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Sample records for radiotherapy dvh analysis

  1. Comparison of DVH data from multiple radiotherapy treatment planning systems

    International Nuclear Information System (INIS)

    Ebert, M A; Kearvell, R; Hooton, B; Spry, N A; Bydder, S A; Joseph, D J; Haworth, A; Hug, B

    2010-01-01

    This study examined the variation of dose-volume histogram (DVH) data sourced from multiple radiotherapy treatment planning systems (TPSs). Treatment plan exports were obtained from 33 Australian and New Zealand centres during a dosimetry study. Plan information, including DVH data, was exported from the TPS at each centre and reviewed in a digital review system (SWAN). The review system was then used to produce an independent calculation of DVH information for each delineated structure. The relationships between DVHs extracted from each TPS and independently calculated were examined, particularly in terms of the influence of CT scan slice and pixel widths, the resolution of dose calculation grids and the TPS manufacturer. Calculation of total volume and DVH data was consistent between SWAN and each TPS, with the small discrepancies found tending to increase with decreasing structure size. This was significantly influenced by the TPS model used to derive the data. For target structures covered with relatively uniform dose distributions, there was a significant difference between the minimum dose in each TPS-exported DVH and that calculated independently. (note)

  2. A DVH-guided IMRT optimization algorithm for automatic treatment planning and adaptive radiotherapy replanning

    International Nuclear Information System (INIS)

    Zarepisheh, Masoud; Li, Nan; Long, Troy; Romeijn, H. Edwin; Tian, Zhen; Jia, Xun; Jiang, Steve B.

    2014-01-01

    Purpose: To develop a novel algorithm that incorporates prior treatment knowledge into intensity modulated radiation therapy optimization to facilitate automatic treatment planning and adaptive radiotherapy (ART) replanning. Methods: The algorithm automatically creates a treatment plan guided by the DVH curves of a reference plan that contains information on the clinician-approved dose-volume trade-offs among different targets/organs and among different portions of a DVH curve for an organ. In ART, the reference plan is the initial plan for the same patient, while for automatic treatment planning the reference plan is selected from a library of clinically approved and delivered plans of previously treated patients with similar medical conditions and geometry. The proposed algorithm employs a voxel-based optimization model and navigates the large voxel-based Pareto surface. The voxel weights are iteratively adjusted to approach a plan that is similar to the reference plan in terms of the DVHs. If the reference plan is feasible but not Pareto optimal, the algorithm generates a Pareto optimal plan with the DVHs better than the reference ones. If the reference plan is too restricting for the new geometry, the algorithm generates a Pareto plan with DVHs close to the reference ones. In both cases, the new plans have similar DVH trade-offs as the reference plans. Results: The algorithm was tested using three patient cases and found to be able to automatically adjust the voxel-weighting factors in order to generate a Pareto plan with similar DVH trade-offs as the reference plan. The algorithm has also been implemented on a GPU for high efficiency. Conclusions: A novel prior-knowledge-based optimization algorithm has been developed that automatically adjust the voxel weights and generate a clinical optimal plan at high efficiency. It is found that the new algorithm can significantly improve the plan quality and planning efficiency in ART replanning and automatic treatment

  3. 3D DVH-based metric analysis versus per-beam planar analysis in IMRT pretreatment verification

    International Nuclear Information System (INIS)

    Carrasco, Pablo; Jornet, Núria; Latorre, Artur; Eudaldo, Teresa; Ruiz, Agustí; Ribas, Montserrat

    2012-01-01

    Purpose: To evaluate methods of pretreatment IMRT analysis, using real measurements performed with a commercial 2D detector array, for clinical relevance and accuracy by comparing clinical DVH parameters. Methods: We divided the work into two parts. The first part consisted of six in-phantom tests aimed to study the sensitivity of the different analysis methods. Beam fluences, 3D dose distribution, and DVH of an unaltered original plan were compared to those of the delivered plan, in which an error had been intentionally introduced. The second part consisted of comparing gamma analysis with DVH metrics for 17 patient plans from various sites. Beam fluences were measured with the MapCHECK 2 detector, per-beam planar analysis was performed with the MapCHECK software, and 3D gamma analysis and the DVH evaluation were performed using 3DVH software. Results: In a per-beam gamma analysis some of the tests yielded false positives or false negatives. However, the 3DVH software correctly described the DVH of the plan which included the error. The measured DVH from the plan with controlled error agreed with the planned DVH within 2% dose or 2% volume. We also found that a gamma criterion of 3%/3 mm was too lax to detect some of the forced errors. Global analysis masked some problems, while local analysis magnified irrelevant errors at low doses. Small hotspots were missed for all metrics due to the spatial resolution of the detector panel. DVH analysis for patient plans revealed small differences between treatment plan calculations and 3DVH results, with the exception of very small volume structures such as the eyes and the lenses. Target coverage (D 98 and D 95 ) of the measured plan was systematically lower than that predicted by the treatment planning system, while other DVH characteristics varied depending on the parameter and organ. Conclusions: We found no correlation between the gamma index and the clinical impact of a discrepancy for any of the gamma index evaluation

  4. Significant correlation between rectal DVH and late bleeding in patients treated after radical prostatectomy with conformal or conventional radiotherapy (66.6-70.2 Gy)

    International Nuclear Information System (INIS)

    Cozzarini, Cesare; Fiorino, Claudio; Ceresoli, Giovanni Luca; Cattaneo, Giovanni Mauro; Bolognesi, Angelo; Calandrino, Riccardo; Villa, Eugenio

    2003-01-01

    Purpose: Investigating the correlation between dosimetric/clinical parameters and late rectal bleeding in patients treated with adjuvant or salvage radiotherapy after radical prostatectomy. Methods and Materials: Data of 154 consecutive patients, including three-dimensional treatment planning and dose-volume histograms (DVHs) of the rectum (including filling), were retrospectively analyzed. Twenty-six of 154 patients presenting a (full) rectal volume >100 cc were excluded from the analysis. All patients considered for the analysis (n=128) were treated at a nominal dose equal to 66.6-70.2 Gy (ICRU dose 68-72.5 Gy; median 70 Gy) with conformal (n=76) or conventional (n=52) four-field technique (1.8 Gy/fr). Clinical parameters such as diabetes mellitus, acute rectal bleeding, hypertension, age, and hormonal therapy were considered. Late rectal bleeding was scored using a modified Radiation Therapy Oncology Group scale, and patients experiencing ≥Grade 2 were considered bleeders. Median follow-up was 36 months (range 12-72). Mean and median rectal dose were considered, together with rectal volume and the % fraction of rectum receiving more than 50, 55, 60, and 65 Gy (V50, V55, V60, V65, respectively). Median and quartile values of all parameters were taken as cutoff for statistical analysis. Univariate (log-rank) and multivariate (Cox hazard model) analyses were performed. Results: Fourteen of 128 patients experienced ≥Grade 2 late bleeding (3-year actuarial incidence 10.5%). A significant correlation between a number of cutoff values and late rectal bleeding was found. In particular, a mean dose ≥54 Gy, V50 ≥63%, V55 ≥57%, and V60 ≥50% was highly predictive of late bleeding (p≤0.01). A rectal volume <60 cc and type of treatment (conventional vs. conformal) were also significantly predictive of late bleeding (p=0.05). Concerning clinical variables, acute bleeding (p < 0.001) was significantly related to late bleeding, and a trend was found for

  5. TH-E-BRF-05: Comparison of Survival-Time Prediction Models After Radiotherapy for High-Grade Glioma Patients Based On Clinical and DVH Features

    International Nuclear Information System (INIS)

    Magome, T; Haga, A; Igaki, H; Sekiya, N; Masutani, Y; Sakumi, A; Mukasa, A; Nakagawa, K

    2014-01-01

    Purpose: Although many outcome prediction models based on dose-volume information have been proposed, it is well known that the prognosis may be affected also by multiple clinical factors. The purpose of this study is to predict the survival time after radiotherapy for high-grade glioma patients based on features including clinical and dose-volume histogram (DVH) information. Methods: A total of 35 patients with high-grade glioma (oligodendroglioma: 2, anaplastic astrocytoma: 3, glioblastoma: 30) were selected in this study. All patients were treated with prescribed dose of 30–80 Gy after surgical resection or biopsy from 2006 to 2013 at The University of Tokyo Hospital. All cases were randomly separated into training dataset (30 cases) and test dataset (5 cases). The survival time after radiotherapy was predicted based on a multiple linear regression analysis and artificial neural network (ANN) by using 204 candidate features. The candidate features included the 12 clinical features (tumor location, extent of surgical resection, treatment duration of radiotherapy, etc.), and the 192 DVH features (maximum dose, minimum dose, D95, V60, etc.). The effective features for the prediction were selected according to a step-wise method by using 30 training cases. The prediction accuracy was evaluated by a coefficient of determination (R 2 ) between the predicted and actual survival time for the training and test dataset. Results: In the multiple regression analysis, the value of R 2 between the predicted and actual survival time was 0.460 for the training dataset and 0.375 for the test dataset. On the other hand, in the ANN analysis, the value of R 2 was 0.806 for the training dataset and 0.811 for the test dataset. Conclusion: Although a large number of patients would be needed for more accurate and robust prediction, our preliminary Result showed the potential to predict the outcome in the patients with high-grade glioma. This work was partly supported by the JSPS Core

  6. The dose distribution and DVH change analysis wing to effect of the patient setup error

    International Nuclear Information System (INIS)

    Kim, Kyung Tae; Ju, Sang Gyu; Ahn, Jae Hong; Park, Young Hwan

    2004-01-01

    The setup error due to the patient and the staff from radiation treatment as the reason which is important the treatment record could be decided is a possibility of effect. The SET-UP ERROR of the patient analyzes the effect of dose distribution and DVH from radiation treatment of the patient. This test uses human phantom and when C-T scan doing, It rotated the Left direction of the human phantom and it made SET-UP ERROR, Standard plan and 3 mm, 5 mm, 7 mm, 10 mm, 15 mm, 20 mm with to distinguish, it made the C-T scan error. With the result, The SET-UP ERROR got each C-T image Using RTP equipment It used the plan which is used generally from clinical - Box plan, 3 Dimension plan( identical angle 5beam plan) Also, ( CTV+1cm margin, CTV+0.5cm margin, CTV+0.3,cm margin = PTV) it distinguished the standard plan and each set-up error plan and the plan used a dose distribution and the DVH and it analyzed. The Box 4 the plan and 3 Dimension plan which it bites it got similar an dose distribution and DVH in 3 mm, 5 mm From rotation error and Rectilinear movement (0%-2%). Rotation error and rectilinear error 7 mm, 10 mm, 15 mm, 20 mm appeared effect it will go mad to a enough change in treatment (2%-11%) The diminishes the effect of the SET-UP ERROR must reduce move with tension of the patient Also, we are important accessory development and the supply that it reducing of reproducibility and the move.

  7. SU-F-T-254: Dose Volume Histogram (DVH) Analysis of Breath Hold Vs Free Breathing Techniques for Esophageal Tumors

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    Badkul, R; Doke, K; Pokhrel, D; Aguilera, N; Lominska, C [University of Kansas Medical Center, Kansas City, KS (United States)

    2016-06-15

    Purpose: Lung and heart doses and associated toxicity are of concern in radiotherapy for esophageal cancer. This study evaluates the dosimetry of deep-inspiration-breath-hold (DIBH) technique as compared to freebreathing( FB) using 3D-conformal treatment(3D-CRT) of esophageal cancer. Methods: Eight patients were planned with FB and DIBH CT scans. DIBH scans were acquired using Varian RPM system. FB and DIBH CTs were contoured per RTOG-1010 to create the planning target volume(PTV) as well as organs at risk volumes(OAR). Two sets of gross target volumes(GTV) with 5cm length were contoured for each patient: proximal at the level of the carina and distal at the level of gastroesophageal junction and were enlarged with appropriate margin to generate Clinical Target Volume and PTV. 3D-CRT plans were created on Eclipse planning system for 45Gy to cover 95% of PTV in 25 fractions for both proximal and distal tumors on FB and DIBH scans. For distal tumors celiac nodes were covered electively. DVH parameters for lung and heart OARs were generated and analyzed. Results: All DIBH DVH parameters were normalized to FB plan values. Average of heart-mean and heart-V40 was 0.70 and 0.66 for proximal lesions. For distal lesions ratios were 1.21 and 2.22 respectively. For DIBH total lung volume increased by 2.43 times versus FB scan. Average of lung-mean, V30, V20, V10, V5 are 0.82, 0.92, 0.76, 0.77 and 0.79 for proximal lesions and 1.17,0.66,0.87,0.93 and 1.03 for distal lesions. Heart doses were lower for breath-hold proximal lesions but higher for distal lesions as compared to free-breathing plans. Lung doses were lower for both proximal and distal breath-hold lesions except mean lung dose and V5 for distal lesions. Conclusion: This study showed improvement of OAR doses for esophageal lesions at mid-thoracic level utilizing DIBH vs FB technique but did not show consistent OAR sparing with DIBH for distal lesions.

  8. SU-F-T-254: Dose Volume Histogram (DVH) Analysis of Breath Hold Vs Free Breathing Techniques for Esophageal Tumors

    International Nuclear Information System (INIS)

    Badkul, R; Doke, K; Pokhrel, D; Aguilera, N; Lominska, C

    2016-01-01

    Purpose: Lung and heart doses and associated toxicity are of concern in radiotherapy for esophageal cancer. This study evaluates the dosimetry of deep-inspiration-breath-hold (DIBH) technique as compared to freebreathing( FB) using 3D-conformal treatment(3D-CRT) of esophageal cancer. Methods: Eight patients were planned with FB and DIBH CT scans. DIBH scans were acquired using Varian RPM system. FB and DIBH CTs were contoured per RTOG-1010 to create the planning target volume(PTV) as well as organs at risk volumes(OAR). Two sets of gross target volumes(GTV) with 5cm length were contoured for each patient: proximal at the level of the carina and distal at the level of gastroesophageal junction and were enlarged with appropriate margin to generate Clinical Target Volume and PTV. 3D-CRT plans were created on Eclipse planning system for 45Gy to cover 95% of PTV in 25 fractions for both proximal and distal tumors on FB and DIBH scans. For distal tumors celiac nodes were covered electively. DVH parameters for lung and heart OARs were generated and analyzed. Results: All DIBH DVH parameters were normalized to FB plan values. Average of heart-mean and heart-V40 was 0.70 and 0.66 for proximal lesions. For distal lesions ratios were 1.21 and 2.22 respectively. For DIBH total lung volume increased by 2.43 times versus FB scan. Average of lung-mean, V30, V20, V10, V5 are 0.82, 0.92, 0.76, 0.77 and 0.79 for proximal lesions and 1.17,0.66,0.87,0.93 and 1.03 for distal lesions. Heart doses were lower for breath-hold proximal lesions but higher for distal lesions as compared to free-breathing plans. Lung doses were lower for both proximal and distal breath-hold lesions except mean lung dose and V5 for distal lesions. Conclusion: This study showed improvement of OAR doses for esophageal lesions at mid-thoracic level utilizing DIBH vs FB technique but did not show consistent OAR sparing with DIBH for distal lesions.

  9. SU-E-T-789: Validation of 3DVH Accuracy On Quantifying Delivery Errors Based On Clinical Relevant DVH Metrics

    International Nuclear Information System (INIS)

    Ma, T; Kumaraswamy, L

    2015-01-01

    Purpose: Detection of treatment delivery errors is important in radiation therapy. However, accurate quantification of delivery errors is also of great importance. This study aims to evaluate the 3DVH software’s ability to accurately quantify delivery errors. Methods: Three VMAT plans (prostate, H&N and brain) were randomly chosen for this study. First, we evaluated whether delivery errors could be detected by gamma evaluation. Conventional per-beam IMRT QA was performed with the ArcCHECK diode detector for the original plans and for the following modified plans: (1) induced dose difference error up to ±4.0% and (2) control point (CP) deletion (3 to 10 CPs were deleted) (3) gantry angle shift error (3 degree uniformly shift). 2D and 3D gamma evaluation were performed for all plans through SNC Patient and 3DVH, respectively. Subsequently, we investigated the accuracy of 3DVH analysis for all cases. This part evaluated, using the Eclipse TPS plans as standard, whether 3DVH accurately can model the changes in clinically relevant metrics caused by the delivery errors. Results: 2D evaluation seemed to be more sensitive to delivery errors. The average differences between ECLIPSE predicted and 3DVH results for each pair of specific DVH constraints were within 2% for all three types of error-induced treatment plans, illustrating the fact that 3DVH is fairly accurate in quantifying the delivery errors. Another interesting observation was that even though the gamma pass rates for the error plans are high, the DVHs showed significant differences between original plan and error-induced plans in both Eclipse and 3DVH analysis. Conclusion: The 3DVH software is shown to accurately quantify the error in delivered dose based on clinically relevant DVH metrics, where a conventional gamma based pre-treatment QA might not necessarily detect

  10. Parotid gland tumors: a comparison of postoperative radiotherapy techniques using three dimensional (3-D) dose distributions and dose-volume histograms (DVH)

    International Nuclear Information System (INIS)

    Yaparpalvi, R.; Tyerech, S.K.; Boselli, L.R.; Fontenla, D.P.; Beitler, J.J.; Vikram, B.

    1996-01-01

    Purpose/Objective: To compare different treatment techniques for unilateral treatment of parotid gland tumors. Materials and Methods: Twenty patients previously treated postoperatively for parotid gland tumors were retrospectively reviewed. Average field size was 9 x 11 cm, average separation was 15.5 cm, and the average prescription depth was 4.5 cm. Using 3-D dose distributions, tissue inhomogeneity corrections, scatter integration (for photons) and pencil beam (for electrons) algorithms and DVH, nine treatment techniques were compared using a representative patient. The treatment techniques investigated were: [1] unilateral 6 MV photons. [2] unilateral 12 MeV electrons. [3] unilateral 16 MeV electrons. [4] a ipsilateral wedge pair technique using 6 MV photons and a 45-degree wedge. [5] a 3-field AP (wedged), PA (wedged) and lateral portal technique using 6 MV photons. [6] a mixed beam technique using 6 MV photons and 12 MeV electrons (1:4 weighting). [7] a mixed beam technique using 6 MV photons and 16 MeV electrons (1:4 weighting). [8] a mixed beam technique using 18 MV photons and 20 MeV electrons (2:3 weighting). [9] a mixed beam technique using 18 MV photons and 20 MeV electrons (1:1 weighting). Results: Using dose-volume histograms to evaluate the dose to the contralateral parotid gland, the percentage of contralateral parotid volume receiving ≥30% of the prescribed dose was 100% for techniques [1], [8] and [9], and <5% for techniques [2] through [7]. Evaluating the 'hottest' 5 cc of the ipsilateral mandible and temporal lobes, the hot spots were: 152% and 150% for technique [2], 132% and 130% for technique [6]. Comparing the exit doses, techniques [1] and [8] contributed to ≥50% of the prescribed dose to the contralateral mandible and the temporal lobes. Only techniques [2] and [6] kept the highest point doses to both the brain stem and the spinal cord below 50% of the prescribed dose. Conclusion: The single photon lateral field [1] and the mixed

  11. Evaluation of DVH-based treatment plan verification in addition to gamma passing rates for head and neck IMRT

    International Nuclear Information System (INIS)

    Visser, Ruurd; Wauben, David J.L.; Groot, Martijn de; Steenbakkers, Roel J.H.M.; Bijl, Henk P.; Godart, Jeremy; Veld, Aart A. van’t; Langendijk, Johannes A.; Korevaar, Erik W.

    2014-01-01

    Background and purpose: Treatment plan verification of intensity modulated radiotherapy (IMRT) is generally performed with the gamma index (GI) evaluation method, which is difficult to extrapolate to clinical implications. Incorporating Dose Volume Histogram (DVH) information can compensate for this. The aim of this study was to evaluate DVH-based treatment plan verification in addition to the GI evaluation method for head and neck IMRT. Materials and methods: Dose verifications of 700 subsequent head and neck cancer IMRT treatment plans were categorised according to gamma and DVH-based action levels. Fractionation dependent absolute dose limits were chosen. The results of the gamma- and DVH-based evaluations were compared to the decision of the medical physicist and/or radiation oncologist for plan acceptance. Results: Nearly all treatment plans (99.7%) were accepted for treatment according to the GI evaluation combined with DVH-based verification. Two treatment plans were re-planned according to DVH-based verification, which would have been accepted using the evaluation alone. DVH-based verification increased insight into dose delivery to patient specific structures increasing confidence that the treatment plans were clinically acceptable. Moreover, DVH-based action levels clearly distinguished the role of the medical physicist and radiation oncologist within the Quality Assurance (QA) procedure. Conclusions: DVH-based treatment plan verification complements the GI evaluation method improving head and neck IMRT-QA

  12. SU-E-T-525: Dose Volume Histograms (DVH) Analysis and Comparison with ICRU Point Doses in MRI Guided HDR Brachytherapy for Cervical Cancer

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    Badkul, R; McClinton, C; Kumar, P; Mitchell, M [University of Kansas Medical Center, Kansas City, KS (United States)

    2014-06-01

    Purpose: Brachytherapy plays a crucial role in management of cervix cancer. MRI compatible applicators have made it possible to accurately delineate gross-target-volume(GTV) and organs-at-risk(OAR) volumes, as well as directly plan, optimize and adapt dose-distribution for each insertion. We sought to compare DVH of tumor-coverage and OARs to traditional Point-A, ICRU-38 bladder and rectum point-doses for four different planning-techniques. Methods: MRI based 3D-planning was performed on Nucletron-Oncentra-TPS for 3 selected patients with varying tumor-sizes and anatomy. GTV,high-risk-clinical-target-volume(HR-CTV), intermediate-risk-clinical-target-volume(IR-CTV) and OARs: rectum, bladder, sigmoid-colon, vaginal-mucosa were delineated. Three conventionally used techniques: mg-Radium-equivalent(RaEq),equal-dwell-weights(EDW), Medical-College-of-Wisconsin proposed points-optimization (MCWO) and a manual-graphical-optimization(MGO) volume-coverage based technique were applied for each patient. Prescription was 6Gy delivered to point-A in Conventional techniques (RaEq, EDW, MCWO). For MGO, goal was to achieve 90%-coverage (D90) to HR-CTV with prescription-dose. ICRU point doses for rectum and bladder, point-A doses, DVH-doses for HR-CTV-D90,0.1cc-volume(D0.1),1ccvolume( D1),2cc-volume(D2) were collected for all plans and analyzed . Results: Mean D90 for HR-CTV normalized to MGO were 0.89,0.84,0.9,1.0 for EDW, RaEq, MCWO, MGO respectively. Mean point-A doses were 21.7% higher for MGO. Conventional techniques with Point-A prescriptions under covered HR-CTV-D90 by average of 12% as compared to MGO. Rectum, bladder and sigmoid doses were highest in MGO-plans for ICRU points as well as D0.1,D1 and D2 doses. Among conventional-techniques, rectum and bladder ICRU and DVH doses(0.1,1,2cc) were not significantly different (within 7%).Rectum D0.1 provided good estimation of ICRU-rectum-point doses (within 3.9%),rectum D0.1 were higher from 0.8 to 3.9% while bladder D0

  13. Results and DVH analysis of late rectal bleeding in patients treated with 3D-CRT or IMRT for localized prostate cancer

    International Nuclear Information System (INIS)

    Someya, Masanori; Hori, Masakazu; Tateoka, Kunihiko; Nakata, Kensei; Saito, Masato; Hirokawa, Naoki; Sakata, Koh-ichi; Takagi, Masaru; Hareyama, Masato

    2015-01-01

    In patients undergoing radiotherapy for localized prostate cancer, dose-volume histograms and clinical variables were examined to search for correlations between radiation treatment planning parameters and late rectal bleeding. We analyzed 129 patients with localized prostate cancer who were managed from 2002 to 2010 at our institution. They were treated with 3D conformal radiation therapy (3D-CRT, 70 Gy/35 fractions, 55 patients) or intensity-modulated radiation therapy (IMRT, 76 Gy/38 fractions, 74 patients). All radiation treatment plans were retrospectively reconstructed, dose-volume histograms of the rectum were generated, and the doses delivered to the rectum were calculated. Time to rectal bleeding ranged from 9 - 53 months, with a median of 18.7 months. Of the 129 patients, 33 patients had Grade 1 bleeding and were treated with steroid suppositories, while 25 patients with Grade 2 bleeding received argon plasma laser coagulation therapy (APC). Three patients with Grade 3 bleeding required both APC and blood transfusion. The 5-year incidence rate of Grade 2 or 3 rectal bleeding was 21.8% for the 3D-CRT group and 21.6% for the IMRT group. Univariate analysis showed significant differences in the average values from V65 to V10 between Grades 0 - 1 and Grades 2 - 3. Multivariate analysis demonstrated that patients with V65 ≥ 17% had a significantly increased risk (P = 0.032) of Grade 2 or 3 rectal bleeding. Of the 28 patients of Grade 2 or 3 rectal bleeding, 17 patients (60.7%) were cured by a single session of APC, while the other 11 patients required two sessions. Thus, none of the patients had any further rectal bleeding after the second APC session. (author)

  14. Generation of benchmark DVH's for normal tissues in IMRT for base of tongue and tonsil cancer patients

    International Nuclear Information System (INIS)

    Rana, B.S.; Arun Singh, O.; Goswami, P.; Bhardwaj, A.; Santam; Susmita, Goshal; Sharma, S.C.

    2007-01-01

    IMRT is the treatment of choice for treatment of prostate and H and N cancer treatment but it take quality of time to generate an optimal treatment plan and Dose Volume Histogram (DVH) varies significantly from one plan to other patient plan which is difficult to compare. Here the authors propose to generate bench mark DVH's for normal tissues for Base of tongue (BOT) and Tonsil cancer treatment to bring consistency in selection of plans and reduce the overall time of planning and comparison b/n different plan will be simpler and easier. Here the authors propose to generate benchmark DVH for spinal cord, larynx, pharynx, parotid and brain stem for BOT and tonsil patients treated with Intensity modulated radiotherapy in Postgraduate Institute of Medical Education and Research. And to see whether Benchmark DVH can be effectively used in IMRT for BOT and Ca Tonsil

  15. Biological-effective versus conventional dose volume histograms correlated with late genitourinary and gastrointestinal toxicity after external beam radiotherapy for prostate cancer: a matched pair analysis

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    Roeske John C

    2003-05-01

    Full Text Available Abstract Background To determine whether the dose-volume histograms (DVH's for the rectum and bladder constructed using biological-effective dose (BED-DVH's better correlate with late gastrointestinal (GI and genitourinary (GU toxicity after treatment with external beam radiotherapy for prostate cancer than conventional DVH's (C-DVH's. Methods The charts of 190 patients treated with external beam radiotherapy with a minimum follow-up of 2 years were reviewed. Six patients (3.2% were found to have RTOG grade 3 GI toxicity, and similarly 6 patients (3.2% were found to have RTOG grade 3 GU toxicity. Average late C-DVH's and BED-DVH's of the bladder and rectum were computed for these patients as well as for matched-pair control patients. For each matched pair the following measures of normalized difference in the DVH's were computed: (a δAUC = (Area Under Curve [AUC] in grade 3 patient – AUC in grade 0 patient/(AUC in grade 0 patient and (b δV60 = (Percent volume receiving = 60 Gy [V60] in grade 3 patient – V60 in grade 0 patient/(V60 in grade 0 patient. Results As expected, the grade 3 curve is to the right of and above the grade 0 curve for all four sets of average DVH's – suggesting that both the C-DVH and the BED-DVH can be used for predicting late toxicity. δAUC was higher for the BED-DVH's than for the C-DVH's – 0.27 vs 0.23 (p = 0.036 for the rectum and 0.24 vs 0.20 (p = 0.065 for the bladder. δV60 was also higher for the BED-DVH's than for the C-DVH's – 2.73 vs 1.49 for the rectum (p = 0.021 and 1.64 vs 0.71 (p = 0.021 for the bladder. Conclusions When considering well-established dosimetric endpoints used in evaluating treatment plans, BED-DVH's for the rectum and bladder correlate better with late toxicity than C-DVH's and should be considered when attempting to minimize late GI and GU toxicity after external beam radiotherapy for prostate cancer.

  16. Poster - Thur Eve - 54: A software solution for ongoing DVH quality assurance in radiation therapy.

    Science.gov (United States)

    Annis, S-L; Zeng, G; Wu, X; Macpherson, M

    2012-07-01

    A program has been developed in MATLAB for use in quality assurance of treatment planning of radiation therapy. It analyzes patient DVH files and compiles dose volume data for review, trending, comparison and analysis. Patient DVH files are exported from the Eclipse treatment planning system and saved according to treatment sites and date. Currently analysis is available for 4 treatment sites; Prostate, Prostate Bed, Lung, and Upper GI, with two functions for data report and analysis: patient-specific and organ-specific. The patient-specific function loads one patient DVH file and reports the user-specified dose volume data of organs and targets. These data can be compiled to an external file for a third party analysis. The organ-specific function extracts a requested dose volume of an organ from the DVH files of a patient group and reports the statistics over this population. A graphical user interface is utilized to select clinical sites, function and structures, and input user's requests. We have implemented this program in planning quality assurance at our center. The program has tracked the dosimetric improvement in GU sites after VMAT was implemented clinically. It has generated dose volume statistics for different groups of patients associated with technique or time range. This program allows reporting and statistical analysis of DVH files. It is an efficient tool for the planning quality control in radiation therapy. © 2012 American Association of Physicists in Medicine.

  17. Assessment of PlanIQ Feasibility DVH for head and neck treatment planning.

    Science.gov (United States)

    Fried, David V; Chera, Bhishamjit S; Das, Shiva K

    2017-09-01

    Designing a radiation plan that optimally delivers both target coverage and normal tissue sparing is challenging. There are limited tools to determine what is dosimetrically achievable and frequently the experience of the planner/physician is relied upon to make these determinations. PlanIQ software provides a tool that uses target and organ at risk (OAR) geometry to indicate the difficulty of achieving different points for organ dose-volume histograms (DVH). We hypothesized that PlanIQ Feasibility DVH may aid planners in reducing dose to OARs. Clinically delivered head and neck treatments (clinical plan) were re-planned (re-plan) putting high emphasis on maximally sparing the contralateral parotid gland, contralateral submandibular gland, and larynx while maintaining routine clinical dosimetric objectives. The planner was blinded to the results of the clinically delivered plan as well as the Feasibility DVHs from PlanIQ. The re-plan treatments were designed using 3-arc VMAT in Raystation (RaySearch Laboratories, Sweden). The planner was then given the results from the PlanIQ Feasibility DVH analysis and developed an additional plan incorporating this information using 4-arc VMAT (IQ plan). The DVHs across the three treatment plans were compared with what was deemed "impossible" by PlanIQ's Feasibility DVH (Impossible DVH). The impossible DVH (red) is defined as the DVH generated using the minimal dose that any voxel outside the targets must receive given 100% target coverage. The re-plans performed blinded to PlanIQ Feasibilty DVH achieved superior sparing of aforementioned OARs compared to the clinically delivered plans and resulted in discrepancies from the impossible DVHs by an average of 200-700 cGy. Using the PlanIQ Feasibility DVH led to additionalOAR sparing compared to both the re-plans and clinical plans and reduced the discrepancies from the impossible DVHs to an average of approximately 100 cGy. The dose reduction from clinical to re-plan and re-plan to

  18. New algorithm for risk analysis in radiotherapy

    International Nuclear Information System (INIS)

    Torres, Antonio; Montes de Oca, Joe

    2015-01-01

    Risk analyses applied to radiotherapy treatments have become an undeniable necessity, considering the dangers generated by the combination of using powerful radiation fields on patients and the occurrence of human errors and equipment failures during these treatments. The technique par excellence to execute these analyses has been the risk matrix. This paper presents the development of a new algorithm to execute the task with wide graphic and analytic potentialities, thus transforming it into a very useful option for risk monitoring and the optimization of quality assurance. The system SECURE- MR, which is the basic software of this algorithm, has been successfully used in risk analysis regarding different kinds of radiotherapies. Compared to previous methods, It offers new possibilities of analysis considering risk controlling factors as the robustness of reducers of initiators frequency and its consequences. Their analytic capacities and graphs allow novel developments to classify risk contributing factors, to represent information processes as well as accidental sequences. The paper shows the application of the proposed system to a generic process of radiotherapy treatment using a lineal accelerator. (author)

  19. Critical feature analysis of a radiotherapy machine

    International Nuclear Information System (INIS)

    Rae, Andrew; Jackson, Daniel; Ramanan, Prasad; Flanz, Jay; Leyman, Didier

    2005-01-01

    The software implementation of the emergency shutdown feature in a major radiotherapy system was analyzed, using a directed form of code review based on module dependences. Dependences between modules are labelled by particular assumptions; this allows one to trace through the code, and identify those fragments responsible for critical features. An 'assumption tree' is constructed in parallel, showing the assumptions which each module makes about others. The root of the assumption tree is the critical feature of interest, and its leaves represent assumptions which, if not valid, might cause the critical feature to fail. The analysis revealed some unexpected assumptions that motivated improvements to the code

  20. Radiotherapy

    International Nuclear Information System (INIS)

    Prosnitz, L.R.; Kapp, D.S.; Weissberg, J.B.

    1983-01-01

    This review highlights developments over the past decade in radiotherapy and attempts to summarize the state of the art in the management of the major diseases in which radiotherapy has a meaningful role. The equipment, radiobiology of radiotherapy and carcinoma of the lung, breast and intestines are highlighted

  1. Methods, software and datasets to verify DVH calculations against analytical values: Twenty years late(r)

    Energy Technology Data Exchange (ETDEWEB)

    Nelms, Benjamin [Canis Lupus LLC, Merrimac, Wisconsin 53561 (United States); Stambaugh, Cassandra [Department of Physics, University of South Florida, Tampa, Florida 33612 (United States); Hunt, Dylan; Tonner, Brian; Zhang, Geoffrey; Feygelman, Vladimir, E-mail: vladimir.feygelman@moffitt.org [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, Florida 33612 (United States)

    2015-08-15

    Purpose: The authors designed data, methods, and metrics that can serve as a standard, independent of any software package, to evaluate dose-volume histogram (DVH) calculation accuracy and detect limitations. The authors use simple geometrical objects at different orientations combined with dose grids of varying spatial resolution with linear 1D dose gradients; when combined, ground truth DVH curves can be calculated analytically in closed form to serve as the absolute standards. Methods: DICOM RT structure sets containing a small sphere, cylinder, and cone were created programmatically with axial plane spacing varying from 0.2 to 3 mm. Cylinders and cones were modeled in two different orientations with respect to the IEC 1217 Y axis. The contours were designed to stringently but methodically test voxelation methods required for DVH. Synthetic RT dose files were generated with 1D linear dose gradient and with grid resolution varying from 0.4 to 3 mm. Two commercial DVH algorithms—PINNACLE (Philips Radiation Oncology Systems) and PlanIQ (Sun Nuclear Corp.)—were tested against analytical values using custom, noncommercial analysis software. In Test 1, axial contour spacing was constant at 0.2 mm while dose grid resolution varied. In Tests 2 and 3, the dose grid resolution was matched to varying subsampled axial contours with spacing of 1, 2, and 3 mm, and difference analysis and metrics were employed: (1) histograms of the accuracy of various DVH parameters (total volume, D{sub max}, D{sub min}, and doses to % volume: D99, D95, D5, D1, D0.03 cm{sup 3}) and (2) volume errors extracted along the DVH curves were generated and summarized in tabular and graphical forms. Results: In Test 1, PINNACLE produced 52 deviations (15%) while PlanIQ produced 5 (1.5%). In Test 2, PINNACLE and PlanIQ differed from analytical by >3% in 93 (36%) and 18 (7%) times, respectively. Excluding D{sub min} and D{sub max} as least clinically relevant would result in 32 (15%) vs 5 (2

  2. Methods, software and datasets to verify DVH calculations against analytical values: Twenty years late(r).

    Science.gov (United States)

    Nelms, Benjamin; Stambaugh, Cassandra; Hunt, Dylan; Tonner, Brian; Zhang, Geoffrey; Feygelman, Vladimir

    2015-08-01

    The authors designed data, methods, and metrics that can serve as a standard, independent of any software package, to evaluate dose-volume histogram (DVH) calculation accuracy and detect limitations. The authors use simple geometrical objects at different orientations combined with dose grids of varying spatial resolution with linear 1D dose gradients; when combined, ground truth DVH curves can be calculated analytically in closed form to serve as the absolute standards. dicom RT structure sets containing a small sphere, cylinder, and cone were created programmatically with axial plane spacing varying from 0.2 to 3 mm. Cylinders and cones were modeled in two different orientations with respect to the IEC 1217 Y axis. The contours were designed to stringently but methodically test voxelation methods required for DVH. Synthetic RT dose files were generated with 1D linear dose gradient and with grid resolution varying from 0.4 to 3 mm. Two commercial DVH algorithms-pinnacle (Philips Radiation Oncology Systems) and PlanIQ (Sun Nuclear Corp.)-were tested against analytical values using custom, noncommercial analysis software. In Test 1, axial contour spacing was constant at 0.2 mm while dose grid resolution varied. In Tests 2 and 3, the dose grid resolution was matched to varying subsampled axial contours with spacing of 1, 2, and 3 mm, and difference analysis and metrics were employed: (1) histograms of the accuracy of various DVH parameters (total volume, Dmax, Dmin, and doses to % volume: D99, D95, D5, D1, D0.03 cm(3)) and (2) volume errors extracted along the DVH curves were generated and summarized in tabular and graphical forms. In Test 1, pinnacle produced 52 deviations (15%) while PlanIQ produced 5 (1.5%). In Test 2, pinnacle and PlanIQ differed from analytical by >3% in 93 (36%) and 18 (7%) times, respectively. Excluding Dmin and Dmax as least clinically relevant would result in 32 (15%) vs 5 (2%) scored deviations for pinnacle vs PlanIQ in Test 1, while Test 2

  3. Treatment plan evaluation using dose-volume histogram (DVH) and spatial dose-volume histogram (zDVH)

    International Nuclear Information System (INIS)

    Cheng, C.-W.; Das, Indra J.

    1999-01-01

    Objective: The dose-volume histogram (DVH) has been accepted as a tool for treatment-plan evaluation. However, DVH lacks spatial information. A new concept, the z-dependent dose-volume histogram (zDVH), is presented as a supplement to the DVH in three-dimensional (3D) treatment planning to provide the spatial variation, as well as the size and magnitude of the different dose regions within a region of interest. Materials and Methods: Three-dimensional dose calculations were carried out with various plans for three disease sites: lung, breast, and prostate. DVHs were calculated for the entire volume. A zDVH is defined as a differential dose-volume histogram with respect to a computed tomographic (CT) slice position. In this study, zDVHs were calculated for each CT slice in the treatment field. DVHs and zDVHs were compared. Results: In the irradiation of lung, DVH calculation indicated that the treatment plan satisfied the dose-volume constraint placed on the lung and zDVH of the lung revealed that a sizable fraction of the lung centered about the central axis (CAX) received a significant dose, a situation that warranted a modification of the treatment plan due to the removal of one lung. In the irradiation of breast with tangential fields, the DVH showed that about 7% of the breast volume received at least 110% of the prescribed dose (PD) and about 11% of the breast received less than 98% PD. However, the zDVHs of the breast volume in each of seven planes showed the existence of high-dose regions of 34% and 15%, respectively, of the volume in the two caudal-most planes and cold spots of about 40% in the two cephalic planes. In the treatment planning of prostate, DVHs showed that about 15% of the bladder and 40% of the rectum received 102% PD, whereas about 30% of the bladder and 50% of the rectum received the full dose. Taking into account the hollow structure of both the bladder and the rectum, the dose-surface histograms (DSH) showed larger hot-spot volume, about

  4. Radiotherapy

    Directory of Open Access Journals (Sweden)

    Rema Jyothirmayi

    1999-01-01

    Full Text Available Purpose. Conservative treatment in the form of limited surgery and post-operative radiotherapy is controversial in hand and foot sarcomas, both due to poor radiation tolerance of the palm and sole, and due to technical difficulties in achieving adequate margins.This paper describes the local control and survival of 41 patients with soft tissue sarcoma of the hand or foot treated with conservative surgery and radiotherapy. The acute and late toxicity of megavoltage radiotherapy to the hand and foot are described. The technical issues and details of treatment delivery are discussed. The factors influencing local control after radiotherapy are analysed.

  5. Radiotherapy

    International Nuclear Information System (INIS)

    Zedgenidze, G.A.; Kulikov, V.A.; Mardynskij, Yu.S.

    1984-01-01

    The technique for roentgenotopometric and medicamentous preparation of patients for radiotherapy has been reported in detail. The features of planning and performing of remote, intracavitary and combined therapy in urinary bladder cancer are considered. The more effective methods of radiotherapy have been proposed taking into account own experience as well as literature data. The comparative evaluation of treatment results and prognosis are given. Radiation pathomorphism of tumors and tissues of urinary bladder is considered in detail. The problems of diagnosis, prophylaxis and treatment of complications following radiodiagnosis and radiotherapy in patients with urinary bladder cancer are illustrated widely

  6. MO-G-304-02: Knowledge Based DVH Prediction Using a Geometric Dose Transform

    International Nuclear Information System (INIS)

    Staub, D; Wang, J; Jiang, S

    2015-01-01

    Purpose: To demonstrate a novel method for predicting patient dose-volume histograms (DVHs) using a prior database of optimized radiotherapy treatment plans. Such predicted DVHs could be useful for automating treatment planning. Methods: Our initial demonstration utilized a database of 100 prostate intensity-modulated radiotherapy (IMRT) data-sets. Each data-set contained a CT image with contours of the planning target volume (PTV), rectum, and bladder, the parameters of a clinically approved IMRT plan, and a corresponding simulated dose distribution. We applied a novel geometric transformation to remove the influence of the PTV size, shape, and location on the dose distribution. We termed the transformed distribution the geometrically normalized dose distribution (GNDD). This normalization transform was applied to 80 data-sets randomly selected from the database, and a population GNDD was computed as the average. Next, the population GNDD was mapped onto each of the remaining 20 patient datasets using the reverse of the geometric normalization transform, and predicted DVHs were calculated from the reverse transformed dose distributions (GNDD-DVHs). In addition, a state of the art machine learning based method from the literature was tested for comparison. Results: DVH prediction accuracy was quantified by calculating the relative root mean squared error (rRMSE) on predicted DVHs for the 20 test patients using their known DVHs. For bladder, rectum, and PTV average rRMSEs for the GNDD method were 9.7 ± 4.2%, 13.9 ± 6.0%, and 2.3 ± 0.5% respectively. Prediction results using GNDD were roughly equivalent to that from the machine learning method. Conclusion: We developed a new method for predicting DVH curves from a database of prior patient plans. We demonstrated that our simple approach achieves accuracy comparable to a method using a complicated machine learning based approach

  7. Analysis of dose volume histogram parameters to estimate late bladder and rectum complications after high-dose (70-78 Gy) conformal radiotherapy for prostate cancer

    International Nuclear Information System (INIS)

    Boersma, L.J.; Brink, M. van den; Bruce, A.; Gras, L.; Velde, A. te; Lebesque, J.V.

    1997-01-01

    Purpose: To investigate whether Dose Volume Histogram (DVH) parameters can be used to identify risk groups for developing late gastrointestinal (GI) and genitourinary (GU) complications after conformal radiotherapy for prostate cancer, and to examine the effect of using different morbidity scoring systems on the results of these analyses. Materials and Methods: DVH parameters were analyzed for 130 patients with localized prostate cancer, treated with conformal radiotherapy in a dose-escalating protocol (70-78 Gy, 2 Gy per fraction). The incidence of late (> 6 months) GI and GU complications was scored based on questionnaires and classified using the RTOG/EORTC and the SOMA/LENT scoring system. Moreover, patients were classified as being a rectal bleeder or no rectal bleeder and a distinction was made between non-severe and severe (requiring one or more laser treatments) rectal bleeding. The median follow-up time was 22 months. It was investigated whether the relative and absolute rectal wall volumes, irradiated to various dose levels (≥ 60 Gy, ≥ 65 Gy, ≥ 70 Gy and ≥ 75 Gy) were correlated with the observed actuarial incidences of GI complications. First, the analysis was performed using volume as a continuous variable. Subsequently, for each dose level in the DVH the rectal wall volumes were dichotomized using different volumes as cut-off levels. Twenty cut-off levels were tested on their ability to discriminate between high and low risk for developing GI complications (Fig.). The relationship between bladder wall volumes irradiated to various dose levels and observed actuarial GU complications was investigated using the absolute bladder wall volumes, measured as a continuous variable. For both GI and GU complications, the role of the prescribed radiation dose and the maximum radiation dose in the rectal and bladder wall was analyzed as well. Results: None of the DVH parameters of the rectal wall was significantly correlated with the actuarial incidences of

  8. Use of the 3DVH Software as a complementary method of IMRT pretreatment evaluation; Utilizacao do Software 3DVH como metodo complementar de avaliacao de pre-tratamento de IMRT

    Energy Technology Data Exchange (ETDEWEB)

    Lyra, Jesse G.P.; Bruning, Fabio F.; Funchal, Melissa; Toledo, Hugo V.; Bornatto, Pricila; Fernandes, Tatiane C.O., E-mail: jesse_lyra@hotmail.com [Hospital Erasto Gaertner / Liga Paranaense de Combate ao Cancer (LPCC), Departamento de Radioterapia, Curitiba, PR (Brazil)

    2013-04-15

    The aim of this study is to compare the method of treatment planning evaluation for IMRT using the gamma index to the method of the 3DVH Software. The 3DVH Software was used with the MapCheck2 detector 2D array under a 6MV x-ray beam of linear accelerator equipped with 120 leafs MLC. Nine treatment plans of prostate patients chose randomly and fully anonimatize were performed in the Eclipse planning system, using the AAA calculation algorithm in IMRT sliding window technique. These plans were approved and treated according to the gamma analysis criteria of the institution. The comparisons were made in absolute dose and normalized at maximum dose for each field and then with the 3DVH Software the Dmax, Dmean, D15%, D25%, D35% and D50% parameters for the bladder and rectum, Dmean for the bulb, Dmax for the femur and D95% for the PTV were evaluated. In the planar analysis by field, the plans studied had a minimum of 97.5% approval. The PTV-related differences have relative variation from 1.3 to 2.2%, that is, greater coverage than expected for this structure. For the organs at risk, the relative differences observed were between -5.3 to 25.8%, which could result in a non-approved plan if these variations are close to the clinical tolerances of the OAR. The results show that even a plan compatible with greater than or equal to 95% of the points, the gamma analysis does not give enough information if this plan can or cannot be approved for treatment and that there is a need for more detailed verification of the plan which considers not only the planar evaluation, but also the evaluation of the DVH measured, and the 3DVH Software proved be adequate for this analysis. (author)

  9. Radiotherapy

    International Nuclear Information System (INIS)

    Wannenmacher, M.; Debus, J.; Wenz, F.

