25%) SRS patients and 24 hour urinary free cortisol levels improved in 13 of 36 patients (36.1%). Tumour volume control was excellent in the SRS group with deterioration in only one patient (3%). The patient who underwent FSRT had a highly aggressive tumour refractory to radiation. Published by Elsevier Ltd.

  18. 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)

  19. On the impact of improved dosimetric accuracy on head and neck high dose rate brachytherapy.

    Science.gov (United States)

    Peppa, Vasiliki; Pappas, Eleftherios; Major, Tibor; Takácsi-Nagy, Zoltán; Pantelis, Evaggelos; Papagiannis, Panagiotis

    2016-07-01

    To study the effect of finite patient dimensions and tissue heterogeneities in head and neck high dose rate brachytherapy. The current practice of TG-43 dosimetry was compared to patient specific dosimetry obtained using Monte Carlo simulation for a sample of 22 patient plans. The dose distributions were compared in terms of percentage dose differences as well as differences in dose volume histogram and radiobiological indices for the target and organs at risk (mandible, parotids, skin, and spinal cord). Noticeable percentage differences exist between TG-43 and patient specific dosimetry, mainly at low dose points. Expressed as fractions of the planning aim dose, percentage differences are within 2% with a general TG-43 overestimation except for the spine. These differences are consistent resulting in statistically significant differences of dose volume histogram and radiobiology indices. Absolute differences of these indices are however small to warrant clinical importance in terms of tumor control or complication probabilities. The introduction of dosimetry methods characterized by improved accuracy is a valuable advancement. It does not appear however to influence dose prescription or call for amendment of clinical recommendations for the mobile tongue, base of tongue, and floor of mouth patient cohort of this study. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  20. High-dose-rate brachytherapy alone post-hysterectomy for endometrial cancer

    International Nuclear Information System (INIS)

    MacLeod, Craig; Fowler, Allan; Duval, Peter; D'Costa, Ieta; Dalrymple, Chris; Firth, Ian; Elliott, Peter; Atkinson, Ken; Carter, Jonathan

    1998-01-01

    Purpose: To evaluate the outcome of post-hysterectomy adjuvant vaginal high-dose-rate (HDR) brachytherapy. Methods and Materials: A retrospective analysis was performed on a series of 143 patients with endometrial cancer treated with HDR brachytherapy alone post-hysterectomy from 1985 to June 1993. Of these patients, 141 received 34 Gy in four fractions prescribed to the vaginal mucosa in a 2-week period. The median follow-up was 6.9 years. Patients were analyzed for treatment parameters, survival, local recurrence, distant relapse, and toxicity. Results: Five-year relapse free survival and overall survival was 100% and 88% for Stage 1A, 98% and 94% for Stage IB, 100% and 86% for Stage IC, and 92% and 92% for Stage IIA. The overall vaginal recurrence rate was 1.4%. The overall late-toxicity rate was low, and no RTOG grade 3, 4, or 5 complications were recorded. Conclusion: These results are similar to reported international series that have used either low-dose-rate or HDR brachytherapy. The biological effective dose was low for both acute and late responding tissues compared with some of the HDR brachytherapy series, and supports using this lower dose and possibly decreasing late side-effects with no apparent increased risk of vaginal recurrence

  1. X-ray photoelectron spectroscopy characterization of high dose carbon-implanted steel and titanium alloys

    Science.gov (United States)

    Viviente, J. L.; García, A.; Alonso, F.; Braceras, I.; Oñate, J. I.

    1999-04-01

    A study has been made of the depth dependence of the atomic fraction and chemical bonding states of AISI 440C martensitic stainless steel and Ti-6Al-4V alloy implanted with 75 keV C + at very high doses (above 10 18 ions cm -2), by means of X-ray photoelectron spectroscopy combined with an Ar + sputtering. A Gaussian-like carbon distribution was observed on both materials at the lowest implanted dose. More trapezoidal carbon depth-profiles were found with increasing implanted doses, and a pure carbon layer was observed only on the titanium alloy implanted at the highest dose. The implanted carbon was combined with both base metal and carbon itself to form metallic carbides and graphitic carbon. Furthermore, carbon-enriched carbides were also found by curve fitting the C 1s spectra. The titanium alloy showed a higher carbidic contribution than the steel implanted at the same C + doses. A critical carbon concentrations of about 33 at.% and 23 at.% were measured for the formation of C-C bonds in Ti-6Al-4V and steel samples, respectively. The carbon atoms were bound with metal to form carbidic compounds until these critical concentrations were reached; when this C concentration was exceeded the proportion of C-C bonds increased and resulted in the growth of carbonaceous layers.

  2. Survival of tumor cells after proton irradiation with ultra-high dose rates

    International Nuclear Information System (INIS)

    Auer, Susanne; Hable, Volker; Greubel, Christoph; Drexler, Guido A; Schmid, Thomas E; Belka, Claus; Dollinger, Günther; Friedl, Anna A

    2011-01-01

    Laser acceleration of protons and heavy ions may in the future be used in radiation therapy. Laser-driven particle beams are pulsed and ultra high dose rates of >10 9 Gy s -1 may be achieved. Here we compare the radiobiological effects of pulsed and continuous proton beams. The ion microbeam SNAKE at the Munich tandem accelerator was used to directly compare a pulsed and a continuous 20 MeV proton beam, which delivered a dose of 3 Gy to a HeLa cell monolayer within < 1 ns or 100 ms, respectively. Investigated endpoints were G2 phase cell cycle arrest, apoptosis, and colony formation. At 10 h after pulsed irradiation, the fraction of G2 cells was significantly lower than after irradiation with the continuous beam, while all other endpoints including colony formation were not significantly different. We determined the relative biological effectiveness (RBE) for pulsed and continuous proton beams relative to x-irradiation as 0.91 ± 0.26 and 0.86 ± 0.33 (mean and SD), respectively. At the dose rates investigated here, which are expected to correspond to those in radiation therapy using laser-driven particles, the RBE of the pulsed and the (conventional) continuous irradiation mode do not differ significantly

  3. Hypofractionated High-Dose Irradiation with Positron Emission Tomography Data for the Treatment of Glioblastoma Multiforme

    Directory of Open Access Journals (Sweden)

    Kazuhiro Miwa

    2014-01-01

    Full Text Available This research paper presents clinical outcomes of hypofractionated high-dose irradiation by intensity-modulated radiation therapy (Hypo-IMRT with 11C-methionine positron emission tomography (MET-PET data for the treatment of glioblastoma multiforme (GBM. A total of 45 patients with GBM were treated with Hypo-IMRT after surgery. Gross tumor volume (GTV was defined as the area of enhanced lesion on MRI, including MET-PET avid region; clinical target volume (CTV was the area with 5 mm margin surrounding the GTV; planning target volume (PTV was the area with 15 mm margin surrounding the CTV, including MET-PET moderate region. Hypo-IMRT was performed in 8 fractions; planning the dose for GTV was escalated to 68 Gy and that for CTV was escalated to 56 Gy, while keeping the dose delivered to the PTV at 40 Gy. Concomitant and adjuvant TMZ chemotherapy was administered. At a median follow-up of 18.7 months, median overall survival (OS was 20.0 months, and median progression-free survival was 13.0 months. The 1- and 2-year OS rates were 71.2% and 26.3%, respectively. Adjuvant TMZ chemotherapy was significantly predictive of OS on multivariate analysis. Late toxicity included 7 cases of Grade 3-4 radiation necrosis. Hypo-IMRT with MET-PET data appeared to result in favorable survival outcomes for patients with GBM.

  4. The Change of the Salivary Function after the High Dose Radioiodine Treatment in the patients with Differentiated Thyroid Cancer

    International Nuclear Information System (INIS)

    Lim, S. M.; Hong, S. W.; Lee, J. O.; Kang, T. W.

    1989-01-01

    The pain, swelling of salivary glands and dry mouth are not infrequent complication of the high dose radioiodine treatment in the patients with differentiated thyroid cancer. The purpose of this study was, by the dynamic salivary scintigraphy, to observe the change of the salivary function after the high dose (150-200 mCi) radioiodine treatment. From May 1987 to April 1988, the dynamic salivary scintigraphy with 5 mCi of 99m Tc-pertechnetate and gamma camera was performed before and 7 days after the radioiodine treatment in 7 patients with differentiated thyroid cancer. Just after the dynamic scintigraphy, the stimulation test with vitamin C solution of pH 3.0 and poststimulation scintigraphy were done, and the radioactivity uptake index, excretion fraction and salivary clearance after the stimulation were calculated for each gland. There was positive correlation between the radioactivity uptake index and excretion fraction after the stimulation. The salivary clearance after the stimulation was 18.96 ± 8.95 ml/min in the pretreatment state, and 14.37 ± 7.7 ml/min after the radioiodine treatment. After the radioiodine treatment, the radioactivity uptake index, excretion fraction and salivary clearance after the stimulation were significantly reduced in the parotid glands, but only the excretion fraction was reduced in the submandibular glands. The more the pretreatment salivary clearance after the stimulation was, the % change after the treatment was smaller. Further studies on the relation between the radiation dose in the salivary glands and the change of their function, and the long-term observation for the recovery of function are expected.

  5. A consideration of distributions and treatment schedules in high dose rate intracavitary therapy of carcinoma of the uterine cervix

    International Nuclear Information System (INIS)

    Sakata, Suoh; Sato, Sigehiro; Nakano, Masao; Iida, Koyo; Yui, Nobuharu

    1979-01-01

    A remotely controlled afterloading device for high dose rate intracavitary radiation, the remote afterloader Shimadzu Ralstron MTSW-20, was installed at Chiba Cancer Center Hospital in 1973 and put into clinical use for the treatment of carcinoma of the uterine cervix. Before the clinical use, isodose distributions and treatment schedules were investigated, compared with the low dose rate intracavitary radiation by linear sources of 137 Cs used hitherto. The isodose distributions, calculated by using an electronic computer, for various combinations of the length of uterine canal and the separation of vaginal applicators, were the same as those obtained with linear sources. As for the treatment schedules, by using PT (partial tolerance) which was derived from NSD concept of Ellis, a number of fractional radiation regimes with high dose rate, equivalent to continuous low dose rate radiation, was calculated. From these, a dose of 600 rad per fraction to point A every week has been chosen as the standard radiation schedule. The number of fractions has been varied with the clinical stages. Furthermore, some changes of total dose or small modification of dose distribution have been made for individual lesions. According to the preliminary results, three-year cumulative survival rate was 68.7% and complication rate was 15.2%. Comparing these results with those of the treatment at low dose rate, the former is nearly equal, while the latter is lower. The reduction of complication rate is probably due to the improvement of therapeutic techniques such as continuous observation by fractionated intracavitary radiation, variety of isodose distributions and accuracy of source placement by a short treatment time. (author)