    2006-01-01

    The book is focussed on the actual knowledge on the clinical radiotherapy and radio-oncology. Besides fundamental and general contributions specific organ systems are treated in detail. The book contains the following contributions: Basic principles, radiobiological fundamentals, physical background, radiation pathology, basics and technique of brachytherapy, methodology and technique of the stereotactic radiosurgery, whole-body irradiation, operative radiotherapy, hadron therapy, hpyerthermia, combined radio-chemo-therapy, biometric clinical studies, intensity modulated radiotherapy, side effects, oncological diagnostics; central nervous system and sense organs, head-neck carcinomas, breast cancer, thorax organs, esophagus carcinoma, stomach carcinoma, pancreas carcinoma, heptabiliary cancer and liver metastases, rectal carcinomas, kidney and urinary tract, prostate carcinoma, testicular carcinoma, female pelvis, lymphatic system carcinomas, soft tissue carcinoma, skin cancer, bone metastases, pediatric tumors, nonmalignant diseases, emergency in radio-oncology, supporting therapy, palliative therapy

  10. Radiotherapy.

    Science.gov (United States)

    Krause, Sonja; Debus, Jürgen; Neuhof, Dirk

    2011-01-01

    Solitary plasmocytoma occurring in bone (solitary plasmocytoma of the bone, SBP) or in soft tissue (extramedullary plasmocytoma, EP) can be treated effectively and with little toxicity by local radiotherapy. Ten-year local control rates of up to 90% can be achieved. Patients with multiple myeloma often suffer from symptoms such as pain or neurological impairments that are amenable to palliative radiotherapy. In a palliative setting, short treatment schedules and lower radiation doses are used to reduce toxicity and duration of hospitalization. In future, low-dose total body irradiation (TBI) may play a role in a potentially curative regimen with nonmyeloablative conditioning followed by allogenic peripheral blood stem cell transplantation.

  11. Analysis of error patterns in clinical radiotherapy

    International Nuclear Information System (INIS)

    Macklis, Roger; Meier, Tim; Barrett, Patricia; Weinhous, Martin

    1996-01-01

    Purpose: Until very recently, prescription errors and adverse treatment events have rarely been studied or reported systematically in oncology. We wished to understand the spectrum and severity of radiotherapy errors that take place on a day-to-day basis in a high-volume academic practice and to understand the resource needs and quality assurance challenges placed on a department by rapid upswings in contract-based clinical volumes requiring additional operating hours, procedures, and personnel. The goal was to define clinical benchmarks for operating safety and to detect error-prone treatment processes that might function as 'early warning' signs. Methods: A multi-tiered prospective and retrospective system for clinical error detection and classification was developed, with formal analysis of the antecedents and consequences of all deviations from prescribed treatment delivery, no matter how trivial. A department-wide record-and-verify system was operational during this period and was used as one method of treatment verification and error detection. Brachytherapy discrepancies were analyzed separately. Results: During the analysis year, over 2000 patients were treated with over 93,000 individual fields. A total of 59 errors affecting a total of 170 individual treated fields were reported or detected during this period. After review, all of these errors were classified as Level 1 (minor discrepancy with essentially no potential for negative clinical implications). This total treatment delivery error rate (170/93, 332 or 0.18%) is significantly better than corresponding error rates reported for other hospital and oncology treatment services, perhaps reflecting the relatively sophisticated error avoidance and detection procedures used in modern clinical radiation oncology. Error rates were independent of linac model and manufacturer, time of day (normal operating hours versus late evening or early morning) or clinical machine volumes. There was some relationship to

  12. Radiotherapy

    International Nuclear Information System (INIS)

    Pistenma, D.A.

    1980-01-01

    The need for radiotherapy research is exemplified by the 100,000 cancer patients who will fail treatment locally and/or regionally annually for the next several years but who would benefit from better local treatment modalities. Theoretically, all of the areas of investigation discussed in this projection paper have the potential to significantly improve local-regional treatment of cancer by radiotherapy alone or in combination with other modalities. In many of the areas of investigation discussed in this paper encouraging results have been obtained in cellular and animal tumor studies and in limited studies in humans as well. In the not too distant future the number of patients who would benefit from better local control may increase by tens of thousands if developments in chemotherapy and/or immunotherapy provide a means to eradicate disseminated microscopic foci of cancer. Thus the efforts to improve local-regional control take on even greater significance

  13. Dosimetric predictors of diarrhea during radiotherapy for prostate cancer

    International Nuclear Information System (INIS)

    Sanguineti, Giuseppe; Endres, Eugene J.; Parker, Brent C.; Sormani, Maria Pia

    2009-01-01

    Purpose: to investigate dosimetric predictors of diarrhea during radiotherapy (RT) for prostate cancer. Patients and methods: all patients who underwent external-beam radiotherapy as part of treatment for localized prostate cancer at the University of Texas Medical Branch, Galveston, TX, USA, from May 2002 to November 2006 were extracted from the own database. From the cumulative dose-volume histogram (DVH), the absolute volumes (V-value) of intestinal cavity (IC) receiving 15, 30, and 45 Gy were extracted for each patient. Acute gastrointestinal toxicity was prospectively scored at each weekly treatment visit according to CTC (common toxicity criteria) v2.0. The endpoint was the development of peak grade ≥ 2 diarrhea during RT. Various patient, tumor, and treatment characteristics were evaluated using logistic regression. Results: 149 patients were included in the analysis, 112 (75.2%) treated with whole-pelvis intensity-modulated radiotherapy (WP-IMRT) and 37 (24.8%) with prostate-only RT, including or not including, the seminal vesicles (PORT ± SV). 45 patients (30.2%) developed peak grade ≥ 2 diarrhea during treatment. At univariate analysis, IC-V 15 and IC-V 30 , but not IC-V 45 , were correlated to the endpoint; at multivariate analysis, only IC-V 15 (p = 0.047) along with peak acute proctitis (p = 0.041) was independently correlated with the endpoint. Conclusion: these data provide a novel and prostate treatment-specific ''upper limit'' DVH for IC. (orig.)

  14. Deformable image registration for image guided prostate radiotherapy

    International Nuclear Information System (INIS)

    Cassetta, Roberto; Riboldi, Marco; Baroni, Guido; Leandro, Kleber; Novaes, Paulo Eduardo; Goncalves, Vinicius; Sakuraba, Roberto; Fattori, Giovanni

    2016-01-01

    In this study, we present a CT to CBCT deformable registration method based on the ITK library. An algorithm was developed in order to explore the soft tissue information of the CT-CBCT images to perform deformable image registration (DIR), making efforts to overcome the poor signal-to-noise ratio and HU calibration issues that limits CBCT use for treatment planning purposes. Warped CT images and contours were generated and their impact in adaptive radiotherapy was evaluated by DVH analysis for photon and proton treatments. Considerable discrepancies, related to the treatment planning dose distribution, might be found due to changes in patient’s anatomy. (author)

  15. Characterisation of radiotherapy planning volumes using textural analysis

    Energy Technology Data Exchange (ETDEWEB)

    Nailon, William H.; Redpath, Anthony T.; McLaren, Duncan B. (Dept. of Oncology Physics, Edinburgh Cancer Centre, Western General Hospital, Edinburgh (United Kingdom))

    2008-08-15

    Computer-based artificial intelligence methods for classification and delineation of the gross tumour volume (GTV) on computerised tomography (CT) and magnetic resonance (MR) images do not, at present, provide the accuracy required for radiotherapy applications. This paper describes an image analysis method for classification of distinct regions within the GTV, and other clinically relevant regions, on CT images acquired on eight bladder cancer patients at the radiotherapy planning stage and thereafter at regular intervals during treatment. Statistical and fractal textural features (N=27) were calculated on the bladder, rectum and a control region identified on axial, coronal and sagittal CT images. Unsupervised classification results demonstrate that with a reduced feature set (N=3) the approach offers significant classification accuracy on axial, coronal and sagittal CT image planes and has the potential to be developed further for radiotherapy applications, particularly towards an automatic outlining approach

  16. Characterisation of radiotherapy planning volumes using textural analysis

    International Nuclear Information System (INIS)

    Nailon, William H.; Redpath, Anthony T.; McLaren, Duncan B.

    2008-01-01

    Computer-based artificial intelligence methods for classification and delineation of the gross tumour volume (GTV) on computerised tomography (CT) and magnetic resonance (MR) images do not, at present, provide the accuracy required for radiotherapy applications. This paper describes an image analysis method for classification of distinct regions within the GTV, and other clinically relevant regions, on CT images acquired on eight bladder cancer patients at the radiotherapy planning stage and thereafter at regular intervals during treatment. Statistical and fractal textural features (N=27) were calculated on the bladder, rectum and a control region identified on axial, coronal and sagittal CT images. Unsupervised classification results demonstrate that with a reduced feature set (N=3) the approach offers significant classification accuracy on axial, coronal and sagittal CT image planes and has the potential to be developed further for radiotherapy applications, particularly towards an automatic outlining approach

  17. A Bayesian network meta-analysis of whole brain radiotherapy and stereotactic radiotherapy for brain metastasis.

    Science.gov (United States)

    Yuan, Xi; Liu, Wen-Jie; Li, Bing; Shen, Ze-Tian; Shen, Jun-Shu; Zhu, Xi-Xu

    2017-08-01

    This study was conducted to compare the effects of whole brain radiotherapy (WBRT) and stereotactic radiotherapy (SRS) in treatment of brain metastasis.A systematical retrieval in PubMed and Embase databases was performed for relative literatures on the effects of WBRT and SRS in treatment of brain metastasis. A Bayesian network meta-analysis was performed by using the ADDIS software. The effect sizes included odds ratio (OR) and 95% confidence interval (CI). A random effects model was used for the pooled analysis for all the outcome measures, including 1-year distant control rate, 1-year local control rate, 1-year survival rate, and complication. The consistency was tested by using node-splitting analysis and inconsistency standard deviation. The convergence was estimated according to the Brooks-Gelman-Rubin method.A total of 12 literatures were included in this meta-analysis. WBRT + SRS showed higher 1-year distant control rate than SRS. WBRT + SRS was better for the 1-year local control rate than WBRT. SRS and WBRT + SRS had higher 1-year survival rate than the WBRT. In addition, there was no difference in complication among the three therapies.Comprehensively, WBRT + SRS might be the choice of treatment for brain metastasis.

  18. A human factor analysis of a radiotherapy accident

    International Nuclear Information System (INIS)

    Thellier, S.

    2009-01-01

    Since September 2005, I.R.S.N. studies activities of radiotherapy treatment from the angle of the human and organizational factors to improve the reliability of treatment in radiotherapy. Experienced in nuclear industry incidents analysis, I.R.S.N. analysed and diffused in March 2008, for the first time in France, the detailed study of a radiotherapy accident from the angle of the human and organizational factors. The method used for analysis is based on interviews and documents kept by the hospital. This analysis aimed at identifying the causes of the difference recorded between the dose prescribed by the radiotherapist and the dose effectively received by the patient. Neither verbal nor written communication (intra-service meetings and protocols of treatment) allowed information to be transmitted correctly in order to permit radiographers to adjust the irradiation zones correctly. This analysis highlighted the fact that during the preparation and the carrying out of the treatment, various factors led planned controls to not be performed. Finally, this analysis highlighted the fact that unsolved areas persist in the report over this accident. This is due to a lack of traceability of a certain number of key actions. The article concluded that there must be improvement in three areas: cooperation between the practitioners, control of the actions and traceability of the actions. (author)

  19. Comparative Analysis between preoperative Radiotherapy and postoperative Radiotherapy in Clinical Stage I and II Endometrial Carcinoma

    International Nuclear Information System (INIS)

    Keum, Ki Chang; Lee, Chang Geol; Chung, Eun Ji; Lee, Sang Wook; Kim, Woo Cheol; Chang, Sei Kyung; Oh, Young Taek; Suh, Chang Ok; Kim, Gwi Eon

    1995-01-01

    Purpose : To obtain the optical treatment method in patients with endometrial carcinoma(clinical stage FIGO I, II) by comparative analysis between preoperative radiotherapy(pre-op R) and postoperative radiotherapy(post-op RT). Materials and Methods : A retrospective review of 62 endometrial carcinoma patients referred to the Yonsei Cancer Center for radiotherapy between 1985 and 1991 was undertaken. Of 62 patients, 19 patients(Stage I; 12 patients, Stage II; 7 patients) received pre-op RT before TAH(Total Abdominal Hysterectomy) and BSO(Bilateral Salphingoophorectomy) (Group 1) and 43 patients( Stage 1; 32 patients, Stage 2; 11 patients) received post-op RT after TAH and BSO (Group 2). Pre-op irradiation was given 4-6 weeks prior to surgery and post-op RT was administered on 4-5 weeks following surgery. All patients exept 1 patient(Group2; ICR alone) received external irradiation. Seventy percent(13/19) of pre-op RT group and 54 percent(23/42) of post-op RT group received external pelvic irradiation and intracavitary radiation therapy(ICR). External radiation dose was 39.6-55Gy(median 45Gy) in 5-6 week through opposed AP/PA fields or 4-field box technique treating daily, five days per week, 180cGy per fraction. ICR doses were prescribed to point A(20-39.6 Gy, median 39Gy) in Group 1 and 0.5cm depth from vaginal surface (18-30 Gy, median 21Gy) in Group2. Results : The overall 5 year survival rate was 95%. No survival difference between pre-op and post-op RT group.(89.3% vs 97.7%, p>0.1) There was no survival difference by stage, grade and histology between two groups. The survival rate was not affected by presence of residual tumor of surgical specimen after pre-op RT in Group 1(p>0.1), but affected by presence of lymph node metastasis in post-op RT group(p<0.5). The complication rate of pre-op RT group was higher than post-op RT.(16% vs 5%) Conclusion : Post-op radiotherapy offers the advantages of accurate surgical-pathological staging and low complication rate

  20. Comparison and Limitations of DVH-Based NTCP Models Derived From 3D-CRT and IMRT Data for Prediction of Gastrointestinal Toxicities in Prostate Cancer Patients by Using Propensity Score Matched Pair Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Troeller, Almut [Department of Radiation Oncology, William Beaumont Health System, Royal Oak, Michigan (United States); Department of Radiotherapy and Radiation Oncology, Ludwig-Maximilians-Universität, Munich (Germany); Yan, Di, E-mail: dyan@beaumont.edu [Department of Radiation Oncology, William Beaumont Health System, Royal Oak, Michigan (United States); Marina, Ovidiu; Schulze, Derek [Department of Radiation Oncology, William Beaumont Health System, Royal Oak, Michigan (United States); Alber, Markus [Department of Oncology, Aarhus University Hospital, Aarhus (Denmark); Parodi, Katia [Department of Medical Physics, Ludwig-Maximilians-Universität, Munich (Germany); Belka, Claus; Söhn, Matthias [Department of Radiotherapy and Radiation Oncology, Ludwig-Maximilians-Universität, Munich (Germany)

    2015-02-01

    Purpose: This study compared normal tissue complication probability (NTCP) modeling of chronic gastrointestinal toxicities following prostate cancer treatment for 2 treatment modalities. Possible factors causing discrepancies in optimal NTCP model parameters between 3-dimensional conformal radiation therapy (3D-CRT) and intensity modulated RT (IMRT) were analyzed and discussed, including the impact of patient characteristics, image guidance, toxicity scoring bias, and NTCP model limitations. Methods and Materials: Rectal wall dose-volume histograms of 1115 patients treated for prostate cancer under an adaptive radiation therapy protocol were used to model gastrointestinal toxicity grade ≥2 (according to Common Terminology Criteria for Adverse Events). A total of 457 patients were treated with 3D-CRT and 658 with IMRT. 3D-CRT patients were matched to IMRT patients based on various patient characteristics, using a propensity score–based algorithm. Parameters of the Lyman equivalent uniform dose and cut-off dose logistic regression NTCP models were estimated for the 2 matched treatment modalities and the combined group. Results: After they were matched, the 3D-CRT and IMRT groups contained 275 and 550 patients with a large discrepancy of 28.7% versus 7.8% toxicities, respectively (P<.001). For both NTCP models, optimal parameters found for the 3D-CRT groups did not fit the IMRT patients well and vice versa. Models developed for the combined data overestimated NTCP for the IMRT patients and underestimated NTCP for the 3D-CRT group. Conclusions: Our analysis did not reveal a single definitive cause for discrepancies of model parameters between 3D-CRT and IMRT. Patient characteristics and bias in toxicity scoring, as well as image guidance alone, are unlikely causes of the large discrepancy of toxicities. Whether the cause was inherent to the specific NTCP models used in this study needs to be verified by future investigations. Because IMRT is increasingly used

  1. Dose profile analysis of small fields in intensity modulated radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Medel B, E. [IMSS, Centro Medico Nacional Manuel Avila Camacho, Calle 2 Nte. 2004, Barrio de San Francisco, 72090 Puebla, Pue. (Mexico); Tejeda M, G.; Romero S, K., E-mail: romsakaren@gmail.com [Benemerita Universidad Autonoma de Puebla, Facultad de Ciencias Fisico Matematicas, Av. San Claudio y 18 Sur, Ciudad Universitaria, 72570 Puebla, Pue.(Mexico)

    2015-10-15

    Full text: Small field dosimetry is getting a very important worldwide task nowadays. The use of fields of few centimeters is more common with the introduction of sophisticated techniques of radiation therapy, as Intensity Modulated Radiotherapy (IMRT). In our country the implementation of such techniques is just getting started and whit it the need of baseline data acquisition. The dosimetry under small field conditions represents a challenge for the physicists community. In this work, a dose profile analysis was done, using various types of dosimeters for further comparisons. This analysis includes the study of quality parameters as flatness, symmetry, penumbra, and other in-axis measurements. (Author)

  2. Improving patient safety in radiotherapy through error reporting and analysis

    International Nuclear Information System (INIS)

    Findlay, Ú.; Best, H.; Ottrey, M.

    2016-01-01

    Aim: To improve patient safety in radiotherapy (RT) through the analysis and publication of radiotherapy errors and near misses (RTE). Materials and methods: RTE are submitted on a voluntary basis by NHS RT departments throughout the UK to the National Reporting and Learning System (NRLS) or directly to Public Health England (PHE). RTE are analysed by PHE staff using frequency trend analysis based on the classification and pathway coding from Towards Safer Radiotherapy (TSRT). PHE in conjunction with the Patient Safety in Radiotherapy Steering Group publish learning from these events, on a triannual and summarised on a biennial basis, so their occurrence might be mitigated. Results: Since the introduction of this initiative in 2010, over 30,000 (RTE) reports have been submitted. The number of RTE reported in each biennial cycle has grown, ranging from 680 (2010) to 12,691 (2016) RTE. The vast majority of the RTE reported are lower level events, thus not affecting the outcome of patient care. Of the level 1 and 2 incidents reported, it is known the majority of them affected only one fraction of a course of treatment. This means that corrective action could be taken over the remaining treatment fractions so the incident did not have a significant impact on the patient or the outcome of their treatment. Analysis of the RTE reports demonstrates that generation of error is not confined to one professional group or to any particular point in the pathway. It also indicates that the pattern of errors is replicated across service providers in the UK. Conclusion: Use of the terminology, classification and coding of TSRT, together with implementation of the national voluntary reporting system described within this report, allows clinical departments to compare their local analysis to the national picture. Further opportunities to improve learning from this dataset must be exploited through development of the analysis and development of proactive risk management strategies

  3. How to identify rectal sub-regions likely involved in rectal bleeding in prostate cancer radiotherapy

    Science.gov (United States)

    Dréan, G.; Acosta, O.; Ospina, J. D.; Voisin, C.; Rigaud, B.; Simon, A.; Haigron, P.; de Crevoisier, R.

    2013-11-01

    Nowadays, the de nition of patient-speci c constraints in prostate cancer radiotherapy planning are solely based on dose-volume histogram (DVH) parameters. Nevertheless those DVH models lack of spatial accuracy since they do not use the complete 3D information of the dose distribution. The goal of the study was to propose an automatic work ow to de ne patient-speci c rectal sub-regions (RSR) involved in rectal bleeding (RB) in case of prostate cancer radiotherapy. A multi-atlas database spanning the large rectal shape variability was built from a population of 116 individuals. Non-rigid registration followed by voxel-wise statistical analysis on those templates allowed nding RSR likely correlated with RB (from a learning cohort of 63 patients). To de ne patient-speci c RSR, weighted atlas-based segmentation with a vote was then applied to 30 test patients. Results show the potentiality of the method to be used for patient-speci c planning of intensity modulated radiotherapy (IMRT).

  4. SU-E-T-641: Development and Verification of Automatic Reading Dose of Interest From Eclipse's DVH

    International Nuclear Information System (INIS)

    Wu, Q

    2014-01-01

    Purpose: According to clinical and research requirement, we develop a function of automatic reading dose of interest from dose volume histogram(DVH), to replace the traditional method with a mouse one by one point, and it's also verified. Methods: The DVH automatic reading function will be developed in an in-house developed radiotherapy information management system(RTIMS), which is based on Apache+PHP+MySQL. A DVH ASCII file is exported from Varian Eclipse V8.6, which includes the following contents: 1. basic information of patient; 2. dose information of plan; 3. dose information of structures, including basic information and dose volume data of target volume and organ at risk. And the default exported dose volume data also includes relative doses by 1% step and corresponding absolute doses and cumulative relative volumes, and the volumes are 4 decimal fraction. Clinically, we often need read the doses of some integer percent volumes, such as D50 and D30. So it couldn't be directly obtained from the above data, but we can use linear interpolation bye the near volumes and doses: Dx=D2−(V2−Vx)*(D2−D1)/(V2−V1), and program a function to search, read and calculate the corresponding data. And the doses of all preseted volume of interest of all structures can be automatically read one by one patient, and saved as a CSV file. To verify it, we select 24 IMRT plans for prostate cancer, and doses of interest are PTV D98/D95/D5/D2, bladder D30/D50, and rectum D25/D50. Two groups of data, using the automatic reading method(ARM) and pointed dose method(PDM), are analyzed with SPSS 16. The absolute difference=D-ARM-D-PDM, relative difference=absolute difference*100%/prescription dose(7600cGy). Results: The differences are as following: PTV D98/D95/D5/D2: −0.04%/− 0.04%/0.13%/0.19%, bladder D30/D50: −0.02%/0.01%, and rectum D25/D50: 0.03%/0.01%. Conclusion: Using this function, the error is very small, and can be neglected. It could greatly improve the

  5. SU-E-T-641: Development and Verification of Automatic Reading Dose of Interest From Eclipse's DVH

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Q [Department of Radiation Oncology, Beijing Hospital, Ministry of Health, Beijing (China)

    2014-06-15

    Purpose: According to clinical and research requirement, we develop a function of automatic reading dose of interest from dose volume histogram(DVH), to replace the traditional method with a mouse one by one point, and it's also verified. Methods: The DVH automatic reading function will be developed in an in-house developed radiotherapy information management system(RTIMS), which is based on Apache+PHP+MySQL. A DVH ASCII file is exported from Varian Eclipse V8.6, which includes the following contents: 1. basic information of patient; 2. dose information of plan; 3. dose information of structures, including basic information and dose volume data of target volume and organ at risk. And the default exported dose volume data also includes relative doses by 1% step and corresponding absolute doses and cumulative relative volumes, and the volumes are 4 decimal fraction. Clinically, we often need read the doses of some integer percent volumes, such as D50 and D30. So it couldn't be directly obtained from the above data, but we can use linear interpolation bye the near volumes and doses: Dx=D2−(V2−Vx)*(D2−D1)/(V2−V1), and program a function to search, read and calculate the corresponding data. And the doses of all preseted volume of interest of all structures can be automatically read one by one patient, and saved as a CSV file. To verify it, we select 24 IMRT plans for prostate cancer, and doses of interest are PTV D98/D95/D5/D2, bladder D30/D50, and rectum D25/D50. Two groups of data, using the automatic reading method(ARM) and pointed dose method(PDM), are analyzed with SPSS 16. The absolute difference=D-ARM-D-PDM, relative difference=absolute difference*100%/prescription dose(7600cGy). Results: The differences are as following: PTV D98/D95/D5/D2: −0.04%/− 0.04%/0.13%/0.19%, bladder D30/D50: −0.02%/0.01%, and rectum D25/D50: 0.03%/0.01%. Conclusion: Using this function, the error is very small, and can be neglected. It could greatly improve the

  6. Moving from gamma passing rates to patient DVH-based QA metrics in pretreatment dose QA

    Energy Technology Data Exchange (ETDEWEB)

    Zhen, Heming; Nelms, Benjamin E.; Tome, Wolfgang A. [Department of Medical Physics, University of Wisconsin, Madison, Wisconsin 53705 (United States); Department of Human Oncology, University of Wisconsin, Madison, Wisconsin 53792 and Canis Lupus LLC, Merrimac, Wisconsin 53561 (United States); Department of Medical Physics, University of Wisconsin, Madison, Wisconsin 53705 and Department of Human Oncology, University of Wisconsin, Madison, Wisconsin 53792 (United States)

    2011-10-15

    Purpose: The purpose of this work is to explore the usefulness of the gamma passing rate metric for per-patient, pretreatment dose QA and to validate a novel patient-dose/DVH-based method and its accuracy and correlation. Specifically, correlations between: (1) gamma passing rates for three 3D dosimeter detector geometries vs clinically relevant patient DVH-based metrics; (2) Gamma passing rates of whole patient dose grids vs DVH-based metrics, (3) gamma passing rates filtered by region of interest (ROI) vs DVH-based metrics, and (4) the capability of a novel software algorithm that estimates corrected patient Dose-DVH based on conventional phan-tom QA data are analyzed. Methods: Ninety six unique ''imperfect'' step-and-shoot IMRT plans were generated by applying four different types of errors on 24 clinical Head/Neck patients. The 3D patient doses as well as the dose to a cylindrical QA phantom were then recalculated using an error-free beam model to serve as a simulated measurement for comparison. Resulting deviations to the planned vs simulated measured DVH-based metrics were generated, as were gamma passing rates for a variety of difference/distance criteria covering: dose-in-phantom comparisons and dose-in-patient comparisons, with the in-patient results calculated both over the whole grid and per-ROI volume. Finally, patient dose and DVH were predicted using the conventional per-beam planar data as input into a commercial ''planned dose perturbation'' (PDP) algorithm, and the results of these predicted DVH-based metrics were compared to the known values. Results: A range of weak to moderate correlations were found between clinically relevant patient DVH metrics (CTV-D95, parotid D{sub mean}, spinal cord D1cc, and larynx D{sub mean}) and both 3D detector and 3D patient gamma passing rate (3%/3 mm, 2%/2 mm) for dose-in-phantom along with dose-in-patient for both whole patient volume and filtered per-ROI. There was

  7. A Comparative Dosimetric Study of Adjuvant 3D Conformal Radiotherapy for Operable Stomach Cancer Versus AP-PA Conventional Radiotherapy in NCI-Cairo

    International Nuclear Information System (INIS)

    El-Hossiny, H.A.; Diab, N.A.; El-Taher, M.M.

    2009-01-01

    This study was to compare this multiple field conformal technique to the AP-PA technique with respect to target volume coverage and dose to normal tissues. Materials and Methods: Seventeen patients with stages II-III denocarcinoma of the stomach were treated with adjuvant postoperative chemoradiotherapy presented to radiotherapy department in National Cancer Institute, Cairo in period between February 2009 to March 2010 using 3D conformal radiotherapy technique that consisted of a mono isocentric arrangement employing 4-6 radiation fields. For each patient, a second radiotherapy treatment plan was done using an antroposterior (AP-PA) fields, the two techniques were then compared using dose volume histogram (DVH) analysis. Results: Comparing different DVHs, it was found that the planning target volume (PTV) was adequately covered in both (3D and 2D) plans while the left kidney and spinal cord demonstrate lower radiation doses on using the conformal technique. The liver doses is higher in the 3D tecq, but still well below liver tolerance. Conclusions: Both 3D conformal radiotherapy and AP-PA conventional techniques doses are within range of normal tissues tolerance. Regarding the left kidney and spinal cord the 3D conformal radiotherapy is superior than the AP-PA conventional techniques but with higher doses to the liver in the 3D conformal radiotherapy compared to the AP-PA conventional techniques

  8. Hyperfractionated or accelerated radiotherapy in head and neck cancer: a meta-analysis

    DEFF Research Database (Denmark)

    Bourhis, J.; Overgaard, Jens; Audry, H.

    2006-01-01

    BACKGROUND: Several trials have studied the role of unconventional fractionated radiotherapy in head and neck squamous cell carcinoma, but the effect of such treatment on survival is not clear. The aim of this meta-analysis was to assess whether this type of radiotherapy could improve survival. M...

  9. Utility-adjusted analysis of the cost of palliative radiotherapy for bone metastases

    International Nuclear Information System (INIS)

    Barton, M.B.; Jacob, S.A.

    2003-01-01

    Palliative radiotherapy is effective in the treatment of bone metastases but is under-utilized, possibly because it is perceived to be expensive. We performed a cost-utility analysis of palliative radiotherapy for bone metastases, evaluating both the actual cost of radiotherapy as well as its impact on quality of life by adjusting for the variation in response to treatment. Hospital records between July 1991 and July 1996 were reviewed to ascertain the number of patients treated with palliative radiotherapy for bone metastases, the average number of fields of radiation delivered to each patient and the average duration of survival. Partial and complete response rates to palliative radiotherapy were obtained from a review of all published randomized controlled trials of radiation treatment of bone metastases. Utility values were assigned to the response rates, and an overall adjusted response rate to radiotherapy was derived. The cost of delivering a field of radiation was calculated. The total cost was divided by the total number of response months to give a utility-adjusted cost per month of palliative radiotherapy. The utility-adjusted cost per month of palliative radiotherapy of bone metastases was found to be AUS$ 100 per month or AUS$ 1200 per utility-adjusted life-year. This study demonstrates that, contrary to popular perception, palliative radiotherapy is a cost-effective treatment modality for bone metastases. Copyright (2003) Blackwell Science Pty Ltd

  10. Analysis for prognostic factors of radiotherapy for esophageal squamous cell carcinoma

    International Nuclear Information System (INIS)

    Nakano, Takashi; Ito, Jun; Ito, Ichiro; Yamanaka, Mikio; Suto, Hisao; Mitsuhashi, Norio; Niibe, Hideo

    1984-01-01

    Two hundred and fifty patients with squamous cell carcinoma of the esophagus were treated at our department from 1969 to 1981 with radiotherapy involving radiation alone and pre-and/or post-operative radiotherapy. For 167 patients receiving radiotherapy alone, 144 were inoperable cases and only 60 patients could be radically treated. The others were palliative treated patients because of the locally advanced state or distant metastases or severe complications. For 83 patients receiving pre-and/or post-operative radiotherapy, 62 were radically treated. Results of radiotherapy were analyzed to elucidate factors responsible for these prognosis. Relative 5 years survival rates for radically treated patients were 26% in radiotherapy alone and 20% in pre-and/or post-operative radiotherapy respectively. In radiotherapy alone, quite a good prognoses could be obtained in the patients with tumors less than 5cm at radiografical finding (42% for 5 yrs), with tumors located in Ei, Ea esophagus (40%), with tumors of serrative and tumorous X-P types (48%, 43%, respectively) and with good radiation response at the end of radiotherapy (54%). From the analysis of 12 patients surviving more than 5 years from onset of treatment, not only tumor size less than 5cm but also radiation response was major factor responsible for the prognosis. It might be important to treat patients precisely according to their own clinical characteristics and considering tumor host relationship. (author)

  11. Quality assurance in radiotherapy: analysis of the causes of not starting or early radiotherapy withdrawal

    International Nuclear Information System (INIS)

    Arenas, Meritxell; Sabater, Sebastià; Gascón, Marina; Henríquez, Ivan; Bueno, M José; Rius, Àngels; Rovirosa, Àngels; Gómez, David; Lafuerza, Anna; Biete, Albert; Colomer, Jordi

    2014-01-01

    The aim of this study was to analyse the reasons for not starting or for early of radiotherapy at the Radiation Oncology Department. All radiotherapy treatments from March 2010 to February 2012 were included. Early withdrawals from treatment those that never started recorded. Clinical, demographic and dosimetric variables were also noted. From a total of 3250 patients treated and reviewed, 121 (4%) did not start or complete the planned treatment. Of those, 63 (52%) did not receive any radiotherapy fraction and 58 (48%) did not complete the course, 74% were male and 26% were female. The mean age was 67 ± 13 years. The most common primary tumour was lung (28%), followed by rectum (16%). The aim of treatment was 62% radical and 38% palliative, 44% of patients had metastases; the most common metastatic site was bone, followed by brain. In 38% of cases (46 patients) radiotherapy was administered concomitantly with chemotherapy (10 cases (22%) were rectal cancers). The most common reason for not beginning or for early withdrawal of treatment was clinical progression (58/121, 48%). Of those, 43% died (52/121), 35 of them because of the progression of the disease and 17 from other causes. Incomplete treatment regimens were due to toxicity (12/121 (10%), of which 10 patients underwent concomitant chemotherapy for rectal cancer). The number of patients who did not complete their course of treatment is low, which shows good judgement in indications and patient selection. The most common reason for incomplete treatments was clinical progression. Rectal cancer treated with concomitant chemotherapy was the most frequent reason of the interruption of radiotherapy for toxicity

  12. SU-F-T-285: Evaluation of a Patient DVH-Based IMRT QA System

    Energy Technology Data Exchange (ETDEWEB)

    Zhen, H; Redler, G; Chu, J; Turian, J [Rush University Medical Center, Chicago, IL (United States)

    2016-06-15

    Purpose: To evaluate the clinical performance of a patient DVH-based QA system for prostate VMAT QA. Methods: Mobius3D(M3D) is a QA software with an independent beam model and dose engine. The MobiusFX(MFX) add-on predicts patient dose using treatment machine log files. We commissioned the Mobius beam model in two steps. First, the stock beam model was customized using machine commissioning data, then verified against the TPS with 12 simple phantom plans and 7 clinical 3D plans. Secondly, the Dosimetric Leaf Gap(DLG) in the Mobius model was fine-tuned for VMAT treatment based on ion chamber measurements for 6 clinical VMAT plans. Upon successful commissioning, we retrospectively performed IMRT QA for 12 VMAT plans with the Mobius system as well as the ArcCHECK-3DVH system. Selected patient DVH values (PTV D95, D50; Bladder D2cc, Dmean; Rectum D2cc) were compared between TPS, M3D, MFX, and 3DVH. Results: During the first commissioning step, TPS and M3D calculated target Dmean for 3D plans agree within 0.7%±0.7%, with 3D gamma passing rates of 98%±2%. In the second commissioning step, the Mobius DLG was adjusted by 1.2mm from the stock value, reducing the average difference between MFX calculation and ion chamber measurement from 3.2% to 0.1%. In retrospective prostate VMAT QA, 5 of 60 MFX calculated DVH values have a deviation greater than 5% compared to TPS. One large deviation at high dose level was identified as a potential QA failure. This echoes the 3DVH QA result, which identified 2 instances of large DVH deviation on the same structure. For all DVH’s evaluated, M3D and MFX show high level of agreement (0.1%±0.2%), indicating that the observed deviation is likely from beam modelling differences rather than delivery errors. Conclusion: Mobius system provides a viable solution for DVH based VMAT QA, with the capability of separating TPS and delivery errors.

  13. SU-F-T-285: Evaluation of a Patient DVH-Based IMRT QA System

    International Nuclear Information System (INIS)

    Zhen, H; Redler, G; Chu, J; Turian, J

    2016-01-01

    Purpose: To evaluate the clinical performance of a patient DVH-based QA system for prostate VMAT QA. Methods: Mobius3D(M3D) is a QA software with an independent beam model and dose engine. The MobiusFX(MFX) add-on predicts patient dose using treatment machine log files. We commissioned the Mobius beam model in two steps. First, the stock beam model was customized using machine commissioning data, then verified against the TPS with 12 simple phantom plans and 7 clinical 3D plans. Secondly, the Dosimetric Leaf Gap(DLG) in the Mobius model was fine-tuned for VMAT treatment based on ion chamber measurements for 6 clinical VMAT plans. Upon successful commissioning, we retrospectively performed IMRT QA for 12 VMAT plans with the Mobius system as well as the ArcCHECK-3DVH system. Selected patient DVH values (PTV D95, D50; Bladder D2cc, Dmean; Rectum D2cc) were compared between TPS, M3D, MFX, and 3DVH. Results: During the first commissioning step, TPS and M3D calculated target Dmean for 3D plans agree within 0.7%±0.7%, with 3D gamma passing rates of 98%±2%. In the second commissioning step, the Mobius DLG was adjusted by 1.2mm from the stock value, reducing the average difference between MFX calculation and ion chamber measurement from 3.2% to 0.1%. In retrospective prostate VMAT QA, 5 of 60 MFX calculated DVH values have a deviation greater than 5% compared to TPS. One large deviation at high dose level was identified as a potential QA failure. This echoes the 3DVH QA result, which identified 2 instances of large DVH deviation on the same structure. For all DVH’s evaluated, M3D and MFX show high level of agreement (0.1%±0.2%), indicating that the observed deviation is likely from beam modelling differences rather than delivery errors. Conclusion: Mobius system provides a viable solution for DVH based VMAT QA, with the capability of separating TPS and delivery errors.

  14. Incorporating big data into treatment plan evaluation: Development of statistical DVH metrics and visualization dashboards.

    Science.gov (United States)

    Mayo, Charles S; Yao, John; Eisbruch, Avraham; Balter, James M; Litzenberg, Dale W; Matuszak, Martha M; Kessler, Marc L; Weyburn, Grant; Anderson, Carlos J; Owen, Dawn; Jackson, William C; Haken, Randall Ten

    2017-01-01

    To develop statistical dose-volume histogram (DVH)-based metrics and a visualization method to quantify the comparison of treatment plans with historical experience and among different institutions. The descriptive statistical summary (ie, median, first and third quartiles, and 95% confidence intervals) of volume-normalized DVH curve sets of past experiences was visualized through the creation of statistical DVH plots. Detailed distribution parameters were calculated and stored in JavaScript Object Notation files to facilitate management, including transfer and potential multi-institutional comparisons. In the treatment plan evaluation, structure DVH curves were scored against computed statistical DVHs and weighted experience scores (WESs). Individual, clinically used, DVH-based metrics were integrated into a generalized evaluation metric (GEM) as a priority-weighted sum of normalized incomplete gamma functions. Historical treatment plans for 351 patients with head and neck cancer, 104 with prostate cancer who were treated with conventional fractionation, and 94 with liver cancer who were treated with stereotactic body radiation therapy were analyzed to demonstrate the usage of statistical DVH, WES, and GEM in a plan evaluation. A shareable dashboard plugin was created to display statistical DVHs and integrate GEM and WES scores into a clinical plan evaluation within the treatment planning system. Benchmarking with normal tissue complication probability scores was carried out to compare the behavior of GEM and WES scores. DVH curves from historical treatment plans were characterized and presented, with difficult-to-spare structures (ie, frequently compromised organs at risk) identified. Quantitative evaluations by GEM and/or WES compared favorably with the normal tissue complication probability Lyman-Kutcher-Burman model, transforming a set of discrete threshold-priority limits into a continuous model reflecting physician objectives and historical experience

  15. [Automatic Extraction and Analysis of Dosimetry Data in Radiotherapy Plans].

    Science.gov (United States)

    Song, Wei; Zhao, Di; Lu, Hong; Zhang, Biyun; Ma, Jun; Yu, Dahai

    To improve the efficiency and accuracy of extraction and analysis of dosimetry data in radiotherapy plans for a batch of patients. With the interface function provided in Matlab platform, a program was written to extract the dosimetry data exported from treatment planning system in DICOM RT format and exported the dose-volume data to an Excel file with the SPSS compatible format. This method was compared with manual operation for 14 gastric carcinoma patients to validate the efficiency and accuracy. The output Excel data were compatible with SPSS in format, the dosimetry data error for PTV dose interval of 90%-98%, PTV dose interval of 99%-106% and all OARs were -3.48E-5 ± 3.01E-5, -1.11E-3 ± 7.68E-4, -7.85E-5 ± 9.91E-5 respectively. Compared with manual operation, the time required was reduced from 5.3 h to 0.19 h and input error was reduced from 0.002 to 0. The automatic extraction of dosimetry data in DICOM RT format for batch patients, the SPSS compatible data exportation, quick analysis were achieved in this paper. The efficiency of clinical researches based on dosimetry data analysis of large number of patients will be improved with this methods.

  16. Technical Note: Introduction of variance component analysis to setup error analysis in radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Matsuo, Yukinori, E-mail: ymatsuo@kuhp.kyoto-u.ac.jp; Nakamura, Mitsuhiro; Mizowaki, Takashi; Hiraoka, Masahiro [Department of Radiation Oncology and Image-applied Therapy, Kyoto University, 54 Shogoin-Kawaharacho, Sakyo, Kyoto 606-8507 (Japan)

    2016-09-15

    Purpose: The purpose of this technical note is to introduce variance component analysis to the estimation of systematic and random components in setup error of radiotherapy. Methods: Balanced data according to the one-factor random effect model were assumed. Results: Analysis-of-variance (ANOVA)-based computation was applied to estimate the values and their confidence intervals (CIs) for systematic and random errors and the population mean of setup errors. The conventional method overestimates systematic error, especially in hypofractionated settings. The CI for systematic error becomes much wider than that for random error. The ANOVA-based estimation can be extended to a multifactor model considering multiple causes of setup errors (e.g., interpatient, interfraction, and intrafraction). Conclusions: Variance component analysis may lead to novel applications to setup error analysis in radiotherapy.

  17. Technical Note: Introduction of variance component analysis to setup error analysis in radiotherapy

    International Nuclear Information System (INIS)

    Matsuo, Yukinori; Nakamura, Mitsuhiro; Mizowaki, Takashi; Hiraoka, Masahiro

    2016-01-01

    Purpose: The purpose of this technical note is to introduce variance component analysis to the estimation of systematic and random components in setup error of radiotherapy. Methods: Balanced data according to the one-factor random effect model were assumed. Results: Analysis-of-variance (ANOVA)-based computation was applied to estimate the values and their confidence intervals (CIs) for systematic and random errors and the population mean of setup errors. The conventional method overestimates systematic error, especially in hypofractionated settings. The CI for systematic error becomes much wider than that for random error. The ANOVA-based estimation can be extended to a multifactor model considering multiple causes of setup errors (e.g., interpatient, interfraction, and intrafraction). Conclusions: Variance component analysis may lead to novel applications to setup error analysis in radiotherapy.