  6. Transport properties of PrxOs4Sb12 single crystals with high Pr-site filling fraction grown under high pressure

    International Nuclear Information System (INIS)

    Tanaka, Kenya; Namiki, Takahiro; Saito, Takashi; Tatsuoka, Sho; Imamura, Atsushi; Kuwahara, Keitaro; Aoki, Yuji; Sato, Hideyuki

    2009-01-01

    We have succeeded in growing Pr x Os 4 Sb 12 single crystals under ∼4GPa with high Pr-site filling fraction x. The electrical resistance measurements clearly show that the superconducting (SC) transition is sharper and the onset temperatures is lower in the single crystal samples grown under high pressure compared to that of the sample grown under ambient pressure. These results suggest that the double SC transition ascribed to sample inhomogeneity is suppressed in the sample grown under high pressure. The change of 4f-electron crystalline electric field energy splitting between the Γ 1 ground state and the Γ 4 (2) first excited state in the sample made under high pressure is proposed as one of the possible origins of the suppression of the double SC transition.

  7. Complete resolution of minocycline pigmentation following a single treatment with non-ablative 1550-nm fractional resurfacing in combination with the 755-nm Q-switched alexandrite laser.

    Science.gov (United States)

    Vangipuram, Ramya K; DeLozier, Whitney L; Geddes, Elizabeth; Friedman, Paul M

    2016-03-01

    Pigmentation secondary to minocycline ingestion is an uncommon adverse event affecting 3.7-14.8% of treated individuals for which few effective therapies are available. Three patterns of minocycline pigmentation have a characteristic clinical and histological appearance. The pigment composition in each variety is different and occurs at varying skin depths. Accordingly, a tailored approach according to the type of minocycline pigmentation is crucial for treatment success. The purpose of this intervention was to evaluate the efficacy of non-ablative fractional photothermolysis in combination with the Q-switched alexandrite laser for the treatment of type I minocycline pigmentation on the face. A patient with type I minocycline pigmentation was treated with non-ablative 1550-nm fractional photothermolysis followed immediately by 755-nm Q-switched alexandrite laser and then observed clinically to determine the outcome of this modality. The patient was seen in clinic 1 month later following her single treatment session and 100% clearance of all blue facial pigment was observed. Non-ablative fractional photothermolysis in combination with the 755-nm Q-switched alexandrite laser should be considered for treatment of type I minocycline pigmentation. © 2015 Wiley Periodicals, Inc.

  8. High-Dose-Rate Brachytherapy Alone for Localized Prostate Cancer in Patients at Moderate or High Risk of Biochemical Recurrence

    Energy Technology Data Exchange (ETDEWEB)

    Hoskin, Peter [Cancer Centre, Mount Vernon Hospital, Northwood, Middlesex (United Kingdom); Rojas, Ana, E-mail: arc03@btconnect.com [Cancer Centre, Mount Vernon Hospital, Northwood, Middlesex (United Kingdom); Lowe, Gerry; Bryant, Linda; Ostler, Peter; Hughes, Rob; Milner, Jessica; Cladd, Helen [Cancer Centre, Mount Vernon Hospital, Northwood, Middlesex (United Kingdom)

    2012-03-15

    Purpose: To evaluate genitourinary (GU) and gastrointestinal (GI) morbidity and biochemical control of disease in patients with localized prostate adenocarcinoma treated with escalating doses per fraction of high-dose rate brachytherapy alone. Methods and Materials: A total of 197 patients were treated with 34 Gy in four fractions, 36 Gy in four fractions, 31.5 Gy in three fractions, or 26 Gy in two fractions. Median follow-up times were 60, 54, 36, and 6 months, respectively. Results: Incidence of early Grade {>=} 3 GU morbidity was 3% to 7%, and Grade 4 was 0% to 4%. During the first 12 weeks, the highest mean International Prostate Symptom Score (IPSS) value was 14, and between 6 months and 5 years it was 8. Grade 3 or 4 early GI morbidity was not observed. The 3-year actuarial rate of Grade 3 GU was 3% to 16%, and was 3% to 7% for strictures requiring surgery (4-year rate). An incidence of 1% Grade 3 GI events was seen at 3 years. Late Grade 4 GU or GI events were not observed. At 3 years, 99% of patients with intermediate-risk and 91% with high-risk disease were free of biochemical relapse (log-rank p = 0.02). Conclusions: There was no significant difference in urinary and rectal morbidity between schedules. Biochemical control of disease in patients with intermediate and high risk of relapse was good.

  9. Assessing patient characteristics and radiation-induced non-targeted effects in vivo for high dose-rate (HDR) brachytherapy.