  18. Adjuvant Versus Salvage Radiotherapy for Patients With Adverse Pathological Findings Following Radical Prostatectomy: A Decision Analysis

    Directory of Open Access Journals (Sweden)

    Christopher J. D. Wallis MD

    2017-05-01

    Full Text Available Background: Patients undergoing surgery for prostate cancer who have adverse pathological findings experience high rates of recurrence. While there are data supporting adjuvant radiotherapy compared to a wait-and-watch strategy to reduce recurrence rates, there are no randomized controlled trials comparing adjuvant radiotherapy with the other standard of care, salvage radiotherapy (radiotherapy administered at the time of recurrence. Methods: We constructed a health state transition (Markov model employing two-dimensional Monte Carlo simulation using a lifetime horizon to compare the quality-adjusted survival associated with postoperative strategies using adjuvant or salvage radiotherapy. Prior to analysis, we calibrated and validated our model using the results of previous randomized controlled trials. We considered clinically important oncological health states from immediately postoperative to prostate cancer–specific death, commonly described complications from prostate cancer treatment, and other causes of mortality. Transition probabilities and utilities for disease states were derived from a literature search of MEDLINE and expert consensus. Results: Salvage radiotherapy was associated with an increased quality-adjusted life expectancy (QALE (58.3 months as compared with adjuvant radiotherapy (53.7 months, a difference of 4.6 months (standard deviation 8.8. Salvage radiotherapy had higher QALE in 53% of hypothetical cohorts. There was a minimal difference in overall life expectancy (-0.1 months. Examining recurrence rates, our model showed validity when compared with available randomized controlled data. Conclusions: A salvage radiotherapy strategy appears to provide improved QALE for patients with adverse pathological findings following radical prostatectomy, compared with adjuvant radiotherapy. As these findings reflect, population averages, specific patient and tumor factors, and patient preferences remain central for individualized

  19. Quantitative analysis of results for quality assurance in radiotherapy

    International Nuclear Information System (INIS)

    Passaro, Bruno Martins

    2011-01-01

    The linear accelerators represent the most important, practical and versatile source of ionizing radiation in radiotherapy. These functional characteristics influence the geometric and dosimetric accuracy of therapeutic doses applied to patients. The performance of this equipment may vary due to electronic defects, component failures or mechanical breakdowns, or may vary due to the deterioration and aging of components. Maintaining the quality of care depends on the stability of the accelerators and quality control of the institutions to monitor deviations in the parameters of the beam. The aim of this study is to assess and analyze the stability of the calibration factor of linear accelerators, as well as the other dosimetric parameters normally included in a program of quality control in radiotherapy. The average calibration factors of the accelerators for the period of approximately four years for the Clinac 600C and Clinac 6EX were (0,998 ± 0,012) and (0,996 ± 0,014), respectively. For the Clinac 2100CD 6 MV and 15 MV was (1,008 ± 0,009) and (1,006 ± 0,010), respectively, in a period of approximately four years. Statistical analysis of the three linear accelerators was found that the coefficient of variation of calibration factors had values below 2% which shows a consistency in the data. By calculating the normal distribution of calibration factors, we found that for the Clinac 600C and Clinac 2100CD, is an expected probability that more than 90% of cases the values are within acceptable limits according to the TG-142, while for the Clinac 6EX is expected around 85% since this had several exchanges of accelerator components. The values of TPR 20,10 of three accelerators are practically constant and within acceptable limits according to the TG-142. It can be concluded that a detailed study of data from the calibration factor of the accelerators and TPR20,10 from a quantitative point of view, is extremely useful in a quality assurance program. (author)

  20. The integration of DVH-based planning aspects into a convex intensity modulated radiation therapy optimization framework

    Energy Technology Data Exchange (ETDEWEB)

    Kratt, Karin [Faculty of Mathematics, Technical University of Kaiserslautern, Kaiserslautern (Germany); Scherrer, Alexander [Department of Optimization, Fraunhofer Institute for Industrial Mathematics (ITWM), Kaiserslautern (Germany)], E-mail: alexander.scherrer@itwm.fraunhofer.de

    2009-06-21

    The formulation of intensity modulated radiation therapy (IMRT) planning aspects frequently uses the dose-volume histogram (DVH), whereas plan computations often happen in the more desirable convex IMRT optimization framework. Inspired by a recent publication of Zinchenko et al (2008 Phys. Med. Biol. 53 3231-50), this work addresses the integration of DVH-based planning aspects into this framework from a general point of view. It first provides the basic mathematical requirements on the evaluation functions in order to support such an incorporation. Then it introduces the condition number as a description for how precisely DVH-based planning aspects can be reformulated in terms of evaluation functions. Exemplary numerical studies for the generalized equivalent uniform dose and a physical constraint function show the influence of function parameter values and DVH approximation on the condition number. The work concludes by formulating the aspects that should be taken into account for an appropriate integration of DVH-based planning aspects. (note)

  1. The integration of DVH-based planning aspects into a convex intensity modulated radiation therapy optimization framework

    International Nuclear Information System (INIS)

    Kratt, Karin; Scherrer, Alexander

    2009-01-01

    The formulation of intensity modulated radiation therapy (IMRT) planning aspects frequently uses the dose-volume histogram (DVH), whereas plan computations often happen in the more desirable convex IMRT optimization framework. Inspired by a recent publication of Zinchenko et al (2008 Phys. Med. Biol. 53 3231-50), this work addresses the integration of DVH-based planning aspects into this framework from a general point of view. It first provides the basic mathematical requirements on the evaluation functions in order to support such an incorporation. Then it introduces the condition number as a description for how precisely DVH-based planning aspects can be reformulated in terms of evaluation functions. Exemplary numerical studies for the generalized equivalent uniform dose and a physical constraint function show the influence of function parameter values and DVH approximation on the condition number. The work concludes by formulating the aspects that should be taken into account for an appropriate integration of DVH-based planning aspects. (note)

  2. Analysis of cervical cancer cells treated with radiotherapy or arterial infusion chemotherapy

    International Nuclear Information System (INIS)

    Izutu, Toshihiko; Nishiya, Iwao

    1995-01-01

    The present study was designed to analyze cervical cancer cells treated with radiotherapy or intraarterial infusion of CDDP using image analysis. Total nuclear extinction (TE), 5 N-exceeding rate (5 NER) and nuclear area (NA) gradually increased following irradiation, in cervical cancer cases. TE and 5 NER increased markedly following radiotherapy in good response cases. TE, 5 NER and NA were not-changed following irradiation in poor response cases. 5 NER, in good prognostic cases was higher than in poor prognostic cases, significantly among cervical cancer cases treated with radiotherapy. 5 NER and NA increased dramatically in good response cases treated with intraarterial infusion of CDDP. (author)

  3. Analysis of positioning errors in radiotherapy; Analyse des erreurs de positionnement en radiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Josset-Gaudaire, S.; Lisbona, A.; Llagostera, C.; Delpon, G.; Chiavassa, S.; Brunet, G. [Service de physique medicale, ICO Rene-Gauducheau, Saint Herblain (France); Rousset, S.; Nerriere, E.; Leblanc, M. [Service de radiotherapie, ICO Rene-Gauducheau, Saint Herblain (France)

    2011-10-15

    Within the frame of a study of control imagery management in radiotherapy, the authors report the study of positioning errors associated with control imagery in order to give an overview of practice and to help the adjustment or definition of action levels for clinical practice. Twenty groups of patients have been defined by considering tumour locations (head, ENT, thorax, breast, abdomen, and pelvis), treatment positions, immobilization systems and imagery systems. Positioning errors have thus been analyzed for 340 patients. Aspects and practice to be improved are identified. Short communication

  4. SU-E-T-531: Large--Scale DVH Quality Study: Correlated Aims Lead Relaxations

    Energy Technology Data Exchange (ETDEWEB)

    Nohadani, O; Roy, A [Northwestern University, Evanston, IL (United States); Das, I [Indiana University- School of Medicine, Indianapolis, IN (United States)

    2015-06-15

    Purpose: Intensity modulated radiation therapy plans are designed to optimally target a tumor while sparing surrounding tissue. Desired dose distributions are iteratively approached via inverse planning. This leads to tradeoffs between clinical objectives for the planning target volume (PTV), organs at risk, and normal tissues. Dose volume histogram (DVHs) related aims are followed that are either institutional or internationally recommended. We analyze common goals and identify potential reasons that often lead to tradeoffs. Methods: 524 IMRT plans for various tumor sites were analyzed based on the main institutional DVH goal for PTV (D95) and the recommendations by ICRU-83 (D2, D50, and D98). Robust statistical tools are developed and applied to ensure that the results are immune to data uncertainties. The probability of violation was measured for each of the DVH goals based on the frequency of not meeting recommended doses. Conditional probabilities for satisfying and/or violating DVH aims were computed to test the hypothesized pair-wise relations between DVH aims. For example, for plans that satisfied D50, the probability of violating D98 was computed via P(D98 < 95% | 98% ≤ D50 ≤ 102%). The equality constraint D50 = 100% was relaxed to encompass the range [98,102]%. Results: A large majority of cases (88%) satisfied the institutional goal for PTV of D95 ≤ 95%. Similar consensus existed for D98. 51% of cases satisfied D2 ≥ 107%. However, only 18% of cases satisfied D50. The conditional probability showed correlations amongst the studied DVH goals. In fact, a negative correlation was revealed between D50 and D95 (and D98), suggesting that these competing goals cannot be satisfied concurrently. Conclusion: The majority of plans followed the institutional guidelines. The reason for their deviation from international recommendations seems to be that the latter goals are competing and cannot be satisfied concurrently in clinical practice.

  5. Survival after radiotherapy in gastric cancer: Systematic review and meta-analysis

    International Nuclear Information System (INIS)

    Valentini, Vincenzo; Cellini, Francesco; Minsky, Bruce D.; Mattiucci, Gian Carlo; Balducci, Mario; D'Agostino, Giuseppe; D'Angelo, Elisa; Dinapoli, Nicola; Nicolotti, Nicola; Valentini, Chiara; La Torre, Giuseppe

    2009-01-01

    Background and purpose: A systematic review and meta-analysis was performed to assess the impact of radiotherapy on both 3- and 5-year survival in patients with resectable gastric cancer. Methods: Randomized Clinical Trials (RCTs) in which radiotherapy, (preoperative, postoperative and/or intraoperative), was compared with surgery alone or surgery plus chemotherapy in resectable gastric cancer were identified by searching web-based databases and supplemented by manual examination of reference lists. Meta-analysis was performed using Risk Ratios (RRs). Random or fixed effects models were used to combine data. The methodological quality was evaluated by Chalmers' score. Results: Radiotherapy had a significant impact on 5-year survival. Using an intent to treat (ITT) and a Per Protocol (PP) analysis, the overall 5-year RR was 1.26 (95% CI: 1.08-1.48; NNT = 17) and 1.31 (95% CI: 1.04-1.66; NNT = 13), respectively. Although the quality of the studies was variable, the data were consistent and no clear publication bias was found. Conclusion: This meta-analysis showed a statistically significant 5-year survival benefit with the addition of radiotherapy in patients with resectable gastric cancer. Radiotherapy remains a standard component in the treatment of resectable gastric cancer and new RCTs need to address the impact of new conformal radiotherapy technologies.

  6. Location of radiotherapy centers: An exploratory geographic analysis for Belgium

    International Nuclear Information System (INIS)

    Cotteels, C.; Peeters, D.; Coucke, P.A.; Thomas, I.

    2012-01-01

    Purpose. - The distance between the patient's home and a radiotherapy department may represent a hurdle for the patient and influence treatment choice. Therefore, it is necessary to check whether the geographical distribution of radiotherapy centers is in accordance with cancer incidence, taking also into account the cost of travelling to the radiotherapy department. The objective of this study is double; first, to map the current locations of radiotherapy centers across the country and second, to evaluate the observed spatial disparities with appropriate tools. Materials and methods. - A model of operational research (P-median) is used to suggest the optimal locations and allocations and to compare them with the current situation. This is an exploratory study with simple inputs. It helps to better understand the current geographical distribution of radiotherapy centers in Belgium as well as its possible limitations. Results-conclusion. - It appears that the current situation is on the average acceptable in terms of accessibility to the service and that the method presents huge potentialities for decision making so as to yield a spatial system that is both efficient and equitable. (authors)

  7. Regression and local control rates after radiotherapy for jugulotympanic paragangliomas: Systematic review and meta-analysis

    International Nuclear Information System (INIS)

    Hulsteijn, Leonie T. van; Corssmit, Eleonora P.M.; Coremans, Ida E.M.; Smit, Johannes W.A.; Jansen, Jeroen C.; Dekkers, Olaf M.

    2013-01-01

    The primary treatment goal of radiotherapy for paragangliomas of the head and neck region (HNPGLs) is local control of the tumor, i.e. stabilization of tumor volume. Interestingly, regression of tumor volume has also been reported. Up to the present, no meta-analysis has been performed giving an overview of regression rates after radiotherapy in HNPGLs. The main objective was to perform a systematic review and meta-analysis to assess regression of tumor volume in HNPGL-patients after radiotherapy. A second outcome was local tumor control. Design of the study is systematic review and meta-analysis. PubMed, EMBASE, Web of Science, COCHRANE and Academic Search Premier and references of key articles were searched in March 2012 to identify potentially relevant studies. Considering the indolent course of HNPGLs, only studies with ⩾12 months follow-up were eligible. Main outcomes were the pooled proportions of regression and local control after radiotherapy as initial, combined (i.e. directly post-operatively or post-embolization) or salvage treatment (i.e. after initial treatment has failed) for HNPGLs. A meta-analysis was performed with an exact likelihood approach using a logistic regression with a random effect at the study level. Pooled proportions with 95% confidence intervals (CI) were reported. Fifteen studies were included, concerning a total of 283 jugulotympanic HNPGLs in 276 patients. Pooled regression proportions for initial, combined and salvage treatment were respectively 21%, 33% and 52% in radiosurgery studies and 4%, 0% and 64% in external beam radiotherapy studies. Pooled local control proportions for radiotherapy as initial, combined and salvage treatment ranged from 79% to 100%. Radiotherapy for jugulotympanic paragangliomas results in excellent local tumor control and therefore is a valuable treatment for these types of tumors. The effects of radiotherapy on regression of tumor volume remain ambiguous, although the data suggest that regression can

  8. 3D Conformal radiotherapy for gastric cancer-results of a comparative planning study

    International Nuclear Information System (INIS)

    Leong, Trevor; Willis, David; Joon, Daryl Lim; Condron, Sara; Hui, Andrew; Ngan, Samuel Y.K.

    2005-01-01

    Background and purpose: Many radiation oncologists are reluctant to use anteroposterior-posteroanterior (AP-PA) field arrangements when treating gastric cancer with adjuvant postoperative radiotherapy due to concerns about normal tissue toxicity, particularly in relation to the kidneys and spinal cord. In this report, we describe a multiple-field conformal radiotherapy technique, and compare this technique to the more commonly used AP-PA technique that was used in the recently reported Intergroup study (INT0116). Materials and methods: Fifteen patients with stages II-IV adenocarcinoma of the stomach were treated with adjuvant postoperative chemoradiotherapy using a standardised 3D conformal radiotherapy technique that consisted of a 'split-field', mono-isocentric arrangement employing 6 radiation fields. For each patient, a second radiotherapy treatment plan was generated utilising AP-PA fields. The two techniques were then compared for target volume coverage and dose to normal tissues using dose volume histogram (DVH) analysis. Results: The conformal technique provides more adequate coverage of the target volume with 99% of the planning target volume (PTV) receiving 95% of the prescribed dose, compared to 93% using AP-PA fields. Comparative DVHs for the right kidney, left kidney and spinal cord demonstrate lower radiation doses using the conformal technique, and although the liver dose is higher, it is still well below liver tolerance. Conclusions: 3D conformal radiotherapy produces superior dose distributions and reduced radiation doses to the kidneys and spinal cord compared to AP-PA techniques, with the potential to reduce treatment toxicity

  9. Analysis of the actual number of physicians in radiotherapy units in Germany

    International Nuclear Information System (INIS)

    Guttenberger, R.; Witucki, G.

    2002-01-01

    Background: Physician workload directly influences the ability of an institution to provide high standards in radiotherapy services. Materials and Methods: Data of 189 radiotherapy units of the DEGRO survey 2000 complemented and corrected (Table 1) are analyzed with simple and multiple linear regression (models in Table 2). Results: In 21 private radiotherapy facilities actual numbers of physicians split up in 0.19 for every 1,000 megavoltage courses per year, 1.8 per megavoltage unit, 0.68 for every ten beds for inpatients minus 0.67 or plus 1.2 physicians per facility providing radiotherapy only or combined with other services, respectively. Radiotherapy units in hospitals were analyzed in two groups, i.e. radiotherapy only (n=69) or in combination with other services (n=59). In the latter, reported numbers of physicians split up in 3.2 for every 1,000 megavoltage courses per year, minus 0.13 per megavoltage unit, 0.87 for every ten beds for inpatients, plus 2.2 per facility. Units providing radiotherapy only had 0.86 physicians for every 1,000 megavoltage courses per year plus 1.0 per megavoltage unit plus 0.97 for every ten beds plus 1.0 per facility. In 36 radiotherapy university clinics actual numbers of physicians split up in 2.4 for every 1,000 megavoltage courses per year, 1.7 per megavoltage unit, 0.86 for every ten beds for inpatients, plus 1.5 per clinic. For confidence limits see Table 3, for results of univariate analysis Figures 1 and 2. Conclusion: In German radiotherapy facilities, physician workload varies considerably. It exceeds that reported for the USA by a substantial margin. (orig.) [de

  10. Clinical-dosimetric analysis of measures of dysphagia including gastrostomy-tube dependence among head and neck cancer patients treated definitively by intensity-modulated radiotherapy with concurrent chemotherapy

    International Nuclear Information System (INIS)

    Li, Baoqing; Chen, Allen M; Li, Dan; Lau, Derick H; Farwell, D Gregory; Luu, Quang; Rocke, David M; Newman, Kathleen; Courquin, Jean; Purdy, James A

    2009-01-01

    To investigate the association between dose to various anatomical structures and dysphagia among patients with head and neck cancer treated by definitive intensity-modulated radiotherapy (IMRT) and concurrent chemotherapy. Thirty-nine patients with squamous cancer of the head and neck were treated by definitive concurrent chemotherapy and IMRT to a median dose of 70 Gy (range, 68 to 72). In each patient, a gastrostomy tube (GT) was prophylacticly placed prior to starting treatment. Prolonged GT dependence was defined as exceeding the median GT duration of 192 days. Dysphagia was scored using standardized quality-of-life instruments. Dose-volume histogram (DVH) data incorporating the superior/middle pharyngeal constrictors (SMPC), inferior pharyngeal constrictor (IPC), cricoid pharyngeal inlet (CPI), and cervical esophagus (CE) were analyzed in relation to prolonged GT dependence, dysphagia, and weight loss. At 3 months and 6 months after treatment, 87% and 44% of patients, respectively, were GT dependent. Spearman's ρ analysis identified statistical correlations (p < 0.05) between prolonged GT dependence or high grade dysphagia with IPC V65, IPC V60, IPC Dmean, and CPI Dmax. Logistic regression model showed that IPC V65 > 30%, IPC V60 > 60%, IPC Dmean > 60 Gy, and CPI Dmax > 62 Gy predicted for greater than 50% probability of prolonged GT dependence. Our analysis suggests that adhering to the following parameters may decrease the risk of prolonged GT dependence and dysphagia: IPC V65 < 15%, IPC V60 < 40%, IPC Dmean < 55 Gy, and CPI Dmax < 60 Gy

  11. Analysis of oral cancer treated by preoperative radiotherapy

    International Nuclear Information System (INIS)

    Hosokawa, Yoichiro; Kaneko, Masayuki; Yasuda, Motoaki

    1997-01-01

    Fifty-eight patients with squamous cell carcinoma of the oral region, treated by preoperative radiotherapy between January 1988 and December 1993, were reviewed to evaluate the relation between prognosis and pathological findings after preoperative radiotherapy. All patients underwent external radiotherapy of up to 40 Gy in 16 fractions (2.5 Gy a day, 4 fractions a week) before surgery, and the average term from the end of preoperative radiotherapy to surgery were 27.3 days. According to pathological findings during surgery, the patients were divided into a radiation effective group and a radiation noneffective group. There was a significant difference in the survival rates of the two groups, but there was no difference in local control rates. After surgery, regional lymph node metastasis and distant metastasis were more common in the radiation noneffective group than in the radiation effective group. It was considered that regional lymph node metastasis after treatment in the noneffective group is the determining factor in the progress. (author)

  12. Conventional patient specific IMRT QA and 3DVH verification of dose distribution for helical tomotherapy

    International Nuclear Information System (INIS)

    Sharma, Prabhat Krishna; Joshi, Kishore; Epili, D.; Gavake, Umesh; Paul, Siji; Reena, Ph.; Jamema, S.V.

    2016-01-01

    In recent years, patient-specific IMRT QA has transitioned from point dose measurements by ion chambers to films to 2D array measurements. 3DVH software has taken this transition a step further by estimating the 3D dose delivered to the patient volume from 2D diode measurements using a planned dose perturbation (PDP) algorithm. This algorithm was developed to determine, if the conventional IMRT QA though sensitive at detecting errors, has any predictive power in detecting dose errors of clinical significance related to dose to the target volume and organs at risk (OAR). The aim of this study is to compare the conventional IMRT patient specific QA and 3DVH dose distribution for patients treated with helical tomotherapy (HT)

  13. Incorporating big data into treatment plan evaluation: Development of statistical DVH metrics and visualization dashboards

    Directory of Open Access Journals (Sweden)

    Charles S. Mayo, PhD

    2017-07-01

    Conclusions: Statistical DVH offers an easy-to-read, detailed, and comprehensive way to visualize the quantitative comparison with historical experiences and among institutions. WES and GEM metrics offer a flexible means of incorporating discrete threshold-prioritizations and historic context into a set of standardized scoring metrics. Together, they provide a practical approach for incorporating big data into clinical practice for treatment plan evaluations.

  14. A comparison of radiotherapy with radiotherapy plus surgery for brain metastases from urinary bladder cancer. Analysis of 62 patients

    Energy Technology Data Exchange (ETDEWEB)

    Engenhart-Cabillic, Rita [Dept. of Radiotherapy and Radiation Oncology, Philipps Univ. Marburg (Germany); Fokas, Emmanouil; Henzel, Martin

    2010-10-15

    Purpose: To evaluate the role of radiotherapy (RT) and prognostic factors in 62 patients with brain metastases from transitional cell carcinoma (TCC) of the urinary bladder. Patients and Methods: 62 patients received either RT (n = 49), including whole-brain radiotherapy (WBRT) and/or stereotactic radiosurgery (SRS), or surgery (OP) combined with WBRT (n = 13). Overall survival (OS), intracerebral control (ICC) and local control (LC) were retrospectively analyzed. Six potential prognostic factors were assessed: age, gender, number of brain metastases, extracerebral metastases, recursive partitioning analysis (RPA) class, and interval from tumor diagnosis to RT. Results: Median OS and ICC for the entire cohort were 9 and 7 months. No significant difference between RT and OP + RT was found for OS (p = 0.696) and ICC (p = 0.996). On multivariate analysis, improved OS was associated with lack of extracerebral metastases (p < 0.001) and RPA class (p < 0.001), and ICC with the latter (p < 0.001). SRS-incorporating RT resulted in 1-, 2-, and 3-year LC probability of 78%, 66%, and 51%. No association between LC and any of the potential prognostic factors was observed. The results of the subgroup RPA class analyses were similar to the entire cohort. Conclusion: Patient outcome for the RT-alone arm was not significantly different from OP + RT. SRS-incorporating treatment offers excellent LC rates. RPA class and the presence of extracerebral metastases demonstrated a significant prognostic role for survival. The latter should be used as stratification factors in randomized trials and can help define the cohort of patients that may benefit from more aggressive therapies. (orig.)

  15. Effects of Radiotherapy in the treatment of multiple myeloma: a retrospective analysis of a Single Institution

    International Nuclear Information System (INIS)

    Matuschek, Christiane; Ochtrop, Thomas A; Bölke, Edwin; Ganswindt, Ute; Fenk, Roland; Gripp, Stephan; Kröpil, Patric; Gerber, Peter Arne; Kammers, Kai; Hamilton, Jackson; Orth, Klaus; Budach, Wilfried

    2015-01-01

    Palliative irradiation of osteolytic lesions is a considerable component in the treatment for patients with multiple myeloma. In this study, we analyzed the efficacy of irradiation in these patients. We retrospectively analyzed 153 patients with multiple myeloma who were admitted to our department between 1989 and 2013. According to the staging system of Durie & Salmon 116 patients were classified as stage III. 107/153 patients were treated with radiotherapy of at least one and up to 6 bony lesions at different times. In order to evaluate the effect of local radiotherapy on pain relief and bone recalcification a uni- and multivariate analysis was performed using a binary logistic regression model to correct for multiple measurements. Complete information on dose, fractionation and volume of radiotherapy was available from 81 patients treated in 136 target volumes for pain relief, and from 69 patients treated in 108 target volumes for recalcification. Total radiation doses varied between 8 Gy to 50 Gy (median dose 25 Gy in 2.5 Gy fractions, 5 times a week). Radiotherapy resulted in complete local pain relief in 31% and partial local pain relief in 54% of the patients. In the univariate analysis, higher total radiation doses (p = 0.023) and higher age (p = 0.014) at the time of radiotherapy were significantly associated with a higher likelihood of pain relief, whereas no significant association was detected for concurrent systemic treatment, type and stage of myeloma and location of bone lesions. The same variables were independent predictors for pain relief in the multivariate analysis. Recalcification was observed in 48% of irradiated bone lesions. In the uni- and multivariate analysis higher radiation doses were significantly associated (p = 0.048) with an increased likelihood of recalcification. Side effects of radiotherapy were generally mild. Higher total biological radiation doses were associated with better pain relief and recalcification in this

  16. Analysis of radiotherapy in Kumamoto National Hospital, 3

    International Nuclear Information System (INIS)

    Fujimura, Noriharu; Shinzato, Jintetsu; Okabe, Masato; Namikawa, Kazuo; Taki, Tatsuyoshi; Kawamura, Ryoki

    1987-01-01

    Cure of esophageal carcinoma by irradiation is difficult and long-term survival rates are not yet satisfactory. A total of 119 patients with esophageal carcinoma were treated by external radiotherapy at Kumamoto National Hospital from 1968 to 1985. Forty-eight patients (40 %) were irradiated curatively with doses of more than 50 Gy and 40 patients (34 %) were irradiated palliatively. Thirty-one patients (26 %) were treated with irradiation and surgery ; 16 patients of them were treated by pre- and post-operative irradiation, 13 of them were treated by preoperative irradiation only and 2 of them were treated by postoperative irradiation. Double primary malignancy were observed in 7 cases (6 %) during the course. Cumulative survival rate of curatively irradiated patients were 27 % for 1 year, 6 % for 2 years, and 6 % for 5 years. Cumulative survival rate of combined treatment with surgery were 52 % for 1 year, 14 % for 2 years, 7 % for 3 years, and 7 % for 5 years. Fifty percent survival period in curatively irradiated patients was 7 months, but it was 13 months when the length of tumor was less than 5 cm. In our series, there were no differences in long-term survival between curatively irradiated patients and combined treatment with surgery. In the area of radiotherapy, an effort to improve irradiation method has been remarkable, but the importance of combined treatment of surgery, chemotherapy, and irradiation should be emphasized for esophageal carcinoma. (author)

  17. Transitioning from conventional radiotherapy to intensity-modulated radiotherapy for localized prostate cancer. Changing focus from rectal bleeding to detailed quality of life analysis

    International Nuclear Information System (INIS)

    Yamazaki, Hideya; Nakamura, Satoaki; Nishimura, Takuya; Yoshida, Ken; Yoshioka, Yasuo; Koizumi, Masahiko; Ogawa, Kazuhiko

    2014-01-01

    With the advent of modern radiation techniques, we have been able to deliver a higher prescribed radiotherapy dose for localized prostate cancer without severe adverse reactions. We reviewed and analyzed the change of toxicity profiles of external beam radiation therapy (EBRT) from the literature. Late rectal bleeding is the main adverse effect, and an incidence of >20% of Grade ≥2 adverse events was reported for 2D conventional radiotherapy of up to 70 Gy. 3D conformal radiation therapy (3D-CRT) was found to reduce the incidence to ∼10%. Furthermore, intensity-modulated radiation therapy (IMRT) reduced it further to a few percentage points. However, simultaneously, urological toxicities were enhanced by dose escalation using highly precise external radiotherapy. We should pay more attention to detailed quality of life (QOL) analysis, not only with respect to rectal bleeding but also other specific symptoms (such as urinary incontinence and impotence), for two reasons: (1) because of the increasing number of patients aged >80 years, and (2) because of improved survival with elevated doses of radiotherapy and/or hormonal therapy; age is an important prognostic factor not only for prostate-specific antigen (PSA) control but also for adverse reactions. Those factors shift the main focus of treatment purpose from survival and avoidance of PSA failure to maintaining good QOL, particularly in older patients. In conclusion, the focus of toxicity analysis after radiotherapy for prostate cancer patients is changing from rectal bleeding to total elaborate quality of life assessment. (author)

  18. A DICOM based radiotherapy plan database for research collaboration and reporting

    International Nuclear Information System (INIS)

    Westberg, J; Krogh, S; Brink, C; Vogelius, I R

    2014-01-01

    Purpose: To create a central radiotherapy (RT) plan database for dose analysis and reporting, capable of calculating and presenting statistics on user defined patient groups. The goal is to facilitate multi-center research studies with easy and secure access to RT plans and statistics on protocol compliance. Methods: RT institutions are able to send data to the central database using DICOM communications on a secure computer network. The central system is composed of a number of DICOM servers, an SQL database and in-house developed software services to process the incoming data. A web site within the secure network allows the user to manage their submitted data. Results: The RT plan database has been developed in Microsoft .NET and users are able to send DICOM data between RT centers in Denmark. Dose-volume histogram (DVH) calculations performed by the system are comparable to those of conventional RT software. A permission system was implemented to ensure access control and easy, yet secure, data sharing across centers. The reports contain DVH statistics for structures in user defined patient groups. The system currently contains over 2200 patients in 14 collaborations. Conclusions: A central RT plan repository for use in multi-center trials and quality assurance was created. The system provides an attractive alternative to dummy runs by enabling continuous monitoring of protocol conformity and plan metrics in a trial.

  19. A DICOM based radiotherapy plan database for research collaboration and reporting

    Science.gov (United States)

    Westberg, J.; Krogh, S.; Brink, C.; Vogelius, I. R.

    2014-03-01

    Purpose: To create a central radiotherapy (RT) plan database for dose analysis and reporting, capable of calculating and presenting statistics on user defined patient groups. The goal is to facilitate multi-center research studies with easy and secure access to RT plans and statistics on protocol compliance. Methods: RT institutions are able to send data to the central database using DICOM communications on a secure computer network. The central system is composed of a number of DICOM servers, an SQL database and in-house developed software services to process the incoming data. A web site within the secure network allows the user to manage their submitted data. Results: The RT plan database has been developed in Microsoft .NET and users are able to send DICOM data between RT centers in Denmark. Dose-volume histogram (DVH) calculations performed by the system are comparable to those of conventional RT software. A permission system was implemented to ensure access control and easy, yet secure, data sharing across centers. The reports contain DVH statistics for structures in user defined patient groups. The system currently contains over 2200 patients in 14 collaborations. Conclusions: A central RT plan repository for use in multi-center trials and quality assurance was created. The system provides an attractive alternative to dummy runs by enabling continuous monitoring of protocol conformity and plan metrics in a trial.

  20. Dosimetry, clinical factors and medication intake influencing urinary symptoms after prostate radiotherapy: An analysis of data from the RADAR prostate radiotherapy trial

    International Nuclear Information System (INIS)

    Yahya, Noorazrul; Ebert, Martin A.; Bulsara, Max; Haworth, Annette; Kennedy, Angel; Joseph, David J.; Denham, Jim W.

    2015-01-01

    Purpose/objective: To identify dosimetry, clinical factors and medication intake impacting urinary symptoms after prostate radiotherapy. Material and methods: Data describing clinical factors and bladder dosimetry (reduced with principal component (PC) analysis) for 754 patients treated with external beam radiotherapy accrued by TROG 03.04 RADAR prostate radiotherapy trial were available for analysis. Urinary symptoms (frequency, incontinence, dysuria and haematuria) were prospectively assessed using LENT-SOMA to a median of 72 months. The endpoints assessed were prevalence (grade ⩾1) at the end of radiotherapy (representing acute symptoms), at 18-, 36- and 54-month follow-ups (representing late symptoms) and peak late incidence including only grade ⩾2. Impact of factors was assessed using multivariate logistic regression models with correction for over-optimism. Results: Baseline symptoms, non-insulin dependent diabetes mellitus, age and PC1 (correlated to the mean dose) impact symptoms at >1 timepoints. Associations at a single timepoint were found for cerebrovascular condition, ECOG status and non-steroidal anti-inflammatory drug intake. Peak incidence analysis shows the impact of baseline, bowel and cerebrovascular condition and smoking status. Conclusions: The prevalence and incidence analysis provide a complementary view for urinary symptom prediction. Sustained impacts across time points were found for several factors while some associations were not repeated at different time points suggesting poorer or transient impact

  1. CT images and radiotherapy treatment planning of patients with breast cancer: A dataset

    Directory of Open Access Journals (Sweden)

    Mohammad Rezaei

    2017-08-01

    Full Text Available The data presented here were originally collected for the research project “CT-Scan processing and analysis in patient with breast cancer after radiotherapy”. Also, it reported in our study “Prediction of Lung Tissue Damage by Evaluating Clinical and Dosimetric Parameters in Breast Cancer Patients” (Hasanabdali et al., 2016 [1]. This article describes and directly links to 52 subjects referred to Mahdieh Oncology and Radiotherapy Center from February to August 2015. Treatment planning was done for delivering 50 Gy dose to PTV in 25 fractions. the lungs and heart objects were extracted from CT images along with compliance Dose plan. Dose-volume histogram (DVH and Dose-mass histogram (DMH extracted using CT images and dose plan matrix. Moreover, the complete clinical and dosimetric specifications of subjects is attached.

  2. SU-F-T-243: Major Risks in Radiotherapy. A Review Based On Risk Analysis Literature

    Energy Technology Data Exchange (ETDEWEB)

    López-Tarjuelo, J; Guasp-Tortajada, M; Iglesias-Montenegro, N; Monasor-Denia, P [Servicio de Radiofísica y Protección Radiológica, Consorcio Hospitalario Provincial de Castellón, Castellón de la Plana, España/Spain (Spain); Bouché-Babiloni, A; Morillo-Macías, V; Ferrer-Albiach, C [Servicio de Oncología Radioterápica, Consorcio Hospitalario Provincial de Castellón, Castellón de la Plana, España/Spain (Spain)

    2016-06-15

    Purpose: We present a literature review of risk analyses in radiotherapy to highlight the most reported risks and facilitate the spread of this valuable information so that professionals can be aware of these major threats before performing their own studies. Methods: We considered studies with at least an estimation of the probability of occurrence of an adverse event (O) and its associated severity (S). They cover external beam radiotherapy, brachytherapy, intraoperative radiotherapy, and stereotactic techniques. We selected only the works containing a detailed ranked series of elements or failure modes and focused on the first fully reported quartile as much. Afterward, we sorted the risk elements according to a regular radiotherapy procedure so that the resulting groups were cited in several works and be ranked in this way. Results: 29 references published between 2007 and February 2016 were studied. Publication trend has been generally rising. The most employed analysis has been the Failure mode and effect analysis (FMEA). Among references, we selected 20 works listing 258 ranked risk elements. They were sorted into 31 groups appearing at least in two different works. 11 groups appeared in at least 5 references and 5 groups did it in 7 or more papers. These last sets of risks where choosing another set of images or plan for planning or treating, errors related with contours, errors in patient positioning for treatment, human mistakes when programming treatments, and planning errors. Conclusion: There is a sufficient amount and variety of references for identifying which failure modes or elements should be addressed in a radiotherapy department before attempting a specific analysis. FMEA prevailed, but other studies such as “risk matrix” or “occurrence × severity” analyses can also lead professionals’ efforts. Risk associated with human actions ranks very high; therefore, they should be automated or at least peer-reviewed.

  3. SU-F-T-243: Major Risks in Radiotherapy. A Review Based On Risk Analysis Literature

    International Nuclear Information System (INIS)

    López-Tarjuelo, J; Guasp-Tortajada, M; Iglesias-Montenegro, N; Monasor-Denia, P; Bouché-Babiloni, A; Morillo-Macías, V; Ferrer-Albiach, C

    2016-01-01

    Purpose: We present a literature review of risk analyses in radiotherapy to highlight the most reported risks and facilitate the spread of this valuable information so that professionals can be aware of these major threats before performing their own studies. Methods: We considered studies with at least an estimation of the probability of occurrence of an adverse event (O) and its associated severity (S). They cover external beam radiotherapy, brachytherapy, intraoperative radiotherapy, and stereotactic techniques. We selected only the works containing a detailed ranked series of elements or failure modes and focused on the first fully reported quartile as much. Afterward, we sorted the risk elements according to a regular radiotherapy procedure so that the resulting groups were cited in several works and be ranked in this way. Results: 29 references published between 2007 and February 2016 were studied. Publication trend has been generally rising. The most employed analysis has been the Failure mode and effect analysis (FMEA). Among references, we selected 20 works listing 258 ranked risk elements. They were sorted into 31 groups appearing at least in two different works. 11 groups appeared in at least 5 references and 5 groups did it in 7 or more papers. These last sets of risks where choosing another set of images or plan for planning or treating, errors related with contours, errors in patient positioning for treatment, human mistakes when programming treatments, and planning errors. Conclusion: There is a sufficient amount and variety of references for identifying which failure modes or elements should be addressed in a radiotherapy department before attempting a specific analysis. FMEA prevailed, but other studies such as “risk matrix” or “occurrence × severity” analyses can also lead professionals’ efforts. Risk associated with human actions ranks very high; therefore, they should be automated or at least peer-reviewed.

  4. The surgical treatment of failure in cervical lymph nodes after radiotherapy for nasopharyngeal carcinoma: an analysis of 83 patients

    International Nuclear Information System (INIS)

    Gu Wendong; Ji Qinghai; Lu Xueguan; Feng Yan

    2003-01-01

    Objective: To analyze the results of neck dissection in patients who failed in cervical lymph nodes after radiotherapy for nasopharyngeal carcinoma. Methods: Eighty-three patients who received neck dissection due to lymph node persistence or recurrence after definitive radiotherapy were analyzed retrospectively according to the following relevant factors: age, sex, the interval between completion of radiotherapy and surgery, rN stage, postoperative radiotherapy given or not, the adjacent tissues involved or not and the number of positive nodes. Kaplan-Meier method, Log-rank method and Cox method were used in the statistical analysis. Results: The 1-, 3- and 5-year overall survival rates were 80.7%, 47.1% and 34.9%. The interval between completion of radiotherapy and surgery, postoperative radiotherapy given or not, the adjacent tissues involved or not were significantly prognostic factors in statistic analysis. Conclusions: Neck dissection can be applied in the management of cervical lymph node failure in nasopharyngeal carcinoma after radiotherapy. Postoperative radiotherapy should be considered in patients with capsular invasion and/or adjacent tissue involvement

  5. Effect of radiation in radiotherapy

    International Nuclear Information System (INIS)

    Hirata, Hideki; Fujibuchi, Toshio; Saito, Tsutomu

    2013-01-01

    The title subject is easily explained for the deterministic effect, secondary cancer formation and case reports of accidental exposure at radiotherapy. For the deterministic effect, the dose-effect relationship is sigmoidal in normal and cancer tissues, and the more separated are their curves, the more favorable is the radiotherapy. TD 5/5 is the tolerable dose to yield <5% of irreversible radiation injury to the normal tissue within 5 years after the therapy and is generally dose-limiting. The curves are of various shapes depending on the tissue composition that its functional subunit (FSU) is parallel like lobules of the liver, or in series like neuron. Symptoms appear complicated on these factors. Recent development of CT-based therapeutic planning has made it possible to analyze the partial tissue volume to be irradiated and its absorbed dose by the relationship (dose volume histogram, DVH) between the electron density vs CT value regardless to anatomy. The normal tissue complication probability is a model composed from the physical DVH and biological factors of FSU composition and cellular radiation susceptibility, and is a measure of the irreversible late effect manifested in normal tissues. Epidemiology has shown the increased risk of secondary cancer formation by radiotherapy. Children are highly susceptible to this, and in adults undergoing the therapy of a certain cancer, it is known that the risk of radiation carcinogenesis is increased in the particular tissue. There are presented such case reports of accidental excessive exposure at radiotherapy as caused by an inappropriate use of detector, partial loss of data in a therapeutic planning device, reading of reversed MRI image, and too much repeated use of the old-type electric portal imaging device. (T.T.)

  6. Radiotherapy and breast reconstruction: a meta-analysis.

    LENUS (Irish Health Repository)

    Barry, M

    2011-05-01

    The optimum sequencing of breast reconstruction (BR) in patients receiving postmastectomy radiation therapy (PMRT) is controversial. A comprehensive search of published studies that examined postoperative morbidity following immediate or delayed BR with combined radiotherapy was performed. Medical (MEDLINE & EMBASE) databases were searched and cross-referenced for appropriate studies where morbidity following BR was the primary outcome measured. A total of 1,105 patients were identified from 11 appropriately selected studies. Patients undergoing PMRT and BR are more likely to suffer morbidity compared with patients not receiving PMRT (OR = 4.2; 95% CI, 2.4-7.2 [no PMRT vs. PMRT]). Reconstruction technique was also examined with outcome when PMRT was delivered after BR, and this demonstrated that autologous reconstruction is associated with less morbidity in this setting (OR = 0.21; 95% CI, 0.1-0.4 [autologous vs. implant-based]). Delaying BR until after PMRT had no significant effect on outcome (OR = 0.87; 95% CI, 0.47-1.62 [delayed vs. immediate]). PMRT has a detrimental effect on BR outcome. These results suggest that where immediate reconstruction is undertaken with the necessity of PMRT, an autologous flap results in less morbidity when compared with implant-based reconstruction.

  7. An ill-conditioning conformal radiotherapy analysis based on singular values decomposition

    International Nuclear Information System (INIS)

    Lefkopoulos, D.; Grandjean, P.; Bendada, S.; Dominique, C.; Platoni, K.; Schlienger, M.

    1995-01-01

    Clinical experience in stereotactic radiotherapy of irregular complex lesions had shown that optimization algorithms were necessary to improve the dose distribution. We have developed a general optimization procedure which can be applied to different conformal irradiation techniques. In this presentation this procedure is tested on the stereotactic radiotherapy modality of complex cerebral lesions treated with multi-isocentric technique based on the 'associated targets methodology'. In this inverse procedure we use the singular value decomposition (SVD) analysis which proposes several optimal solutions for the narrow beams weights of each isocentre. The SVD analysis quantifies the ill-conditioning of the dosimetric calculation of the stereotactic irradiation, using the condition number which is the ratio of the bigger to smaller singular values. Our dose distribution optimization approach consists on the study of the irradiation parameters influence on the stereotactic radiotherapy inverse problem. The adjustment of the different irradiation parameters into the 'SVD optimizer' procedure is realized taking into account the ratio of the quality reconstruction to the time calculation. It will permit a more efficient use of the 'SVD optimizer' in clinical applications for real 3D lesions. The evaluation criteria for the choice of satisfactory solutions are based on the dose-volume histograms and clinical considerations. We will present the efficiency of ''SVD optimizer'' to analyze and predict the ill-conditioning in stereotactic radiotherapy and to recognize the topography of the different beams in order to create optimal reconstructed weighting vector. The planification of stereotactic treatments using the ''SVD optimizer'' is examined for mono-isocentrically and complex dual-isocentrically treated lesions. The application of the SVD optimization technique provides conformal dose distribution for complex intracranial lesions. It is a general optimization procedure

  8. Feasibility of MR-only proton dose calculations for prostate cancer radiotherapy using a commercial pseudo-CT generation method

    Science.gov (United States)

    Maspero, Matteo; van den Berg, Cornelis A. T.; Landry, Guillaume; Belka, Claus; Parodi, Katia; Seevinck, Peter R.; Raaymakers, Bas W.; Kurz, Christopher

    2017-12-01

    A magnetic resonance (MR)-only radiotherapy workflow can reduce cost, radiation exposure and uncertainties introduced by CT-MRI registration. A crucial prerequisite is generating the so called pseudo-CT (pCT) images for accurate dose calculation and planning. Many pCT generation methods have been proposed in the scope of photon radiotherapy. This work aims at verifying for the first time whether a commercially available photon-oriented pCT generation method can be employed for accurate intensity-modulated proton therapy (IMPT) dose calculation. A retrospective study was conducted on ten prostate cancer patients. For pCT generation from MR images, a commercial solution for creating bulk-assigned pCTs, called MR for Attenuation Correction (MRCAT), was employed. The assigned pseudo-Hounsfield Unit (HU) values were adapted to yield an increased agreement to the reference CT in terms of proton range. Internal air cavities were copied from the CT to minimise inter-scan differences. CT- and MRCAT-based dose calculations for opposing beam IMPT plans were compared by gamma analysis and evaluation of clinically relevant target and organ at risk dose volume histogram (DVH) parameters. The proton range in beam’s eye view (BEV) was compared using single field uniform dose (SFUD) plans. On average, a (2%, 2 mm) gamma pass rate of 98.4% was obtained using a 10% dose threshold after adaptation of the pseudo-HU values. Mean differences between CT- and MRCAT-based dose in the DVH parameters were below 1 Gy (radiotherapy, is feasible following adaptation of the assigned pseudo-HU values.

  9. Image guided radiotherapy: equipment specifications and performance - an analysis of the dosimetric consequences of anatomic variations during head-and-neck radiotherapy treatment

    International Nuclear Information System (INIS)

    Marguet, Maud

    2009-01-01

    Anatomic variations during head-and-neck radiotherapy treatment may compromise the delivery of the planned dose distribution, particularly in the case of IMRT treatments. The aim of this thesis was to establish 'dosimetric indicators' to identify patients who delivered dose deviates from the planned dose, to allow an eventual re-optimisation of the patient's dosimetry, if necessary, during the course of their radiotherapy treatment. These anatomic variations were monitored by regular acquisition of 3D patient images using an onboard imaging system, for which a rigorous quality control program was implemented. The patient dose distribution analysis and comparison was performed using a modified gamma index technique which was named gammaLSC3D. This improved gamma index technique quantified and identified the location of changes in the dose distribution in a stack of 2D images, with particular reference to the target volume (PTV) or organs at risk (parotids). The changes observed in the dose distribution for the PTV or parotids were then analysed and presented in the form of gamma-volume histograms in order to facilitate the follow up of dosimetric changes during the radiotherapy treatment. This analysis method has been automated, and is applicable in clinical routine to follow dose variations during head and neck radiotherapy treatment. (author) [fr

  10. Dosimetric Analysis of Respiratory-Gated Radiotherapy for Hepatocellular Carcinoma

    International Nuclear Information System (INIS)

    Xi Mian; Zhang Li; Liu Mengzhong; Deng Xiaowu; Huang Xiaoyan; Liu Hui

    2011-01-01

    The purpose of this study was to define individualized internal target volume (ITV) for hepatocellular carcinoma (HCC) using 4D computed tomography (4DCT), and to determine the geometric and dosimetric benefits of respiratory gating. Gross tumor volumes (GTVs) were contoured on 10 respiratory phases of 4DCT images for 12 patients with HCC. Three treatment plans were prepared using different planning target volumes (PTVs): (1) PTV 3D , derived from a single helical clinical target volume (CTV) plus conventional margins; (2) PTV 10phases , derived from ITV 10phases , which encompassed all 10 CTVs plus an isotropic margin of 0.8 cm; (3) PTV gating , derived from ITV gating , which encompassed three CTVs within gating-window at end-expiration plus an isotropic margin of 0.8 cm. The PTV 3D was the largest volume for all patients. The ITV-based plans and gating plans spared more normal tissues than 3D plans, especially the liver. Without increasing normal tissue complication probability of the 3D plans, the ITV-based plans allowed for increasing the calculated dose from 50.8 Gy to 54.7 Gy on average, and the gating plans could further escalate the dose to 58.5 Gy. Compared with ITV-based plans, the dosimetric gains with gating plan strongly correlated with GTV mobility in the craniocaudal direction. The ITV-based plans can ensure target coverage with less irradiation of normal tissues compared with 3D plans. Respiratory-gated radiotherapy can further reduce the target volumes to spare more surrounding tissues and allow dose escalation, especially for patients with tumor mobility >1 cm.

  11. Risk analysis factors for local recurrence in Ewing's sarcoma: when should adjuvant radiotherapy be administered?

    Science.gov (United States)

    Albergo, J I; Gaston, C L L; Parry, M C; Laitinen, M K; Jeys, L M; Tillman, R M; Abudu, A T; Grimer, R J

    2018-02-01

    The aim of this study was to analyse a group of patients with non-metastatic Ewing's sarcoma at presentation and identify prognostic factors affecting the development of local recurrence, in order to assess the role of radiotherapy. A retrospective review of all patients with a Ewing's sarcoma treated between 1980 and 2012 was carried out. Only those treated with chemotherapy followed by surgery and/or radiotherapy were included. Patients were grouped according to site (central or limb) for further analysis of the prognostic factors. A total of 388 patients were included in the study. Of these, 60 (15%) developed local recurrence at a mean median of 27 months (sd 24, range 7 to 150) and the five-year local recurrence-free survival (5yrLRFS) was 83%. For central tumours, the size of the tumour and histological response to chemotherapy were found to be significant factors for local recurrence. For limb tumours, local recurrence was affected by intralesional and marginal resections, but not by the histological response to chemotherapy. Radiotherapy in those with a marginal resection reduced the risk of local recurrence (5yrLRFS: 96% versus 81%, p = 0.044). Local recurrence significantly affects the overall survival in patients with a Ewing's sarcoma. For those with a tumour in a limb, radiotherapy reduced the risk of local recurrence, especially in those with a marginal margin of excision, but the effect in central tumours was less clear. Radiotherapy for those who have had a wide margin of resection does not reduce the risk of local recurrence, regardless of the histological response to chemotherapy. Cite this article: Bone Joint J 2018;100-B: 247-55. ©2018 The British Editorial Society of Bone & Joint Surgery.

  12. Simple DVH parameter addition as compared to deformable registration for bladder dose accumulation in cervix cancer brachytherapy

    DEFF Research Database (Denmark)

    Andersen, Else Stougård; Noe, Karsten Østergaaard; Sørensen, Thomas Sangild

    2013-01-01

    Background and purpose: Variations in organ position, shape, and volume cause uncertainties in dose assessment for brachytherapy (BT) in cervix cancer. The purpose of this study was to evaluate uncertainties associated with bladder dose accumulation based on DVH parameter addition (previously...... called "the worst case assumption") in fractionated BT. Materials and methods: Forty-seven patients treated for locally advanced cervical cancer were included. All patients received EBRT combined with two individually planned 3D image-guided adaptive BT fractions. D2 and D0.1 were estimated by DVH...

  13. Prediction of DVH parameter changes due to setup errors for breast cancer treatment based on 2D portal dosimetry

    International Nuclear Information System (INIS)

    Nijsten, S. M. J. J. G.; Elmpt, W. J. C. van; Mijnheer, B. J.; Minken, A. W. H.; Persoon, L. C. G. G.; Lambin, P.; Dekker, A. L. A. J.

    2009-01-01

    Electronic portal imaging devices (EPIDs) are increasingly used for portal dosimetry applications. In our department, EPIDs are clinically used for two-dimensional (2D) transit dosimetry. Predicted and measured portal dose images are compared to detect dose delivery errors caused for instance by setup errors or organ motion. The aim of this work is to develop a model to predict dose-volume histogram (DVH) changes due to setup errors during breast cancer treatment using 2D transit dosimetry. First, correlations between DVH parameter changes and 2D gamma parameters are investigated for different simulated setup errors, which are described by a binomial logistic regression model. The model calculates the probability that a DVH parameter changes more than a specific tolerance level and uses several gamma evaluation parameters for the planning target volume (PTV) projection in the EPID plane as input. Second, the predictive model is applied to clinically measured portal images. Predicted DVH parameter changes are compared to calculated DVH parameter changes using the measured setup error resulting from a dosimetric registration procedure. Statistical accuracy is investigated by using receiver operating characteristic (ROC) curves and values for the area under the curve (AUC), sensitivity, specificity, positive and negative predictive values. Changes in the mean PTV dose larger than 5%, and changes in V 90 and V 95 larger than 10% are accurately predicted based on a set of 2D gamma parameters. Most pronounced changes in the three DVH parameters are found for setup errors in the lateral-medial direction. AUC, sensitivity, specificity, and negative predictive values were between 85% and 100% while the positive predictive values were lower but still higher than 54%. Clinical predictive value is decreased due to the occurrence of patient rotations or breast deformations during treatment, but the overall reliability of the predictive model remains high. Based on our

  14. Radiotherapy in desmoid tumors. Treatment response, local control, and analysis of local failures

    Energy Technology Data Exchange (ETDEWEB)

    Santti, Kirsi; Beule, Annette; Tuomikoski, Laura; Jaeaeskelaeinen, Anna-Stina; Saarilahti, Kauko; Tarkkanen, Maija; Blomqvist, Carl [Helsinki University Hospital and University of Helsinki, Comprehensive Cancer Center, Helsinki (Finland); Roenty, Mikko [HUSLAB and University of Helsinki, Department of Pathology, Helsinki (Finland); Ihalainen, Hanna [Helsinki University Hospital and University of Helsinki, Department of Plastic Surgery, Helsinki (Finland)

    2017-04-15

    Desmoid tumors (aggressive fibromatosis) are rare soft tissue tumors which frequently recur after surgery. Desmoid tumors arise from musculoaponeurotic tissue in the extremities, head and neck, abdominal wall, or intra-abdominally. Our aim was to examine the outcome of radiotherapy of desmoid tumors in a single institution series. We evaluated 41 patients with desmoid tumors treated with 49 radiotherapies between 1987 and 2012. Radiologic images for response evaluation were reassessed and responses to treatment registered according to RECIST criteria 1.1. For patients with local failures radiation dose distribution was determined in each local failure volume using image co-registration. Recurrences were classified as in-target, marginal, or out-of-target. Prognostic factors for radiotherapy treatment failure were evaluated. Radiotherapy doses varied from 20-63 Gy (median 50 Gy) with a median fraction size of 2 Gy. The objective response rate to definitive radiotherapy was 55% (12/22 patients). Median time to response was 14 months. A statistically significant dose-response relation for definitive and postoperative radiotherapy was observed both in univariate (p-value 0.002) and in multivariate analysis (p-value 0.02) adjusted for potential confounding factors. Surgery before radiotherapy or surgical margin had no significant effect on time to progression. Nine of 11 (82%) local failures were classified as marginal and two of 11 (18%) in-target. None of the recurrences occurred totally out-of-target. Radiotherapy is a valuable option for treating desmoid tumors. Radiotherapy dose appears to be significantly associated to local control. (orig.) [German] Desmoide (aggressive Fibromatosen) sind seltene Weichteiltumore der muskulaeren Membranen von Kopf, Hals, Extremitaeten und Bauchwand. Ziel war es, die Wirksamkeit der Strahlentherapie bei aggressiver Fibromatose an einer einzelnen Klinik zu untersuchen. Ausgewertet wurden 41 Patienten mit aggressiver Fibromatose, die

  15. Non-compliance with a postmastectomy radiotherapy guideline: Decision tree and cause analysis

    OpenAIRE

    Razavi, Amir R; Gill, Hans; Åhlfeldt, Hans; Shahsavar, Nosrat

    2008-01-01

    Background: The guideline for postmastectomy radiotherapy (PMRT), which is prescribed to reduce recurrence of breast cancer in the chest wall and improve overall survival, is not always followed. Identifying and extracting important patterns of non-compliance are crucial in maintaining the quality of care in Oncology. Methods: Analysis of 759 patients with malignant breast cancer using decision tree induction (DTI) found patterns of non-compliance with the guideline. The PMRT guideline was us...

  16. Sequencing chemotherapy and radiotherapy in locoregional advanced breast cancer patients after mastectomy – a retrospective analysis

    International Nuclear Information System (INIS)

    Piroth, Marc D; Pinkawa, Michael; Gagel, Bernd; Stanzel, Sven; Asadpour, Branka; Eble, Michael J

    2008-01-01

    Combined chemo- and radiotherapy are established in breast cancer treatment. Chemotherapy is recommended prior to radiotherapy but decisive data on the optimal sequence are rare. This retrospective analysis aimed to assess the role of sequencing in patients after mastectomy because of advanced locoregional disease. A total of 212 eligible patients had a stage III breast cancer and had adjuvant chemotherapy and radiotherapy after mastectomy and axillary dissection between 1996 and 2004. According to concerted multi-modality treatment strategies 86 patients were treated sequentially (chemotherapy followed by radiotherapy) (SEQgroup), 70 patients had a sandwich treatment (SW-group) and 56 patients had simultaneous chemoradiation (SIM-group) during that time period. Radiotherapy comprised the thoracic wall and/or regional lymph nodes. The total dose was 45–50.4 Gray. As simultaneous chemoradiation CMF was given in 95.4% of patients while in sequential or sandwich application in 86% and 87.1% of patients an anthracycline-based chemotherapy was given. Concerning the parameters nodal involvement, lymphovascular invasion, extracapsular spread and extension of the irradiated region the three treatment groups were significantly imbalanced. The other parameters, e.g. age, pathological tumor stage, grading and receptor status were homogeneously distributed. Looking on those two groups with an equally effective chemotherapy (EC, FEC), the SEQ- and SW-group, the sole imbalance was the extension of LVI (57.1 vs. 25.6%, p < 0.0001). 5-year overall- and disease free survival were 53.2%/56%, 38.1%/32% and 64.2%/50%, for the sequential, sandwich and simultaneous regime, respectively, which differed significantly in the univariate analysis (p = 0.04 and p = 0.03, log-rank test). Also the 5-year locoregional or distant recurrence free survival showed no significant differences according to the sequence of chemo- and radiotherapy. In the multivariate analyses the sequence had no

  17. A novel four-dimensional radiotherapy planning strategy from a tumor-tracking beam's eye view

    Science.gov (United States)

    Li, Guang; Cohen, Patrice; Xie, Huchen; Low, Daniel; Li, Diana; Rimner, Andreas

    2012-11-01

    To investigate the feasibility of four-dimensional radiotherapy (4DRT) planning from a tumor-tracking beam's eye view (ttBEV) with reliable gross tumor volume (GTV) delineation, realistic normal tissue representation, high planning accuracy and low clinical workload, we propose and validate a novel 4D conformal planning strategy based on a synthesized 3.5D computed tomographic (3.5DCT) image with a motion-compensated tumor. To recreate patient anatomy from a ttBEV in the moving tumor coordinate system for 4DRT planning (or 4D planning), the centers of delineated GTVs in all phase CT images of 4DCT were aligned, and then the aligned CTs were averaged to produce a new 3.5DCT image. This GTV-motion-compensated CT contains a motionless target (with motion artifacts minimized) and motion-blurred normal tissues (with a realistic temporal density average). Semi-automatic threshold-based segmentation of the tumor, lung and body was applied, while manual delineation was used for other organs at risk (OARs). To validate this 3.5DCT-based 4D planning strategy, five patients with peripheral lung lesions of small size (tumor and a minor beam aperture and weighting adjustment to maintain plan conformality. The dose-volume histogram (DVH) of the 4DCT plan was created with two methods: one is an integrated DVH (iDVH4D), which is defined as the temporal average of all 3D-phase-plan DVHs, and the other (DVH4D) is based on the dose distribution in a reference phase CT image by dose warping from all phase plans using the displacement vector field (DVF) from a free-form deformable image registration (DIR). The DVH3.5D (for the 3.5DCT plan) was compared with both iDVH4D and DVH4D. To quantify the DVH difference between the 3.5DCT plan and the 4DCT plan, two methods were used: relative difference (%) of the areas underneath the DVH curves and the volumes receiving more than 20% (V20) and 50% (V50) of prescribed dose of these 4D plans. The volume of the delineated GTV from different phase

  18. SU-F-T-266: Dynalogs Based Evaluation of Different Dose Rate IMRT Using DVH and Gamma Index

    International Nuclear Information System (INIS)

    Ahmed, S; Ahmed, S; Ahmed, F; Hussain, A

    2016-01-01

    Purpose: This work investigates the impact of low and high dose rate on IMRT through Dynalogs by evaluating Gamma Index and Dose Volume Histogram. Methods: The Eclipse™ treatment planning software was used to generate plans on prostate and head and neck sites. A range of dose rates 300 MU/min and 600 MU/min were applied to each plan in order to investigate their effect on the beam ON time, efficiency and accuracy. Each plan had distinct monitor units per fraction, delivery time, mean dose rate and leaf speed. The DVH data was used in the assessment of the conformity and plan quality.The treatments were delivered on Varian™ Clinac 2100C accelerator equipped with 120 leaf millennium MLC. Dynalogs of each plan were analyzed by MATLAB™ program. Fluence measurements were performed using the Sun Nuclear™ 2D diode array and results were assessed, based on Gamma analysis of dose fluence maps, beam delivery statistics and Dynalogs data. Results: Minor differences found by adjusted R-squared analysis of DVH’s for all the plans with different dose rates. It has been also found that more and larger fields have greater time reduction at high dose rate and there was a sharp decrease in number of control points observed in dynalog files by switching dose rate from 300 MU/min to 600 MU/min. Gamma Analysis of all plans passes the confidence limit of ≥95% with greater number of passing points in 300 MU/min dose rate plans. Conclusion: The dynalog files are compatible tool for software based IMRT QA. It can work perfectly parallel to measurement based QA setup and stand-by procedure for pre and post delivery of treatment plan.

  19. SU-F-T-266: Dynalogs Based Evaluation of Different Dose Rate IMRT Using DVH and Gamma Index

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, S [Aga Khan University Hospital, Karachi, Sindh (Pakistan); Ahmed, S [Pakistan Inst of Eng Applied Sciences, Islamabad (Pakistan); Ahmed, F; Hussain, A

    2016-06-15

    Purpose: This work investigates the impact of low and high dose rate on IMRT through Dynalogs by evaluating Gamma Index and Dose Volume Histogram. Methods: The Eclipse™ treatment planning software was used to generate plans on prostate and head and neck sites. A range of dose rates 300 MU/min and 600 MU/min were applied to each plan in order to investigate their effect on the beam ON time, efficiency and accuracy. Each plan had distinct monitor units per fraction, delivery time, mean dose rate and leaf speed. The DVH data was used in the assessment of the conformity and plan quality.The treatments were delivered on Varian™ Clinac 2100C accelerator equipped with 120 leaf millennium MLC. Dynalogs of each plan were analyzed by MATLAB™ program. Fluence measurements were performed using the Sun Nuclear™ 2D diode array and results were assessed, based on Gamma analysis of dose fluence maps, beam delivery statistics and Dynalogs data. Results: Minor differences found by adjusted R-squared analysis of DVH’s for all the plans with different dose rates. It has been also found that more and larger fields have greater time reduction at high dose rate and there was a sharp decrease in number of control points observed in dynalog files by switching dose rate from 300 MU/min to 600 MU/min. Gamma Analysis of all plans passes the confidence limit of ≥95% with greater number of passing points in 300 MU/min dose rate plans. Conclusion: The dynalog files are compatible tool for software based IMRT QA. It can work perfectly parallel to measurement based QA setup and stand-by procedure for pre and post delivery of treatment plan.

  20. Impact of systematic errors on DVH parameters of different OAR and target volumes in Intracavitary Brachytherapy (ICBT)

    International Nuclear Information System (INIS)

    Mourya, Ankur; Singh, Gaganpreet; Kumar, Vivek; Oinam, Arun S.

    2016-01-01

    Aim of this study is to analyze the impact of systematic errors on DVH parameters of different OAR and Target volumes in intracavitary brachytherapy (ICBT). To quantify the changes in dose-volume histogram parameters due to systematic errors in applicator reconstruction of brachytherapy planning, known errors in catheter reconstructions have to be introduced in applicator coordinate system

  1. Principal Component Analysis-Based Pattern Analysis of Dose-Volume Histograms and Influence on Rectal Toxicity

    International Nuclear Information System (INIS)

    Soehn, Matthias; Alber, Markus; Yan Di

    2007-01-01

    Purpose: The variability of dose-volume histogram (DVH) shapes in a patient population can be quantified using principal component analysis (PCA). We applied this to rectal DVHs of prostate cancer patients and investigated the correlation of the PCA parameters with late bleeding. Methods and Materials: PCA was applied to the rectal wall DVHs of 262 patients, who had been treated with a four-field box, conformal adaptive radiotherapy technique. The correlated changes in the DVH pattern were revealed as 'eigenmodes,' which were ordered by their importance to represent data set variability. Each DVH is uniquely characterized by its principal components (PCs). The correlation of the first three PCs and chronic rectal bleeding of Grade 2 or greater was investigated with uni- and multivariate logistic regression analyses. Results: Rectal wall DVHs in four-field conformal RT can primarily be represented by the first two or three PCs, which describe ∼94% or 96% of the DVH shape variability, respectively. The first eigenmode models the total irradiated rectal volume; thus, PC1 correlates to the mean dose. Mode 2 describes the interpatient differences of the relative rectal volume in the two- or four-field overlap region. Mode 3 reveals correlations of volumes with intermediate doses (∼40-45 Gy) and volumes with doses >70 Gy; thus, PC3 is associated with the maximal dose. According to univariate logistic regression analysis, only PC2 correlated significantly with toxicity. However, multivariate logistic regression analysis with the first two or three PCs revealed an increased probability of bleeding for DVHs with more than one large PC. Conclusions: PCA can reveal the correlation structure of DVHs for a patient population as imposed by the treatment technique and provide information about its relationship to toxicity. It proves useful for augmenting normal tissue complication probability modeling approaches

  2. SU-E-J-164: Estimation of DVH Variation for PTV Due to Interfraction Organ Motion in Prostate VMAT Using Gaussian Error Function

    International Nuclear Information System (INIS)

    Lewis, C; Jiang, R; Chow, J

    2015-01-01

    Purpose: We developed a method to predict the change of DVH for PTV due to interfraction organ motion in prostate VMAT without repeating the CT scan and treatment planning. The method is based on a pre-calculated patient database with DVH curves of PTV modelled by the Gaussian error function (GEF). Methods: For a group of 30 patients with different prostate sizes, their VMAT plans were recalculated by shifting their PTVs 1 cm with 10 increments in the anterior-posterior, left-right and superior-inferior directions. The DVH curve of PTV in each replan was then fitted by the GEF to determine parameters describing the shape of curve. Information of parameters, varying with the DVH change due to prostate motion for different prostate sizes, was analyzed and stored in a database of a program written by MATLAB. Results: To predict a new DVH for PTV due to prostate interfraction motion, prostate size and shift distance with direction were input to the program. Parameters modelling the DVH for PTV were determined based on the pre-calculated patient dataset. From the new parameters, DVH curves of PTVs with and without considering the prostate motion were plotted for comparison. The program was verified with different prostate cases involving interfraction prostate shifts and replans. Conclusion: Variation of DVH for PTV in prostate VMAT can be predicted using a pre-calculated patient database with DVH curve fitting. The computing time is fast because CT rescan and replan are not required. This quick DVH estimation can help radiation staff to determine if the changed PTV coverage due to prostate shift is tolerable in the treatment. However, it should be noted that the program can only consider prostate interfraction motions along three axes, and is restricted to prostate VMAT plan using the same plan script in the treatment planning system

  3. Applying failure mode effects and criticality analysis in radiotherapy: Lessons learned and perspectives of enhancement

    International Nuclear Information System (INIS)

    Scorsetti, Marta; Signori, Chiara; Lattuada, Paola; Urso, Gaetano; Bignardi, Mario; Navarria, Pierina; Castiglioni, Simona; Mancosu, Pietro; Trucco, Paolo

    2010-01-01

    Introduction: The radiation oncology process along with its unique therapeutic properties is also potentially dangerous for the patient, and thus it should be delivered under a systematic risk control. To this aim incident reporting and analysis are not sufficient for assuring patient safety and proactive risk assessment should also be implemented. The paper accounts for some methodological solutions, lessons learned and opportunities for improvement, starting from the systematic application of the failure mode effects and criticality analysis (FMECA) technique to the radiotherapy process of an Italian hospital. Materials and methods: The analysis, performed by a working group made of experts of the radiotherapy unit, was organised into the following steps: (1) complete and detailed analysis of the process (integration definition for function modelling); (2) identification of possible failure modes (FM) of the process, representing sources of adverse events for the patient; (3) qualitative risk assessment of FMs, aimed at identifying priorities of intervention; (4) identification and planning of corrective actions. Results: Organisational and procedural corrective measures were implemented; a set of safety indexes for the process was integrated within the traditional quality assurance indicators measured by the unit. A strong commitment of all the professionals involved was observed and the study revealed to be a powerful 'tool' for dissemination of patient safety culture. Conclusion: The feasibility of FMECA in fostering radiotherapy safety was proven; nevertheless, some lessons learned as well as weaknesses of current practices in risk management open to future research for the integration of retrospective methods (e.g. incident reporting or root cause analysis) and risk assessment.

  4. 3-D conformal radiotherapy of localized prostate cancer: A subgroup analysis of rectoscopic findings prior to radiotherapy and acute/late rectal side effects

    International Nuclear Information System (INIS)

    Goldner, Gregor; Zimmermann, Frank; Feldmann, Horst; Glocker, Stefan; Wachter-Gerstner, Natascha; Geinitz, Hans; Becker, Gerd; Poetzi, Regina; Wambersie, Andre; Bamberg, Michael; Molls, Michael; Wachter, Stefan; Poetter, Richard

    2006-01-01

    Background and purpose: To identify endoscopic pathological findings prior to radiotherapy and a possible correlation with acute or chronic rectal side effects after three-dimensional conformal radiotherapy (3D-CRT) for prostate cancer. Patients and methods: Between 03/99 and 07/02, a total of 298 patients, who consented in a voluntary rectoscopy prior to radiotherapy were included into the analysis. Patients were treated with a total dose of either 70 or 74 Gy. Pathological rectoscopic findings like hemorrhoids, polyps or diverticula were documented. Acute and late rectal side effects were scored using the EORTC/RTOG score. Results: The most frequent pathological endosopic findings were hemorrhoids (35%), polyps (24%) and diverticula (13%). Rectal toxicity was mostly low to moderate. Grade 0/1 cumulative acute and late rectal side effects were 82 and 84%, grade 2 were 18 and 17%, respectively. We could not identify any correlation between preexisting pathological findings and rectal side effects by statistical analysis. Conclusions: There is no evidence that prostate cancer patients presenting with endoscopic verified pathological findings in the rectal mucosa at diagnosis are at an increased risk to develop rectal side effects when treated with 3D-CRT of the prostatic region

  5. Salvage HIFU after radiotherapy and salvage radiotherapy after HIFU in locally recurrent prostate cancer: Retrospective analysis of morbidity

    International Nuclear Information System (INIS)

    Lee, J.-W.; Hannoun-Leviac, J.-M.; Chevallier, D.; Rouscoff, Y.; Durand, M.; Amiel, J.; Gal, J.; Natale, R.; Chand, M.-E.; Raffaelli, C.; Ambrosetti, D.

    2012-01-01

    To evaluate the toxicity of therapeutic sequences High Intensity Focused Ultrasound (HIFU)-salvage radiotherapy (HIFU-RT) or radiotherapy-salvage HIFU (RT-HIFU) in case of locally recurrent prostate cancer. Nineteen patients had a local recurrence of prostate cancer. Among them, 10 patients were treated by HIFU-RT and 9 patients by RT- HIFU (4 by external beam radiotherapy [EBR] and 5 by brachytherapy [BRACHY]). Urinary side effects were assessed using CTCAE v4. At the time of the initial management, the median age was 66.5 years (53 72), the median PSA was 10.8 ng/mL (3.4 50) and the median initial Gleason score was 6.3 (5 8). Median follow-up after salvage treatment was 46.3 months (2 108). Thirty percent of the patients in the HIFU-RT group and 33.3 % of the patients in the RT-HIFU group, all belonging to the sub-group BRACHY-HIFU, had urinary complication greater than or equal to grade 2. Among all the patients, only 1 had grade 1 gastrointestinal toxicity. BRACHY-HIFU sequence seems to be purveyor of many significant urinary side effects. A larger database is needed to confirm this conclusion. (authors)

  6. Dose Volume Histogram analysis for rectum and urethral reaction of prostate cancer

    International Nuclear Information System (INIS)

    Yanagi, Takeshi; Tsuji, Hiroshi; Kamada, Tadashi; Tsujii, Hirohiko

    2005-01-01

    The aim of this study is to evaluate the clinically relevant parameters for rectum and urethral reaction using DVH (dose volume histogram) in carbon ion radiotherapy of prostate cancer. In this year, we studied the urinary reaction mainly. 35 patients with prostate cancer were treated with carbon ion beams between June 1995 and December 1997. The applied dose was escalated from 54.0 GyE to 72.0 GyE in fixed 20 fractions. Clinical urinary reaction and rectum reaction were reviewed using Radiation Therapy Oncology Group (RTOG) scoring system for acute reactions, RTOG/European Organization for Research and Treatment of Cancer (EORTC) scoring system for late reactions. Taking the ROI (region of interest) for DVH of urethra, we used surrogate one that was derived from the observation of MR images. 35 patients were analyzed for acute urinary reaction and 34 for late urinary reaction in the study of this year. DVH analysis suggested difference among the grades for acute and late reactions. These analysis appears to be a useful tool for predicting the urinary reactions. (author)

  7. Therapeutic effect analysis of three dimensional conformal radiotherapy non-small cell lung cancer

    International Nuclear Information System (INIS)

    Yao Zhijun; Cao Yongzhen; Zhang Wenxue; Liang Feng

    2012-01-01

    Objective: To analyse the treatment effect of non-small cell lung cancer of three dimensional conformal radiotherapy (3D-CRT) and to study the effect of patient survival related factors. Methods: Retrospective analysis was mack for 136 cases of non-small cell lung cancer, all accept 3D-CRT, through the case data collection and long-term follow-up, using the single factor and multiple factor analysis survival time and its influencing factors. Results: The recent curative effects of 136 cases of patients with three dimensional conformal radiotherapy: Complete response (CR) 14.7% (20/136), partial response (PR) 60.3 (82/136), stable disease(SD) 19.9% (27/136), progression disease (PD) 5.1% (7/136), total effective rate is 75% (102/136). One, two, three, five year survival rate is 79.4%, 45.4%, 22.1%, 12.5%. Side effects: Class 1 radiated esophagitis 35 cases, Class 2 radiated esophagitis 16 cases, Class 3 and above radiated esophagitis 0 case. Class I radiated pneumonia 20 cases, Class 2 radiated pneumonia 9 cases, Class 3 radiated pneumonia 0 case. Single factor analysis shows the influence of gender, age, pathology, phase, dose, and first-phase curative effect to the survival time are of a statistical significance, Multiple factor analysis showed KPS score, phase, dose, first-phase curative effect are the survival time independent factors. Conclusion: 3D-CRT for patients with non-small cell lung carcinoma is a safe, effective treatment method, Side effects are relatively low, and the patients survival time is long after radiotherapy. (authors)

  8. Analysis of locally controlled esophageal carcinomas treated with radiotherapy

    International Nuclear Information System (INIS)

    Gotoh, Yasuo; Yamada, Shogo; Takai, Yoshihiro; Nemoto, Kenji; Ogawa, Yoshihiro; Hoshi, Akihiko; Ariga, Hisanori; Sakamoto, Kiyohiko

    1996-01-01

    Of 227 esophageal carcinomas treated with a radiation dose of 60 Gy or more, 100 patients had no tumor or ulceration (with or without stenosis) of the esophagus after irradiation. We analyzed local control factors of these 100 patients to determine the need for further treatment. The cumulative local control rate at five years was 40% in all cases, 37% in 21 cases without any stenosis of the esophagus and 40% in 79 cases with stenosis. The presence of stenosis of the esophagus after irradiation was not a critical factor in predicting final local control. Local recurrence of tumors with findings of Borrmann III or Borrmann IV by the pretreatment esophageal barium study, tumors controlled after a total dose of more than 80 Gy, tumors without low dose rate telecobalt therapy (LDRT: 1 Gy/hour, 5 to 7 Gy/day, a total dose of 12 to 15 Gy) as boost therapy, and apparently controlled tumors with a stenotic ratio of 60% or more or with 5 cm or more length of stenosis of the esophagus after irradiation was significantly higher than that of the others (p<0.05). Multivariate analysis revealed that findings of pretreatment barium study, total dose, with or without LDRT, and length of stenosis of the esophagus after irradiation were significantly important factors in local control. Members of the high risk group of apparently controlled tumors should undertake surgical treatment or further intensive chemotherapy. (author)

  9. SU-F-T-245: The Investigation of Failure Mode and Effects Analysis and PDCA for the Radiotherapy Risk Reduction

    International Nuclear Information System (INIS)

    Xie, J; Wang, J; P, J; Chen, J; Hu, W

    2016-01-01

    Purpose: To optimize the clinical processes of radiotherapy and to reduce the radiotherapy risks by implementing the powerful risk management tools of failure mode and effects analysis(FMEA) and PDCA(plan-do-check-act). Methods: A multidiciplinary QA(Quality Assurance) team from our department consisting of oncologists, physicists, dosimetrists, therapists and administrator was established and an entire workflow QA process management using FMEA and PDCA tools was implemented for the whole treatment process. After the primary process tree was created, the failure modes and Risk priority numbers(RPNs) were determined by each member, and then the RPNs were averaged after team discussion. Results: 3 of 9 failure modes with RPN above 100 in the practice were identified in the first PDCA cycle, which were further analyzed to investigate the RPNs: including of patient registration error, prescription error and treating wrong patient. New process controls reduced the occurrence, or detectability scores from the top 3 failure modes. Two important corrective actions reduced the highest RPNs from 300 to 50, and the error rate of radiotherapy decreased remarkably. Conclusion: FMEA and PDCA are helpful in identifying potential problems in the radiotherapy process, which was proven to improve the safety, quality and efficiency of radiation therapy in our department. The implementation of the FMEA approach may improve the understanding of the overall process of radiotherapy while may identify potential flaws in the whole process. Further more, repeating the PDCA cycle can bring us closer to the goal: higher safety and accuracy radiotherapy.

  10. SU-F-T-245: The Investigation of Failure Mode and Effects Analysis and PDCA for the Radiotherapy Risk Reduction

    Energy Technology Data Exchange (ETDEWEB)

    Xie, J; Wang, J; P, J; Chen, J; Hu, W [Fudan University Shanghai Cancer Center, Shanghai, Shanghai (China)

    2016-06-15

    Purpose: To optimize the clinical processes of radiotherapy and to reduce the radiotherapy risks by implementing the powerful risk management tools of failure mode and effects analysis(FMEA) and PDCA(plan-do-check-act). Methods: A multidiciplinary QA(Quality Assurance) team from our department consisting of oncologists, physicists, dosimetrists, therapists and administrator was established and an entire workflow QA process management using FMEA and PDCA tools was implemented for the whole treatment process. After the primary process tree was created, the failure modes and Risk priority numbers(RPNs) were determined by each member, and then the RPNs were averaged after team discussion. Results: 3 of 9 failure modes with RPN above 100 in the practice were identified in the first PDCA cycle, which were further analyzed to investigate the RPNs: including of patient registration error, prescription error and treating wrong patient. New process controls reduced the occurrence, or detectability scores from the top 3 failure modes. Two important corrective actions reduced the highest RPNs from 300 to 50, and the error rate of radiotherapy decreased remarkably. Conclusion: FMEA and PDCA are helpful in identifying potential problems in the radiotherapy process, which was proven to improve the safety, quality and efficiency of radiation therapy in our department. The implementation of the FMEA approach may improve the understanding of the overall process of radiotherapy while may identify potential flaws in the whole process. Further more, repeating the PDCA cycle can bring us closer to the goal: higher safety and accuracy radiotherapy.

  11. Automatic analysis of image quality control for Image Guided Radiation Therapy (IGRT) devices in external radiotherapy

    International Nuclear Information System (INIS)

    Torfeh, Tarraf

    2009-01-01

    On-board imagers mounted on a radiotherapy treatment machine are very effective devices that improve the geometric accuracy of radiation delivery. However, a precise and regular quality control program is required in order to achieve this objective. Our purpose consisted of developing software tools dedicated to an automatic image quality control of IGRT devices used in external radiotherapy: 2D-MV mode for measuring patient position during the treatment using high energy images, 2D-kV mode (low energy images) and 3D Cone Beam Computed Tomography (CBCT) MV or kV mode, used for patient positioning before treatment. Automated analysis of the Winston and Lutz test was also proposed. This test is used for the evaluation of the mechanical aspects of treatment machines on which additional constraints are carried out due to the on-board imagers additional weights. Finally, a technique of generating digital phantoms in order to assess the performance of the proposed software tools is described. Software tools dedicated to an automatic quality control of IGRT devices allow reducing by a factor of 100 the time spent by the medical physics team to analyze the results of controls while improving their accuracy by using objective and reproducible analysis and offering traceability through generating automatic monitoring reports and statistical studies. (author) [fr

  12. A Qualitative Analysis of Acute Skin Toxicity among Breast Cancer Radiotherapy Patients

    Science.gov (United States)

    Schnur, Julie B.; Ouellette, Suzanne C.; DiLorenzo, Terry A.; Green, Sheryl; Montgomery, Guy H.

    2013-01-01

    Objectives One of the most common acute side effects of breast cancer radiotherapy is treatment induced skin changes, referred to as skin toxicity. Yet no research to date has focused expressly on skin toxicity-related quality of life in breast cancer radiotherapy patients. Therefore, our aim was to use qualitative approaches to better understand the impact of skin toxicity on quality of life. Methods Semi-structured interviews were conducted with 20 women (Stage 0-III breast cancer), during their last week of external beam radiotherapy. Each interview was transcribed verbatim, and thematic analysis was performed. Results Three themes were identified based on the interview responses: First, skin changes affect multiple dimensions of quality of life. They cause physical discomfort, body image disturbance, emotional distress, and impair both day-to-day functioning and satisfaction with radiation treatment. Second, individual differences affect women’s experiences. Generally African-American women, younger women, women who are not currently in a relationship, women who are being treated during the summer, and women who are more invested in their appearance are more distressed by skin toxicity. Third, women use a variety of symptom management strategies including self-medication, complementary/alternative medicine approaches, and psychological strategies. Conclusions Implications of results are: 1) Skin toxicity affects numerous dimensions of quality of life, and assessment approaches and psychosocial interventions should address this; 2) individual differences may affect the experience of skin toxicity, and should be considered in treatment and education approaches; and 3) participants’ own creativity and problem-solving should be used to improve the treatment experience. PMID:20238306

  13. The contribution of ergonomic analysis to the improvement of working conditions, patient reception, and quality in radiotherapy

    International Nuclear Information System (INIS)

    Estryn-Behar, M.; Bougniot, C.; Colleu, C.; Launec, V.; Lepinay, S.; Pihery, M.; Bauden, F.; Stambouli, A.; Maylin, C.

    2000-01-01

    The authors report an ergonomic analysis of the activity in a radiotherapy department of a hospital. This study aimed at understanding physiological fatigue and pathologies among technical personnel, at analyzing factors which impact reception quality, but also the professional satisfaction associated with this profession. The authors have developed a guide for a radiotherapy technician workstation study. They report and comment the activity analysis (time organisation, working time in different positions, movements and handling, handled weights), also outline the anxiety associated with the risk of mistake. They identify various improvement possibilities

  14. Postoperative radiotherapy for endometrial carcinoma. A retrospective analysis of 541 cases

    International Nuclear Information System (INIS)

    Haensgen, G.; Nagel, M.; Dunst, J.; Enke, H.

    1999-01-01

    Purpose: This retrospective study was designed to evaluate the role of adjuvant radiotherapy for surgically treated endometrial carcinoma. Patients and methods: From 1980 through 1988, 541 patients were treated with either intravaginal cuff irradiation with a high-dose-rate (HDR) Iridium-192 remote afterloading technique (n=294) or with combined HDR-brachytherapy and additional external pelvic irradiation to 54 Gy (n=247) after surgery for endometrical cancer. Afterloading irradiation was administered in 4 fractions 4 to 6 weeks after surgery. A dose of 30 Gy was delivered at a depth of 0,5 cm from the vaginal mucosa. Results: Patients with HDR-brachytherapy alone showed a 5-year survival of 94.3% for Stage I and 73.6% for Stage II (p=0.0007). Patients who received both brachytherapy and additional pelvic irradiation had a 5-year survival of 94.1% for Stage I, 81.1% for Stage II, 70.4% for Stage III and 46.9% for Stage IV (p=0.0001). The main predictors for survival in a multivariate analysis were stage and grading. Patients with combined readiotherapy had a local recurrence rate of 3.2%, whereas patients with brachytherapy alone who were better selected and had more favorable prognostic factors showed a recurrence rate of 2%. Low-risk patients (Stage I, Grade 1, low infiltration) in the HDR-brachytherapy group had 6 relapses, mainly caused by insufficient treatment on the basis of papillary histology. High-risk patients with poorly differential tumors, which infiltrate more than half the myometrial wall might benefit from additional external radiotherapy in terms of reduction of local recurrence and better survival. Five-year actuarial survival rate was 93.6% after combined radiotherapy vs 86.7% after brachytherapy alone. Complications were graded according to the RTOG scoring system. Severe late complications were fistulas of bladder and/or bowel, which occurred in 2.8% in the combined radiotherapy group, and 0.7% in the HDR brachytherapy group. (orig.) [de

  15. A dose-response analysis for classical Kaposi's sarcoma management by radiotherapy

    International Nuclear Information System (INIS)

    Oysul, K.; Beyzadeoglu, M.; Surenkok, S.; Ozyigit, G.; Dirican, B.

    2008-01-01

    Objective was to evaluate the dose-response relationship in classical Kaposi's sarcoma CKS patients treated with external beam radiotherapy. Between 1993 and 2004, patients with CKS treated at the Department of Radiation Oncology, Gulhane Military Medical School, Ankara, Turkey were evaluated in this retrospective study. The median age at initial presentation was 60 years. First we analyzed the overall response rates for normalized total dose2Gy NTD2Gy of 20Gy. Secondly we searched for whether better response rates could be obtained with the NTD2Gy of >/=20Gy compared to the NTD2Gy of /20Gy and 64% and 24%for NDT2Gyof 20< Gy and these were statistically different p=0.001. Late side effects of radiation therapy were acceptable in all but 4 patients with fibrosis and edema. This retrospective analysis showed that radiotherapy schedules with an NDT2Gy of 20 Gy and above by using local irradiation fields are effective in terms of complete response rates in the management of CKS compared to NDT2Gy of < 20 Gy. (author)

  16. Configuration space analysis of common cost functions in radiotherapy beam-weight optimization algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Rowbottom, Carl Graham [Joint Department of Physics, Institute of Cancer Research and the Royal Marsden NHS Trust, Sutton, Surrey (United Kingdom); Webb, Steve [Joint Department of Physics, Institute of Cancer Research and the Royal Marsden NHS Trust, Sutton, Surrey (United Kingdom)

    2002-01-07

    The successful implementation of downhill search engines in radiotherapy optimization algorithms depends on the absence of local minima in the search space. Such techniques are much faster than stochastic optimization methods but may become trapped in local minima if they exist. A technique known as 'configuration space analysis' was applied to examine the search space of cost functions used in radiotherapy beam-weight optimization algorithms. A downhill-simplex beam-weight optimization algorithm was run repeatedly to produce a frequency distribution of final cost values. By plotting the frequency distribution as a function of final cost, the existence of local minima can be determined. Common cost functions such as the quadratic deviation of dose to the planning target volume (PTV), integral dose to organs-at-risk (OARs), dose-threshold and dose-volume constraints for OARs were studied. Combinations of the cost functions were also considered. The simple cost function terms such as the quadratic PTV dose and integral dose to OAR cost function terms are not susceptible to local minima. In contrast, dose-threshold and dose-volume OAR constraint cost function terms are able to produce local minima in the example case studied. (author)

  17. Postoperative complications following intraoperative radiotherapy in abdominopelvic malignancy: A single institution analysis of 113 consecutive patients.

    Science.gov (United States)

    Abdelfatah, Eihab; Page, Andrew; Sacks, Justin; Pierorazio, Phillip; Bivalacqua, Trinity; Efron, Jonathan; Terezakis, Stephanie; Gearhart, Susan; Fang, Sandy; Safar, Bashar; Pawlik, Timothy M; Armour, Elwood; Hacker-Prietz, Amy; Herman, Joseph; Ahuja, Nita

    2017-06-01

    Intraoperative radiotherapy (IORT) has advantages over external beam radiation therapy (EBRT). Few studies have described side effects associated with its addition. We evaluated our institution's experience with abdominopelvic IORT to assess safety by postoperative complication rates. Prospectively collected IRB-approved database of all patients receiving abdominopelvic IORT (via high dose rate brachytherapy) at Johns Hopkins Hospital between November 2006 and May 2014 was reviewed. Patients were discussed in multidisciplinary conferences. Those selected for IORT were patients for whom curative intent resection was planned for which IORT could improve margin-negative resection and optimize locoregional control. Perioperative complications were classified via Clavien-Dindo scale for postoperative surgical complications. A total of 113 patients were evaluated. Most common diagnosis was sarcoma (50/113, 44%) followed by colorectal cancer (45/113, 40%), most of which were recurrent (84%). There were no perioperative deaths. A total of 57% of patients experienced a complication Grade II or higher: 24% (27/113) Grade II; 27% (30/113) Grade III; 7% (8/113) Grade IV. Wound complications were most common (38%), then gastrointestinal (25%). No radiotherapy variables were significantly associated with complications on uni/multi-variate analysis. Our institution's experience with IORT demonstrated historically expected postoperative complication rates. IORT is safe, with acceptable perioperative morbidity. © 2017 Wiley Periodicals, Inc.

  18. Contribution to adaptive radiotherapy by systematic analysis of the entrance fluence and exit patient dose

    International Nuclear Information System (INIS)

    Celi, Sofia

    2016-01-01

    Modern radiation therapy combines complex techniques and personalized treatments, with the risk that certain evolutions and errors occurring during the course of the treatment might go unnoticed. These fluctuations may cause great damage to the health of the patient. In this perspective, we worked on the potential of a transit in vivo dosimetry system for continuous monitoring of the patient and, hereafter, adaptive radiotherapy. Our clinical experience and feasibility testing determined the main lines of work: automation and simplification of the results analysis method. The developments included the creation of a golden data library and a series of root cause analyzes, allowing us to strengthen the accuracy of the system, to enhance the automation of the setup and to identify tracks for an efficient analysis of the results and for the creation of additional analytical tools to facilitate the monitoring and adaptation of the treatments in clinical routine [fr

  19. Is IMRT Superior or Inferior to 3DCRT in Radiotherapy for NSCLC? A Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Xingsheng Hu

    Full Text Available There are no adequate data to determine whether intensity-modulated radiotherapy (IMRT is superior to three-dimensional conformal radiotherapy (3DCRT in the treatment of non-small cell lung cancer (NSCLC. This meta-analysis was conducted to compare the clinical outcomes of IMRT and 3DCRT in the treatment of NSCLC.No exclusions were made based on types of study design. We performed a literature search in PubMed, EMBASE and the Cochrane library databases from their inceptions to April 30, 2015. The overall survival (OS and relative risk (RR of radiation pneumonitis and radiation oesophagitis were evaluated. Two authors independently assessed the methodological quality and extracted data. Publication bias was evaluated by funnel plot using Egger's test results.From the literature search, 10 retrospective studies were collected, and of those, 5 (12,896 patients were selected for OS analysis, 4 (981 patients were selected for radiation pneumonitis analysis, and 4 (1339 patients were selected for radiation oesophagitis analysis. Cox multivariate proportional hazards models revealed that 3DCRT and IMRT had similar OS (HR = 0.96, P = 0.477 but that IMRT reduced the incidence of grade 2 radiation pneumonitis (RR = 0.74, P = 0.009 and increased the incidence of grade 3 radiation oesophagitis (RR = 2.47, P = 0.000.OS of IMRT for NSCLC is not inferior to that of 3DCRT, but IMRT significantly reduces the risk of radiation pneumonitis and increases the risk of radiation oesophagitis compared to 3DCRT.

  20. Comparison of different contouring definitions of the rectum as organ at risk (OAR) and dose-volume parameters predicting rectal inflammation in radiotherapy of prostate cancer: which definition to use?

    Science.gov (United States)

    Nitsche, Mirko; Brannath, Werner; Brückner, Matthias; Wagner, Dirk; Kaltenborn, Alexander; Temme, Nils; Hermann, Robert M

    2017-02-01

    The objective of this retrospective planning study was to find a contouring definition for the rectum as an organ at risk (OAR) in curative three-dimensional external beam radiotherapy (EBRT) for prostate cancer (PCa) with a predictive correlation between the dose-volume histogram (DVH) and rectal toxicity. In a pre-study, the planning CT scans of 23 patients with PCa receiving definitive EBRT were analyzed. The rectum was contoured according to 13 different definitions, and the dose distribution was correlated with the respective rectal volumes by generating DVH curves. Three definitions were identified to represent the most distinct differences in the shapes of the DVH curves: one anatomical definition recommended by the Radiation Therapy Oncology Group (RTOG) and two functional definitions based on the target volume. In the main study, the correlation between different relative DVH parameters derived from these three contouring definitions and the occurrence of rectal toxicity during and after EBRT was studied in two consecutive collectives. The first cohort consisted of 97 patients receiving primary curative EBRT and the second cohort consisted of 66 patients treated for biochemical recurrence after prostatectomy. Rectal toxicity was investigated by clinical investigation and scored according to the Common Terminology Criteria for Adverse Events. Candidate parameters were the volume of the rectum, mean dose, maximal dose, volume receiving at least 60 Gy (V 60 ), area under the DVH curve up to 25 Gy and area under the DVH curve up to 75 Gy in dependence of each chosen rectum definition. Multivariable logistic regression considered other clinical factors such as pelvine lymphatics vs local target volume, diabetes, prior rectal surgery, anticoagulation or haemorrhoids too. In Cohort 1 (primary EBRT), the mean rectal volumes for definitions "RTOG", planning target volume "(PTV)-based" and "PTV-linked" were 100 cm 3 [standard deviation (SD) 43 cm 3 ], 60

  1. Stereotactic radiosurgery versus whole-brain radiotherapy after intracranial metastasis resection : A systematic review and meta-analysis

    NARCIS (Netherlands)

    Lamba, Nayan; Muskens, Ivo S; DiRisio, Aislyn C; Meijer, Louise; Briceno, Vanessa; Edrees, Heba; Aslam, Bilal; Minhas, Sadia; Verhoeff, Joost J.C.; Kleynen, Catharina E.; Smith, Timothy R; Mekary, Rania A; Broekman, Marike L.

    2017-01-01

    Background: In patients with one to three brain metastases who undergo resection, options for post-operative treatments include whole-brain radiotherapy (WBRT) or stereotactic radiosurgery (SRS) of the resection cavity. In this meta-analysis, we sought to compare the efficacy of each post-operative

  2. Analysis of the efficacy and safety of conventional radiotherapy of chest wall and clavicular field and three-dimensional conformal radiotherapy in patients after modified radical mastectomy

    Directory of Open Access Journals (Sweden)

    Song-Lin Wang

    2017-04-01

    Full Text Available Objective: To explore the efficacy and safety of conventional radiotherapy of chest wall and clavicular field and three-dimensional conformal radiotherapy in patients after modified radical mastectomy. Methods: A total of 84 patients who were admitted in our hospital after modified radical mastectomy were included in the study and divided into the conventional radiotherapy group (n=42 and the three-dimensional conformal radiotherapy group (n=42 according to different radiotherapy methods. The patients in the conventional radiotherapy group were given conventional radiotherapy of chest wall and clavicular field, while the patients in the three-dimensional conformal radiotherapy group were given three-dimensional conformal radiotherapy. The serum tumor markers and peripheral blood T lymphocyte subsets 6-8 weeks after treatment in the two groups were detected. The clinical efficacy, and toxic and side effects in the two groups were evaluated. Results: The serum CA15-3, CA125, CEA, and CK19 levels after treatment in the two groups were significantly reduced when compared with before treatment, CD3 +,CD4 +, and CD4 +/CD8 + were significantly elevated, while CD8 + was significantly reduced when compared with before treatment, but the comparison of the above indicators between the two groups was not statistically significant. The occurrence rate of radioactive skin damage and pneumonia after treatment in the conventional radiotherapy group was significantly higher than that in the three-dimensional conformal radiotherapy group. Conclusions: The two kinds of radiotherapy schemes have an equal efficacy, but the toxic and side effects of three-dimensional conformal radiotherapy are significantly lower than those by the conventional radiotherapy, with a certain advantage.