    Science.gov (United States)

    Pinho, Christine; Timotin, Emilia; Wong, Raimond; Sur, Ranjan K; Hayward, Joseph E; Farrell, Thomas J; Seymour, Colin; Mothersill, Carmel

    2015-01-01

    To test whether blood, urine, and tissue based colony-forming assays are a useful clinical detection tool for assessing fractionated treatment responses and non-targeted radiation effects in bystander cells. To assess patients' responses to radiation treatments, blood serum, urine, and an esophagus explant-based in vivo colony-forming assay were used from oesophageal carcinoma patients. These patients underwent three fractions of high dose rate (HDR) intraluminal brachytherapy (ILBT). Human keratinocyte reporters exposed to blood sera taken after the third fraction of brachytherapy had a significant increase in cloning efficiency compared to baseline samples (p fractions for the blood sera data only. Patient characteristics such as gender had no statistically significant effect (p > 0.05). Large variability was observed among the patients' tissue samples, these colony-forming assays showed no significant changes throughout fractionated brachytherapy (p > 0.05). Large inter-patient variability was found in the urine and tissue based assays, so these techniques were discontinued. However, the simple blood-based assay had much less variability. This technique may have future applications as a biological dosimeter to predict treatment outcome and assess non-targeted radiation effects.

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

    International Nuclear Information System (INIS)

    Demanes, D. Jeffrey; Martinez, Alvaro A.; Ghilezan, Michel; Hill, Dennis R.; Schour, Lionel; Brandt, David; Gustafson, Gary

    2011-01-01

    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.

  11. Late complications after high-dose-rate interstitial brachytherapy for tongue cancer

    International Nuclear Information System (INIS)

    Shimizutani, Kimishige; Inoue, Takehiro; Inoue, Toshihiko; Yoshioka, Yasuo; Teshima, Teruki; Kakimoto, Naoya; Murakami, Shumei; Furukawa, Souhei; Fuchihata, Hajime

    2005-01-01

    The objectives of this study was to analyze the treatment results and late complications of high-dose-rate (HDR) interstitial brachytherapy (ISBT) for early (T1N0, T2N0) mobile tongue cancer using the microSelectron-HDR. From January 1993 through April 2001, a total of 72 patients with early squamous cell carcinomas of the mobile tongue were treated with microSelectron-HDR interstitial brachytherapy at the Department of Radiology, Osaka University Hospital. Of the patients, 18% were treated with a combination of prior external radiation and HDR-ISBT, and 82% were treated with HDR-ISBT alone. For HDR-ISBT alone, all cases were treated with a total dose of 54 Gy/9 fractions every 5 days or 60 Gy/10 fractions every 8 days. In combined therapy with an external dose of 30 to 40 Gy, HDR-ISBT was given at a total dose of 42-50 Gy. The Brinkman and alcohol indexes were used to analyze the incidence of late complications after HDR-ISBT. The 2- and 5-year local control rates were 85% and 82%, respectively. Fifteen of 72 patients (21%) treated with HDR-ISBT had late complications. Ten of 15 patients (67%) with late complications had a Brinkman index exceeding 600. HDR-ISBT is useful and easily applied under local anesthesia to early or superficial lesions of the mobile tongue. However, we found an increase in late complications, such as soft-tissue ulcers and bone exposure, after irradiation of tongue cancer with 60 Gy HDR-ISBT in patients with a Brinkman index greater than 600. (author)

  12. Interfraction patient motion and implant displacement in prostate high dose rate brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Fox, C. D.; Kron, T.; Leahy, M.; Duchesne, G.; Williams, S.; Tai, K. H.; Haworth, A.; Herschtal, A.; Foroudi, F. [Department of Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, Victoria 3002 (Australia); Nursing Service, Peter MacCallum Cancer Centre, Melbourne, Victoria 3002 (Australia); Department of Radiation Oncology, Peter MacCallum Cancer Centre and University of Melbourne, Melbourne, Victoria 3002 (Australia); Department of Physical Sciences, Peter MacCallum Cancer Centre and Royal Melbourne Insititute of Technology, Melbourne, Victoria 3000 (Australia); Department of Biostatistics and Clinical Trials, Peter MacCallum Cancer Centre, Melbourne, Victoria 3002 (Australia); Department of Radiation Oncology, Peter MacCallum Cancer Centre and University of Melbourne, Melbourne, Victoria 3010 (Australia)

    2011-11-15

    Purpose: To quantify movement of prostate cancer patients undergoing treatment, using an in-house developed motion sensor in order to determine a relationship between patient movement and high dose rate (HDR) brachytherapy implant displacement. Methods: An electronic motion sensor was developed based on a three axis accelerometer. HDR brachytherapy treatment for prostate is delivered at this institution in two fractions 24 h apart and 22 patients were monitored for movement over the interval between fractions. The motion sensors functioned as inclinometers, monitoring inclination of both thighs, and the inclination and roll of the abdomen. The implanted HDR brachytherapy catheter set was assessed for displacement relative to fiducial markers in the prostate. Angle measurements and angle differences over a 2 s time base were binned, and the standard deviations of the resulting frequency distributions used as a metric for patient motion in each monitored axis. These parameters were correlated to measured catheter displacement using regression modeling. Results: The mean implant displacement was 12.6 mm in the caudal direction. A mean of 19.95 h data was recorded for the patient cohort. Patients generally moved through a limited range of angles with a mean of the exception of two patients who spent in excess of 2 h lying on their side. When tested for a relationship between movement in any of the four monitored axes and the implant displacement, none was significant. Conclusions: It is not likely that patient movement influences HDR prostate implant displacement. There may be benefits to patient comfort if nursing protocols were relaxed to allow patients greater freedom to move while the implant is in situ.