  3. An analysis of two separate quality audits in UK radiotherapy centres

    International Nuclear Information System (INIS)

    Aird, E G A

    1995-01-01

    The CHART quality assurance programme has been used to audit 2 groups of radiotherapy centres for the delivery of radiotherapy: 1. those involved in the CHART Clinical Trial (1991-1995) 2. all London radiotherapy centres (1994-1996) Machinery Tests This paper will seek to illustrate improvements in meeting the criteria set by the QA programme as older linear accelerators are replaced. Phantom Tests The residual errors between measured and calculated doses in anatomical phantoms will be analysed to demonstrate where there are still weaknesses in treatment planning and delivery of radiotherapy

  4. Present-day radiotherapy: analysis of the sate of the art and outlook in the future

    International Nuclear Information System (INIS)

    Dar'yalova, S.P.; Bojko, A.V.; Chernichenko, A.V.; Kiceleva, E.S.; Kvasov, V.A.

    1995-01-01

    Analyzes the development of radiotherapy as exemplified by experience gained by P.A.Herzen Oncological Research Dulines the priority of radiotherapy for the nearest future. It is, firet and foremost, chemoradiotherapy making use of both, intravenous polychemotherapy and intra-and paratumoral injection of drugs: intraoperative exposure to electron beam of different energies using gaseous hypoxia; laser exposure together with combined radiotherapy for the treatment of tracheobronchial, esofophageal, rectal, and genital cancers. Validates and presents the results of nontraditional protocols of downs fractionation and radiomodifier use. Formulates the ideology of present-day radiotherapy. 21 refs., 3 figs., 6 tabs

  5. Diode In-vivo Dosimetry for External Beam Radiotherapy: Patient Data Analysis

    International Nuclear Information System (INIS)

    Mrcela, I.; Bokulic, T.; Budanec, M; Froebe, A.; Soldic, Z.; Kusic, Z.

    2008-01-01

    In-vivo dosimetry is known as simple and reliable method for checking the final accuracy of the dose delivered in external radiotherapy making a supplement to the regular quality control. Entrance dose measurements in the beginning of the treatment assure detection of major errors that can affect the therapy outcome. Silicon diodes are often the detectors of choice for their ability of real time dose measurements and the simplicity of use. There are many publications describing the procedures for the implementation of in-vivo dosimetry. Routine in-vivo dosimetry has been introduced in our department after initial procedures including physical characterization, calibration and determination of correction factors for the detectors in use. This work presents patient data analysis with more than 700 field measurements taken in last 2 years period

  6. Analysis of complications of cervix carcinoma treated by radiotherapy using the Franco-Italian glossary

    International Nuclear Information System (INIS)

    Sinistrero, G.; Sismondi, P.; Rumore, A.; Zola, P.

    1993-01-01

    We analysed the complications of 215 patients with uterine cervix cancer, treated by radiotherapy (RT) alone. It was done according to the rules of the Franco-Italian glossary, presented at the 7th ESTRO meeting, held in The Hague on September 1988. They were ranked by organ sites and by degrees of gravity. The analysis was done on the total number of complications and they were scored at the highest reached grade of gravity. Seventy one complications were found in 55 patients; they were studied by patient, degree of severity, time of onset, organ system and grade, time of onset and grade, time of onset and organ sites, stage and RT doses and brachytherapy volumes. The importance of the study of complications is stressed, particularly when treatment combines external RT and brachytherapy; some guidelines are given to avoid severe complications. (author) tabs. figs

  7. Analysis of complications of cervix carcinoma treated by radiotherapy using the Franco-Italian glossary.

    Science.gov (United States)

    Sinistrero, G; Sismondi, P; Rumore, A; Zola, P

    1993-03-01

    We analysed the complications of 215 patients with uterine cervix cancer, treated by radiotherapy (RT) alone. It was done according to the rules of the Franco-Italian glossary, presented at the 7th ESTRO meeting, held in The Hague on September 1988. They were ranked by organ sites and by degrees of gravity. The analysis was done on the total number of complications and they were scored at the highest reached grade of gravity. Seventy one complications were found in 55 patients; they were studied by patient, degree of severity, time of onset, organ system and grade, time of onset and grade, time of onset and organ sites, stage and RT doses and brachytherapy volumes. The importance of the study of complications is stressed, particularly when treatment combines external RT and brachytherapy; some guidelines are given to avoid severe complications.

  8. ROC analysis of benefit and limitation in radiotherapy for cancer of the oral cavity

    International Nuclear Information System (INIS)

    Maciejewski, B.; Zajusz, A.

    1993-01-01

    The ROC (receiver operating characteristic) analysis of optimization of radiation treatment of cancer of oral cavity was carried out. Material of 210 patients with squamous cell carcinoma of the oral cavity was included into the study. Based on dose-response curves for tumor and late mucosal reactions, iso-utility curves and optimal k values were estimated. Optimal k values decreased from 0.792 to 0.584 with extension of overall treatment time from 35 to 49 days. This may suggest that the planning of additional dose to compensate tumor clonogens repopulation during prolonged treatment does not improve the therapeutic gain in radiotherapy for cancer of the oral cavity. The ROC is a useful model to estimate the optimal radiation treatment for a given tumor because it is independent of any arbitrary consensus or theoretical assumption. (author) 1 tab., 3 figs., 5 refs

  9. Bibliometrics of intraoperative radiotherapy. Analysis of technology, practice and publication tendencies

    International Nuclear Information System (INIS)

    Sole, Claudio V.; Calvo, Felipe A.; Ferrer, Carlos; Pascau, Javier; Marsiglia, Hugo

    2014-01-01

    To analyze the performance and quality of intraoperative radiation therapy (IORT) publications identified in medical databases during a recent period in terms of bibliographic metrics. A bibliometric search was conducted for IORT papers published in the PubMed database between 1997 and 2013. Publication rate was used as a quantity indicator; the 2012 Science Citation Index Impact Factor as a quality indicator. Furthermore, the publications were stratified in terms of study type, scientific topic reported, year of publication, tumor type and journal specialty. We performed a one-way analysis of variance (ANOVA) to determine differences between the means of the analyzed groups. Among the total of 207 journals, articles were reported significantly more frequently in surgery (n = 399, 41 %) and radiotherapy journals (n = 273, 28 %; p [de

  10. Preoperative radiotherapy in esophageal carcinoma: a meta-analysis using individual patient data (oesophageal cancer collaborative group)

    International Nuclear Information System (INIS)

    Arnott, Sydney J.; Duncan, William; Gignoux, Marc; Girling, David J.; Hansen, Hanne S.; Launois, B.; Nygaard, Knut; Parmar, Mahesh K.B.; Roussel, Alain; Spiliopoulos, G.; Stewart, Lesley A.; Tierney, Jayne F.; Wang Mei; Zhang Rugang

    1998-01-01

    Purpose: The existing randomized evidence has failed to conclusively demonstrate the benefit or otherwise of preoperative radiotherapy in treating patients with potentially resectable esophageal carcinoma. This meta-analysis aimed to assess whether there is benefit from adding radiotherapy prior to surgery. Methods and Materials: This quantitative meta-analysis included updated individual patient data from all properly randomized trials (published or unpublished) comprising 1147 patients (971 deaths) from five randomized trials. Results: With a median follow-up of 9 years, the hazard ratio (HR) of 0.89 (95% CI 0.78-1.01) suggests an overall reduction in the risk of death of 11% and an absolute survival benefit of 3% at 2 years and 4% at 5 years. This result is not conventionally statistically significant (p 0.062). No clear differences in the size of the effect by sex, age, or tumor location were apparent. Conclusion: Based on existing trials, there was no clear evidence that preoperative radiotherapy improves the survival of patients with potentially resectable esophageal cancer. These results indicate that if such preoperative radiotherapy regimens do improve survival, then the effect is likely to be modest with an absolute improvement in survival of around 3 to 4%. Trials or a meta-analysis of around 2000 patients would be needed to reliably detect such an improvement (15→20%)

  11. Intensity-modulated radiotherapy -the State of the Art

    International Nuclear Information System (INIS)

    Ling, C.

    2002-01-01

    Full text: In the last two decades of the last century, the development of three-dimensional conformal radiotherapy (3D-CRT) has substantially reduces the volume of critical organs irradiated to high doses, and has permitted the increase of tumor dose without concomitant increase in normal tissue complication. At Memorial Sloan Kettering Cancer Center, a clinical trial in cancer of the prostate has accrued >1600 patient and the prescription dose has been escalated to 81 Gy with 3D-CRT, and to 86.4 Gy using intensity modulated radiotherapy (IMRT), with promising results. 3D-CRT and IMRT involves the delineation of target and non-target structures from patient-specific 3D image data-sets (primarily CT, sometimes supplemented with MRI, PET etc.), the calculation and display of 3D dose distributions, the analysis and evaluation of structure-specific dose-volume data (DVH-dose volume histogram), radiation delivery with computer-controlled multileaf collimators (MLC), and treatment verification with electronic portal images. However, the dose distribution conformality achieved with 3D-CRT can be further improved by the use of computer-optimized IMRT. In addition, the treatment design phase of 3D-CRT involves several iterative steps and can be time-consuming, particularly when the anatomical geometry is complex. Thus, IMRT is an incremental advance from 3D-CRT with two key enhancements: 1) computerized iterative treatment plan optimization, and 2) the use of intensity-modulated radiation beams. To deliver the IM beams, one efficacious approach is to use MLC in the dynamic mode, using the so-called sliding-window technique, i.e. the leaves of the MLC are in motion while the radiation is being delivered. Since 1995, we have treated over 1500 patients with IMRT. This discussion shall describe the physical aspects of IMRT, emphasizing those features and benefits unique to this approach. Pertinent clinical results will also be briefly presented

  12. Stability analysis of a deterministic dose calculation for MRI-guided radiotherapy

    Science.gov (United States)

    Zelyak, O.; Fallone, B. G.; St-Aubin, J.

    2018-01-01

    Modern effort in radiotherapy to address the challenges of tumor localization and motion has led to the development of MRI guided radiotherapy technologies. Accurate dose calculations must properly account for the effects of the MRI magnetic fields. Previous work has investigated the accuracy of a deterministic linear Boltzmann transport equation (LBTE) solver that includes magnetic field, but not the stability of the iterative solution method. In this work, we perform a stability analysis of this deterministic algorithm including an investigation of the convergence rate dependencies on the magnetic field, material density, energy, and anisotropy expansion. The iterative convergence rate of the continuous and discretized LBTE including magnetic fields is determined by analyzing the spectral radius using Fourier analysis for the stationary source iteration (SI) scheme. The spectral radius is calculated when the magnetic field is included (1) as a part of the iteration source, and (2) inside the streaming-collision operator. The non-stationary Krylov subspace solver GMRES is also investigated as a potential method to accelerate the iterative convergence, and an angular parallel computing methodology is investigated as a method to enhance the efficiency of the calculation. SI is found to be unstable when the magnetic field is part of the iteration source, but unconditionally stable when the magnetic field is included in the streaming-collision operator. The discretized LBTE with magnetic fields using a space-angle upwind stabilized discontinuous finite element method (DFEM) was also found to be unconditionally stable, but the spectral radius rapidly reaches unity for very low-density media and increasing magnetic field strengths indicating arbitrarily slow convergence rates. However, GMRES is shown to significantly accelerate the DFEM convergence rate showing only a weak dependence on the magnetic field. In addition, the use of an angular parallel computing strategy

  13. Corrigendum to "Stability analysis of a deterministic dose calculation for MRI-guided radiotherapy".

    Science.gov (United States)

    Zelyak, Oleksandr; Fallone, B Gino; St-Aubin, Joel

    2018-03-12

    Modern effort in radiotherapy to address the challenges of tumor localization and motion has led to the development of MRI guided radiotherapy technologies. Accurate dose calculations must properly account for the effects of the MRI magnetic fields. Previous work has investigated the accuracy of a deterministic linear Boltzmann transport equation (LBTE) solver that includes magnetic field, but not the stability of the iterative solution method. In this work, we perform a stability analysis of this deterministic algorithm including an investigation of the convergence rate dependencies on the magnetic field, material density, energy, and anisotropy expansion. The iterative convergence rate of the continuous and discretized LBTE including magnetic fields is determined by analyzing the spectral radius using Fourier analysis for the stationary source iteration (SI) scheme. The spectral radius is calculated when the magnetic field is included (1) as a part of the iteration source, and (2) inside the streaming-collision operator. The non-stationary Krylov subspace solver GMRES is also investigated as a potential method to accelerate the iterative convergence, and an angular parallel computing methodology is investigated as a method to enhance the efficiency of the calculation. SI is found to be unstable when the magnetic field is part of the iteration source, but unconditionally stable when the magnetic field is included in the streaming-collision operator. The discretized LBTE with magnetic fields using a space-angle upwind stabilized discontinuous finite element method (DFEM) was also found to be unconditionally stable, but the spectral radius rapidly reaches unity for very low density media and increasing magnetic field strengths indicating arbitrarily slow convergence rates. However, GMRES is shown to significantly accelerate the DFEM convergence rate showing only a weak dependence on the magnetic field. In addition, the use of an angular parallel computing strategy

  14. Stability analysis of a deterministic dose calculation for MRI-guided radiotherapy.

    Science.gov (United States)

    Zelyak, O; Fallone, B G; St-Aubin, J

    2017-12-14

    Modern effort in radiotherapy to address the challenges of tumor localization and motion has led to the development of MRI guided radiotherapy technologies. Accurate dose calculations must properly account for the effects of the MRI magnetic fields. Previous work has investigated the accuracy of a deterministic linear Boltzmann transport equation (LBTE) solver that includes magnetic field, but not the stability of the iterative solution method. In this work, we perform a stability analysis of this deterministic algorithm including an investigation of the convergence rate dependencies on the magnetic field, material density, energy, and anisotropy expansion. The iterative convergence rate of the continuous and discretized LBTE including magnetic fields is determined by analyzing the spectral radius using Fourier analysis for the stationary source iteration (SI) scheme. The spectral radius is calculated when the magnetic field is included (1) as a part of the iteration source, and (2) inside the streaming-collision operator. The non-stationary Krylov subspace solver GMRES is also investigated as a potential method to accelerate the iterative convergence, and an angular parallel computing methodology is investigated as a method to enhance the efficiency of the calculation. SI is found to be unstable when the magnetic field is part of the iteration source, but unconditionally stable when the magnetic field is included in the streaming-collision operator. The discretized LBTE with magnetic fields using a space-angle upwind stabilized discontinuous finite element method (DFEM) was also found to be unconditionally stable, but the spectral radius rapidly reaches unity for very low-density media and increasing magnetic field strengths indicating arbitrarily slow convergence rates. However, GMRES is shown to significantly accelerate the DFEM convergence rate showing only a weak dependence on the magnetic field. In addition, the use of an angular parallel computing strategy

  15. Considerations for using data envelopment analysis for the assessment of radiotherapy treatment plan quality.

    Science.gov (United States)

    Simpson, John; Raith, Andrea; Rouse, Paul; Ehrgott, Matthias

    2017-10-09

    Purpose The operations research method of data envelopment analysis (DEA) shows promise for assessing radiotherapy treatment plan quality. The purpose of this paper is to consider the technical requirements for using DEA for plan assessment. Design/methodology/approach In total, 41 prostate treatment plans were retrospectively analysed using the DEA method. The authors investigate the impact of DEA weight restrictions with reference to the ability to differentiate plan performance at a level of clinical significance. Patient geometry influences plan quality and the authors compare differing approaches for managing patient geometry within the DEA method. Findings The input-oriented DEA method is the method of choice when performing plan analysis using the key undesirable plan metrics as the DEA inputs. When considering multiple inputs, it is necessary to constrain the DEA input weights in order to identify potential plan improvements at a level of clinical significance. All tested approaches for the consideration of patient geometry yielded consistent results. Research limitations/implications This work is based on prostate plans and individual recommendations would therefore need to be validated for other treatment sites. Notwithstanding, the method that requires both optimised DEA weights according to clinical significance and appropriate accounting for patient geometric factors is universally applicable. Practical implications DEA can potentially be used during treatment plan development to guide the planning process or alternatively used retrospectively for treatment plan quality audit. Social implications DEA is independent of the planning system platform and therefore has the potential to be used for multi-institutional quality audit. Originality/value To the authors' knowledge, this is the first published examination of the optimal approach in the use of DEA for radiotherapy treatment plan assessment.

  16. Analysis of the perception of risk of radiotherapy services in the metropolitan region of Rio de Janeiro using the risk evaluation system in radiotherapy (SEVRRA / FORUM)

    International Nuclear Information System (INIS)

    Burgos, Adam de Freitas

    2015-01-01

    In this work it was possible to analyze the perception of risks associated with existing processes in the high-dose rate brachytherapy and teletherapy using linear accelerators of radiotherapy services in the metropolitan area of Rio de Janeiro, through the combined use of two proposed methods: FMECA and risk matrix, using a general analysis and other more specific ones. The database software (SEVRRA) was used to identify possible existing processes in radiotherapy services (brachytherapy and teletherapy) and to classify the sequence of events in risk levels. The risk levels were analyzed at each stage and sub-stage, present in the treatment of patients undergoing high dose rate gynecological intracavitary brachytherapy and teletherapy treatments with the use of linear accelerators applying electron or photon beams in order to establish recommendations to the risks of highest priority for each case. The results show that although the procedure of high dose rate brachytherapy be automated and less susceptible to errors or failures, daily, one can still find considerable amounts of processes with worrying levels of risk perception. The processes that are more subject to radiological accident risks was associated with procedures, for of which the majority of the failures record and planning step of the treatment. The controls analyzed showed low efficiency, warning of the need to seek and implement new more efficient controls in routine brachytherapy for each participant service. About teletherapy procedure it was found that most of the failures were related to the registration and planning of treatment and equipment stages. The controls analyzed to teletherapy showed a poor result with a first type of analysis performed by suggesting a new type of more appropriate analysis. With a second type of analysis, these controls could be better analyzed and showed an order of importance according to a percentage of efficiency. Controls such as 'Double-check', &apos

  17. Meta-analysis of Genome Wide Association Studies Identifies Genetic Markers of Late Toxicity Following Radiotherapy for Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Sarah L. Kerns

    2016-08-01

    Full Text Available Nearly 50% of cancer patients undergo radiotherapy. Late radiotherapy toxicity affects quality-of-life in long-term cancer survivors and risk of side-effects in a minority limits doses prescribed to the majority of patients. Development of a test predicting risk of toxicity could benefit many cancer patients. We aimed to meta-analyze individual level data from four genome-wide association studies from prostate cancer radiotherapy cohorts including 1564 men to identify genetic markers of toxicity. Prospectively assessed two-year toxicity endpoints (urinary frequency, decreased urine stream, rectal bleeding, overall toxicity and single nucleotide polymorphism (SNP associations were tested using multivariable regression, adjusting for clinical and patient-related risk factors. A fixed-effects meta-analysis identified two SNPs: rs17599026 on 5q31.2 with urinary frequency (odds ratio [OR] 3.12, 95% confidence interval [CI] 2.08–4.69, p-value 4.16 × 10−8 and rs7720298 on 5p15.2 with decreased urine stream (OR 2.71, 95% CI 1.90–3.86, p-value = 3.21 × 10−8. These SNPs lie within genes that are expressed in tissues adversely affected by pelvic radiotherapy including bladder, kidney, rectum and small intestine. The results show that heterogeneous radiotherapy cohorts can be combined to identify new moderate-penetrance genetic variants associated with radiotherapy toxicity. The work provides a basis for larger collaborative efforts to identify enough variants for a future test involving polygenic risk profiling.

  18. [Cost analysis of radiotherapy provided in inpatient setting -  testing potential predictors for a new prospective payment system].

    Science.gov (United States)

    Sedo, J; Bláha, M; Pavlík, T; Klika, P; Dušek, L; Büchler, T; Abrahámová, J; Srámek, V; Slampa, P; Komínek, L; Pospíšil, P; Sláma, O; Vyzula, R

    2014-01-01

    As a part of the development of a new prospective payment model for radiotherapy we analyzed data on costs of care provided by three comprehensive cancer centers in the Czech Republic. Our aim was to find a combination of variables (predictors) which could be used to sort hospitalization cases into groups according to their costs, with each group having the same reimbursement rate. We tested four variables as possible predictors -  number of fractions, stage of disease, radiotherapy technique and diagnostic group. We analyzed 7,440 hospitalization cases treated in three comprehensive cancer centers from 2007 to 2011. We acquired data from the I COP database developed by Institute of Biostatistics and Analyses of Masaryk University in cooperation with oncology centers that contains records from the National Oncological Registry along with data supplied by healthcare providers to insurance companies for the purpose of retrospective reimbursement. When comparing the four variables mentioned above we found that number of fractions and radiotherapy technique were much stronger predictors than the other two variables. Stage of disease did not prove to be a relevant indicator of cost distinction. There were significant differences in costs among diagnostic groups but these were mostly driven by the technique of radiotherapy and the number of fractions. Within the diagnostic groups, the distribution of costs was too heterogeneous for the purpose of the new payment model. The combination of number of fractions and radiotherapy technique appears to be the most appropriate cost predictors to be involved in the prospective payment model proposal. Further analysis is planned to test the predictive value of intention of radiotherapy in order to determine differences in costs between palliative and curative treatment.

  19. Outcome analysis of salvage radiotherapy for occult cervical cancer found after simple hysterectomy

    International Nuclear Information System (INIS)

    Koh, Hyeon-Kang; Jeon, Wan; Kim, Hak-Jae; Wu, Hong-Gyun; Kim, Kyubo; Chie, Eui-Kyu; Ha, Sung-W.

    2013-01-01

    The objective was to analyze the outcomes of the patients, who received salvage radiotherapy for incidentally discovered cervical cancer following simple hysterectomy, and to identify the influence of intracavitary radiotherapy on treatment outcomes. Data from 117 patients with occult cervical cancer who underwent simple hysterectomy followed by salvage radiotherapy from September 1979 to November 2010 were collected. All the patients received external beam radiotherapy with (n=45) or without (n=72) intracavitary radiotherapy. Local control, disease-free survival, overall survival and treatment-related toxicity were investigated. The median follow-up time was 75 months. The 5- and 10-year local control/disease-free survival/overall survival rates were 93/87/87% and 90/84/83%, respectively. Among 98 patients who had no residual disease and negative resection margin on surgical specimens, 32 (33%) received intracavitary radiotherapy and 66 (67%) did not. There were no differences in patient and tumor characteristics between patients treated with and without intracavitary radiotherapy. The 5-year local control rate for the non-intracavitary radiotherapy group was 93 versus 94% for the intracavitary radiotherapy group (P=0.564); the disease-free survival rate was 88 versus 94% (P=0.894); the overall survival rate was 95 versus 85% (P=0.106), respectively. Among all patients, there were 5% of Grade 3 or higher late toxicities. Patients with occult invasive cervical cancer discovered following simple hysterectomy could be treated safely and effectively with salvage radiotherapy. For patients with no residual disease and negative resection margin, intracavitary radiotherapy could be omitted. (author)

  20. Analysis of patterns of palliative radiotherapy in north west India: A regional cancer center experience

    Directory of Open Access Journals (Sweden)

    Akhil Kapoor

    2015-01-01

    Full Text Available Background: Palliative radiotherapy (PRT is the eventual requirement in 30-50% of all cancer patients. PRT is primarily aimed to relieve pain and prevent/treat collapse or fracture in case of bone metastasis, to reduce edema in patients with cranial metastasis, and to control distressing symptoms of rapid primary growth. An audit of PRT planned in a busy cancer center can help in the characterization of the requirements of the patients and the formulation of institutional policies. Materials and Methods: In total, 516 patients who received PRT in our regional cancer center from January 2012 to December 2012 and whose complete records were available for analysis were selected for this retrospective study. Medical records and radiotherapy files were analyzed to obtain data such as sociodemographic parameters, prescription of PRT, and follow up. Descriptive statistics were evaluated in terms of frequencies and percentages to allow comparisons. Results: Of the 516 patients, 73% patients were male; the median age of the patients receiving PRT was 62 years (range 13-83 years. About 48% ( n = 248 patients received PRT at the primary site while rest (52% were given PRT at the metastatic site. The most common indication of PRT was pain (56.8% cases, followed by cytostatic PRT (19.8% and raised ICT (12.4%. The median dose prescribed was 30 Gy (range 8-36 Gy delivered in 1-12 fractions over the duration of 1-18 days. The overall response rate was about 43% at 2 weeks of completion of PRT; the median follow-up of the patients was 154 days (range 9-256 days. The long-term symptom relief at median follow up was 8%. Conclusions: Good clinical judgment and expertise is required in prescribing correct fractionation schedule to achieve effective symptom palliation with lowest possible cost and inconvenience to the patients and relatives. Hypofractionated radiotherapy is a feasible treatment option in patients with advanced incurable disease to achieve effective

  1. Role of postoperative radiotherapy for celiac lymph node metastasis from gastric cancer: analysis on 63 patients

    International Nuclear Information System (INIS)

    Sun Jing; Sun Yihong; Qin Xinyu; Zeng Mengsu; Wang Minhua; Zeng Zhaochong

    2007-01-01

    Objective: To evaluate the role of postoperative radiotherapy for celiac lymph node (LN) metastasis from gastric cancer in the past 6 years. Methods: Sixty-three patients with abdominal LN metastasis after curative resection for gastric cancer were retrospectively analyzed. Clinical characteristics was colleeted including age, gender, status of primary tumor of stomach (size, location and grade), and the number of LN dissected and involved. Of the 63 patients, 36 received local external beam radiotherapy (EBRT) as salvage therapy and were classified as the EBRT group. The irradiation target was local-regional LN. The radiation dose ranged from 40 to 60 Gy in daily 1.8-2.0 Gy fractions, 5 times weekly. The other 27 patients who received chemotherapy were classified as the non-EBRT group. The Kaplan-Meier method was used to evaluate the survival rates, and the Cox regression model was used to identify the predictors of prognosis. Results: After EBRT, complete response and partial response were observed in 31% and 58% of patients, respectively. The clinical obstruction symptoms induced by LN pressure in 18 patients were completely relieved after EBRT. The median survival was 339 clays for the EBRT group and 136 days for the non- EBRT group, the survival rate at 1 and 2 years for patients treated with EBRT vs. without EBRT was 40% vs. 17% and 20% vs. 6%, respectively (P=0.004). Multivariate analysis showed that the level of relative risk (RR) in the EBRT group was reduced to 0.299 (P=0.002). The incidence of death resulting from LN-related complications was lower in the EBRT group. The main cause of death in both groups was distant metastasis. The gastro-intestinal toxicities were the most common side effects during and after EBRT. The RTOG grade 0,1,2 and 3 toxicities were found in 7,17,11 and 1 patients, respectively. No hematologic and hepatic toxicities were observed. Conclusions: Postoperative lymph node metastasis from gastric cancer is sensitive to external beam

  2. Analysis of whole Breast Radiotherapy Methods for Treatment of Early Stage Breast Cancer after Conserving Surgery

    International Nuclear Information System (INIS)

    Utehina, O.; Popovs, S.; Berzins, J.

    2007-01-01

    Introduction. At present moment breast cancer in Latvia is at second place for whole population and at first place among women. In year 2004 there were 1012 new breast cancer cases discovered. There was growth in number of breast cancer patients from 58.6 per 100 000 inhabitants in 1995 to 80.4 per 100 000 inhabitants in 2004. This growth is primarily attributed to breast cancer screening program which is nowadays active in Latvia. Breast cancer is third death cause among cancers in Latvia, - in 1995 there where 27.4 deaths per 100 000 inhabitants and in 2004 - 36.2 deaths per 100 000 inhabitants. Due to screening program there is increasing number of patients with stage I and II breast cancer. In 2004 toe where 9884 women with breast cancer registered in Latvian Cancer Registry and among them 79 percent were presented as stage I or II. Breast conservative surgery with adjuvant radiotherapy as standard part of it plays great role in breast cancer treatment in our Center. In year 2004 there were 103 breast conservative surgeries performed in our Center. Radiotherapy is a standard part of treatment in modem breast saving operations for early stage breast cancer, At present, only whole breast postoperative irradiation is performed in Latvia. For selected group of patients this treatment can be substituted with other radiotherapy methods in order to reduce acute reactions and/or late toxicity, maintaining the same tumor control. Aim of this work is to show that during whole breast irradiation dose maximum and tissue volume which receives doses more than 105% from prescribed dose, is linked with size of treated volume (treated volume - tissue volume receiving > 95% from prescribed dose), which is strictly linked with breast volume. Because of this for large breast volumes there is higher complication probability performing whole breast irradiation, and it seems to be meaningful to use Intensity Modulated Radiotherapy or Accelerated Partial Breast Irradiation for

  3. SU-F-T-419: Evaluation of PlanIQ Feasibility DVH as Planning Objectives for Skull Base SBRT Patients

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, W [School of Medicine, Qingdao University, Yantai, Shandong (China); Wang, H; Chi, P [University of Texas, M.D. Anderson Cancer Center, Houston, TX (United States)

    2016-06-15

    Purpose: PlanIQ(Sun Nuclear Corporation) can provide feasibility measures on organs-at-risk(OARs) around the target based on depth, local anatomy density and energy of radiation beam used. This study is to test and evaluate PlanIQ feasibility DVHs as optimization objectives in the treatment planning process, and to investigate the potential to use them in routine clinical cases to improve planning efficiency. Methods: Two to three arcs VMAT Treatment plans were generated in Pinnacle based on PlanIQ feasibility DVH for six skull base patients who previously treated with SBRT. The PlanIQ feasibility DVH for each OAR consists of four zones – impossible (at 100% target coverage), difficult, challenging and probable. Constrains to achieve DVH in difficult zone were used to start plan optimization. Further adjustment was made to improve coverage. The plan DVHs were compared to PlanIQ feasibility DVH to assess the dose received by 0%(D0), 5%(D5), 10%(D10) and 50%(D50) of the OAR volumes. Results: A total of 90 OARs were evaluated for 6 patients (mean 15 OARs, range 11–18 OARs). We used >98% PTV coverage as planning goal since it’s difficult to achieve 100% target coverage. For the generated plans, 96.7% of the OARs achieved D0 or D5 within difficult zone or impossible zone (ipsilateral OARs 93.5%, contralateral OARs 100%), while 90% and 65.6% of the OARs achieved D10 and D50 within difficult zone, respectively. Seventeen of the contralateral and out of field OARs achieved DVHs in impossible zone. For OARs adjacent or overlapped with target volume, the D0 and D5 are challenging to be optimized into difficult zone. All plans were completed within 2–4 adjustments to improve target coverage and uniformity. Conclusion: PlanIQ feasibility tool has the potential to provide difficult but achievable initial optimization objectives and therefore reduce the planning time to obtain a well optimized plan.

  4. SU-E-T-596: P3DVHStats - a Novel, Automatic, Institution Customizable Program to Compute and Report DVH Quantities On Philips Pinnacle TPS

    International Nuclear Information System (INIS)

    Wu, C

    2015-01-01

    Purpose: To implement a novel, automatic, institutional customizable DVH quantities evaluation and PDF report tool on Philips Pinnacle treatment planning system (TPS) Methods: An add-on program (P3DVHStats) is developed by us to enable automatic DVH quantities evaluation (including both volume and dose based quantities, such as V98, V100, D2), and automatic PDF format report generation, for EMR convenience. The implementation is based on a combination of Philips Pinnacle scripting tool and Java language pre-installed on each Pinnacle Sun Solaris workstation. A single Pinnacle script provide user a convenient access to the program when needed. The activated script will first export DVH data for user selected ROIs from current Pinnacle plan trial; a Java program then provides a simple GUI interface, utilizes the data to compute any user requested DVH quantities, compare with preset institutional DVH planning goals; if accepted by users, the program will also generate a PDF report of the results and export it from Pinnacle to EMR import folder via FTP. Results: The program was tested thoroughly and has been released for clinical use at our institution (Pinnacle Enterprise server with both thin clients and P3PC access), for all dosimetry and physics staff, with excellent feedback. It used to take a few minutes to use MS-Excel worksheet to calculate these DVH quantities for IMRT/VMAT plans, and manually save them as PDF report; with the new program, it literally takes a few mouse clicks in less than 30 seconds to complete the same tasks. Conclusion: A Pinnacle scripting and Java language based program is successfully implemented, customized to our institutional needs. It is shown to dramatically reduce time and effort needed for DVH quantities computing and EMR reporting

  5. SU-E-T-596: P3DVHStats - a Novel, Automatic, Institution Customizable Program to Compute and Report DVH Quantities On Philips Pinnacle TPS

    Energy Technology Data Exchange (ETDEWEB)

    Wu, C [Sutter Medical Foundation, Roseville, CA (United States)

    2015-06-15

    Purpose: To implement a novel, automatic, institutional customizable DVH quantities evaluation and PDF report tool on Philips Pinnacle treatment planning system (TPS) Methods: An add-on program (P3DVHStats) is developed by us to enable automatic DVH quantities evaluation (including both volume and dose based quantities, such as V98, V100, D2), and automatic PDF format report generation, for EMR convenience. The implementation is based on a combination of Philips Pinnacle scripting tool and Java language pre-installed on each Pinnacle Sun Solaris workstation. A single Pinnacle script provide user a convenient access to the program when needed. The activated script will first export DVH data for user selected ROIs from current Pinnacle plan trial; a Java program then provides a simple GUI interface, utilizes the data to compute any user requested DVH quantities, compare with preset institutional DVH planning goals; if accepted by users, the program will also generate a PDF report of the results and export it from Pinnacle to EMR import folder via FTP. Results: The program was tested thoroughly and has been released for clinical use at our institution (Pinnacle Enterprise server with both thin clients and P3PC access), for all dosimetry and physics staff, with excellent feedback. It used to take a few minutes to use MS-Excel worksheet to calculate these DVH quantities for IMRT/VMAT plans, and manually save them as PDF report; with the new program, it literally takes a few mouse clicks in less than 30 seconds to complete the same tasks. Conclusion: A Pinnacle scripting and Java language based program is successfully implemented, customized to our institutional needs. It is shown to dramatically reduce time and effort needed for DVH quantities computing and EMR reporting.

  6. Quality assessment for VMAT prostate radiotherapy planning based on data envelopment analysis

    International Nuclear Information System (INIS)

    Lin, Kuan-Min; Simpson, John; Raith, Andrea; Ehrgott, Matthias; Sasso, Giuseppe

    2013-01-01

    The majority of commercial radiotherapy treatment planning systems requires planners to iteratively adjust the plan parameters in order to find a satisfactory plan. This iterative trial-and-error nature of radiotherapy treatment planning results in an inefficient planning process and in order to reduce such inefficiency, plans can be accepted without achieving the best attainable quality. We propose a quality assessment method based on data envelopment analysis (DEA) to address this inefficiency. This method compares a plan of interest to a set of past delivered plans and searches for evidence of potential further improvement. With the assistance of DEA, planners will be able to make informed decisions on whether further planning is required and ensure that a plan is only accepted when the plan quality is close to the best attainable one. We apply the DEA method to 37 prostate plans using two assessment parameters: rectal generalized equivalent uniform dose (gEUD) as the input and D95 (the minimum dose that is received by 95% volume of a structure) of the planning target volume (PTV) as the output. The percentage volume of rectum overlapping PTV is used to account for anatomical variations between patients and is included in the model as a non-discretionary output variable. Five plans that are considered of lesser quality by DEA are re-optimized with the goal to further improve rectal sparing. After re-optimization, all five plans improve in rectal gEUD without clinically considerable deterioration of the PTV D95 value. For the five re-optimized plans, the rectal gEUD is reduced by an average of 1.84 Gray (Gy) with only an average reduction of 0.07 Gy in PTV D95. The results demonstrate that DEA can correctly identify plans with potential improvements in terms of the chosen input and outputs. (paper)

  7. Prospective analysis of patient-reported late toxicity following pelvic radiotherapy for gynaecological cancer

    International Nuclear Information System (INIS)

    Barraclough, Lisa H.; Routledge, Jacqueline A.; Farnell, Damian J.J.; Burns, Meriel P.; Swindell, Ric; Livsey, Jacqueline E.; Davidson, Susan E.

    2012-01-01

    Background and purpose: As late radiotherapy toxicity impacts negatively on the quality-of-life of cancer survivors and is often under reported, a study was set up to prospectively collect patient-reported data in an unselected series of patients with gynaecological malignancy. Aim 1 – To provide 3 year results for the longitudinal study. Aim 2 – To improve the questionnaire used to collect data by identifying redundant items and modifying for use to collect Common Terminology Criteria for Adverse Events (CTCAE) data. Material and methods: Aim 1 – Patient reported outcome data were collected prospectively by 226 patients before and up to 3 years following radiotherapy for gynaecological cancer using a questionnaire developed to collect LENT subjective data. Aim 2 – A factor analysis was performed to identify which questions gave the most and least information. Results: Aim 1 – Faecal urgency and incontinence (all grades) peaked at 79% and 24%, respectively at 1 year then settled to 69% and 18% at 3 years, respectively. Urinary urgency (all grades) increased with time and was described in 75% at 3 years. Other symptoms reported at 3 years include diarrhoea in 12%, urinary incontinence in 27% and vaginal dryness in 29%. A third of patients did not feel their sex life had changed following treatment, while a quarter felt that it had. Aim 2 – some questions overlapped and others were non-specific. The questionnaire has subsequently been altered. Conclusions: The extent of late toxicity is substantial. This detailed information is important for both patients and clinicians in terms of treatment decisions and follow-up care. The LENT questionnaire provides a feasible tool for capture of this information in the clinic.

  8. Analysis of acute and late toxicity of adjuvant radiotherapy in women with cervical and endometrial cancer

    International Nuclear Information System (INIS)

    Warenczak-Florczak, Z.; Roszak, A.; Wlodarczyk, H.; Wojciechowska-Lacka, A.

    2011-01-01

    Background: In case of pure prognostic factors women with cervical and endometrial cancer after surgical operation need to be treated with radiotherapy . Every radiation treatment may be involved with toxicity, acute and late. Material and methods: Performed was detailed analysis of 173 patients with cervical (38) and endometrial (135) cancer. We evaluated early and late post radiation reactions in all patients. Results: Acute reactions were found in 48.5% and late toxicity was found in 9.8% of patients. Women with endometrial cancer were significantly older then patients with cervical cancer (p < 0.002). Higher percentage of acute and late toxicity was observed from the bowel tah urinary tract (26% and 22.5% - acute; 8.1% and 1.73% - late). Higher percentage of acute side effects was observed in patients with cervical than with endometrial cancer (60.5% and 33.7%). Late post radiation reaction predominate also in patient with cervical cancer (13.2% and 8.9%). The adverse effects were associated with prolonged time of treatment due to breaks in radiotherapy. Higher percentage of breaks was found in older patients, more frequent in patient with endometrial than in cervical cancer group (7.4% and 2.6%).To conclude early postradiation reaction appeared more frequently, than late post radiation reactions. It was stated that early and late post radiation reaction appear more frequently in women with cervical than in endometrial cancer. Interruption in radiation delivery was longer than seven days in group with endometrial cancer that leads to extension of complete radiation treatment. (authors)

  9. Evaluation of thyroid gland as an organ at risk after breast cancer radiotherapy: a systematic review and meta-analysis.

    Science.gov (United States)

    Darvish, L; Ghorbani, M; Teshnizi, S Hosseini; Roozbeh, N; Seif, F; Bayatiani, M Reza; Knaup, C; Amraee, A

    2018-05-14

    Radiotherapy can often lead to thyroid dysfunction. Some studies demonstrated that treatment of breast cancer by RT can expose thyroid gland to high doses of radiation. The aim of this systematic review is to evaluate consideration of thyroid gland as an organ at risk. In this systematic review and meta-analysis to select initial studies, a comprehensive search by two independent reviewers was performed. Electronical databases following: Web of Science, Google Scholar, Scopus, PubMed, Elsevier, Embase, ProQuest and Persian databases such as Iranmedex, Magiran, and SID were searched. All searches were restricted to English language between 1985 and 2017. A random effect meta-analysis is applied to estimate pooled effect size across initial studies. Funnel plot with Egger's test is used to assess potential publication bias. Totally, five studies (478 samples) were included in meta-analysis. The meta-analyses of result showed that thyroid gland is affected by radiotherapy significantly and the TSH increased after radiotherapy (z = 2.68, P = 0.007). The pooled estimate of difference mean for TSH was 0.90 (95% CI 0.24, 1.55). In studies among patients with breast cancer RT, hypothyroidism was reported more than other thyroid disorders. There was not showed possibility publication bias among studies (P > 0.05). This study demonstrated that thyroid gland is affected by radiotherapy significantly and the TSH increased after radiotherapy. Protecting thyroid gland during radiation and follow-up of patients with breast cancer RT are suggested for the assessment of thyroid gland dysfunction.

  10. Radiation-induced esophagitis in local advanced non-small cell lung cancer after three-dimensional conformal radiotherapy

    International Nuclear Information System (INIS)

    Tian Dandan; Wang Yuxiang; Qiu Rong; Zhu Shuchai; Tian Xiuming; Qiao Xueying

    2014-01-01

    Objective: To explore radiation-induced esophagitis and its related factors in the patients with local advanced non-small cell lung cancer (NSCLC) which were treated with three-dimensional conformal radiation therapy (3D-CRT). Methods: From January 2001 to December 2008, 203 patients who suffered from stage Ⅲ NSCLC were achieved, including 163 males and 40 females, with a median age of 63 years old, while 79 cases were in stage Ⅲ_a and 124 in stage Ⅲ_b. The equivalent median dose of tumor was 62 Gy(range of 50-78 Gy). Among them, 74 cases were administered with radiotherapy alone, 45 with sequential radiotherapy and chemotherapy, 87 cases with concurrent radiochemotherapy. Radiation esophagitis was evaluated with RTOG standard. The dosimetric parameters was estimated from dose volume histogrma (DVH). The clinical and dosimetric parameters of radiation esophagitis were evaluated by spearman correlatived univariate and Logistic multivariable analysis.Results After radiotherapy, out of 203 patients, 87 had acute radiation esophagitis(RE), 47 in grade 1, 37 in grade 2, and 3 in grade 3 RE. According to spearman correlatived analysis, the correlatived factors included ages, chemotherapy, GTV, PTV, the mean doses of PTV and lung, the max and mean dose of esophagus, V_4_0, V_4_5, V_5_0, V_5_5, V_6_0, length of esophagus (total circumference) treated with 45 Gy (LETT_4_5), and LETT_5_0 (r = -0.162-0.235, P 0.05). There were 21 factors, such as gender, age, smoking, clinical stage, site of tumor, chemotherapy, GTV, PTV, mean dose of PTV and lung, max and mean dose of esophagus, V_4_0-V_6_0 of esophagus, LETT_4_5_-_6_0, incorporated into multivariable analysis, only chemotherapy and V_4_5 of esophagus were independent predicted factors(Wald = 4.626, 9.882, P < 0.05). Conclusions: In local advanced NSCLC after 3D-CRT, chemotherapy(especially concurrent radiochemotherapy) could increase radiation-induced esophagitis. The parameter of DVH could also be used to predict

  11. Artificial neural network analysis applied to simplifying bioeffect radiotherapy treatment planning

    International Nuclear Information System (INIS)

    Purnomo, A.B.

    2001-01-01

    Full text: A bioeffect planning system has been developed by Wigg and Nicholls in the Departments of Clinical Radiobiology and Medical Physics, at the Royal Adelaide Hospital. The system has been developed to be an experimental tool by means of which bioeffect plans may be compared with conventional isodose plans in radiotherapy. Limitations of isodose planning, in many common clinical circumstances, have been apparent for sometime (Wigg and Wilson, Australasian Radiology, 1981, 25: 205-212). There are many reasons why bioeffect planning has been slow in developing. These include concerns about the clinical application of theoretical radiobiology models, the uncertainty of normal tissue and tumour parameter values, and the non-availability of suitable computer systems capable of performing bioeffect planning. These concerns are fully justified and isodose planning must remain, for the foreseeable future, the gold standard for clinical treatment. However, these concerns must be judged against the certainty that isodose planning, in which the only variable usually considered is the total dose, can be substantially misleading. Unfortunately, a typical Tumour Control Probability (TCP) equation for bioeffect planning is complex with 12 parameters. Consequently, the equation is difficult to implement in practice. Can the equation be simplified by ignoring the variability of some of the parameters? To test this possibility, we have attempted a neural network analysis of the problem. The capability of artificial neural network (ANN) analysis to solve classification problems was explored in which a weight space analysis was conducted. It led to the reduction of the number of parameters. The training data for the ANN analysis was generated using the above equation and practical data from many publications. The performance of the optimized ANN and the reduced-parameter ANN were tested using other treatment data. The optimized ANN results closely matched with those of the

  12. Acoustic analysis after radiotherapy in T1 vocal cord carcinoma: a new approach to the analysis of voice quality

    International Nuclear Information System (INIS)

    Rovirosa, Angeles; Martinez-Celdran, Eugenio; Ortega, Alicia; Ascaso, Carlos; Abellana, Rosa; Velasco, Mercedes; Bonet, Montserrat; Herrera, Carmen; Casas, Francesc; Francisco, Rosa Maria; Arenas, Meritxell; Hernandez, Victor; Sanchez-Reyes, Alberto; Leon, Concha; Traserra, Jordi; Biete, Albert

    2000-01-01

    Purpose: The study of acoustic voice parameters (fundamental frequency, jitter, shimmer, and harmonics-to-noise ratio) in extended vowel production, oral reading of a standard paragraph, spontaneous speech and a song in irradiated patients for Tis-T1 vocal cord carcinoma. Methods and Materials: Eighteen male patients irradiated for Tis-T1 vocal cord carcinoma and a control group of 31 nonirradiated subjects of the same age were included in a study of acoustic voice analysis. The control group had been rigorously selected for voice quality and the irradiated group had previous history of smoking in two-thirds of the cases and a vocal cord biopsy. Radiotherapy patients were treated with a 6MV Linac receiving a total dose of 66 Gy, 2 Gy/day, with median treatment areas of 28 cm 2 . Acoustic voice analysis was performed 1 year after radiotherapy, the voice of patients in extended vowel production, oral reading of a standard paragraph, spontaneous speech, and in a song was tape registered and analyzed by a Kay Elemetric's Computerized Speech Lab (model CSL no. 4300). Fundamental frequency, jitter, shimmer, and harmonics-to-noise ratio were obtained in each case. Mann Whitney analysis was used for statistical tests. Results: The irradiated group presented higher values of fundamental frequency, jitter, shimmer, and harmonics-to-noise ratio. Mann-Whitney analysis showed significant differences for fundamental frequency and jitter in vowel production, oral reading, spontaneous speech, and song. Shimmer only showed differences in vowel production and harmonics-to-noise ratio in oral reading and song. Conclusions: In our study only fundamental frequency and jitter showed significant increased values to the control group in all the acoustic situations. Sustained vowel production showed the worst values of the acoustic parameters in comparison with the other acoustic situations. This study seems to suggest that more work should be done in this field

  13. Texture analysis for the assessment of structural changes in parotid glands induced by radiotherapy

    International Nuclear Information System (INIS)

    Scalco, Elisa; Fiorino, Claudio; Cattaneo, Giovanni Mauro; Sanguineti, Giuseppe; Rizzo, Giovanna

    2013-01-01

    Background and purpose: During radiotherapy (RT) for head-and-neck cancer, parotid glands undergo significant anatomic, functional and structural changes which could characterize pre-clinical signs of an increased risk of xerostomia. Texture analysis is proposed to assess structural changes of parotids induced by RT, and to investigate whether early variations of textural parameters (such as mean intensity and fractal dimension) can predict parotid shrinkage at the end of treatment. Material and methods: Textural parameters and volumes of 42 parotids from 21 patients treated with intensity-modulated RT for nasopharyngeal cancer were extracted from CT images. To individuate which parameters changed during RT, a Wilcoxon signed-rank test between textural indices (first and second RT week; first and last RT week) was performed. Discriminant analysis was applied to variations of these parameters in the first two weeks of RT to assess their power in predicting parotid shrinkage at the end of RT. Results: A significant decrease in mean intensity (1.7 HU and 3.8 HU after the second and last weeks, respectively) and fractal dimension (0.016 and 0.021) was found. Discriminant analysis, based on volume and fractal dimension, was able to predict the final parotid shrinkage (accuracy of 71.4%). Conclusion: Textural features could be used in combination with volume to characterize structural modifications on parotid glands and to predict parotid shrinkage at the end of RT

  14. Interindividual registration and dose mapping for voxelwise population analysis of rectal toxicity in prostate cancer radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Dréan, Gaël; Acosta, Oscar, E-mail: Oscar.Acosta@univ-rennes1.fr; Simon, Antoine; Haigron, Pascal [INSERM, U1099, Rennes F-35000 (France); Université de Rennes 1, LTSI, Rennes F-35000 (France); Lafond, Caroline; Crevoisier, Renaud de [INSERM, U1099, Rennes F-35000 (France); Université de Rennes 1, LTSI, Rennes F-35000 (France); Département de Radiothérapie, Center Eugène Marquis, Rennes F-35000 (France)

    2016-06-15

    Purpose: Recent studies revealed a trend toward voxelwise population analysis in order to understand the local dose/toxicity relationships in prostate cancer radiotherapy. Such approaches require, however, an accurate interindividual mapping of the anatomies and 3D dose distributions toward a common coordinate system. This step is challenging due to the high interindividual variability. In this paper, the authors propose a method designed for interindividual nonrigid registration of the rectum and dose mapping for population analysis. Methods: The method is based on the computation of a normalized structural description of the rectum using a Laplacian-based model. This description takes advantage of the tubular structure of the rectum and its centerline to be embedded in a nonrigid registration-based scheme. The performances of the method were evaluated on 30 individuals treated for prostate cancer in a leave-one-out cross validation. Results: Performance was measured using classical metrics (Dice score and Hausdorff distance), along with new metrics devised to better assess dose mapping in relation with structural deformation (dose-organ overlap). Considering these scores, the proposed method outperforms intensity-based and distance maps-based registration methods. Conclusions: The proposed method allows for accurately mapping interindividual 3D dose distributions toward a single anatomical template, opening the way for further voxelwise statistical analysis.

  15. Intensity modulated radiotherapy for localized prostate cancer: rigid compliance to dose-volume constraints as a warranty of acceptable toxicity?

    International Nuclear Information System (INIS)

    Chen, Michael J; Nadalin, Wladmir; Weltman, Eduardo; Hanriot, Rodrigo M; Luz, Fábio P; Cecílio, Paulo J; Cruz, José C da; Moreira, Frederico R; Santos, Adriana S; Martins, Lidiane C

    2007-01-01

    To report the toxicity after intensity modulated radiotherapy (IMRT) for patients with localized prostate cancer, as a sole treatment or after radical prostatectomy. Between August 2001 and December 2003, 132 patients with prostate cancer were treated with IMRT and 125 were evaluable to acute and late toxicity analysis, after a minimum follow-up time of one year. Clinical and treatment data, including normal tissue dose-volume histogram (DVH) constraints, were reviewed. Gastro-intestinal (GI) and genito-urinary (GU) signs and symptoms were evaluated according to the Radiation Therapy Oncology Group (RTOG) toxicity scales. Median prescribed dose was 76 Gy. Median follow-up time was of 26.1 months. From the 125 patients, 73 (58.4%) presented acute Grade 1 or Grade 2 GI and 97 (77.2%) presented acute Grade 1 or Grade 2 GU toxicity. Grade 3 GI acute toxicity occurred in only 2 patients (1.6%) and Grade 3 GU acute toxicity in only 3 patients (2.4%). Regarding Grade 1 and 2 late toxicity, 26 patients (20.8%) and 21 patients (16.8%) presented GI and GU toxicity, respectively. Grade 2 GI late toxicity occurred in 6 patients (4.8%) and Grade 2 GU late toxicity in 4 patients (3.2%). None patient presented any Grade 3 or higher late toxicity. Non-conformity to DVH constraints occurred in only 11.2% of treatment plans. On univariate analysis, no significant risk factor was identified for Grade 2 GI late toxicity, but mean dose delivered to the PTV was associated to higher Grade 2 GU late toxicity (p = 0.042). IMRT is a well tolerable technique for routine treatment of localized prostate cancer, with short and medium-term acceptable toxicity profiles. According to the data presented here, rigid compliance to DHV constraints might prevent higher incidences of normal tissue complication

  16. Poster — Thur Eve — 69: Computational Study of DVH-guided Cancer Treatment Planning Optimization Methods

    Energy Technology Data Exchange (ETDEWEB)

    Ghomi, Pooyan Shirvani; Zinchenko, Yuriy [University of Calgary, Department of Mathematics and Statistics (Canada)

    2014-08-15

    Purpose: To compare methods to incorporate the Dose Volume Histogram (DVH) curves into the treatment planning optimization. Method: The performance of three methods, namely, the conventional Mixed Integer Programming (MIP) model, a convex moment-based constrained optimization approach, and an unconstrained convex moment-based penalty approach, is compared using anonymized data of a prostate cancer patient. Three plans we generated using the corresponding optimization models. Four Organs at Risk (OARs) and one Tumor were involved in the treatment planning. The OARs and Tumor were discretized into total of 50,221 voxels. The number of beamlets was 943. We used commercially available optimization software Gurobi and Matlab to solve the models. Plan comparison was done by recording the model runtime followed by visual inspection of the resulting dose volume histograms. Conclusion: We demonstrate the effectiveness of the moment-based approaches to replicate the set of prescribed DVH curves. The unconstrained convex moment-based penalty approach is concluded to have the greatest potential to reduce the computational effort and holds a promise of substantial computational speed up.

  17. Radiotherapy physics

    International Nuclear Information System (INIS)

    Chen, G.T.Y.; Collier, J.M.; Lyman, J.T.; Pitluck, S.

    1982-01-01

    The Radiotherapy Physics Group works on the physical and biophysical aspects of charged particle radiotherapy. Our activities include the development of isosurvival beams (beams of uniform biological effect), computerized treatment planning development for charged particle radiotherapy, design of compensation to shape dose distributions, and development of dosimetry techniques to verify planned irradiations in both phantoms and patients

  18. Single-arc volumetric-modulated arc therapy (sVMAT) as adjuvant treatment for gastric cancer: Dosimetric comparisons with three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT)

    International Nuclear Information System (INIS)

    Wang, Xin; Li, Guangjun; Zhang, Yingjie; Bai, Sen; Xu, Feng; Wei, Yuquan; Gong, Youling

    2013-01-01

    To compare the dosimetric differences between the single-arc volumetric-modulated arc therapy (sVMAT), 3-dimensional conformal radiotherapy (3D-CRT), and intensity-modulated radiotherapy (IMRT) techniques in treatment planning for gastric cancer as adjuvant radiotherapy. Twelve patients were retrospectively analyzed. In each patient's case, the parameters were compared based on the dose-volume histogram (DVH) of the sVMAT, 3D-CRT, and IMRT plans, respectively. Three techniques showed similar target dose coverage. The maximum and mean doses of the target were significantly higher in the sVMAT plans than that in 3D-CRT plans and in the 3D-CRT/IMRT plans, respectively, but these differences were clinically acceptable. The IMRT and sVMAT plans successfully achieved better target dose conformity, reduced the V 20/30 , and mean dose of the left kidney, as well as the V 20/30 of the liver, compared with the 3D-CRT plans. And the sVMAT technique reduced the V 20 of the liver much significantly. Although the maximum dose of the spinal cord were much higher in the IMRT and sVMAT plans, respectively (mean 36.4 vs 39.5 and 40.6 Gy), these data were still under the constraints. Not much difference was found in the analysis of the parameters of the right kidney, intestine, and heart. The IMRT and sVMAT plans achieved similar dose distribution to the target, but superior to the 3D-CRT plans, in adjuvant radiotherapy for gastric cancer. The sVMAT technique improved the dose sparings of the left kidney and liver, compared with the 3D-CRT technique, but showed few dosimetric advantages over the IMRT technique. Studies are warranted to evaluate the clinical benefits of the VMAT treatment for patients with gastric cancer after surgery in the future

  19. Effectiveness of surgery and individualized high-dose hyperfractionated accelerated radiotherapy on survival in clinical stage I non-small cell lung cancer. A propensity score matched analysis

    International Nuclear Information System (INIS)

    Jimenez, Marcelo F.; Baardwijk, Angela van; Aerts, Hugo J.W.L.; De Ruysscher, Dirk; Novoa, Nuria M.; Varela, Gonzalo; Lambin, Philippe

    2010-01-01

    Background and purpose: Surgery is considered the treatment of choice for early-stage non-small cell lung cancer (NSCLC). Patients with poor pulmonary function or other comorbidities are treated with radiotherapy. The objective of this investigation is to compare the 3-year survival of two early-stage NSCLC populations treated in two different hospitals, either by surgical resection (lobectomy) or by individualized high-dose accelerated radiotherapy, after matching patients by propensity scoring analysis. Methods: A retrospective comparative study has been performed on two series of consecutive patients with cytohistological diagnosis of NSCLC, clinically staged IA by means of PET-scan (radiotherapy group) and pathologically staged IA (surgery group). Results: A total of 157 cases were initially selected for the analysis (110 operated and 47 treated by radiotherapy). Patients in the radiotherapy group were older, with higher comorbidity and lower FEV1% with 3-years probability of survival for operated patients higher than that found for patients treated by radiotherapy. After matching by propensity scoring (using age and FEV1%), differences disappear and 3-years probability of survival had no statistical differences. Conclusions: Although this is a non-randomized retrospective analysis, we have not found 3-years survival differences after matching cases between surgery and radiotherapy. Nevertheless, data presented here support the continuous investigation for non-surgical alternatives in this disease.

  20. 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

  1. Patterns of local-regional failure after primary intensity modulated radiotherapy for nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Kong, Fangfang; Ying, Hongmei; Du, Chengrun; Huang, Shuang; Zhou, Junjun; Chen, Junchao; Sun, Lining; Chen, Xiaohui; Hu, Chaosu

    2014-01-01

    To analyze patterns of local-regional failure after primary intensity modulated radiotherapy (IMRT) for nasopharyngeal carcinoma (NPC). A total of 370 non-metastatic NPC patients consecutively treated with IMRT (with or without chemotherapy) were analyzed. Radiotherapy was administered using a simultaneous integrated boost (SIB) technique at the total prescribed dose of 66-70.4Gy (2.0-2.2Gy per fraction). The location and extent of local-regional failures were transferred to the pretreatment planning computed tomography (CT) for dosimetric analysis. The dose of radiation received by V recur (volume of recurrence) was calculated and analyzed with dose-volume histogram (DVH). Failures were classified as: 'in field' if 95% of V recur was within the 95% isodose, 'marginal' if 20% to 95% of V recur was within the 95% isodose, or 'outside' if less than 20% of V recur was inside the 95% isodose. With a median follow up of 26 months, 25 local-regional failures were found in 18 patients. The 1- and 2-year actuarial local-regional control rates for all patients were 99.7% and 95.5% respectively. Among the 22 local–regional failures with available diagnostic images, 16 (64%) occurred within the 95% isodose lines and were considered in-field failures; 3 (12%) were marginal and 3 (12%) were outside-field failures. Intensity-modulated radiotherapy provides excellent local-regional control for NPC. In-field failures are the main patterns for local-regional recurrence. Reducing the coverage of critical adjacent tissues in CTV purposefully for potential subclinical diseases was worth of study. Great attention in all IMRT steps is necessary to reduce potential causes of marginal failures. More studies about radioresistance are needed to reduce in-field failures

  2. Stereotactic radiotherapy and radiosurgery in pediatric patients: analysis of indications and outcome

    DEFF Research Database (Denmark)

    Mirza, Bilal; Mønsted, Anne; Jensen, Josephine Harding

    2010-01-01

    We describe indications, outcomes, and risk profiles of fractionated stereotactic radiotherapy (SRT) and single fraction "radiosurgery" (SRS) in pediatric patients compared to the adult population and evaluate the causal role of SRS and SRT in inducing new neurological complications....

  3. The role of radiotherapy in the management of extrahepatic bile duct cancer: an analysis of 145 consecutive patients treated with intraluminal and/or external beam radiotherapy

    International Nuclear Information System (INIS)

    Kamada, Tadashi; Saitou, Hiroya; Takamura, Akio; Nojima, Takayuki; Okushiba, Shun-Ichi

    1996-01-01

    Purpose: To determine the feasibility of high dose radiotherapy and to evaluate its role in the management of extrahepatic bile duct (EHBD) cancer. Methods and Materials: Between 1983 and 1991, 145 consecutive patients with EHBD cancer were treated by low dose rate intraluminal 192 Ir irradiation (ILRT) either alone or in combination with external beam radiotherapy (EBRT). Among the primarily irradiated, 77 patients unsuitable for surgical resection, 54 were enrolled in radical radiotherapy, and 23 received palliative radiotherapy. Fifty-nine received postoperative radiotherapy, and the remaining 9 preoperative radiotherapy. The mean radiation dose was 67.8 Gy, ranging from 10 to 135 Gy. Intraluminal 192 Ir irradiation was indicated in 103 patients, and 85 of them were combined with EBRT. Expandable metallic biliary endoprosthesis (EMBE) was used in 32 primarily irradiated patients (31 radical and 1 palliative radiotherapy) after the completion of radiotherapy. Results: The 1-, 3-, and 5-year actuarial survival rates for all 145 patients were 55%, 18%, and 10%, for the 54 patients treated by radical radiotherapy (mean 83.1 Gy), 56%, 13%, and 6% [median survival time (MST) 12.4 months], and for the 59 patients receiving postoperative radiotherapy (mean 61.6 Gy), 73%, 31%, and 18% (MST 21.5 months), respectively. Expandable metallic biliary endoprosthesis was useful for the early establishment of an internal bile passage in radically irradiated patients and MST of 14.9 months in these 31 patients was significantly longer than that of 9.3 months in the remaining 23 patients without EMBE placement (p < 0.05). Eighteen patients whose surgical margins were positive in the hepatic side bile duct(s) showed significantly better survival compared with 15 patients whose surgical margins were positive in the adjacent structure(s) (44% vs. 0% survival at 3 years, p < 0.001). No survival benefit was obtained in patients given palliative or preoperative radiotherapy

  4. Analysis of the testicular dose in patients undergoing radiotherapy for carcinoma of the prostate

    International Nuclear Information System (INIS)

    Bejar Navarro, M. J.; Ordonez Marquez, J.; Hervas Moron, A.; Alvarez Rodriguez, S.; Garcia-Galloway, E.; Sanchez Casanueva, R.; Polo Rubio, A.; Rodriguez-Patron, R.; Yanowsky, K.; Gomez Dos Santos, V.

    2013-01-01

    The objectives of this work are: -Studying comparatively the doses received in testes in patients undergoing radiotherapy of prostate carcinoma with external beam radiation and brachytherapy of low rate using I-125 seeds. -Compare doses due to images of verification using Cone Beam CT (CBCT), with doses of radiotherapy treatment itself. -Determine the seminal alterations and cytogenetic after treatment with ionizing radiation (RTE or BQT) in patients diagnosed with prostate cancer and its relation with testicular dose. (Author)

  5. Inspection of the brazilian nuclear regulatory body in the area of radiotherapy. A critical analysis

    International Nuclear Information System (INIS)

    Brito, Ricardo Roberto de Azevedo

    2005-01-01

    The National Commission of Nuclear Energy (CNEN) is responsible in Brazil for the activities of licensing and control of radioactive installations in the radiotherapy medical area. The majority of these activities are developed by CNEN Co-ordination of Radioactive Installations (CORAD). One of the necessary stages for the development of licensing and control activities is the inspection of radiotherapy services (clinics and hospitals). Almost all of these inspections are carried out by CNEN Inst. of Radiation Protection and Dosimetry (IRD), through its Service of Medical Physics in Radiotherapy and Nuclear Medicine (SEFME). This work makes a survey of the main nonconformities found during ten years of inspections in radiotherapy services (1995 - 2004) and analyses the efficiency of these inspections in making the radiotherapy services develop their activities according to the norms in vigour in the country and adopt corrective actions against, at least, the nonconformities evidenced by CNEN inspectors. Additionally, it analyses the possibility of improvement and / or the optimisation of the process, through a procedure able to be unified and controlled, aiming a prompt communication to those involved in the licensing process (SEFME and CORAD) about the attendance by the radiotherapy services to the non-conformity items observed during the inspection. (author)

  6. Stability of spinal bone metastases in breast cancer after radiotherapy. A retrospective analysis of 157 cases

    Energy Technology Data Exchange (ETDEWEB)

    Schlampp, Ingmar; Rieken, Stefan; Habermehl, Daniel; Foerster, Robert; Debus, Juergen; Rief, Harald [University Hospital of Heidelberg, Department of Radiation Oncology, Heidelberg (Germany); Bruckner, Thomas [University Hospital of Heidelberg, Department of Medical Biometry, Heidelberg (Germany)

    2014-09-15

    This retrospective analysis was performed to evaluate osteolytic bone lesions of breast cancer in the thoracic and lumbar spine after radiotherapy (RT) in terms of stability using a validated scoring system. The stability of 157 osteolytic metastases, treated from January 2000 to January 2012, in 115 patients with breast cancer was evaluated retrospectively using the Taneichi score. Predictive factors for stability were analyzed and survival rates were calculated. Eighty-five (54 %) lesions were classified as unstable prior to RT. After 3 and 6 months, 109 (70 %) and 124 (79 %) lesions, respectively, were classified as stable. Thirty fractures were detected prior to RT, and after RT seven cases (4.5 %) with pathologic fractures were found within 6 months. None of the examined predictive factors showed significant correlation with stability 6 months after RT. After a median follow-up of 16.7 months, Kaplan-Meier estimates revealed an overall survival of 83 % after 5 years. The majority of patients showed an improved or unchanged stability of the involved vertebral bodies after 6 months. The patients showed only minor cancer-related morbidity during follow-up and reached comparably high survival rates. (orig.) [German] Die retrospektive Analyse untersuchte osteolytische Knochenmetastasen von Patienten mit Mammakarzinom der thorakalen und lumbalen Wirbelsaeule nach Radiotherapie (RT) hinsichtlich Stabilitaet anhand eines validierten Scores. Die Stabilitaet von 157 osteolytischen Metastasen bei 115 Patienten mit Brustkrebs, behandelt von Januar 2000 bis Januar 2012, wurde retrospektiv anhand des Taneichi-Scores evaluiert. Prognostische Faktoren bezueglich Stabilitaet und Ueberlebensraten wurden analysiert. Vor RT wurden 85 Laesionen (54 %) als instabil gewertet. Nach 3 und 6 Monaten wurden 109 (70 %) und 124 (79 %) Laesionen als stabil klassifiziert. Vor RT wurden 30 Frakturen gefunden, nach RT zeigten sich 7 weitere (4,5 %) pathologische Frakturen. Kein prognostischer

  7. A meta-analysis of hyperfractionated and accelerated radiotherapy and combined chemotherapy and radiotherapy regimens in unresected locally advanced squamous cell carcinoma of the head and neck

    International Nuclear Information System (INIS)

    Budach, W; Hehr, T; Budach, V; Belka, C; Dietz, K

    2006-01-01

    Former meta-analyses have shown a survival benefit for the addition of chemotherapy (CHX) to radiotherapy (RT) and to some extent also for the use of hyperfractionated radiation therapy (HFRT) and accelerated radiation therapy (AFRT) in locally advanced squamous cell carcinoma (SCC) of the head and neck. However, the publication of new studies and the fact that many older studies that were included in these former meta-analyses used obsolete radiation doses, CHX schedules or study designs prompted us to carry out a new analysis using strict inclusion criteria. Randomised trials testing curatively intended RT (≥60 Gy in >4 weeks/>50 Gy in <4 weeks) on SCC of the oral cavity, oropharynx, hypopharynx, and larynx published as full paper or in abstract form between 1975 and 2003 were eligible. Trials comparing RT alone with concurrent or alternating chemoradiation (5-fluorouracil (5-FU), cisplatin, carboplatin, mitomycin C) were analyzed according to the employed radiation schedule and the used CHX regimen. Studies comparing conventionally fractionated radiotherapy (CFRT) with either HFRT or AFRT without CHX were separately examined. End point of the meta-analysis was overall survival. Thirty-two trials with a total of 10 225 patients were included into the meta-analysis. An overall survival benefit of 12.0 months was observed for the addition of simultaneous CHX to either CFRT or HFRT/AFRT (p < 0.001). Separate analyses by cytostatic drug indicate a prolongation of survival of 24.0 months, 16.8 months, 6.7 months, and 4.0 months, respectively, for the simultaneous administration of 5-FU, cisplatin-based, carboplatin-based, and mitomycin C-based CHX to RT (each p < 0.01). Whereas no significant gain in overall survival was observed for AFRT in comparison to CFRT, a substantial prolongation of median survival (14.2 months, p < 0.001) was seen for HFRT compared to CFRT (both without CHX). RT combined with simultaneous 5-FU, cisplatin, carboplatin, and mitomycin C as

  8. Evaluation of a post-analysis method for cumulative dose distribution in stereotactic body radiotherapy

    International Nuclear Information System (INIS)

    Imae, Toshikazu; Takenaka, Shigeharu; Saotome, Naoya

    2016-01-01

    The purpose of this study was to evaluate a post-analysis method for cumulative dose distribution in stereotactic body radiotherapy (SBRT) using volumetric modulated arc therapy (VMAT). VMAT is capable of acquiring respiratory signals derived from projection images and machine parameters based on machine logs during VMAT delivery. Dose distributions were reconstructed from the respiratory signals and machine parameters in the condition where respiratory signals were without division, divided into 4 and 10 phases. The dose distribution of each respiratory phase was calculated on the planned four-dimensional CT (4DCT). Summation of the dose distributions was carried out using deformable image registration (DIR), and cumulative dose distributions were compared with those of the corresponding plans. Without division, dose differences between cumulative distribution and plan were not significant. In the condition Where respiratory signals were divided, dose differences were observed over dose in cranial region and under dose in caudal region of planning target volume (PTV). Differences between 4 and 10 phases were not significant. The present method Was feasible for evaluating cumulative dose distribution in VMAT-SBRT using 4DCT and DIR. (author)

  9. Results of radiotherapy in recurrent endometrial carcinoma: A retrospective analysis of 51 patients

    International Nuclear Information System (INIS)

    Kuten, A.; Grigsby, P.W.; Perez, C.A.; Fineberg, B.; Garcia, D.M.; Simpson, J.R.

    1989-01-01

    A retrospective analysis was performed of 51 patients with locoregional recurrence of endometrial carcinoma, treated by radiotherapy between 1959 and 1986. There were 17 patients (33%) with isolated vaginal recurrence, 12 patients (24%) with vaginal recurrence with pelvic extension, 7 patients (14%) with pelvic recurrence only, and 15 patients (29%) with simultaneous locoregional and distant failure. Eighty percent of the recurrences occurred within 3.5 years from primary treatment; time to relapse was shorter in patients with advanced-stage, high-grade malignancy at original diagnosis. Locoregional control was achieved in 18 patients (35%). Complete tumor regression in the vagina, irrespective of extravaginal pelvic disease status or distant metastasis, occurred in 28 of 34 patients with vaginal involvement (82%). The 5- and 10-year overall actuarial survivals for all patients were 18 and 12.5%, respectively. The 5- and 10-year progression-free survivals of patients with isolated vaginal recurrences were 40% and 29%, respectively; the 5-year progression-free survival of patients with vaginal recurrence with pelvic extension was 20%. There were no survivors beyond 1.5 years among patients with pelvic recurrence (p = 0.02). All patients with simultaneous locoregional and distant failure were dead by 3.5 years. Stage at original diagnosis, time to relapse from primary treatment, histologic pattern, and grade of malignancy were prognosticators of survival. Five patients (10%) developed a total of ten radiation-related sequelae

  10. APPLICATION OF IMAGE ANALYSIS METHODS FOR ISOCENTER QUALITY ASSURANCE IN RADIOTHERAPY

    Directory of Open Access Journals (Sweden)

    Michał Niedźwiecki

    2017-03-01

    Full Text Available One of the major procedures for testing the geometrical accuracy of devices used in radiotherapy treatments is the test of the geometrical position of the radiation isocenter. The importance of the test reflects the fact that geometrical position of the radiation isocenter generally affects the tumor targeting. At present the geometric accuracy is assessed with the Winston-Lutz test which checks the position of an image of a ball marker with the respect to the center of the radiation field as projected on a detector plane. Obviously, determination of coordinates of a single marker is not sufficient to fully account for a complicated geometry of a therapeutic device. The purpose of the study was to design a new image analysis tool to better determine the isocenter. The proposed automated procedure for determining isocenter position uses projection data acquired for a special cube phantom. The projection images of a phantom are acquired for various angles of rotation of the gantry. A procedure is proposed to extract some geometric characteristics of a therapeutic device from the projection images.

  11. Clinical and technical characteristics of intraoperative radiotherapy. Analysis of the ISIORT-Europe database

    International Nuclear Information System (INIS)

    Krengli, M.; Sedlmayer, F.

    2013-01-01

    Background: A joint analysis of clinical data from centres within the European section of the International Society of Intraoperative Radiation Therapy (ISIORT-Europe) was undertaken in order to define the range of intraoperative radiotherapy (IORT) techniques and indications encompassed by its member institutions. Materials and methods: In 2007, the ISIORT-Europe centres were invited to record demographic, clinical and technical data relating to their IORT procedures in a joint online database. Retrospective data entry was possible. Results: The survey encompassed 21 centres and data from 3754 IORT procedures performed between 1992 and 2011. The average annual number of patients treated per institution was 42, with three centres treating more than 100 patients per year. The most frequent tumour was breast cancer with 2395 cases (63.8 %), followed by rectal cancer (598 cases, 15.9 %), sarcoma (221 cases, 5.9 %), prostate cancer (108 cases, 2.9 %) and pancreatic cancer (80 cases, 2.1 %). Clinical details and IORT technical data from these five tumour types are reported. Conclusion: This is the first report on a large cohort of patients treated with IORT in Europe. It gives a picture of patient selection methods and treatment modalities, with emphasis on the main tumour types that are typically treated by this technique and may benefit from it. (orig.)

  12. Interventions for the management of radiotherapy-induced xerostomia and hyposalivation: A systematic review and meta-analysis.

    Science.gov (United States)

    Mercadante, Valeria; Al Hamad, Arwa; Lodi, Giovanni; Porter, Stephen; Fedele, Stefano

    2017-03-01

    Salivary gland hypofunction is a common and permanent adverse effect of radiotherapy to the head and neck. Randomised trials of available treatment modalities have produced unclear results and offer little reliable guidance for clinicians to inform evidence-based therapy. We have undertaken this systematic review and meta-analysis to estimate the effectiveness of available interventions for radiotherapy-induced xerostomia and hyposalivation. We searched MEDLINE, Cochrane Central, EMBASE, AMED, and CINAHL database through July 2016 for randomised controlled trials comparing any topical or systemic intervention to active and/or non-active controls for the treatment of radiotherapy-induced xerostomia. The results of clinically and statistically homogenous studies were pooled and meta-analyzed. 1732 patients from twenty studies were included in the systematic review. Interventions included systemic or topical pilocarpine, systemic cevimeline, saliva substitutes/mouthcare systems, hyperthermic humidification, acupuncture, acupuncture-like transcutaneous electrical nerve stimulation, low-level laser therapy and herbal medicine. Results from the meta-analysis, which included six studies, suggest that both cevimeline and pilocarpine can reduce xerostomia symptoms and increase salivary flow compared to placebo, although some aspects of the relevant effect size, duration of the benefit, and clinical meaningfulness remain unclear. With regard to interventions not included in the meta-analysis, we found no evidence, or very weak evidence, that they can reduce xerostomia symptoms or increase salivary flow in this population. Pilocarpine and cevimeline should represent the first line of therapy in head and neck cancer survivors with radiotherapy-induced xerostomia and hyposalivation. The use of other treatment modalities cannot be supported on the basis of current evidence. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Outcomes of visual acuity in carbon ion radiotherapy: Analysis of dose-volume histograms and prognostic factors

    International Nuclear Information System (INIS)

    Hasegawa, Azusa; Mizoe, Jun-etsu; Mizota, Atsushi; Tsujii, Hirohiko

    2006-01-01

    Purpose: To analyze the tolerance dose for retention of visual acuity in patients with head-and-neck tumors treated with carbon ion radiotherapy. Methods and Materials: From June 1994 to March 2000, 163 patients with tumors in the head and neck or skull base region were treated with carbon ion radiotherapy. Analysis was performed on 54 optic nerves (ONs) corresponding to 30 patients whose ONs had been included in the irradiated volume. These patients showed no evidence of visual impairment due to other factors and had a follow-up period of >4 years. All patients had been informed of the possibility of visual impairment before treatment. We evaluated the dose-complication probability and the prognostic factors for the retention of visual acuity in carbon ion radiotherapy, using dose-volume histograms and multivariate analysis. Results: The median age of 30 patients (14 men, 16 women) was 57.2 years. Median prescribed total dose was 56.0 gray equivalents (GyE) at 3.0-4.0 GyE per fraction per day (range, 48-64 GyE; 16-18 fractions; 4-6 weeks). Of 54 ONs that were analyzed, 35 had been irradiated with max ]) resulting in no visual loss. Conversely, 11 of the 19 ONs (58%) irradiated with >57 GyE (D max ) suffered a decrease of visual acuity. In all of these cases, the ONs had been involved in the tumor before carbon ion radiotherapy. In the multivariate analysis, a dose of 20% of the volume of the ON (D 2 ) was significantly associated with visual loss. Conclusions: The occurrence of visual loss seems to be correlated with a delivery of >60 GyE to 20% of the volume of the ON

  14. A meta-analysis of hyperfractionated and accelerated radiotherapy and combined chemotherapy and radiotherapy regimens in unresected locally advanced squamous cell carcinoma of the head and neck

    Directory of Open Access Journals (Sweden)

    Budach V

    2006-01-01

    Full Text Available Abstract Background Former meta-analyses have shown a survival benefit for the addition of chemotherapy (CHX to radiotherapy (RT and to some extent also for the use of hyperfractionated radiation therapy (HFRT and accelerated radiation therapy (AFRT in locally advanced squamous cell carcinoma (SCC of the head and neck. However, the publication of new studies and the fact that many older studies that were included in these former meta-analyses used obsolete radiation doses, CHX schedules or study designs prompted us to carry out a new analysis using strict inclusion criteria. Methods Randomised trials testing curatively intended RT (≥60 Gy in >4 weeks/>50 Gy in Results Thirty-two trials with a total of 10 225 patients were included into the meta-analysis. An overall survival benefit of 12.0 months was observed for the addition of simultaneous CHX to either CFRT or HFRT/AFRT (p Conclusion RT combined with simultaneous 5-FU, cisplatin, carboplatin, and mitomycin C as single drug or combinations of 5-FU with one of the other drugs results in a large survival advantage irrespective the employed radiation schedule. If radiation therapy is used as single modality, hyperfractionation leads to a significant improvement of overall survival. Accelerated radiation therapy alone, especially when given as split course radiation schedule or extremely accelerated treatments with decreased total dose, does not increase overall survival.

  15. Evaluation of Thyroid Disorders During Head-and-Neck Radiotherapy by Using Functional Analysis and Ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Bakhshandeh, Mohsen [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Hashemi, Bijan, E-mail: bhashemi@modares.ac.ir [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Mahdavi, Seyed Rabie [Department of Medical Physics, Faculty of Medical Sciences, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Nikoofar, Alireza [Department of Radiation Oncology, Hafte-Tir Hospital, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Edraki, Hamid Reza [Department of Radiology, Panzdahe-Khordad Hospital, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Kazemnejad, Anoshirvan [Department of Biostatistics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of)

    2012-05-01

    Purpose: To evaluate thyroid function and vascular changes during radiotherapy for patients with head and neck cancer. Methods and Materials: Fifty patients treated with primary or postoperative radiotherapy for various cancers in the head and neck region were prospectively evaluated. The serum samples (triiodothyronine [T3], thyroxine [T4], thyroid-stimulating hormone [TSH], free triiodothyronine [FT3], and free thyroxine [FT4]), the echo level of the thyroid gland, and color Doppler ultrasonography (CDU) parameters of the right inferior thyroid artery (RITA) of the patients were measured before and at regular intervals during radiotherapy. The thyroid gland dose-volume histograms of the patients were derived from their computed tomography-based treatment plans. Results: There was a significant fall in TSH level (p < 0.0001) but an increase in FT4 (p < 0.0001) and T4 (p < 0.022) levels during the radiotherapy course. The threshold dose required to produce significant changes was 12 Gy (Biologically Effective Dose in 2-Gy fractions, BED{sub 2}). There were significant rises in the patients' pulsatility index, resistive index, peak systolic velocity, blood volume flow levels, and RITA diameter (p < 0.0001), as detected by CDU during radiotherapy, compared to those parameters measured before the treatment. Hypoechogenicity and irregular echo patterns (p < 0.0001) were seen during radiotherapy compared to those before treatment. There was significant Pearson's correlation between the CDU parameters and T4, FT4, and TSH levels. Conclusions: Radiation-induced thyroiditis is regarded as primary damage to the thyroid gland. Thyroiditis can subsequently result in hypothyroidism or hyperthyroidism. Our results demonstrated that changes in thyroid vessels occur during radiotherapy delivered to patients. Vessel changes also can be attributed to the late effect of radiation on the thyroid gland. The hypoechogenicity and irregular echo patterns observed in patients

  16. Dose-volume histogram analysis as predictor of radiation pneumonitis in primary lung cancer patients treated with radiotherapy

    International Nuclear Information System (INIS)

    Fay, Michael; Tan, Alex; Fisher, Richard; Mac Manus, Michael; Wirth, Andrew; Ball, David

    2005-01-01

    Purpose: To determine the relationship between various parameters derived from lung dose-volume histogram analysis and the risk of symptomatic radiation pneumonitis (RP) in patients undergoing radical radiotherapy for primary lung cancer. Methods and Materials: The records of 156 patients with lung cancer who had been treated with radical radiotherapy (≥45 Gy) and for whom dose-volume histogram data were available were reviewed. The incidence of symptomatic RP was correlated with a variety of parameters derived from the dose-volume histogram data, including the volume of lung receiving 10 Gy (V 10 ) through 50 Gy (V 50 ) and the mean lung dose (MLD). Results: The rate of RP at 6 months was 15% (95% confidence interval 9-22%). On univariate analysis, only V 30 (p = 0.036) and MLD (p = 0.043) were statistically significantly related to RP. V 30 correlated highly positively with MLD (r = 0.96, p 30 and MLD can be used to predict the risk of RP in lung cancer patients undergoing radical radiotherapy

  17. Pelvic Insufficiency Fracture After Pelvic Radiotherapy for Cervical Cancer: Analysis of Risk Factors

    International Nuclear Information System (INIS)

    Oh, Dongryul; Huh, Seung Jae; Nam, Heerim; Park, Won; Han, Youngyih; Lim, Do Hoon; Ahn, Yong Chan; Lee, Jeong Won; Kim, Byoung Gie; Bae, Duk Soo; Lee, Je Ho

    2008-01-01

    Purpose: To investigate the incidence, clinical characteristics, and risk factors of pelvic insufficiency fracture (PIF) after pelvic radiotherapy (RT) in cervical cancer. Methods and Materials: Medical records and imaging studies, including bone scintigraphy, CT, and MRI of 557 patients with cervical cancer who received whole-pelvic RT between January 1998 and August 2005 were reviewed. Results: Eighty-three patients were diagnosed as having PIF after pelvic RT. The 5-year cumulative incidence of PIF was 19.7%. The most commonly involved site was the sacroiliac joint. Pelvic pain developed in 48 patients (57.8%) at diagnosis. Eleven patients (13.3%) needed admission or narcotics because of severe pain, and others had good relief of symptoms with conservative management. In univariate analysis, age ≥55 years (p < 0.001), anteroposterior/posteroanterior parallel opposing technique (p = 0.001), curative treatment (p < 0.001), and radiation dose ≥50.4 Gy (p = 0.005) were the predisposing factors for development of PIF. Concurrent chemotherapy (p = 0.78) was not significant. Multivariate analysis showed that age ≥55 years (p < 0.001), body weight <55 kg (p = 0.02), curative treatment (p = 0.03), and radiation dose ≥50.4 Gy (p = 0.04) were significant predisposing factors for development of PIF. Conclusion: The development of PIF is not rare after pelvic RT. The use of multibeam arrangements to reduce the volume and dose of irradiated pelvic bone can be helpful to minimize the risk of fracture, especially in elderly women with low body weight

  18. Hyperfractionated Accelerated Radiotherapy (HART) for Anaplastic Thyroid Carcinoma: Toxicity and Survival Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Dandekar, Prasad [Head and Neck/Thyroid Unit, Royal Marsden NHS Foundation Trust, Sutton, Surrey (United Kingdom); Harmer, Clive; Barbachano, Yolanda [Department of Clinical Research and Development, Royal Marsden NHS Foundation Trust, Sutton, Surrey (United Kingdom); Rhys-Evans, Peter; Harrington, Kevin; Nutting, Christopher [Head and Neck-Thyroid Unit, Royal Marsden NHS Foundation Trust, Chelsea, London (United Kingdom); Newbold, Kate [Head and Neck/Thyroid Unit, Royal Marsden NHS Foundation Trust, Sutton, Surrey (United Kingdom); Consultant Clinical Oncologist, Royal Marsden NHS Foundation Trust, Chelsea, London (United Kingdom)

    2009-06-01

    Purpose: Anaplastic thyroid carcinoma (ATC) is one of the most aggressive cancers, and the current protocol of hyperfractionated accelerated radiotherapy was initiated to improve survival while limiting toxicities. Methods and Materials: All patients with ATC from 1991 to 2002 were accrued and received megavoltage radiotherapy from the mastoid processes to the carina up to 60 Gy in twice-daily fractions of 1.8 and 2 Gy, 6 hours apart. Results: Thirty-one patients were accrued with a median age of 69 years, and 55% were women. Debulking was performed in 26%, and total thyroidectomy, in 6%, whereas 68% received radical radiotherapy alone. Local control data were available for 27 patients: 22% had a complete response, 26% had a partial response, 15% showed progressive disease, and 37% showed static disease. Median overall survival for all 31 patients was 70 days (95% confidence interval, 40-99). There was no significant difference in median survival between patients younger (70 days) and older than 70 years (42 days), between men (70 days) and women (49days), and between patients receiving postoperative radiotherapy (77 days) and radical radiotherapy alone (35 days). Grade III or higher skin erythema was seen in 56% patients; desquamation in 21%; dysphagia in 74%; and esophagitis in 79%. Conclusion: The current protocol failed to offer a significant survival benefit, was associated with severe toxicities, and thus was discontinued. There is a suggestion that younger patients with operable disease have longer survival, but this would require a larger study to confirm it.

  19. 3-Dimentional radiotherapy versus conventional treatment plans for gastric cancer

    Directory of Open Access Journals (Sweden)

    Aghili M

    2010-11-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: The current standard of adjuvant management for gastric cancer after curative resection based on the results of intergroup 0116 is concurrent chemoradiation. Current guidelines for designing these challenging fields still include two-dimensional simulation with simple AP-PA parallel opposed design. However, the implementation of radiotherapy (RT remains a concern. Our objective was to compare three-dimensional (3D techniques to the more commonly used AP-PA technique."n"nMethods: A total of 24 patients with stages II-IV adenocarcinoma of the stomach were treated with adjuvant postoperative chemoradiation with simple AP-PA technique, using Cobalt-60. Total radiation dose was 50.4Gy. Landmark-based fields were simulated to assess PTV coverage. For each patient, three additional radiotherapy treatment plans were generated using three-dimensional (3D technique. The four treatment plans were then compared for target volume coverage and dose to normal tissues (liver, spinal cord, kidneys using dose volume histogram (DVH analysis."n"nResults: The three-dimensional planning techniques provided 10% superior PTV coverage compared to conventional AP-PA fields (p<0.001. Comparative DVHs for the right kidney, left kidney

  20. Whither radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Ross, W M

    1987-03-01

    The 1986 Glyn Evans Memorial Lecture, given at the Joint Provincial Meeting of the Royal College of Radiologists, Sheffield, September 1986, sketches an outline of the history of radiotherapy and discusses the future development of the art. Topics included are siting of centres, training needs, the relationship of radiotherapy to other medical specialities, and the advantages and disadvantages of radiotherapy practitioners forming a separate medical College. (U.K.)

  1. An analysis of anatomic landmark mobility and setup errors in radiotherapy for lung cancer

    International Nuclear Information System (INIS)

    Samson, M.J.; Soernsen de Koste, J.R. van; Boer, J.C.J. de; Tankink, J.J.; Verstraate, M.B.J.; Essers, M.; Visser, A.G.; Senan, S.

    1997-01-01

    Purpose: To identify visible structures in the thorax which exhibit little internal motion during irradiation and, to determine random and systematic setup deviations in lung cancer patients with the use of these structures. Methods: Ten patients with lung cancer were set up in the supine position, and aligned using lasers. No immobilization devices were used. With an electronic portal imaging device (Siemens Beam View PLUS ), 12 sequential images (exposure 0.54 sec.; processing time 1.5 sec.) were obtained during a single fraction of radiotherapy. These 'movie loops' were generated for the A-P fields during each of 3-5 fractions. In order to determine the mobility of internal structures during each fraction, visible structures such as the trachea, carina, the upper chest wall, aortic arch, clavicle and paraspinal line were contoured manually in each image and matched with the first image of the corresponding movie loop by means of a cross-correlation algorithm. Translations in the cranial and lateral directions and in-plane rotations were determined for each structure separately. As the reference image represents a random position, relative movements were determined by comparing the translations and rotation for every image to the calculated means per movie-loop. Standard deviations of the relative movements were determined for each structure and each patient. Patient setup was evaluated for 15 patients with lung cancer. Setup was not corrected at any time during the treatment. The electronic portal images of each fraction were matched with the digitized simulator films by using a combination of the structures which had been determined to be relatively stable in the infra-fractional analysis. Results: In the infra-fractional analysis 120 to 380 matches were made per structure (a total of 1400). The standard deviation (SD) of translations in the lateral direction was small (≤1 mm) for the trachea, thoracic wall, paraspinal line and aortic arch. This was also the

  2. Radiological incidents in radiotherapy

    International Nuclear Information System (INIS)

    Hobzova, L.; Novotny, J.