  13. Interfraction patient motion and implant displacement in prostate high dose rate brachytherapy

    International Nuclear Information System (INIS)

    Fox, C. D.; Kron, T.; Leahy, M.; Duchesne, G.; Williams, S.; Tai, K. H.; Haworth, A.; Herschtal, A.; Foroudi, F.

    2011-01-01

    Purpose: To quantify movement of prostate cancer patients undergoing treatment, using an in-house developed motion sensor in order to determine a relationship between patient movement and high dose rate (HDR) brachytherapy implant displacement. Methods: An electronic motion sensor was developed based on a three axis accelerometer. HDR brachytherapy treatment for prostate is delivered at this institution in two fractions 24 h apart and 22 patients were monitored for movement over the interval between fractions. The motion sensors functioned as inclinometers, monitoring inclination of both thighs, and the inclination and roll of the abdomen. The implanted HDR brachytherapy catheter set was assessed for displacement relative to fiducial markers in the prostate. Angle measurements and angle differences over a 2 s time base were binned, and the standard deviations of the resulting frequency distributions used as a metric for patient motion in each monitored axis. These parameters were correlated to measured catheter displacement using regression modeling. Results: The mean implant displacement was 12.6 mm in the caudal direction. A mean of 19.95 h data was recorded for the patient cohort. Patients generally moved through a limited range of angles with a mean of the exception of two patients who spent in excess of 2 h lying on their side. When tested for a relationship between movement in any of the four monitored axes and the implant displacement, none was significant. Conclusions: It is not likely that patient movement influences HDR prostate implant displacement. There may be benefits to patient comfort if nursing protocols were relaxed to allow patients greater freedom to move while the implant is in situ.

  14. Brachytherapy for early oral tongue cancer. Low dose rate to high dose rate

    International Nuclear Information System (INIS)

    Yamazaki, Hideya; Inoue, Takehiro; Yoshida, Ken; Yoshioka, Yasuo; Shimizutani, Kimishige; Inoue, Toshihiko; Furukawa, Souhei; Kakimoto, Naoya

    2003-01-01

    To examine the compatibility of low dose rate (LDR) with high dose rate (HDR) brachytherapy, we reviewed 399 patients with early oral tongue cancer (T1-2N0M0) treated solely by brachytherapy at Osaka University Hospital between 1967 and 1999. For patients in the LDR group (n=341), the treatment sources consisted of Ir-192 pin for 227 patients (1973-1996; irradiated dose, 61-85 Gy; median, 70 Gy), Ra-226 needle for 113 patients (1967-1986; 55-93 Gy; median, 70 Gy). Ra-226 and Ir-192 were combined for one patient. Ir-192 HDR (microSelectron-HDR) was used for 58 patients in the HDR group (1991-present; 48-60 Gy; median, 60 Gy). LDR implantations were performed via oral and HDR via a submental/submandibular approach. The dose rates at the reference point for the LDR group were 0.30 to 0.8 Gy/h, and for the HDR group 1.0 to 3.4 Gy/min. The patients in the HDR group received a total dose of 48-60 Gy (8-10 fractions) during one week. Two fractions were administered per day (at least a 6-h interval). The 3- and 5-year local control rates for patients in the LDR group were 85% and 80%, respectively, and those in the HDR group were both 84%. HDR brachytherapy showed the same lymph-node control rate as did LDR brachytherapy (67% at 5 years). HDR brachytherapy achieved the same locoregional result as did LDR brachytherapy. A converting factor of 0.86 is applicable for HDR in the treatment of early oral tongue cancer. (author)

  15. The Role of High Dose Interleukin-2 in the Era of Targeted Therapy.

    Science.gov (United States)

    Gills, Jessie; Parker, William P; Pate, Scott; Niu, Sida; Van Veldhuizen, Peter; Mirza, Moben; Holzbeierlein, Jeffery M; Lee, Eugene K

    2017-09-01

    We assessed survival outcomes following high dose interleukin-2 in a contemporary cohort of patients during the era of targeted agents. We retrospectively reviewed the records of patients with metastatic renal cell carcinoma treated with high dose interleukin-2 between July 2007 and September 2014. Clinicopathological data were abstracted and patient response to therapy was based on RECIST (Response Evaluation Criteria In Solid Tumors), version 1.1 criteria. The Kaplan-Meier method was used to estimate progression-free and overall survival in the entire cohort, the response to high dose interleukin-2 in regard to previous targeted agent therapy and the response to the targeted agent in relation to the response to high dose interleukin-2. We identified 92 patients, of whom 87 had documentation of a response to high dose interleukin-2. Median overall survival was 34.4 months from the initiation of high dose interleukin-2 therapy in the entire cohort. Patients who received targeted therapy before high dose interleukin-2 had overall survival (median 34.4 and 30.0 months, p = 0.88) and progression-free survival (median 1.5 and 1.7 months, p = 0.8) similar to those in patients who received no prior therapy, respectively. Additionally, patients with a complete or partial response to high dose interleukin-2 had similar outcomes for subsequent targeted agents compared to patients whose best response was stable or progressive disease (median overall survival 30.1 vs 25.4 months, p = 0.4). Our data demonstrate that patient responses to high dose interleukin-2 and to targeted agents before and after receiving high dose interleukin-2 are independent. As such, carefully selected patients should be offered high dose interleukin-2 for the possibility of a complete and durable response without the fear of limiting the treatment benefit of targeted agents. Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  16. Differential uptake and oxidative stress response in zebrafish fed a single dose of the principal copper and zinc enriched sub-cellular fractions of Gammarus pulex