    2008-01-01

    In many countries a reporting system of radiological incidents to national regulatory body exists and providers of radiotherapy treatment are obliged to report all major and/or in some countries all incidents occurring in institution. State Office for Nuclear Safety (SONS) is providing a systematic guidance for radiotherapy departments from 1997 by requiring inclusion of radiation safety problems into Quality assurance manual, which is the basic document for obtaining a license of SONS for handling with sources of ionizing radiation. For that purpose SONS also issued the recommendation 'Introduction of QA system for important sources in radiotherapy-radiological incidents' in which the radiological incidents are defined and the basic guidance for their classification (category A, B, C, D), investigation and reporting are given. At regular periods the SONS in co-operation with radiotherapy centers is making a survey of all radiological incidents occurring in institutions and it is presenting obtained information in synoptic communication (2003 Motolske dny, 2005 Novy Jicin). This presentation is another summary report of radiological incidents that occurred in our radiotherapy institutions during last 3 years. Emphasis is given not only to survey and statistics, but also to analysis of reasons of the radiological incidents and to their detection and prevention. Analyses of incidents in radiotherapy have led to a much broader understanding of incident causation. Information about the error should be shared as early as possible during or after investigation by all radiotherapy centers. Learning from incidents, errors and near misses should be a part of improvement of the QA system in institutions. Generally, it is recommended that all radiotherapy facilities should participate in the reporting, analyzing and learning system to facilitate the dissemination of knowledge throughout the whole country to prevent errors in radiotherapy.(authors)

  3. Correlation factor analysis between radiation pneumonitis and chemo-radiotherapy in breast cancer patients

    International Nuclear Information System (INIS)

    Li Huiping; Wang Junjie; Ma Liwen; Zhang Shulan; Deng Huijing; Jia Tingzhen

    2004-01-01

    Objective: To investigate the relationship between radiotherapy-induced lung injury and chemotherapy agents as well as other factors. Methods: A total of 85 breast cancer patients received radiotherapy with sequential or concurrent chemotherapy after surgery were analysed for radiation dose, chemotherapy schedule, age, and lung disease history. Results: Five patients had clinical symptoms of radiation pneumonitis, one of them was necessary to treat and 16 patients developed radiological changes (18.8%). Close relationship was noted between incidence of radiation pneumonitis and radiation dose, timing and drugs used in chemotherapy and lung disease history. Conclusion: High irradiation dose, concurrent chemotherapy, and lung disease history can increase the rate of radiotherapy-induced pulmonary injury in breast cancer patients. (authors)

  4. SU-E-J-159: Analysis of Total Imaging Uncertainty in Respiratory-Gated Radiotherapy

    International Nuclear Information System (INIS)

    Suzuki, J; Okuda, T; Sakaino, S; Yokota, N

    2015-01-01

    Purpose: In respiratory-gated radiotherapy, the gating phase during treatment delivery needs to coincide with the corresponding phase determined during the treatment plan. However, because radiotherapy is performed based on the image obtained for the treatment plan, the time delay, motion artifact, volume effect, and resolution in the images are uncertain. Thus, imaging uncertainty is the most basic factor that affects the localization accuracy. Therefore, these uncertainties should be analyzed. This study aims to analyze the total imaging uncertainty in respiratory-gated radiotherapy. Methods: Two factors of imaging uncertainties related to respiratory-gated radiotherapy were analyzed. First, CT image was used to determine the target volume and 4D treatment planning for the Varian Realtime Position Management (RPM) system. Second, an X-ray image was acquired for image-guided radiotherapy (IGRT) for the BrainLAB ExacTrac system. These factors were measured using a respiratory gating phantom. The conditions applied during phantom operation were as follows: respiratory wave form, sine curve; respiratory cycle, 4 s; phantom target motion amplitude, 10, 20, and 29 mm (which is maximum phantom longitudinal motion). The target and cylindrical marker implanted in the phantom coverage of the CT images was measured and compared with the theoretically calculated coverage from the phantom motion. The theoretical position of the cylindrical marker implanted in the phantom was compared with that acquired from the X-ray image. The total imaging uncertainty was analyzed from these two factors. Results: In the CT image, the uncertainty between the target and cylindrical marker’s actual coverage and the coverage of CT images was 1.19 mm and 2.50mm, respectively. In the Xray image, the uncertainty was 0.39 mm. The total imaging uncertainty from the two factors was 1.62mm. Conclusion: The total imaging uncertainty in respiratory-gated radiotherapy was clinically acceptable. However

  5. SU-E-J-159: Analysis of Total Imaging Uncertainty in Respiratory-Gated Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, J; Okuda, T [Toyota memorial hospital, Toyota, Aichi (Japan); Sakaino, S; Yokota, N [Suzukake central hospital, Hamamatsu, Shizuoka (Japan)

    2015-06-15

    Purpose: In respiratory-gated radiotherapy, the gating phase during treatment delivery needs to coincide with the corresponding phase determined during the treatment plan. However, because radiotherapy is performed based on the image obtained for the treatment plan, the time delay, motion artifact, volume effect, and resolution in the images are uncertain. Thus, imaging uncertainty is the most basic factor that affects the localization accuracy. Therefore, these uncertainties should be analyzed. This study aims to analyze the total imaging uncertainty in respiratory-gated radiotherapy. Methods: Two factors of imaging uncertainties related to respiratory-gated radiotherapy were analyzed. First, CT image was used to determine the target volume and 4D treatment planning for the Varian Realtime Position Management (RPM) system. Second, an X-ray image was acquired for image-guided radiotherapy (IGRT) for the BrainLAB ExacTrac system. These factors were measured using a respiratory gating phantom. The conditions applied during phantom operation were as follows: respiratory wave form, sine curve; respiratory cycle, 4 s; phantom target motion amplitude, 10, 20, and 29 mm (which is maximum phantom longitudinal motion). The target and cylindrical marker implanted in the phantom coverage of the CT images was measured and compared with the theoretically calculated coverage from the phantom motion. The theoretical position of the cylindrical marker implanted in the phantom was compared with that acquired from the X-ray image. The total imaging uncertainty was analyzed from these two factors. Results: In the CT image, the uncertainty between the target and cylindrical marker’s actual coverage and the coverage of CT images was 1.19 mm and 2.50mm, respectively. In the Xray image, the uncertainty was 0.39 mm. The total imaging uncertainty from the two factors was 1.62mm. Conclusion: The total imaging uncertainty in respiratory-gated radiotherapy was clinically acceptable. However

  6. Radiotherapy of Painful Vertebral Hemangiomas: The Single Center Retrospective Analysis of 137 Cases

    International Nuclear Information System (INIS)

    Miszczyk, Leszek; Tukiendorf, Andrzej

    2012-01-01

    Purpose: An evaluation of dose–response relationship and an attempt to define predictive factors. Methods and Materials: A total of 137 cases of painful vertebral hemangioma irradiations (101 patients). Fraction dose (fd) varied from 2 to 15 Gy (123 fractionated and 14 radiosurgical treatments), and total dose (TD) from 8 to 30 Gy (111 cases irradiated with fd of 2 GY to TD of 24 Gy). We evaluated pain relief, changes in analgesic requirements, and reossification. Results: Means of pain relief 1, 6, 12, and 18 months after radiotherapy (defined as a decrease of primary pain level expressed in percent) were 60.5%, 65.4%, 68.3%, and 78.4%, respectively. Proportion of patients with no need for analgesics and patients using tramadol were 39%, 40%, 44%, 57%, and 20%, 17%, 22%, and 11% in these times. The proportion of patients experiencing complete/partial pain relief changed from 36/48% 1 month, to 64/22% 1.5 years after radiotherapy. No impact of radiotherapy on reossification was found. The positive impact of fd and TD increase for analgesics uptake reduction and pain relief was found. An increase of the fd by 1 Gy results in 27% chance of analgesics uptake reduction and 3.8% reduction of pain, whereas 14% analgesics uptake reduction and 2.2% of pain reduction in case of the TD. The predictive factors improving results were found: female gender, older age, better performance states (the chance of the lower analgesic treatment decreases over 2.5 times in comparison to the higher Zubrod degree), bigger Hb concentration, shorter symptoms duration and lower analgesics uptake before radiotherapy. Conclusions: The obtained data support the efficacy of radiotherapy in improving pain secondary to vertebral hemangioma, with the degree of pain amelioration being related to increasing fd and TD. The positive predictive factors were defined: female gender, older age, better performance status, increased Hb concentration, shorter symptoms duration, and lower analgesics uptake

  7. Evaluation of Thyroid Disorders During Head-and-Neck Radiotherapy by Using Functional Analysis and Ultrasonography

    International Nuclear Information System (INIS)

    Bakhshandeh, Mohsen; Hashemi, Bijan; Mahdavi, Seyed Rabie; Nikoofar, Alireza; Edraki, Hamid Reza; Kazemnejad, Anoshirvan

    2012-01-01

    Purpose: To evaluate thyroid function and vascular changes during radiotherapy for patients with head and neck cancer. Methods and Materials: Fifty patients treated with primary or postoperative radiotherapy for various cancers in the head and neck region were prospectively evaluated. The serum samples (triiodothyronine [T3], thyroxine [T4], thyroid-stimulating hormone [TSH], free triiodothyronine [FT3], and free thyroxine [FT4]), the echo level of the thyroid gland, and color Doppler ultrasonography (CDU) parameters of the right inferior thyroid artery (RITA) of the patients were measured before and at regular intervals during radiotherapy. The thyroid gland dose-volume histograms of the patients were derived from their computed tomography-based treatment plans. Results: There was a significant fall in TSH level (p 2 ). There were significant rises in the patients’ pulsatility index, resistive index, peak systolic velocity, blood volume flow levels, and RITA diameter (p < 0.0001), as detected by CDU during radiotherapy, compared to those parameters measured before the treatment. Hypoechogenicity and irregular echo patterns (p < 0.0001) were seen during radiotherapy compared to those before treatment. There was significant Pearson’s correlation between the CDU parameters and T4, FT4, and TSH levels. Conclusions: Radiation-induced thyroiditis is regarded as primary damage to the thyroid gland. Thyroiditis can subsequently result in hypothyroidism or hyperthyroidism. Our results demonstrated that changes in thyroid vessels occur during radiotherapy delivered to patients. Vessel changes also can be attributed to the late effect of radiation on the thyroid gland. The hypoechogenicity and irregular echo patterns observed in patients may result from the increase in intrathyroidal flow.

  8. Treatment outcome and risk analysis for cataract after radiotherapy of localized ocular adnexal mucosa-associated lymphoid tissue (MALT) lymphoma

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    Park, Hee Hyun; Lee, Sea Won; Sung, Soo Yoon; Choi, Byung Oak [Dept. of Radiation Oncology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul, (Korea, Republic of)

    2017-09-15

    We retrospectively reviewed the results of radiotherapy for localized ocular adnexal MALT lymphoma (OAML) to investigate the risk factors of cataract. Sixty-seven patients with stage IE OAML treated with radiotherapy at Seoul St. Mary’s Hospital from 2001 to 2016 were included. Median treatment dose was 30 Gy. Lens protection was done in 52 (76%) patients. Radiation therapy (RT) extent was as follows: superficial (82.1%), tumor mass (4.5%), and entire orbital socket (13.4%). The risk factors for symptomatic cataract were analyzed using the Cox proportional hazard model. Median follow-up time was 50.9 months (range, 1.9 to 149.4 months). All patients were alive at the time of analysis. There were 7 recurrences and there was no local recurrence. Median time to recurrence was 40.4 months. There were 14 cases of symptomatic cataract. Dose >30 Gy had hazard ratio of 3.47 for cataract (p = 0.026). Omitting lens protection showed hazard ratio of 4.10 (p = 0.008). RT achieves excellent local control of ocular MALT lymphoma. Consideration of RT-related factors such as lens protection and radiation dose at the stage of RT planning may reduce the risk of RT-induced cataract after radiotherapy.

  9. Radiotherapy for the prophylaxis of heterotopic ossification: A systematic review and meta-analysis of published data

    International Nuclear Information System (INIS)

    Popovic, Marko; Agarwal, Arnav; Zhang, Liying; Yip, Cheryl; Kreder, Hans J.; Nousiainen, Markku T.; Jenkinson, Richard; Tsao, May; Lam, Henry; Milakovic, Milica; Wong, Erin; Chow, Edward

    2014-01-01

    Introduction: Following surgery, the formation of heterotopic ossification (HTO) can limit mobility and impair quality of life. Radiotherapy has been proven to provide efficacious prophylaxis against HTO, especially in high-risk settings. Purpose: The current review aims to determine the factors influencing HTO formation in patients receiving prophylactic radiotherapy. Methods: A systematic search of the literature was conducted on Ovid Medline, Embase and the Cochrane Central Register of Controlled Trials. Studies were included if they reported the percentage of sites developing heterotopic ossification after receiving a specified dose of prophylactic radiotherapy. Weighted linear regression analysis was conducted for continuous or categorical predictors. Results: Extracted from 61 articles, a total of 5464 treatment sites were included, spanning 85 separate study arms. Most sites were from the hip (97.7%), from United States patients (55.2%), and had radiation prescribed postoperatively (61.6%) at a dose of 700 cGy (61.0%). After adjusting for radiation site, there was no statistically significant relationship between the percentage of sites developing HTO and radiation dose (p = 0.1) or whether radiation was administered preoperatively or postoperatively (p = 0.1). Sites with previous HTO formation were more likely to develop recurrent HTO than those without previous HTO formation (p = 0.04). There was a statistically significant negative relationship between the HTO development and the cohort mean year of treatment (p = 0.007). Conclusion: Decreases in rates of HTO over time in this patient population may be a function of more efficacious surgical regimens and prophylactic radiotherapy

  10. Analysis of Electronic Densities and Integrated Doses in Multiform Glioblastomas Stereotactic Radiotherapy

    International Nuclear Information System (INIS)

    Baron-Aznar, C.; Moreno-Jimenez, S.; Celis, M. A.; Ballesteros-Zebadua, P.; Larraga-Gutierrez, J. M.

    2008-01-01

    Integrated dose is the total energy delivered in a radiotherapy target. This physical parameter could be a predictor for complications such as brain edema and radionecrosis after stereotactic radiotherapy treatments for brain tumors. Integrated Dose depends on the tissue density and volume. Using CT patients images from the National Institute of Neurology and Neurosurgery and BrainScan(c) software, this work presents the mean density of 21 multiform glioblastomas, comparative results for normal tissue and estimated integrated dose for each case. The relationship between integrated dose and the probability of complications is discussed

  11. Analysis of quality control protocol implementation of equipment in radiotherapy services

    International Nuclear Information System (INIS)

    Calcina, Carmen S. Guzman; Lima, Luciana P. de; Rubo, Rodrigo A.; Ferraz, Eduardo; Almeida, Adelaide de

    2000-01-01

    Considering the importance of the Quality Assurance in the radiotherapy services, there was an interest to make tests' evaluation for a Quality Control for the cobalt equipment, linear accelerator and simulator as a classification and comparison. The work proposed is a suggestion that can serve as tool for medical physicists that are starting to work in the radiotherapy area and for the most experts. The discussions were made by the gathering of local tests and official protocols, resulting in a minimum protocol as a suggestion for a routine work, emphasizing the periodicity and level of tolerance of each one of the tests. (author)

  12. Management of extramedullary plasmacytoma: Role of radiotherapy and prognostic factor analysis in 55 patients.

    Science.gov (United States)

    Wen, Ge; Wang, Weihu; Zhang, Yujing; Niu, Shaoqing; Li, Qiwen; Li, Yexiong

    2017-10-01

    To investigate potential prognostic factors affecting patient outcomes and to evaluate the optimal methods and effects of radiotherapy (RT) in the management of extramedullary plasmacytoma (EMP). Data from 55 patients with EMP between November 1999 and August 2015 were collected. The median age was 51 (range, 22-77) years. The median tumor size was 3.5 (range, 1.0-15.0) cm. The median applied dose was 50.0 (range, 30.0-70.0) Gy. Thirty-nine patients (70.9%) presented with disease in the head or neck region. Twelve patients received RT alone, 9 received surgery (S) alone, 3 received chemotherapy (CT) alone, and 3 patients did not receive any treatment. Combination therapies were applied in 28 patients. The median follow-up duration was 56 months. The 5-year local recurrence-free survival (LRFS), multiple myeloma-free survival (MMFS), progression-free survival (PFS) and overall survival (OS) rates were 79.8%, 78.6%, 65.2% and 76.0%, respectively. Univariate analysis revealed that RT was a favourable factor for all examined endpoints. Furthermore, head and neck EMPs were associated with superior LRFS, MMFS and PFS. Tumor size <4 cm was associated with superior MMFS, PFS and OS; serum M protein negativity was associated with superior MMFS and PFS; age ≥50 years and local recurrence were associated with poor MMFS. The dose ≥45 Gy group exhibited superior 5-year LRFS, MMFS and PFS rates (94.7%, 94.4%, 90.0%, respectively), while the corresponding values for the dose <45 Gy group were 62.5% (P=0.008), 53.3% (P=0.036) and 41.7% (P<0.001). Involved-site RT of at least 45 Gy should be considered for EMP. Furthermore, patients with head and neck EMP, tumor size <4 cm, age <50 years and serum M protein negativity had better outcomes.

  13. Results of salvage radiotherapy after inadequate surgery in invasive cervical carcinoma patients: A retrospective analysis

    International Nuclear Information System (INIS)

    Saibishkumar, Elantholi P.; Patel, Firuza D.; Ghoshal, Sushmita; Kumar, Vinay; Karunanidhi, Gunaseelan; Sharma, Suresh C.

    2005-01-01

    Purpose: To evaluate the results of salvage radiotherapy (RT) after inadequate surgery in patients with invasive carcinoma of the cervix. Methods and Materials: Between 1996 and 2001, 105 invasive cervical carcinoma patients were treated at our center with external beam RT with or without intracavitary RT after having undergone total/subtotal hysterectomy at outside institutions. Results: The median follow-up was 34 months. The gap between surgery and RT was 23-198 days (median, 80). Clinically visible residual disease was present in 81 patients (77.1%). Total hysterectomy had been done in 82 patients (78%) and subtotal hysterectomy in 23 patients (22%). The 5-year overall survival, disease-free survival, and pelvic control rates of all patients were 55.2%, 53.3%, and 72.4%, respectively. On univariate analysis, older age, total hysterectomy, hemoglobin level >10 g% before RT, nonsquamous histologic type, use of intracavitary RT, a shorter gap between surgery and RT, and the absence of, or a small volume of, residual disease favorably affected the outcome. The 5-year actuarial rate of late toxicity (Radiation Therapy Oncology Group Criteria) was 19% in the rectum, 4.8% in the bladder, 24.8% in the skin, and 14.3% in the small intestine. Conclusions: Inadequate and inappropriate surgery in invasive cervical cancer with resulting gross residual disease is common in India. Factors such as the use of intracavitary RT, the correction of anemia, and a shorter gap between surgery and RT will enable postoperative RT to achieve acceptable results with minimal morbidity

  14. Clinical analysis of radiotherapy for nasopharyngeal carcinoma in 145 children and adolescents

    International Nuclear Information System (INIS)

    Liu Juying; Wei Baoqing; Lu Jincheng; Zhu Jun; Zhang Yiqin

    2003-01-01

    Objective: To evaluate the clinical characteristics, treatment, outcome and complications of child and adolescent nasopharyngeal carcinoma (NPC). Methods: From January 1970 to April 1997, the records of 145 NPC patients younger than 21 years of age were reviewed. The clinical stages according to 92' Chinese NPC Staging System were: stage I in 1, II in 8, III in 79 and IV in 57. All patients were treated with external beam radiotherapy. Before 1988, parallel opposed lateral pre-auricular portals were chiefly used in 75 patients and after 1988, parallel opposed lateral facio-cervical portals were adopted in 70. The radiation dose to the primary tumor ranged 45-80 Gy: 70 Gy in 50 cases and 32 of them also received chemotherapy. Results: Distant metastasis developed in 26 cases, while local and/or regional recurrence in 14. The actuarial overall survival rates of 1-, 3-, 5 , and 10-years were 96.3%, 79.9%, 76.5% and 69.4%, respectively. Among 45 dead cases, 16 did so of metastasis, 11 of local and/or regional recurrence and 18 of other reasons. Univariate analysis suggested that clinical stage, size and site of involved lymph nodes, skull base involvement were significant prognostic factors of survival, whereas sex, age,dose, therapeutic method and chemotherapy were not. Conclusions: 1. Even though the majority of pediatric and adolescent NPC were advanced , it signifies a relatively good survival. 2. As the normal tissue of pediatric and adolescent patients tolerates radiation poorly, prudence should be meticulously practiced in deciding the radiation dose and radiotherapeutic fields

  15. Finding dose-volume constraints to reduce late rectal toxicity following 3D-conformal radiotherapy (3D-CRT) of prostate cancer

    International Nuclear Information System (INIS)

    Greco, Carlo; Mazzetta, Chiara; Cattani, Federica; Tosi, Giampiero; Castiglioni, Simona; Fodor, Andrei; Orecchia, Roberto

    2003-01-01

    Background and purpose: The rectum is known to display a dose-volume effect following high-dose 3D-conformal radiotherapy (3D-CRT). The aim of the study is to search for significant dose-volume combinations with the specific treatment technique and patient set-up currently used in our institution. Patients and methods: We retrospectively analyzed the dose-volume histograms (DVH) of 135 patients with stage T1b-T3b prostate cancer treated consecutively with 3D-CRT between 1996 and 2000 to a total dose of 76 Gy. The median follow-up was 28 months (range 12-62). All late rectal complications were scored using RTOG criteria. Time to late toxicity was assessed using the Kaplan-Meyer method. The association between variables at baseline and ≥2 rectal toxicity was tested using χ 2 test or Fisher's exact test. A multivariate analysis using logistic regression was performed. Results: Late rectal toxicity grade ≥2 was observed in 24 of the 135 patients (17.8%). A 'grey area' of increased risk has been identified. Average DVHs of the bleeding and non-bleeding patients were generated. The area under the percent volume DVH for the rectum of the bleeding patients was significantly higher than that of patients without late rectal toxicity. On multivariate analysis the correlation between the high risk DVHs and late rectal bleeding was confirmed. Conclusions: The present analysis confirms the role of the rectal DVH as a tool to discriminate patients undergoing high-dose 3D-CRT into a low and a high risk of developing late rectal bleeding. Based on our own results and taking into account the data published in the literature, we have been able to establish new dose-volume constraints for treatment planning: if possible, the percentage of rectal volume exposed to 40, 50, 60, 72 and 76 Gy should be limited to 60, 50, 25, 15 and 5%, respectively

  16. Analysis of RDC n. 20/2006 da Anvisa/MS practices: point of view of the residents in medical physics of radiotherapy

    International Nuclear Information System (INIS)

    Timm, Noe R.; Pianoschi, Thatiane; Alva-Sanhez, Mirko S.

    2016-01-01

    Operations of the radiotherapy services in Brazil are overseen by the National Health Surveillance Agency (Anvisa), which due to the complexity and concern about the use of ionizing radiation in health, coordinated the development of the technical regulation RDC number 20 for the operation of radiotherapy. The regulation aims to protect the health of patients, professionals involved and the general public. The objective of this study was to analyze practices, especially in the aspects of responsibilities of Physicists, to facilitate adjustment of radiotherapy services to the regulation described in Technical RDC number 20/2006 Anvisa. Thus, the analysis can be used as an alignment tool among professional organ monitoring and Physical radiotherapy. (author)

  17. Dosimetric implications of changes in patient repositioning and organ motion in conformal radiotherapy for prostate cancer

    International Nuclear Information System (INIS)

    Miralbell, Raymond; Oezsoy, Orhan; Pugliesi, Angela; Carballo, Natalia; Arnalte, Raquel; Escude, Lluis; Jargy, Clara; Nouet, Philippe; Rouzaud, Michel

    2003-01-01

    Purpose: To assess the influence of patient repositioning and organ motion on dose distribution within the prostate and the seminal vesicles (clinical target volume, (CTV)). Material and methods: Nine patients were simulated and treated in the supine position, with an empty bladder, and without immobilization devices. While on treatment, patients underwent weekly pelvic computed tomography (CT) scans under conditions identical to those at simulation. Patients were aligned using lasers on anterior and lateral skin tattoos, onto which lead markers were placed. After each CT scan (n=53) the CTV was redefined by contouring, and a new isocenter was obtained. A six-field technique was used. The field margins around the CTV were 20 mm in the cranio-caudal axis, and 13 mm in the other axes, except in the lateral fields where a 10 mm posterior margin was used. Dose-volume histograms (DVHs) for each organ were compared with those determined at simulation, using the notion of the proportional change in the area under the CTV-DVH curve resulting from a change in treatment plan (cDVH). Results: The reproducibility of the dose distribution was good for the prostate (%cDVH, mean±SD: -0.97±2.11%) and less than optimal for the seminal vesicles (%cDVH, mean±SD: -4.66±10.45%). When correlating prostate %cDVH variations with displacements of the isocenter in the Y axis (antero-posterior) the %cDVH exceeded (-)5% in only two dosimetries, both with an isocenter shift of >10 mm. For the seminal vesicles, however, ten out of 53 dosimetries showed a %cDVH exceeding (-) 5%. In nine of these ten dose distribution studies the posterior shift of the isocenter exceeded 8 mm. Conclusions: Precise targeting of prostate radiotherapy is primarily dependent on careful daily set-up and on random changes in rectal geometry. Margins no less than 10 mm around the prostate and at least 15 mm around the seminal vesicles are probably necessary to insure adequate target coverage with a six

  18. The expression of epidermal growth factor receptor results in a worse prognosis for patients with rectal cancer treated with preoperative radiotherapy: a multicenter, retrospective analysis

    International Nuclear Information System (INIS)

    Giralt, Jordi; Heras, Manuel de las; Cerezo, Laura; Eraso, Aranzazu; Hermosilla, Edurado; Velez, Dolores; Lujan, Juan; Espin, Eloi; Rossello, Jose; Majo, Joaquin; Benavente, Sergi; Armengol, Manel; Torres, I. de

    2005-01-01

    Background and purpose: Expression of epidermal growth factor receptor (EGFR) is observed in 50-70% of colorectal carcinoma and is associated with poor prognosis. The aim of this study was to determine the prognostic value of EGFR status before radiotherapy in a group of patients with locally advanced rectal cancer treated with preoperative radiotherapy. Patients and methods: Eighty-seven patients were studied retrospectively. Treatment consisted of pelvic radiotherapy, in 50 patients with concomitant chemotherapy and surgical resection. Immunohistochemistry for EGFR was determined at the preradiation biopsy and in the resected specimens. Immunohistochemical analysis for EGFR expression was evaluated according to extension and staining intensity. We defined positive staining (EGFR positive), when extension was 5% or more. Results: A total of 52 of 87 tumors showed EGFR positive status at biopsy (60%) and EGFR expression was associated neither with clinical tumor stage nor with clinical nodal stage. EGFR positive expression was linked to a lack of pathologic complete response to preoperative radiotherapy (P=0.006). Disease-free survival was lower among patients with EGFR positive status before radiotherapy (P=0.003). In a multivariate analysis EGFR expression at biopsy was a statistically significant predictor of disease-free survival, RR=2.88 (1.1-7.8), P=0.036. Conclusions: EGFR is expressed in a significant number of rectal tumors. EGFR-positive expression before radiotherapy is an indicator for poor response and low disease-free survival

  19. Analysis of Magnetic Resonance Image Signal Fluctuations Acquired During MR-Guided Radiotherapy.

    Science.gov (United States)

    Breto, Adrian L; Padgett, Kyle R; Ford, John C; Kwon, Deukwoo; Chang, Channing; Fuss, Martin; Stoyanova, Radka; Mellon, Eric A

    2018-03-28

    Magnetic resonance-guided radiotherapy (MRgRT) is a new and evolving treatment modality that allows unprecedented visualization of the tumor and surrounding anatomy. MRgRT includes daily 3D magnetic resonance imaging (MRI) for setup and rapidly repeated near real-time MRI scans during treatment for target tracking. One of the more exciting potential benefits of MRgRT is the ability to analyze serial MRIs to monitor treatment response or predict outcomes. A typical radiation treatment (RT) over the span of 10-15 minutes on the MRIdian system (ViewRay, Cleveland, OH) yields thousands of "cine" images, each acquired in 250 ms. This unique data allows for a glimpse in image intensity changes during RT delivery. In this report, we analyze cine images from a single fraction RT of a glioblastoma patient on the ViewRay platform in order to characterize the dynamic signal changes occurring during RT therapy. The individual frames in the cines were saved into DICOM format and read into an MIM image analysis platform (MIM Software, Cleveland, OH) as a time series. The three possible states of the three Cobalt-60 radiation sources-OFF, READY, and ON-were also recorded. An in-house Java plugin for MIM was created in order to perform principal component analysis (PCA) on each of the datasets. The analysis resulted in first PC, related to monotonous signal increase over the course of the treatment fraction. We found several distortion patterns in the data that we postulate result from the perturbation of the magnetic field due to the moving metal parts in the platform while treatment was being administered. The largest variations were detected when all Cobalt-60 sources were OFF. During this phase of the treatment, the gantry and multi-leaf collimators (MLCs) are moving. Conversely, when all Cobalt-60 sources were in the ON position, the image signal fluctuations were minimal, relating to very little mechanical motion. At this phase, the gantry, the MLCs, and sources are fixed

  20. Main stages in the development of radiation immunology: from immunochemical analysis of injury to monitored radiotherapy

    International Nuclear Information System (INIS)

    Yarilin, A.A.; Kashkin, K.P.

    1982-01-01

    The results of research of the radiation action on immunity are presented. The results of immunochemical investigation of radiation tissue injuries are considered. Much attention is given to the problem of radiation injury and repair of the lymphoid system. It is shown that the next stage of development of radiation immunology is immunologic control of radiotherapy of oncologic patients

  1. Radiation therapy and internet - what can patients expect? homepage analysis of german radiotherapy institutions.

    Science.gov (United States)

    Janssen, Stefan; Meyer, Andreas; Vordermark, Dirk; Steinmann, Diana

    2010-12-01

    the internet as a source of medical information has emerged during the last years. There is a confusing amount of medical websites with a great diversity of quality. Websites of radiotherapy institutions could offer a safe and an easy-to-control way to assist patients' requests. 205 internet appearances of German radiotherapy institutions were analyzed in June 2009 (nonuniversity hospitals n = 108, medical practices n = 62, university hospitals n = 35). For the evaluation of each homepage verifiable criteria concerning basic information, service and medical issues were used. the quality of information published via internet by different radiotherapy institutions showed a large variety. Basic information like telephone numbers, operating hours, and direction guidance were provided in 96.7%, 40%, and 50.7%, respectively. 85% of the websites introduced the staff, 50.2% supplied photos and 14% further information on the attending physicians. The mean amount of continuative links to other websites was 5.4, the mean amount of articles supplying medical information for patients summed up to 4.6. Medical practices and university hospitals had statistically significant more informative articles and links to other websites than nonuniversity hospitals. No statistically significant differences could be found in most other categories like service issues and basic information. internet presences of radiotherapy institutions hold the chance to supply patients with professional and individualized medical information. While some websites are already using this opportunity, others show a lack of basic information or of user-friendliness.

  2. Progress of radiotherapy by three-dimensional treatment planning

    International Nuclear Information System (INIS)

    Imada, Hajime; Nomoto, Satoshi; Takahashi, Hiroyuki; Nakata, Hajime

    1998-01-01

    The recent progress of three-dimensional radiation treatment planning was reviewed. And clinical cases such as lung cancer and breast cancer are introduced. In the University of Occupational and Development Health, the treatment system FOCUS which is made up of CT simulator and linac was used mainly. Three-dimensional treatment planning was carried for about 90% of 330 patients who underwent radiotherapy for one year. The target becomes to be accurate and dose distribution with all CT slices in radiation field can be confirmed by using three-dimensional radiation treatment planning apparatus. High dose irradiation localized to tumor part is possible. Relations between total dose and volume of normal tissue and/or tumor can be estimated numerically and easily by DVH. A prediction of indication and affection became possible by this procedure. In conclusion, generalization of three-dimensional radiation treatment planning will bring progress of more effective radiotherapy with less adverse reaction. (K.H.). 21 refs

  3. Impact of thoracic radiotherapy timing in limited-stage small-cell lung cancer: usefulness of the individual patient data meta-analysis.

    Science.gov (United States)

    De Ruysscher, D; Lueza, B; Le Péchoux, C; Johnson, D H; O'Brien, M; Murray, N; Spiro, S; Wang, X; Takada, M; Lebeau, B; Blackstock, W; Skarlos, D; Baas, P; Choy, H; Price, A; Seymour, L; Arriagada, R; Pignon, J-P

    2016-10-01

    Chemotherapy (CT) combined with radiotherapy is the standard treatment of 'limited-stage' small-cell lung cancer. However, controversy persists over the optimal timing of thoracic radiotherapy and CT. We carried out a meta-analysis of individual patient data in randomized trials comparing earlier versus later radiotherapy, or shorter versus longer radiotherapy duration, as defined in each trial. We combined the results from trials using the stratified log-rank test to calculate pooled hazard ratios (HRs). The primary outcome was overall survival. Twelve trials with 2668 patients were eligible. Data from nine trials comprising 2305 patients were available for analysis. The median follow-up was 10 years. When all trials were analysed together, 'earlier or shorter' versus 'later or longer' thoracic radiotherapy did not affect overall survival. However, the HR for overall survival was significantly in favour of 'earlier or shorter' radiotherapy among trials with a similar proportion of patients who were compliant with CT (defined as having received 100% or more of the planned CT cycles) in both arms (HR 0.79, 95% CI 0.69-0.91), and in favour of 'later or longer' radiotherapy among trials with different rates of CT compliance (HR 1.19, 1.05-1.34, interaction test, P < 0.0001). The absolute gain between 'earlier or shorter' versus 'later or longer' thoracic radiotherapy in 5-year overall survival for similar and for different CT compliance trials was 7.7% (95% CI 2.6-12.8%) and -2.2% (-5.8% to 1.4%), respectively. However, 'earlier or shorter' thoracic radiotherapy was associated with a higher incidence of severe acute oesophagitis than 'later or longer' radiotherapy. 'Earlier or shorter' delivery of thoracic radiotherapy with planned CT significantly improves 5-year overall survival at the expense of more acute toxicity, especially oesophagitis. © The Author 2016. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights

  4. Stereotactic body radiotherapy for centrally located stage I NSCLC. A multicenter analysis

    Energy Technology Data Exchange (ETDEWEB)

    Schanne, Daniel H.; Nestle, Ursula; Grosu, Anca L. [Universitaetsklinik Freiburg, Klinik fuer Strahlenheilkunde, Freiburg (Germany); Allgaeuer, Michael [Barmherzige Brueder, Klinik fuer Strahlentherapie, Regensburg (Germany); Andratschke, Nicolaus; Molls, Michael [TU Muenchen, Klinik und Poliklinik fuer Strahlentherapie und Radiologische Onkologie, Muenchen (Germany); Appold, Steffen [Universitaetsklinikum Dresden, Klinik und Poliklinik fuer Strahlentherapie und Radioonkologie, Dresden (Germany); Dieckmann, Ute [Allgemeines Krankenhaus Wien, Univ. Klinik fuer Strahlentherapie, Wien (Austria); Ernst, Iris [Universitaetsklinikum Muenster, Klinik fuer Strahlentherapie, Muenster (Germany); Ganswindt, Ute [LMU Muenchen, Klinik und Poliklinik fuer Strahlentherapie und Radioonkologie, Muenchen (Germany); Holy, Richard [Universitaetsklinikum Aachen, Klinik fuer Strahlentherapie, Aachen (Germany); Nevinny-Stickel, Meinhard [Medizinischen Universitaet Innsbruck, Univ. Klinik fuer Strahlentherapie und Radioonkologie, Innsbruck (Austria); Semrau, Sabine [Universitaetsklinikum Erlangen, Strahlenklinik Erlangen, Erlangen (Germany); Sterzing, Florian [Universitaetsklinikum Heidelberg, Klinik fuer Radioonkologie und Strahlentherapie, Heidelberg (Germany); Wittig, Andrea [Philipps-Universitaet Marburg, Klinik fuer Strahlentherapie und Radioonkologie, Marburg (Germany); Guckenberger, Matthias [Universitaet Wuerzburg, Klinik und Poliklinik fuer Strahlentherapie, Wuerzburg (Germany)

    2014-08-27

    The purpose of this work is to analyze patterns of care and outcome after stereotactic body radiotherapy (SBRT) for centrally located, early-stage, non-small cell lung cancer (NSCLC) and to address the question of potential risk for increased toxicity in this entity. A total of 90 patients with centrally located NSCLC were identified among 613 cases in a database of 13 German and Austrian academic radiotherapy centers. The outcome of centrally located NSCLC was compared to that of cases with peripheral tumor location from the same database. Patients with central tumors most commonly presented with UICC stage IB (50 %), while the majority of peripheral lesions were stage IA (56 %). Average tumor diameters were 3.3 cm (central) and 2.8 cm (peripheral). Staging PET/CT was available for 73 and 74 % of peripheral and central tumors, respectively. Biopsy was performed in 84 % (peripheral) and 88 % (central) of cases. Doses varied significantly between central and peripheral lesions with a median BED{sub 10} of 72 Gy and 84 Gy, respectively (p < 0.001). Fractionation differed as well with medians of 5 (central) and 3 (peripheral) fractions (p < 0.001). In the Kaplan-Meier analysis, 3-year actuarial overall survival was 29 % (central) and 51 % (peripheral; p = 0.004) and freedom from local progression was 52 % (central) and 84 % (peripheral; p < 0.001). Toxicity after treatment of central tumors was low with no grade III/IV and one grade V event. Mortality rates were 0 and 1 % after 30 and 60 days, respectively. Local tumor control in patients treated with SBRT for centrally located, early-stage NSCLC was favorable, provided ablative radiation doses were prescribed. This was, however, not the case in the majority of patients, possibly due to concerns about treatment-related toxicity. Reported toxicity was low, but prospective trials are needed to resolve the existing uncertainties and to establish safe high-dose regimens for this cohort of patients. (orig.) [German] Ziel

  5. Mild soaps and radiotherapy: a survey of the UK public to identify brands of soap considered mild and analysis of these to ascertain suitability for recommendation in radiotherapy departments.

    Science.gov (United States)

    Robertson, K; Brown, P

    2011-05-01

    Cancer agencies recommend that patients use mild soap when undergoing external beam radiotherapy to minimise skin reactions. They define 'mild soap' as non-alkaline, lanolin free, unperfumed soap with a neutral pH. This study aimed to identify which soaps the UK public perceive as mild and ascertain if these were clinically mild and could potentially be recommended within radiotherapy departments. A survey of 237 participants identified eight top brands of mild soap, which were then tested for pH and analysed for potential irritants. All soaps were lanolin free and non-alkaline, with Simple and Johnson's the closest to pH 5.5. All contained fragrances except Simple and E45. Dove, Pears and Imperial Leather contained the highest concentration of fragrances. All soaps except E45 contained potential irritants. Only Simple and E45 fit the cancer agencies' definition of mild soap and could therefore be recommended for radiotherapy patients. Future research should identify current practices and recommendations in the UK as anecdotal evidence suggests large variations in skin care advice. Further scientific analysis could potentially identify cheaper brands that fit the definition of 'mild'. UK recommendations should be standardised and consistent with best practice to reduce skin reaction severity in radiotherapy patients. © 2010 Blackwell Publishing Ltd.

  6. Evaluation of compensation in breast radiotherapy: a planning study using multiple static fields

    International Nuclear Information System (INIS)

    Donovan, Ellen M.; Johnson, Ursula; Shentall, Glyn; Evans, Philip M.; Neal, Anthony J.; Yarnold, John R.

    2000-01-01

    Purpose: A method that uses electronic portal imaging to design intensity-modulated beams for compensation in breast radiotherapy was implemented using multiple static fields in a planning study. We present the results of the study to verify the algorithm, and to assess improvements to the dosimetry. Methods and Materials: Fourteen patients were imaged with computed tomography (CT) and on a treatment unit using an electronic portal imager. The portal imaging data were used to design intensity-modulated beams to give an ideal dose distribution in the breast. These beams were implemented as multiple static fields added to standard wedged tangential fields. Planning of these treatments was performed on a commercial treatment planning system (Target 2, IGE Medical Systems, Slough, U.K.) using the CT data for each patient. Dose-volume histogram (DVH) analysis of the plans with and without multileaf collimator (MLC) compensation was carried out. This work has been used as the basis for a randomized clinical trial investigating whether improvements in dosimetry are correlated with the reduction of long-term side effects from breast radiotherapy. Results: The planning analysis showed a mean increase in target volume receiving 95-105% of prescribed dose of 7.5% (range -0.8% to 15.9%) when additional MLC compensation was applied. There was no change to the minimum dose for all 14 patient data sets. The change in the volume of breast tissue receiving over 105% of prescribed dose, when applying MLC compensation, was between -1.4% and 11.9%, with positive numbers indicating an improvement. These effects showed a correlation with breast size; the larger the breast the greater the amount of improvement. Conclusions: The method for designing compensation for breast treatments using an electronic portal imager has been verified using planning on CT data for 14 patients. An improvement was seen in planning when applying MLC compensation and this effect was greater the larger the

  7. SU-E-T-469: Implementation of VAs Web-Based Radiotherapy Incident Reporting and Analysis System (RIRAS)

    International Nuclear Information System (INIS)

    Kapoor, R; Palta, J; Hagan, M; Malik, G

    2015-01-01

    Purpose: This Web-based Radiotherapy Incident Reporting and Analysis System (RIRAS) is a tool to improve quality of care for radiation therapy patients. This system is an important facet of continuing effort by our community to maintain and improve safety of radiotherapy.Material and Methods: VA’s National Radiation Oncology Program office has embarked on a program to electronically collect adverse events and good-catch data of radiation treatment of over 25,000 veterans treated with radiotherapy annually. This VA-Intranet based software design has made use of dataset taxonomies and data dictionaries defined in AAPM/ASTRO reports on error reporting. We used proven industrial and medical event reporting techniques to avoid several common problems faced in effective data collection such as incomplete data due to data entry fatigue by the reporters, missing data due to data difficult to obtain or not familiar to most reporters, missing reports due to fear of reprisal etc. This system encompasses the entire feedback loop of reporting an incident, analyzing it for salient details, and developing interventions to prevent it from happening again. The analysis reports with corrective, learning actions are shared with the reporter/facility and made public to the community (after deidentification) as part of the learning process. Results: Till date 50 incident/good catches have been reported in RIRAS and we have completed analysis on 100% of these reports. This is done due to the fact that each reported incidents is investigated and a complete analysis/patient-safety-work-product report is generated by radiation oncology domain-experts. Conclusions Because of the completeness of the data, the system has enabled us to analyze process steps and track trends of major errors which in the future will lead to implementing system wide process improvement steps and safe standard operating procedures for each radiotherapy treatment modality/technique and fulfills our goal of

  8. SU-E-T-469: Implementation of VAs Web-Based Radiotherapy Incident Reporting and Analysis System (RIRAS)

    Energy Technology Data Exchange (ETDEWEB)

    Kapoor, R; Palta, J; Hagan, M [Veteran Health Administration, Richmond, Virginia (United States); Virginia Commonwealth University, Richmond, VA (United States); Malik, G [TSG Innovations Inc. (United States)

    2015-06-15

    Purpose: This Web-based Radiotherapy Incident Reporting and Analysis System (RIRAS) is a tool to improve quality of care for radiation therapy patients. This system is an important facet of continuing effort by our community to maintain and improve safety of radiotherapy.Material and Methods: VA’s National Radiation Oncology Program office has embarked on a program to electronically collect adverse events and good-catch data of radiation treatment of over 25,000 veterans treated with radiotherapy annually. This VA-Intranet based software design has made use of dataset taxonomies and data dictionaries defined in AAPM/ASTRO reports on error reporting. We used proven industrial and medical event reporting techniques to avoid several common problems faced in effective data collection such as incomplete data due to data entry fatigue by the reporters, missing data due to data difficult to obtain or not familiar to most reporters, missing reports due to fear of reprisal etc. This system encompasses the entire feedback loop of reporting an incident, analyzing it for salient details, and developing interventions to prevent it from happening again. The analysis reports with corrective, learning actions are shared with the reporter/facility and made public to the community (after deidentification) as part of the learning process. Results: Till date 50 incident/good catches have been reported in RIRAS and we have completed analysis on 100% of these reports. This is done due to the fact that each reported incidents is investigated and a complete analysis/patient-safety-work-product report is generated by radiation oncology domain-experts. Conclusions Because of the completeness of the data, the system has enabled us to analyze process steps and track trends of major errors which in the future will lead to implementing system wide process improvement steps and safe standard operating procedures for each radiotherapy treatment modality/technique and fulfills our goal of

  9. Economic consequence of local control with radiotherapy: Cost analysis of internal mammary and medial supraclavicular lymph node radiotherapy in breast cancer

    International Nuclear Information System (INIS)

    Lievens, Yolande; Kesteloot, Katrien; Bogaert, Walter van den

    2005-01-01

    Purpose: To investigate the financial implications of radiotherapy (RT) to the internal mammary and medial supraclavicular lymph node chain (IM-MS) in postoperative breast cancer. Methods and Materials: A cost-effectiveness and cost-utility analysis were performed, using Markov models, comparing the early and delayed costs and effects of IM-MS during a 20-year time span from a societal viewpoint. The outcome estimates were based on Level I evidence from postoperative RT literature and the cost estimates on the standard practice of the Leuven University Hospitals, with the RT costs derived from an activity-based costing program developed in the department. Results: On the basis of the assumptions of the model and seen during a 20-year time span, primary treatment including IM-MS RT results in a cost savings (approximately EURO 10,000) compared with a strategy without RT. Because IM-MS RT also results in better clinical effectiveness and greater quality of life, the treatment with IM-MS dominates the approach without IM-MS. Sensitivity analyses confirmed the robustness of these results in all tested circumstances. Although threshold values were found for the cost of IM-MS, the cost at relapse, and the quality of life after treatment, these were substantially different from the baseline estimates, indicating that it is very unlikely that omitting IM-MS would become superior. Conclusion: This ex-ante cost evaluation of IM-MS RT showed that the upfront costs of locoregional RT are easily compensated for by avoiding the costs of treating locoregional and distant relapse at a later stage. The cost-sparing effect of RT should, however, be evaluated for a sufficiently long time span and is most specifically found in tumors with a rather slow natural history and a multitude of available systemic treatments at relapse, such as breast cancer

  10. Cost minimisation analysis: kilovoltage imaging with automated repositioning versus electronic portal imaging in image-guided radiotherapy for prostate cancer.

    Science.gov (United States)

    Gill, S; Younie, S; Rolfo, A; Thomas, J; Siva, S; Fox, C; Kron, T; Phillips, D; Tai, K H; Foroudi, F

    2012-10-01

    To compare the treatment time and cost of prostate cancer fiducial marker image-guided radiotherapy (IGRT) using orthogonal kilovoltage imaging (KVI) and automated couch shifts and orthogonal electronic portal imaging (EPI) and manual couch shifts. IGRT treatment delivery times were recorded automatically on either unit. Costing was calculated from real costs derived from the implementation of a new radiotherapy centre. To derive cost per minute for EPI and KVI units the total annual setting up and running costs were divided by the total annual working time. The cost per IGRT fraction was calculated by multiplying the cost per minute by the duration of treatment. A sensitivity analysis was conducted to test the robustness of our analysis. Treatment times without couch shift were compared. Time data were analysed for 8648 fractions, 6057 from KVI treatment and 2591 from EPI treatment from a total of 294 patients. The median time for KVI treatment was 6.0 min (interquartile range 5.1-7.4 min) and for EPI treatment it was 10.0 min (interquartile range 8.3-11.8 min) (P value time for EPI was 8.8 min and for KVI was 5.1 min. Treatment time is less on KVI units compared with EPI units. This is probably due to automation of couch shift and faster evaluation of imaging on KVI units. Annual running costs greatly outweigh initial setting up costs and therefore the cost per fraction was less with KVI, despite higher initial costs. The selection of appropriate IGRT equipment can make IGRT practical within radiotherapy departments. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  11. Treatment and technical intervention time analysis of a robotic stereotactic radiotherapy system.