    International Nuclear Information System (INIS)

    Khan, Farhan R.; Bury, Nicolas R.; Hogstrand, Christer

    2010-01-01

    The sub-cellular compartmentalisation of trace metals and its effect on trophic transfer and toxicity in the aquatic food chain has been a subject of growing interest. In the present study, the crustacean Gammarus pulex was exposed to either 11 μg Cu l -1 , added solely as the enriched stable isotope 65 Cu, or 660 μg Zn l -1 , radiolabeled with 2MBq 65 Zn, for 16 days. Post-exposure the heat stable cytosol containing metallothionein-like proteins (MTLP) and a combined granular and exoskeletal (MRG + exo) fractions were isolated by differential centrifugation, incorporated into gelatin and fed to zebrafish as a single meal. Assimilation efficiency (AE) and intestinal lipid peroxidation, as malondialdehyde (MDA) were measured. There was a significant difference (p 65 Cu, although the results pointed towards greater bioavailability of the MTLP fraction compared to MRG + exo during the slow elimination phase (24-72 h) these results were not significant (p = 0.155). Neither zinc feed provoked a lipid peroxidation response in the intestinal tissue of zebrafish compared to control fish (gelatin fed), but both 65 Cu labeled feeds did. The greater effect was exerted by the MRG + exo (2.96 ± 0.29 nmol MDA mg protein -1 ) feed which three-fold greater than control (p -1 , p 109 Cd labeled G. pulex fractions were fed to zebrafish. Thus it appears that when a metal (Cu or Cd) has the potential to cause cytotoxicity via lipid peroxidation, a feed consisting of a largely unavailable fraction (MRG + exo) causes a greater intestinal stress response than the more bioavailable (MTLP) feed.

  17. Evaluation of Gafchromic EBT-XD film, with comparison to EBT3 film, and application in high dose radiotherapy verification

    Science.gov (United States)

    Palmer, Antony L.; Dimitriadis, Alexis; Nisbet, Andrew; Clark, Catharine H.

    2015-11-01

    There is renewed interest in film dosimetry for the verification of dose delivery of complex treatments, particularly small fields, compared to treatment planning system calculations. A new radiochromic film, Gafchromic EBT-XD, is available for high-dose treatment verification and we present the first published evaluation of its use. We evaluate the new film for MV photon dosimetry, including calibration curves, performance with single- and triple-channel dosimetry, and comparison to existing EBT3 film. In the verification of a typical 25 Gy stereotactic radiotherapy (SRS) treatment, compared to TPS planned dose distribution, excellent agreement was seen with EBT-XD using triple-channel dosimetry, in isodose overlay, maximum 1.0 mm difference over 200-2400 cGy, and gamma evaluation, mean passing rate 97% at 3% locally-normalised, 1.5 mm criteria. In comparison to EBT3, EBT-XD gave improved evaluation results for the SRS-plan, had improved calibration curve gradients at high doses, and had reduced lateral scanner effect. The dimensions of the two films are identical. The optical density of EBT-XD is lower than EBT3 for the same dose. The effective atomic number for both may be considered water-equivalent in MV radiotherapy. We have validated the use of EBT-XD for high-dose, small-field radiotherapy, for routine QC and a forthcoming multi-centre SRS dosimetry intercomparison.

  18. Evaluation of Gafchromic EBT-XD film, with comparison to EBT3 film, and application in high dose radiotherapy verification

    International Nuclear Information System (INIS)

    Palmer, Antony L; Dimitriadis, Alexis; Nisbet, Andrew; Clark, Catharine H

    2015-01-01

    There is renewed interest in film dosimetry for the verification of dose delivery of complex treatments, particularly small fields, compared to treatment planning system calculations. A new radiochromic film, Gafchromic EBT-XD, is available for high-dose treatment verification and we present the first published evaluation of its use. We evaluate the new film for MV photon dosimetry, including calibration curves, performance with single- and triple-channel dosimetry, and comparison to existing EBT3 film. In the verification of a typical 25 Gy stereotactic radiotherapy (SRS) treatment, compared to TPS planned dose distribution, excellent agreement was seen with EBT-XD using triple-channel dosimetry, in isodose overlay, maximum 1.0 mm difference over 200–2400 cGy, and gamma evaluation, mean passing rate 97% at 3% locally-normalised, 1.5 mm criteria. In comparison to EBT3, EBT-XD gave improved evaluation results for the SRS-plan, had improved calibration curve gradients at high doses, and had reduced lateral scanner effect. The dimensions of the two films are identical. The optical density of EBT-XD is lower than EBT3 for the same dose. The effective atomic number for both may be considered water-equivalent in MV radiotherapy. We have validated the use of EBT-XD for high-dose, small-field radiotherapy, for routine QC and a forthcoming multi-centre SRS dosimetry intercomparison. (paper)

  19. Extreme implanting in Si: A study of ion-induced damage at high temperature and high dose

    International Nuclear Information System (INIS)

    Holland, O.W.

    1994-01-01

    Ion-solid interactions near room temperature and below have been well studied in single-crystal Si. While this has led to a better understanding of the mechanisms responsible for nucleation and growth of lattice damage during irradiation, these studies have not, in general, been extended to high temperatures (e.g., >200 degrees C). This is the case despite the commercialization of ion beam technologies which utilize high-temperature processing, such as separation by implantation of oxygen (SIMOX). In this process, a silicon-on-insulator (SOI) material is produced by implanting a high dose of oxygen ions into a Si wafer to form a buried, stoichiometric oxide layer. Results will be presented of a study of damage accumulation during high-dose implantation of Si at elevated temperatures. In particular, O + -ions were used because of the potential impact of the results on the SIMOX technology. It will be shown that the nature of the damage accumulation at elevated temperatures is quite distinctive and portends the presence of a new mechanism, one which is only dominant under the extreme conditions encountered during ion beam synthesis (i.e., high temperature and high dose). This mechanism is discussed and shown to be quite general and not dependent on the chemical identity of the ions. Also, techniques for suppressing this mechanism by open-quotes defect engineeringclose quotes are discussed. Such techniques are technologically relevant because they offer the possibility of reducing the defect density of the SOI produced by SIMOX

  20. Mechanisms of Fatal Cardiotoxicity following High-Dose Cyclophosphamide Therapy and a Method for Its Prevention.

    Directory of Open Access Journals (Sweden)

    Takuro Nishikawa

    Full Text Available Observed only after administration of high doses, cardiotoxicity is the dose-limiting effect of cyclophosphamide (CY. We investigated the poorly understood cardiotoxic mechanisms of high-dose CY. A rat cardiac myocardial cell line, H9c2, was exposed to CY metabolized by S9 fraction of rat liver homogenate mixed with co-factors (CYS9. Cytotoxicity was then evaluated by 3-(4,5-dimethyl-2-thiazolyl¬2,5-diphenyl¬2H-tetrazolium bromide (MTT assay, lactate dehydrogenase release, production of reactive oxygen species (ROS, and incidence of apoptosis. We also investigated how the myocardial cellular effects of CYS9 were modified by acrolein scavenger N-acetylcysteine (NAC, antioxidant isorhamnetin (ISO, and CYP inhibitor β-ionone (BIO. Quantifying CY and CY metabolites by means of liquid chromatography coupled with electrospray tandem mass spectrometry, we assayed culture supernatants of CYS9 with and without candidate cardioprotectant agents. Assay results for MTT showed that treatment with CY (125-500 μM did not induce cytotoxicity. CYS9, however, exhibited myocardial cytotoxicity when CY concentration was 250 μM or more. After 250 μM of CY was metabolized in S9 mix for 2 h, the concentration of CY was 73.6 ± 8.0 μM, 4-hydroxy-cyclophosphamide (HCY 17.6 ± 4.3, o-carboxyethyl-phosphoramide (CEPM 26.6 ± 5.3 μM, and acrolein 26.7 ± 2.5 μM. Inhibition of CYS9-induced cytotoxicity occurred with NAC, ISO, and BIO. When treated with ISO or BIO, metabolism of CY was significantly inhibited. Pre-treatment with NAC, however, did not inhibit the metabolism of CY: compared to control samples, we observed no difference in HCY, a significant increase of CEPM, and a significant decrease of acrolein. Furthermore, NAC pre-treatment did not affect intracellular amounts of ROS produced by CYS9. Since acrolein seems to be heavily implicated in the onset of cardiotoxicity, any competitive metabolic processing of CY that reduces its transformation to acrolein

  1. High dose rate brachytherapy for the treatment of soft tissue sarcoma of the extremity

    International Nuclear Information System (INIS)

    Speight, J.L.; Streeter, O.E.; Chawla, S.; Menendez, L.E.

    1996-01-01

    Purpose: we examined the role of preoperative neoadjuvant chemoradiation and adjuvant high-dose rate brachytherapy on the management of prognostically unfavorable soft tissue sarcomas of the extremities. Our goal was to examine the effect of high dose rate interstitial brachytherapy (HDR IBT) on reducing the risk of local recurrence following limb-sparing resection, as well as shortening treatment duration. Materials and methods: eleven patients, ranging in age from 31 to 73 years old, with soft tissue sarcoma of the extremity were treated at USC/Norris Comprehensive Cancer Center during 1994 and 1995. All patients had biopsy proven soft tissue sarcoma, and all were suitable candidates for limb-sparing surgery. All lesions were greater than 5cm in size and were primarily high grade. Tumor histologies included malignant fibrous histiocytoma (45%), liposarcoma (18%) and leiomyosarcoma, synovial cell sarcoma and spindle cell sarcoma (36%). Sites of tumor origin were the lower extremity (55%), upper extremity (18%) and buttock (9%), 1 patient (9%) had lesions in both the upper and lower extremity. Patients received HDR IBT following combined chemotherapy and external beam irradiation (EBRT) and en bloc resection of the sarcoma. Neoadjuvant chemotherapy consisted of three to four cycles of either Ifosfamide/Mesna with or without Adriamycin, or Mesna, Adriamycin, Ifosfamide and Dacarbazine. One patient received Cis-platin in addition to Ifos/Adr. A minimum of two cycles of chemotherapy were administered prior to EBRT. Additional cycles of chemotherapy were completed concurrently with EBRT but prior to HDR IBT. Preoperative EBRT doses ranging from 40 to 59.4 Gy were given in daily fractions of 180 to 200cGy. Following en bloc resection, HDR IBT was administered using the Omnitron tm 2000 remote afterloading system. Doses ranging from 13 to 30 Gy were delivered to the surgical tumor bed at depths of 0.5mm to 0.75mm from the radioactive source. Results: median follow-up was

  2. The clinical pharmacology of alkylating agents in high-dose chemotherapy

    NARCIS (Netherlands)

    Huitema, A. D.; Smits, K. D.; Mathôt, R. A.; Schellens, J. H.; Rodenhuis, S.; Beijnen, J. H.

    2000-01-01

    Alkylating agents are widely used in high-dose chemotherapy regimens in combination with hematological support. Knowledge about the pharmacokinetics and pharmacodynamics of these agents administered in high doses is critical for the safe and efficient use of these regimens. The aim of this review is

  3. Risks Associated with High-Dose Lactobacillus rhamnosus in an Escherichia coli Model of Piglet Diarrhoea

    DEFF Research Database (Denmark)

    Li, Xiao-Qiong; Zhu, Yao-Hong; Zhang, Hong-Fu

    2012-01-01

    might be more effective than a high dose at ameliorating diarrhoea. There is a risk that high-dose L. rhamnosus pretreatment may negate the preventative effects, thus decreasing the prophylactic benefits against potential enteric pathogens. Our data suggest a safe threshold for preventative use...

  4. Split high-dose oral levothyroxine treatment as a successful therapy option in myxedema coma.

    Science.gov (United States)

    Charoensri, Suranut; Sriphrapradang, Chutintorn; Nimitphong, Hataikarn

    2017-10-01

    High-dose intravenous thyroxine (T4) is the preferable treatment for myxedema coma. We describe the clinical course of a 69-year-old man who presented with myxedema coma and received oral levothyroxine (LT4) therapy (1 mg) in a split dose. This suggests split high-dose oral LT4 as a therapeutic option in myxedema coma.

  5. Design and testing of an integrated electronically controlled capacitor for integral and fractional horse power single phase induction motor

    International Nuclear Information System (INIS)

    Faiz, Jawad; Kasebi, F.; Pillay, P.

    2004-01-01

    This paper addresses a problem that occurs in many small appliances. As such, it is an important problem of energy utilization. To improve the performance of a single phase capacitor start/run induction motor, FET type power transistors could be used to replace a SCR H bridge. Such a configuration can lead to a simpler and more inexpensive circuit for the electronically controlled capacitor. In this paper, ICs and an OP-AMP are used to design an electronically controlled capacitor for a single phase induction motor. The design can compensate for the input voltage fluctuations that are present in the normal operation of the motor. In addition, an improvement in its performance can be obtained. At present, the use of a tachometer can be considered a disadvantage of the proposed scheme. Thus, a configuration that enables removal of the tachometer, while maintaining reasonable cost, is desirable. In addition, replacing the ac capacitor with one rated for dc can lead to a system reduction, in addition to a considerable reduction in the size of the circuit due to the use of integrated circuits

  6. High-dose stabilized chlorite matrix WF10 prolongs cardiac xenograft survival in the hamster-to-rat model without inducing ultrastructural or biochemical signs of cardiotoxicity

    DEFF Research Database (Denmark)

    Hansen, A; Kemp, K; Kemp, E

    2001-01-01

    of high dose WF10 as a single drug regimen in the hamster-to-rat xenotransplantation model and searched for possible cardiotoxic side effects. WF10 prolonged cardiac xenograft survival, but did not induce tolerence or inhibit pathological signs of acute rejection. Hamsters from the donor population...

  7. Human tolerance to a single, high dose of D-tagatose.

    Science.gov (United States)

    Buemann, B; Toubro, S; Raben, A; Astrup, A

    1999-04-01

    The addition of 29 g D-tagatose added as a sweetener to a continental breakfast was tested for the appearance of gastrointestinal side effects in a double-blind randomized cross-over study with 29 g sucrose as a control treatment. The subjects reported the side effects during 72 h following the test meal on a questionnaire grading the symptoms on a five-level scale ranging from "none" to "very strong." Although "rumbling in the stomach," "distention," "nausea," "rumbling in the gut," "flatulence, " and "diarrhea" scored significantly higher with D-tagatose, the sugar otherwise was well tolerated in most of the subjects. Two cases of vomiting after D-tagatose were recorded but in one of the cases its relation to the D-tagatose intake was questionable. Only the "distention" score remained higher with D-tagatose for more than 24 h. Nausea, vomiting, and perceived distension may be due to an osmotic effect in the small intestine of unabsorbed