    Science.gov (United States)

    Crop, F; Lacornerie, T; Szymczak, H; Felin, A; Bailleux, C; Mirabel, X; Lartigau, E

    2014-02-01

    The purpose of this study is to obtain a better operational knowledge of Stereotactic Body Radiotherapy (SBRT) treatments with CyberKnife(r). An analysis of both In-room Times (IRT) and technical interventions of 5 years of treatments was performed, during which more than 1600 patients were treated for various indications, including liver (21%), lung (29%), intracranial (13%), head and neck (11%) and prostate (7%). Technical interventions were recorded along with the time of the failure, time to the intervention, and the complexity and duration of the repair. Analyses of Time Between Failures (TBF) and Service Disrupting TBF(disr) were performed. Treatment time data and variability per indication and following different system upgrades were evaluated. Large variations of IRTs were found between indications, but also large variations for each indication. The combination of the time reduction Tool (using Iris(r)) and Improved Stop Handling was of major impact to shortening of treatment times. The first implementation of the Iris collimator alone did not lead to significantly shorter IRTs for us except during prostate treatments. This was mostly due to the addition at the same time of larger rotational compensation for prostate treatments (58 instead of 1.58). Significant differences of duration between the first fraction and following fractions of a treatment, representing the necessity of defining imaging parameters and explanation to patients, were found for liver (12 min) and lung treatments using Xsight(r) Spine (5 min). Liver and lung treatments represent the longest IRT's and involve the largest variability's in IRT. The malfunction rate of the system followed a Weibull distribution with the shape and scale parameters of 0.8 and 39.7. Mean TBF(disr) was 68 work hours. 60 to 80% of the service disrupting interventions were resolved within 30-60 min, 5% required external intervention and 30% occurred in the morning. The presented results can be applied in the

  12. Animation and radiobiological analysis of 3D motion in conformal radiotherapy.

    Science.gov (United States)

    MacKay, R I; Graham, P A; Moore, C J; Logue, J P; Sharrock, P J

    1999-07-01

    To allow treatment plans to be evaluated against the range of expected organ motion and set up error anticipated during treatment. Planning tools have been developed to allow concurrent animation and radiobiological analysis of three dimensional (3D) target and organ motion in conformal radiotherapy. Surfaces fitted to structures outlined on CT studies are projected onto pre-treatment images or onto megavoltage images collected during the patient treatment. Visual simulation of tumour and normal tissue movement is then performed by the application of three dimensional affine transformations, to the selected surface. Concurrent registration of the surface motion with the 3D dose distribution allows calculation of the change in dose to the volume. Realistic patterns of motion can be applied to the structure to simulate inter-fraction motion and set-up error. The biologically effective dose for the structure is calculated for each fraction as the surface moves over the course of the treatment and is used to calculate the normal tissue complication probability (NTCP) or tumour control probability (TCP) for the moving structure. The tool has been used to evaluate conformal therapy plans against set up measurements recorded during patient treatments. NTCP and TCP were calculated for a patient whose set up had been corrected after systematic deviations from plan geometry were measured during treatment, the effect of not making the correction were also assessed. TCP for the moving tumour was reduced if inadequate margins were set for the treatment. Modelling suggests that smaller margins could have been set for the set up corrected during the course of the treatment. The NTCP for the rectum was also higher for the uncorrected set up due to a more rectal tissue falling in the high dose region. This approach provides a simple way for clinical users to utilise information incrementally collected throughout the whole of a patient's treatment. In particular it is possible to

  13. A meta-analysis of the Timing of Chest Radiotherapy in Patients with Limited-stage Small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Hui ZHAO

    2010-09-01

    Full Text Available Background and objective Although evidence for a significant survival benefit of chest radiotherapy has been proven, no conclusion could be drawn regarding the optimal timing of chest radiation. The aim of this study is to explore whether the timing of chest radiation may influence the survival of the patients with limited-stage small-cell lung cancer (LSSCLC by performing a literature-based meta-analysis. Methods By searching Medline, CENTRAL (the Cochrane central register of controlled trials, CBM, and CNKI, et al, we collected both domestic and overseas published documents about randomized trials comparing different timing chest radiotherapy in patients with LS-SCLC. Early chest radiation was regarded as beginning within 30 days after the start of chemotherapy. Random or fixed effect models were applied to conduct meta-analysis on the trials. The combined odds ratio (OR and the 95% confidence interval (CI were calculated to estimate the mortality in 2 or 3 years and toxicity of the two treatments. The statistical heterogeneity was determined by cochran’s Chi-square test (Q test. The Begg’ test was used to determine the publication bias. Results Six trials that included a total of 1 189 patients were analyzed in the meta-analysis 587 patients were in the early radiation group and 602 patients were in the late radiation group. Considering all 6 eligible trials, the overall survival at 2/3 years was not significantly different between early and late chest radiation (OR=0.78, 95%CI: 0.55-1.05, Z=1.68, P=0.093. For the toxicity, no obvious difference was observed for early chest radiotherapy compared with late irradiation in pneumonitis (OR=1.93, 95%CI: 0.97-3.86, P=0.797, esophagitis (OR=1.43, 95%CI: 0.95-2.13, P=0.572 and thrombocytopenia (OR=1.23, 95%CI: 0.88-1.77, P=0.746, respectively. Conclusion No statistical difference was observed in 2/3 years survival and toxicity, including pneumonitis, esophagitis and thrombocytopenia, between

  14. SU-E-T-332: Dosimetric Impact of Photon Energy and Treatment Technique When Knowledge Based Auto-Planning Is Implemented in Radiotherapy of Localized Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Z; Kennedy, A [Sarah Cannon, Nashville, TN (United States); Larsen, E; Grow, A; Hayes, C; Balamucki, C [North Florida Cancer Center, Gainesville, FL (United States); Salmon, H; Thompson, M [Lake City Cancer Center, Lake City, FL (United States)

    2015-06-15

    Purpose: The aim of this study was to investigate the dosimetric impact of the combination of photon energy and treatment technique on radiotherapy of localized prostate cancer when knowledge based planning was used. Methods: A total of 16 patients with localized prostate cancer were retrospectively retrieved from database and used for this study. For each patient, four types of treatment plans with different combinations of photon energy (6X and 10X) and treatment techniques (7-field IMRT and 2-arc VMAT) were created using a prostate DVH estimation model in RapidPlan™ and Eclipse treatment planning system (Varian Medical System). For any beam arrangement, DVH objectives and weighting priorities were generated based on the geometric relationship between the OAR and PTV. Photon optimization algorithm was used for plan optimization and AAA algorithm was used for final dose calculation. Plans were evaluated in terms of the pre-defined dosimetric endpoints for PTV, rectum, bladder, penile bulb, and femur heads. A Student’s paired t-test was used for statistical analysis and p > 0.05 was considered statistically significant. Results: For PTV, V95 was statistically similar among all four types of plans, though the mean dose of 10X plans was higher than that of 6X plans. VMAT plans showed higher heterogeneity index than IMRT plans. No statistically significant difference in dosimetry metrics was observed for rectum, bladder, and penile bulb among plan types. For left and right femur, VMAT plans had a higher mean dose than IMRT plans regardless of photon energy, whereas the maximum dose was similar. Conclusion: Overall, the dosimetric endpoints were similar regardless of photon energy and treatment techniques when knowledge based auto planning was used. Given the similarity in dosimetry metrics of rectum, bladder, and penile bulb, the genitourinary and gastrointestinal toxicities should be comparable among the selections of photon energy and treatment techniques.

  15. Toxicity and dosimetric analysis of non-small cell lung cancer patients undergoing radiotherapy with 4DCT and image-guided intensity modulated radiotherapy: a regional centre's experience.

    Science.gov (United States)

    Livingston, Gareth C; Last, Andrew J; Shakespeare, Thomas P; Dwyer, Patrick M; Westhuyzen, Justin; McKay, Michael J; Connors, Lisa; Leader, Stephanie; Greenham, Stuart

    2016-09-01

    For patients receiving radiotherapy for locally advance non-small cell lung cancer (NSCLC), the probability of experiencing severe radiation pneumonitis (RP) appears to rise with an increase in radiation received by the lungs. Intensity modulated radiotherapy (IMRT) provides the ability to reduce planned doses to healthy organs at risk (OAR) and can potentially reduce treatment-related side effects. This study reports toxicity outcomes and provides a dosimetric comparison with three-dimensional conformal radiotherapy (3DCRT). Thirty curative NSCLC patients received radiotherapy using four-dimensional computed tomography and five-field IMRT. All were assessed for early and late toxicity using common terminology criteria for adverse events. All plans were subsequently re-planned using 3DCRT to the same standard as the clinical plans. Dosimetric parameters for lungs, oesophagus, heart and conformity were recorded for comparison between the two techniques. IMRT plans achieved improved high-dose conformity and reduced OAR doses including lung volumes irradiated to 5-20 Gy. One case each of oesophagitis and erythema (3%) were the only Grade 3 toxicities. Rates of Grade 2 oesophagitis were 40%. No cases of Grade 3 RP were recorded and Grade 2 RP rates were as low as 3%. IMRT provides a dosimetric benefit when compared to 3DCRT. While the clinical benefit appears to increase with increasing target size and increasing complexity, IMRT appears preferential to 3DCRT in the treatment of NSCLC.

  16. Distress associated with radiotherapy for malignant disease: a quantitative analysis based on patients perceptions

    International Nuclear Information System (INIS)

    Munro, A.J.; Biruls, R.; Griffin, A.V.; Thomas, H.; Vallis, K.A.

    1989-01-01

    Distress associated with attendance at a radiotherapy department was assessed in 80 consecutive patients. All patients were interviewed within 24 h of their first fraction of radiotherapy; 31 patients were also interviewed at the end of treatment. The problem identified at first interview as causing the most distress was worry about the effects of disease and its treatment upon the patient's family. At second interview the dominant complaint was of not being allowed to wash. Psychological problems, including anxiety and sleep disturbances, caused more overall distress than did physical symptoms. The method used in this study for eliciting information on the side-effects of therapy is straightforward and has yielded data that are provocative and suggest interesting avenues for further investigation. (author)

  17. Comparative Analysis of Neural Network Training Methods in Real-time Radiotherapy

    Directory of Open Access Journals (Sweden)

    Nouri S.

    2017-03-01

    Full Text Available Background: The motions of body and tumor in some regions such as chest during radiotherapy treatments are one of the major concerns protecting normal tissues against high doses. By using real-time radiotherapy technique, it is possible to increase the accuracy of delivered dose to the tumor region by means of tracing markers on the body of patients. Objective: This study evaluates the accuracy of some artificial intelligence methods including neural network and those of combination with genetic algorithm as well as particle swarm optimization (PSO estimating tumor positions in real-time radiotherapy. Method: One hundred recorded signals of three external markers were used as input data. The signals from 3 markers thorough 10 breathing cycles of a patient treated via a cyber-knife for a lung tumor were used as data input. Then, neural network method and its combination with genetic or PSO algorithms were applied determining the tumor locations using MATLAB© software program. Results: The accuracies were obtained 0.8%, 12% and 14% in neural network, genetic and particle swarm optimization algorithms, respectively. Conclusion: The internal target volume (ITV should be determined based on the applied neural network algorithm on training steps.

  18. Analysis of failure following definitive radiotherapy for invasive transitional cell carcinoma of the bladder

    Energy Technology Data Exchange (ETDEWEB)

    Mameghan, Hedy; Fisher, Richard; Mameghan, Jill; Brook, Susan

    1995-01-15

    Purpose: To assess prognostic factors for bladder relapse and distant failure following definitive radiotherapy for invasive transitional cell carcinoma (TCC) of the bladder. Methods and Materials: Retrospective review of patients treated in the period 1977 to 1990 by definitive radiotherapy. The factors studied included age, sex, T stage, histological grade, tumor multiplicity, ureteric obstruction, total radiation dose, and use of neoadjuvant chemotherapy. The endpoints studied were bladder relapse and distant failure. Results: There were 342 patients with a mean follow-up time of 7.9 years. Bladder relapse was observed in 159 patients. The overall actuarial bladder relapse rate at 5 years was 55% (SE = 3%). Prognostic factors for a higher bladder relapse rate were: tumor multiplicity (p < 0.001), presence of ureteric obstruction (p = 0.001), and higher T stage (p 0.044). Distant failure occurred in 39 patients. The overall actuarial distant failure rate at 5 years was 28% (SE = 3%). Prognostic factors for a higher distant failure rate were: ureteric obstruction (p = 0.003) and higher T stage (p = 0.030). Conclusion: In our study, patients with invasive bladder TCC fell into distinct prognostic groups determined by the three independent factors, ureteric obstruction, tumor multiplicity, and T stage. These factors provided estimated risks of bladder relapse by 5 years which ranged from 34% to 91%. Knowledge of these prognostic factors can help in the selection of patients more suited for bladder preservation by definitive radiotherapy.

  19. Analysis of failure following definitive radiotherapy for invasive transitional cell carcinoma of the bladder

    International Nuclear Information System (INIS)

    Mameghan, Hedy; Fisher, Richard; Mameghan, Jill; Brook, Susan

    1995-01-01

    Purpose: To assess prognostic factors for bladder relapse and distant failure following definitive radiotherapy for invasive transitional cell carcinoma (TCC) of the bladder. Methods and Materials: Retrospective review of patients treated in the period 1977 to 1990 by definitive radiotherapy. The factors studied included age, sex, T stage, histological grade, tumor multiplicity, ureteric obstruction, total radiation dose, and use of neoadjuvant chemotherapy. The endpoints studied were bladder relapse and distant failure. Results: There were 342 patients with a mean follow-up time of 7.9 years. Bladder relapse was observed in 159 patients. The overall actuarial bladder relapse rate at 5 years was 55% (SE = 3%). Prognostic factors for a higher bladder relapse rate were: tumor multiplicity (p < 0.001), presence of ureteric obstruction (p = 0.001), and higher T stage (p 0.044). Distant failure occurred in 39 patients. The overall actuarial distant failure rate at 5 years was 28% (SE = 3%). Prognostic factors for a higher distant failure rate were: ureteric obstruction (p = 0.003) and higher T stage (p = 0.030). Conclusion: In our study, patients with invasive bladder TCC fell into distinct prognostic groups determined by the three independent factors, ureteric obstruction, tumor multiplicity, and T stage. These factors provided estimated risks of bladder relapse by 5 years which ranged from 34% to 91%. Knowledge of these prognostic factors can help in the selection of patients more suited for bladder preservation by definitive radiotherapy

  20. Outcome analysis of 300 prostate cancer patients treated with neoadjuvant androgen deprivation and hypofractionated radiotherapy

    International Nuclear Information System (INIS)

    Higgins, Geoffrey S.; McLaren, Duncan B.; Kerr, Gillian R.; Elliott, Tony; Howard, Grahame

    2006-01-01

    Purpose: Neoadjuvant androgen deprivation and radical radiotherapy is an established treatment for localized prostate carcinoma. This study sought to analyze the outcomes of patients treated with relatively low-dose hypofractionated radiotherapy. Methods and Materials: Three hundred patients with T1-T3 prostate cancer were treated between 1996 and 2001. Patients were prescribed 3 months of neoadjuvant androgen deprivation before receiving 5250 cGy in 20 fractions. Patients' case notes and the oncology database were used to retrospectively assess outcomes. Median follow-up was 58 months. Results: Patients presented with prostate cancer with poorer prognostic indicators than that reported in other series. At 5 years, the actuarial cause-specific survival rate was 83.2% and the prostate-specific antigen (PSA) relapse rate was 57.3%. Metastatic disease had developed in 23.4% of patients. PSA relapse continued to occur 5 years from treatment in all prognostic groups. Independent prognostic factors for relapse included treatment near the start of the study period, neoadjuvant oral anti-androgen monotherapy rather than neoadjuvant luteinizing hormone releasing hormone therapy, and diagnosis through transurethral resection of the prostate rather than transrectal ultrasound. Conclusion: This is the largest reported series of patients treated with neoadjuvant androgen deprivation and hypofractionated radiotherapy in the United Kingdom. Neoadjuvant hormonal therapy did not appear to adequately compensate for the relatively low effective radiation dose used

  1. Treatment results and prognostic analysis of 47 patients with urethral transitional cell carcinoma treated with post-operative adjuvant radiotherapy

    International Nuclear Information System (INIS)

    He Ke; Hou Xiaorong; Shen Jie; Lian Xin; Sun Shuai; Zhang Fuquan

    2010-01-01

    Objective: To evaluate treatment results and prognostic factors of 47 patients with primary urethral transitional cell carcinoma treated with post-operative adjuvant radiotherapy. Methods: From October 1998 to October 2008, 47 patients with primary urethral transitional cell carcinoma received postoperative adjuvant radiotherapy. Thirty-one patients had stage T 3 /T 4 disease, 7 had lymph node metastasis. Thirty-nine patients had G3 tumor, 13 had stump-positive. The median radiotherapy dose was 60 Gy (36-64 Gy). 81% patients (38/47) were treated with regional irradiation. Results: The median follow-up time was 21 months (6 -88 months). The follow-up rate was 92%. The median overall survival time was 35 months (5 -88 months). The 2-and 5-year overall survival rates were 57% and 49%, respectively. In univariate analysis, the median overall survival time was better in patients with stage T 1 or T 2 compared with stage T 3 or T 4 tumor (42 months vs. 19 months, χ 2 =7.28, P=0.007), with age of ≤65 years compared with >65 years (28 mouths vs 18 months,χ 2 =8.23, P =0.004). There was no significant difference in the long term survival in patients with non-radical surgery compared with radical mastectomy (21 months vs. 20 months, χ 2 = 0.90, P = 0.344). In multivariate analysis, the stage T 3 or T 4 (χ 2 = 7.89, P =0.005), >65 years old (χ 2 = 4.85, P = 0.028), renal pelvis involvement (χ 2 = 5.65, P = 0.018), and tumor located in the mid or inferior segment (χ 2 =6.08,P =0.014) were factors associated with poorer prognosis. Conclusions: Postoperative adjuvant radiotherapy can improve the efficacy of patients with locally advanced urethral transitional cell carcinoma. Advanced T stage and > 65 years age are associated with poorer prognosis. (authors)

  2. Association of anorectal dose-volume histograms and impaired fecal continence after 3D conformal radiotherapy for carcinoma of the prostate

    International Nuclear Information System (INIS)

    Vordermark, Dirk; Schwab, Michael; Ness-Dourdoumas, Rhea; Sailer, Marco; Flentje, Michael; Koelbl, Oliver

    2003-01-01

    Purpose: The late toxicity of fecal incontinence after pelvic radiotherapy is now frequently recognized but the etiology poorly understood. We therefore investigated associations between dose-volume histogram (DVH) parameters of the rectum and the anal canal with fecal continence as measured by an established 10-item questionnaire. Methods and materials: Forty-four patients treated for carcinoma of the prostate with 58-72 Gy of 3D conformal radiotherapy between 1995 and 1999 who completed the questionnaire formed the study population. Total continence scores of treated patients obtained 1.5 years (median) after radiotherapy were compared to a control group of 30 patients before radiotherapy. Median, mean, minimum and maximum doses as well as the volume (% and ml) treated to 40, 50, 60 and 70 Gy were determined separately for anal canal and rectum. DVH parameters were correlated with total continence score (Spearman rank test) and patients grouped according to observed continence were compared regarding DVH values (Mann-Whitney U-test). Results: Median fecal continence scores were significantly worse in the irradiated than in the control group (31 vs. 35 of a maximum 36 points). In treated patients, 59%/27%/14% were classified as fully continent, slightly incontinent and severely incontinent. Continence was similar in the 58-to-62-Gy, 66-Gy and 68-to-72-Gy dose groups. No DVH parameter was significantly correlated with total continence score, but severely incontinent patients had a significantly higher minimum dose to the anal canal than fully continent/slightly incontinent, accompanied by portals extending significantly further inferiorly with respect to the ischial tuberosities. Conclusions: Excluding the inferior part of the anal canal from the treated volume in 3D conformal therapy for carcinoma of the prostate appears to be a promising strategy to prevent radiation-induced fecal incontinence

  3. Dosimetric explanations of fatigue in head and neck radiotherapy: An analysis from the PARSPORT Phase III trial

    International Nuclear Information System (INIS)

    Gulliford, Sarah L.; Miah, Aisha B.; Brennan, Sinead; McQuaid, Dualta; Clark, Catharine H.; Partridge, Mike; Harrington, Kevin J.; Morden, James P.; Hall, Emma; Nutting, Christopher M.

    2012-01-01

    Background: An unexpected finding from the phase III parotid sparing radiotherapy trial, PARSPORT (ISRCTN48243537, CRUK/03/005), was a statistically significant increase in acute fatigue for those patients who were treated with intensity-modulated radiotherapy (IMRT) compared to standard conventional radiotherapy (CRT). One possible explanation was the difference in dose to central nervous system (CNS) structures due to differing beam portals. Using data from the trial, a dosimetric analysis of individual CNS structures was performed. Method: Dosimetric and toxicity data were available for 67 patients (27 CRT, 40 IMRT). Retrospective delineation of the posterior fossa, brainstem, cerebellum, pituitary gland, pineal gland, hypothalamus, hippocampus and basal ganglia was performed. Dosimetry was reviewed using summary statistics and dose–volume atlases. Results: A statistically significant increase in maximum and mean doses to each structure was observed for patients who received IMRT compared to those who received CRT. Both maximum and mean doses were significantly higher for the posterior fossa, brainstem and cerebellum for the 42 patients who reported acute fatigue of Grade 2 or higher (p ⩽ 0.01) compared to the 25 who did not. Dose–volume atlases of the same structures indicated that regions representing larger volumes and higher doses to each structure were consistent with a higher incidence of acute fatigue. There was no association between the dose distribution and acute fatigue for the other structures tested. Conclusions: The excess fatigue reported in the IMRT arm of the trial may, at least in part, be attributed to the dose distribution to the posterior fossa, cerebellum and brainstem. Future studies that modify dose delivery to these structures may allow us to test the hypothesis that radiation-induced fatigue is avoidable.

  4. Detailed review and analysis of complex radiotherapy clinical trial planning data: Evaluation and initial experience with the SWAN software system

    International Nuclear Information System (INIS)

    Ebert, Martin A.; Haworth, Annette; Kearvell, Rachel; Hooton, Ben; Coleman, Rhonda; Spry, Nigel; Bydder, Sean; Joseph, David

    2008-01-01

    Aim: Contemporary radiotherapy clinical trials typically require complex three-dimensional (3D) treatment planning. This produces large amounts of data relating technique and dose delivery for correlation with patient outcomes. Assessment of the quality of this information is required to ensure protocol compliance, to quantify the variation in treatments given to patients and to enhance the power of studies to determine correlates of patient outcomes. Materials and methods: A software system ('SWAN') was developed to facilitate the objective analysis, quality-assurance and review of digital treatment planning data from multi-centre radiotherapy trials. The utility of this system was assessed on the basis of its functionality and our experience of its use in the context of multi-centre clinical trials and trials-support activities. Results: The SWAN system has been shown to have the functionality required for use in several multi-centre trials, including automated review and archive processes. Approximately 800 treatment plans from over 30 participating institutions have so far been assessed with the system for several treatment planning scenarios. To illustrate this we include a description of the use of the system for a large-recruitment prostate radiotherapy trial being undertaken in Australasia, including examples of how the review process has changed clinical practice. Conclusion: The successful implementation of SWAN has been demonstrated in a number of clinical trials. The software provides an opportunity for comprehensive review of treatment parameters that could impact on clinical outcomes and trial results. Such quality-assurance (QA) has previously been difficult or impossible to achieve, particularly for a clinical trial involving large numbers of patients. Such reviews have highlighted inconsistencies in clinical practice that have since been addressed through feedback from the review process. The process of data collection and review should be

  5. A prospective observational trial on emesis in radiotherapy: Analysis of 1020 patients recruited in 45 Italian radiation oncology centres

    International Nuclear Information System (INIS)

    Maranzano, Ernesto; De Angelis, Verena; Pergolizzi, Stefano; Lupattelli, Marco; Frata, Paolo; Spagnesi, Stefano; Frisio, Maria Luisa; Mandoliti, Giovanni; Malinverni, Giuseppe; Trippa, Fabio; Fabbietti, Letizia; Parisi, Salvatore; Di Palma, Annamaria; De Vecchi, Pietro; De Renzis, Costantino; Giorgetti, Celestino; Bergami, Tiziano; Orecchia, Roberto; Portaluri, Maurizio; Signor, Marco

    2010-01-01

    Purpose: A prospective observational multicentre trial was carried out to assess the incidence, pattern, and prognostic factors of radiation-induced emesis (RIE), and to evaluate the use of antiemetic drugs in patients treated with radiotherapy or concomitant radio-chemotherapy. The application in clinical practice of the Multinational Association of Supportive Care in Cancer guidelines was also studied. Materials and methods: Forty-five Italian radiation oncology centres took part in this trial. The accrual lasted for 3 consecutive weeks and only patients starting radiotherapy or concomitant radio-chemotherapy in this period were enrolled. Evaluation was based on diary card filled in daily by patients during treatment and one week after stopping it. Diary card recorded the intensity of nausea/vomiting and prophylactic/symptomatic antiemetic drug prescriptions. Results: A total of 1020 patients entered into the trial, and 1004 were evaluable. Vomiting and nausea occurred in 11.0% and 27.1% of patients, respectively, and 27.9% patients had both vomiting and nausea. In multifactorial analysis, the only statistically significant patient-related risk factors were concomitant chemotherapy and previous experience of vomiting induced by chemotherapy. Moreover, two radiotherapy-related factors were significant risk factors for RIE, the irradiated site (upper abdomen) and field size (>400 cm 2 ). An antiemetic drug was given only to a minority (17%) of patients receiving RT, and the prescriptions were prophylactic in 12.4% and symptomatic in 4.6%. Different compounds and a wide range of doses and schedules were used. Conclusions: These data were similar to those registered in our previous observational trial, and the radiation oncologists' attitude in underestimating RIE and under prescribing antiemetics was confirmed.

  6. MMCTP: a radiotherapy research environment for Monte Carlo and patient-specific treatment planning

    International Nuclear Information System (INIS)

    Alexander, A; DeBlois, F; Stroian, G; Al-Yahya, K; Heath, E; Seuntjens, J

    2007-01-01

    Radiotherapy research lacks a flexible computational research environment for Monte Carlo (MC) and patient-specific treatment planning. The purpose of this study was to develop a flexible software package on low-cost hardware with the aim of integrating new patient-specific treatment planning with MC dose calculations suitable for large-scale prospective and retrospective treatment planning studies. We designed the software package 'McGill Monte Carlo treatment planning' (MMCTP) for the research development of MC and patient-specific treatment planning. The MMCTP design consists of a graphical user interface (GUI), which runs on a simple workstation connected through standard secure-shell protocol to a cluster for lengthy MC calculations. Treatment planning information (e.g., images, structures, beam geometry properties and dose distributions) is converted into a convenient MMCTP local file storage format designated, the McGill RT format. MMCTP features include (a) DICOM R T, RTOG and CADPlan CART format imports; (b) 2D and 3D visualization views for images, structure contours, and dose distributions; (c) contouring tools; (d) DVH analysis, and dose matrix comparison tools; (e) external beam editing; (f) MC transport calculation from beam source to patient geometry for photon and electron beams. The MC input files, which are prepared from the beam geometry properties and patient information (e.g., images and structure contours), are uploaded and run on a cluster using shell commands controlled from the MMCTP GUI. The visualization, dose matrix operation and DVH tools offer extensive options for plan analysis and comparison between MC plans and plans imported from commercial treatment planning systems. The MMCTP GUI provides a flexible research platform for the development of patient-specific MC treatment planning for photon and electron external beam radiation therapy. The impact of this tool lies in the fact that it allows for systematic, platform

  7. Extracting the normal lung dose–response curve from clinical DVH data: a possible role for low dose hyper-radiosensitivity, increased radioresistance

    International Nuclear Information System (INIS)

    Gordon, J J; Snyder, K; Zhong, H; Barton, K; Sun, Z; Chetty, I J; Matuszak, M; Ten Haken, R K

    2015-01-01

    In conventionally fractionated radiation therapy for lung cancer, radiation pneumonitis’ (RP) dependence on the normal lung dose-volume histogram (DVH) is not well understood. Complication models alternatively make RP a function of a summary statistic, such as mean lung dose (MLD). This work searches over damage profiles, which quantify sub-volume damage as a function of dose. Profiles that achieve best RP predictive accuracy on a clinical dataset are hypothesized to approximate DVH dependence.Step function damage rate profiles R(D) are generated, having discrete steps at several dose points. A range of profiles is sampled by varying the step heights and dose point locations. Normal lung damage is the integral of R(D) with the cumulative DVH. Each profile is used in conjunction with a damage cutoff to predict grade 2 plus (G2+) RP for DVHs from a University of Michigan clinical trial dataset consisting of 89 CFRT patients, of which 17 were diagnosed with G2+ RP.Optimal profiles achieve a modest increase in predictive accuracy—erroneous RP predictions are reduced from 11 (using MLD) to 8. A novel result is that optimal profiles have a similar distinctive shape: enhanced damage contribution from low doses (<20 Gy), a flat contribution from doses in the range ∼20–40 Gy, then a further enhanced contribution from doses above 40 Gy. These features resemble the hyper-radiosensitivity / increased radioresistance (HRS/IRR) observed in some cell survival curves, which can be modeled using Joiner’s induced repair model.A novel search strategy is employed, which has the potential to estimate RP dependence on the normal lung DVH. When applied to a clinical dataset, identified profiles share a characteristic shape, which resembles HRS/IRR. This suggests that normal lung may have enhanced sensitivity to low doses, and that this sensitivity can affect RP risk. (paper)

  8. The analysis of stress reactions ana coping patterns of cancer patients who perceived stress by radiotherapy

    International Nuclear Information System (INIS)

    Bang, Dong Han; Kim, Jin Su; Park, Gil Yong; Son, Mi Suk

    2001-01-01

    This study is performed to encourage cancer patients to identify, relieve and effectively overcome the stress caused by radiotherapy, by analyzing stress reactions and coping patterns of cancer patients who perceived stress due to radiotherapy. The study group was composed of 85 cancer patients of the age 20 or higher who were undergoing radiotherapy in four hospitals located in Seoul and Kyonggi-do. The survey questionnaire was used, which had 161 questions inquiring respondents of general status, perceived stress, stress reactions and coping patterns. The surveyed data were analyzed by a SAS program, which employed descriptive statistics. Pearson Correlation Coefficient, t-test, ANOVA and Stepwised Multiple Regression. The stress perception and reaction rates were low in cancer patients comparing to patients of the other study. In the coping patterns. the problem-focused coping patterns were significantly higher than emotion-focused coping patterns. The statistically meaningful differences were observed in the stress perception and reactions depending on the time of diagnosis and perceived health level. As for the problem-focused coping patterns, significant differences were found depending on age, marital status, education, income and the number of family members as well as perceived health level of patients. The level of perceived stress and that of stress reactions was found to have positively significant correlation(r=.764, p<.001) while the perceived stress and the problem-focused coping patterns was correlated negatively (r=-.288, p<.01). The stress reactions and the problem-focused coping patterns was found to have negatively significant correlation(r=-.289, p<.01). The problem-focused coping behavior, which cooperated with doctors, technologists, nurses and families of cancer patients, is advisable for the cancer patients to overcome uncertainty and uneasiness by effectively release the stress.

  9. The analysis of stress reactions ana coping patterns of cancer patients who perceived stress by radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Bang, Dong Han; Kim, Jin Su; Park, Gil Yong; Son, Mi Suk [Dept. of Radiation Oncology, Bundang CHA General Hospital, College of Medicine, Pochon CHA University, Sungnam (Korea, Republic of)

    2001-12-15

    This study is performed to encourage cancer patients to identify, relieve and effectively overcome the stress caused by radiotherapy, by analyzing stress reactions and coping patterns of cancer patients who perceived stress due to radiotherapy. The study group was composed of 85 cancer patients of the age 20 or higher who were undergoing radiotherapy in four hospitals located in Seoul and Kyonggi-do. The survey questionnaire was used, which had 161 questions inquiring respondents of general status, perceived stress, stress reactions and coping patterns. The surveyed data were analyzed by a SAS program, which employed descriptive statistics. Pearson Correlation Coefficient, t-test, ANOVA and Stepwised Multiple Regression. The stress perception and reaction rates were low in cancer patients comparing to patients of the other study. In the coping patterns. the problem-focused coping patterns were significantly higher than emotion-focused coping patterns. The statistically meaningful differences were observed in the stress perception and reactions depending on the time of diagnosis and perceived health level. As for the problem-focused coping patterns, significant differences were found depending on age, marital status, education, income and the number of family members as well as perceived health level of patients. The level of perceived stress and that of stress reactions was found to have positively significant correlation(r=.764, p<.001) while the perceived stress and the problem-focused coping patterns was correlated negatively (r=-.288, p<.01). The stress reactions and the problem-focused coping patterns was found to have negatively significant correlation(r=-.289, p<.01). The problem-focused coping behavior, which cooperated with doctors, technologists, nurses and families of cancer patients, is advisable for the cancer patients to overcome uncertainty and uneasiness by effectively release the stress.

  10. Hypofractionated Intensity-Modulated Radiotherapy for Carcinoma of the Prostate: Analysis of Toxicity

    International Nuclear Information System (INIS)

    Coote, Joanna H.; Wylie, James P.; Cowan, Richard A.; Logue, John P.; Swindell, Ric; Livsey, Jacqueline E.

    2009-01-01

    Purpose: Dose escalation for prostate cancer improves biological control but with a significant increase in late toxicity. Recent estimates of low α/β ratio for prostate cancer suggest that hypofractionation may result in biological advantage. Intensity-modulated radiotherapy (IMRT) should enable dose escalation to the prostate while reducing toxicity to local organs. We report late toxicity data of a hypofractionated IMRT regime. Methods and Materials: Eligible men had T2-3N0M0 adenocarcinoma prostate, and either Gleason score ≥ 7 or prostate-specific antigen 20-50 ng/L. Patients received 57-60 Gy to prostate in 19-20 fractions using five-field IMRT. All received hormonal therapy for 3 months before radiotherapy to a maximum of 6 months. Toxicity was assessed 2 years postradiotherapy using the RTOG criteria, LENT/SOMA, and UCLA prostate index assessment tools. Results: Acute toxicity was favorable with no RTOG Grade 3 or 4 toxicity. At 2 years, there was 4% Grade 2 bowel and 4.25% Grade 2 bladder toxicity. There was no Grade 3 or 4 bowel toxicity; one patient developed Grade 3 bladder toxicity. UCLA data showed a slight improvement in urinary function at 2 years compared with pretreatment. LENT/SOMA assessments demonstrated general worsening of bowel function at 2 years. Patients receiving 60 Gy were more likely to develop problems with bowel function than those receiving 57 Gy. Conclusions: These data demonstrate that hypofractionated radiotherapy using IMRT for prostate cancer is well tolerated with minimal late toxicity at 2 years posttreatment. Ongoing studies are looking at the efficacy of hypofractionated regimes with respect to biological control.

  11. Early Expansion of the Intracranial CSF Volume After Palliative Whole-Brain Radiotherapy: Results of a Longitudinal CT Segmentation Analysis

    International Nuclear Information System (INIS)

    Sanghera, Paul; Gardner, Sandra L.; Scora, Daryl; Davey, Phillip

    2010-01-01

    Purpose: To assess cerebral atrophy after radiotherapy, we measured intracranial cerebrospinal fluid volume (ICSFV) over time after whole-brain radiotherapy (WBRT) and compared it with published normal-population data. Methods and Materials: We identified 9 patients receiving a single course of WBRT (30 Gy in 10 fractions over 2 weeks) for ipsilateral brain metastases with at least 3 years of computed tomography follow-up. Segmentation analysis was confined to the tumor-free hemi-cranium. The technique was semiautomated by use of thresholds based on scanned image intensity. The ICSFV percentage (ratio of ICSFV to brain volume) was used for modeling purposes. Published normal-population ICSFV percentages as a function of age were used as a control. A repeated-measures model with cross-sectional (between individuals) and longitudinal (within individuals) quadratic components was fitted to the collected data. The influence of clinical factors including the use of subependymal plate shielding was studied. Results: The median imaging follow-up was 6.25 years. There was an immediate increase (p < 0.0001) in ICSFV percentage, which decelerated over time. The clinical factors studied had no significant effect on the model. Conclusions: WBRT immediately accelerates the rate of brain atrophy. This longitudinal study in patients with brain metastases provides a baseline against which the potential benefits of more localized radiotherapeutic techniques such as radiosurgery may be compared.

  12. Stereotactic radiotherapy for choroidal melanoma: analysis of eye movement during treatment

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Felipe Marques Lucas de; Gonçalves, Odair Dias; Cardoso, Simone Coutinho, E-mail: felipemlucas@poli.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil); Batista, Delano V.S. [Instituto de Radioproteção e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2017-07-01

    This study aims to analyze the eye’s movement during radiotherapy treatment for choroidal melanoma, as well as the methodology used in the repositioning of the patient between treatments sessions. For this purpose, the procedures used by the hospital staff were analyzed on site and videos were recorded during the treatments. The methodology for the fixation of the eye is correct in its objective. However, the repositioning needs improvements in its reproducibility. It is recommended the study to fix the eye by the healthy eye and the feasibility study for the development of a software that assists in patient repositioning. (author)

  13. Stereotactic radiotherapy for choroidal melanoma: analysis of eye movement during treatment

    International Nuclear Information System (INIS)

    Souza, Felipe Marques Lucas de; Gonçalves, Odair Dias; Cardoso, Simone Coutinho; Batista, Delano V.S.

    2017-01-01

    This study aims to analyze the eye’s movement during radiotherapy treatment for choroidal melanoma, as well as the methodology used in the repositioning of the patient between treatments sessions. For this purpose, the procedures used by the hospital staff were analyzed on site and videos were recorded during the treatments. The methodology for the fixation of the eye is correct in its objective. However, the repositioning needs improvements in its reproducibility. It is recommended the study to fix the eye by the healthy eye and the feasibility study for the development of a software that assists in patient repositioning. (author)

  14. Morphometrical analysis of pathomorphosis of squamous cell lung carcinoma after radiotherapy combined with hyperglycemia

    International Nuclear Information System (INIS)

    Furmanchuk, A.V.; Demidchik, Yu.E.; Khodina, T.V.

    1987-01-01

    Morphological changes are analysed and morphological assessment of the parenchyma, stroma, vessels and necrosis are provided in the squamous cell lung carcinoma tissue of 40 patients without preliminary irradiation, 40 patients after γ-beam therapy and 49 patients after radiotherapy combined with induced hyperglycemia (IH). The total focal dosage was 20 Gy (5 fractions during a week). In 25 patients IH was followed by irradiation and in 24 patients it followed irradiation. Operation was performed on the 7-8th day after therapy was initiated. It was concluded that preoperative γ-beam therapy followed by IH produced the most noticeable damaging effect on squamous cell lung carcinoma

  15. CT simulation in stereotactic brain radiotherapy - analysis of isocenter reproducibility with mask fixation

    International Nuclear Information System (INIS)

    Willner, Jochen; Flentje, Michael; Bratengeier, Klaus

    1997-01-01

    Background and purpose: CT verification and measurement of isocenter deviation using repeated mask fixation in linac-based stereotactic high dose radiotherapy of brain metastases were performed in this study. Materials and methods: For stereotactic radiotherapy of brain metastases a commercial head mask fixation device based on thermoplastic materials (BrainLAB) was used. A two-step planning-treatment procedure was performed. Immediately before treatment the patient was relocated in the mask and a verification CT scan of the radiopaque marked isocenter was performed and if necessary its position was corrected. The verification procedure is described in detail. Twenty-two CT verifications in 16 patients were analyzed. Deviations were measured separately for each direction. A 3D-deviation vector was calculated. Additionally the average amount of deviation in each of the three dimensions was calculated. Results: The mean deviation and standard deviation (SD) of the isocenter was 0.4 mm (SD 1.5 mm) in the longitudinal direction, -0.1 mm (SD 1.8 mm) in the lateral direction and 0.1 mm (SD 1.2 mm) in the anterior-posterior direction. The mean three-dimensional distance (3D-vector) between the verified and the corrected isocenter was 2.4 mm (SD 1.3 mm). The average deviation (without consideration of direction) was 1.1 mm (SD 1.1 mm), 1.3 mm (SD 1.3 mm) and 0.8 mm (SD 0.9 mm) in the longitudinal, lateral and sagittal directions, respectively. No correlation was found between 3D-deviation and the distance of the isocenter from the reference plane nor between deviation and the position of metastases in the brain (central versus peripheral or between different lobes), or the date of treatment. Conclusion: Reproducibility of the isocenter using the presented mask fixation is in the range of positioning reproducibility reported for other non-invasive fixation devices for stereotactic brain treatment. Our results underline the importance of CT verification as a quality

  16. Histopathological effects of intraoperative radiotherapy on pancreas and adjacent tissues: a postmortem analysis

    International Nuclear Information System (INIS)

    Hoekstra, H.J.; Restrepo, C.; Kinsella, T.J.; Sindelar, W.F.

    1988-01-01

    Intraoperative radiotherapy (IORT) has been utilized in the treatment of resectable and unresectable pancreatic carcinoma at the National Cancer Institute. Detailed autopsy analyses of the radiation effects on the pancreas and adjacent tissues were performed on 13 patients dying at various times following therapy. IORT can induce a progressive retroperitoneal fibrosis and fibrosis of the porta hepatis in patients with resectable pancreatic carcinoma. In unresectable pancreatic carcinoma, the major expression of intraoperative irradiation with external beam irradiation is a progressive fibrosis of the pancreas with vascular sclerosis, nerve degeneration, atrophy of acinar cells, and atypical changes in the ducts of the pancreas, as well as degenerative changes of the pancreatic tumor

  17. Analysis of 5 year survival of esophageal cancer treated by radiotherapy

    International Nuclear Information System (INIS)

    Takegawa, Yoshihiro; Ohgushi, Ikuyo; Hiraki, Yoshio; Honke, Yoshifumi; Matsuki, Tsutomu; Yokoyama, Takashi; Yoshida, Mineo.

    1987-01-01

    Since 1984, a total of 1,419 patients with carcinoma of the esophagus were treated at the Department of Radiology of 17 hospitals in Chugoku-Shikoku province. The five year survival rate was 7.3 % (42/578 cases). Thirty-nine out of the forty-two cases were analyzed according to the tumor extent, localization and types of the X-ray findings. In addition, 95 patients (67 had been reported in other journals and 28 in this report) who have survived more than 5 years after radical radiotherapy were analyzed. (author)

  18. Stereotactic radiotherapy for choroidal melanoma: analysis of eye movement during treatment

    Science.gov (United States)

    Souza, F. M. L.; Gonçalves, O. D.; Batista, D. V. S.; Cardoso, S. C.

    2018-03-01

    This study aims to analyse the eye’s movement during radiotherapy treatment for choroidal melanoma, as well as the methodology used in the repositioning of the patient between treatments sessions. For this purpose, the procedures used by the hospital staff were analysed on site and videos were recorded during the treatments. The methodology for the fixation of the eye is correct in its objective. However, the repositioning needs improvements in its reproducibility. It is recommended the study to fix the eye by the healthy eye and the feasibility study for the development of a software that assists in patient repositioning.

  19. Bibliometrics of intraoperative radiotherapy. Analysis of technology, practice and publication tendencies

    Energy Technology Data Exchange (ETDEWEB)

    Sole, Claudio V. [Instituto de Radiomedicina, Service of Radiation Oncology, Santiago (Chile); School of Medicine Complutense University, Madrid (Spain); Institut Gustave Roussy, Department of Radiation Oncology, Paris (France); Calvo, Felipe A. [School of Medicine Complutense University, Madrid (Spain); Hospital General Universitario Gregorio Maranon, Department of Oncology, Madrid (Spain); Hospital General Universitario Gregorio Maranon, Institute for Sanitary Research, Madrid (Spain); Ferrer, Carlos [Hospital Provincial de Castellon, Institute of Oncology, Castellon de la Plana (Spain); Cardenal Herrera-CEU University, School of Medicine, Castellon de la Plana (Spain); Pascau, Javier [Hospital General Universitario Gregorio Maranon, Institute for Sanitary Research, Madrid (Spain); Marsiglia, Hugo [Institut Gustave Roussy, Department of Radiation Oncology, Paris (France)

    2014-12-15

    To analyze the performance and quality of intraoperative radiation therapy (IORT) publications identified in medical databases during a recent period in terms of bibliographic metrics. A bibliometric search was conducted for IORT papers published in the PubMed database between 1997 and 2013. Publication rate was used as a quantity indicator; the 2012 Science Citation Index Impact Factor as a quality indicator. Furthermore, the publications were stratified in terms of study type, scientific topic reported, year of publication, tumor type and journal specialty. We performed a one-way analysis of variance (ANOVA) to determine differences between the means of the analyzed groups. Among the total of 207 journals, articles were reported significantly more frequently in surgery (n = 399, 41 %) and radiotherapy journals (n = 273, 28 %; p < 0.01). The highest impact factor was achieved by clinical oncology journals (p < 0.01). The majority of identified articles were retrospective cohort reports (n = 622, 64 %), followed by review articles (n = 204, 21 %; p < 0.001). Regarding primary topic, reports on cancer outcome following specific tumor therapy were most frequently published (n = 661, 68 %; p < 0.001) and gained the highest mean impact factor (p < 0.01). Gastrointestinal tumor reports were represented most frequently (n = 456, 47 %; p < 0.001) and the mean superior impact factor was earned by breast and gynecologic publications (p < 0.01). We identified a consistent and sustained scientific productivity of international IORT expert groups. Most publications appeared in journals with surgical and radiooncological content. The highest impact factor was achieved by medical oncology journals. (orig.) [German] Ziel war es, in Form von bibliographischen Metriken die wissenschaftliche Effizienz und Qualitaet von Publikationen ueber die Anwendung intraoperativer Strahlentherapie (IORT) zu analysieren, die in einer bestimmten Zeitspanne in medizinischen Datenbanken gefunden

  20. Multivariate analysis for the estimation of target localization errors in fiducial marker-based radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Takamiya, Masanori [Department of Nuclear Engineering, Graduate School of Engineering, Kyoto University, Kyoto 606-8501, Japan and Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto 606-8507 (Japan); Nakamura, Mitsuhiro, E-mail: m-nkmr@kuhp.kyoto-u.ac.jp; Akimoto, Mami; Ueki, Nami; Yamada, Masahiro; Matsuo, Yukinori; Mizowaki, Takashi; Hiraoka, Masahiro [Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto 606-8507 (Japan); Tanabe, Hiroaki [Division of Radiation Oncology, Institute of Biomedical Research and Innovation, Kobe 650-0047 (Japan); Kokubo, Masaki [Division of Radiation Oncology, Institute of Biomedical Research and Innovation, Kobe 650-0047, Japan and Department of Radiation Oncology, Kobe City Medical Center General Hospital, Kobe 650-0047 (Japan); Itoh, Akio [Department of Nuclear Engineering, Graduate School of Engineering, Kyoto University, Kyoto 606-8501 (Japan)

    2016-04-15

    Purpose: To assess the target localization error (TLE) in terms of the distance between the target and the localization point estimated from the surrogates (|TMD|), the average of respiratory motion for the surrogates and the target (|aRM|), and the number of fiducial markers used for estimating the target (n). Methods: This study enrolled 17 lung cancer patients who subsequently underwent four fractions of real-time tumor tracking irradiation. Four or five fiducial markers were implanted around the lung tumor. The three-dimensional (3D) distance between the tumor and markers was at maximum 58.7 mm. One of the markers was used as the target (P{sub t}), and those markers with a 3D |TMD{sub n}| ≤ 58.7 mm at end-exhalation were then selected. The estimated target position (P{sub e}) was calculated from a localization point consisting of one to three markers except P{sub t}. Respiratory motion for P{sub t} and P{sub e} was defined as the root mean square of each displacement, and |aRM| was calculated from the mean value. TLE was defined as the root mean square of each difference between P{sub t} and P{sub e} during the monitoring of each fraction. These procedures were performed repeatedly using the remaining markers. To provide the best guidance on the answer with n and |TMD|, fiducial markers with a 3D |aRM ≥ 10 mm were selected. Finally, a total of 205, 282, and 76 TLEs that fulfilled the 3D |TMD| and 3D |aRM| criteria were obtained for n = 1, 2, and 3, respectively. Multiple regression analysis (MRA) was used to evaluate TLE as a function of |TMD| and |aRM| in each n. Results: |TMD| for n = 1 was larger than that for n = 3. Moreover, |aRM| was almost constant for all n, indicating a similar scale for the marker’s motion near the lung tumor. MRA showed that |aRM| in the left–right direction was the major cause of TLE; however, the contribution made little difference to the 3D TLE because of the small amount of motion in the left–right direction. The TLE

  1. Clinical Outcomes for Patients with Gleason Score 9-10 Prostate Adenocarcinoma Treated With Radiotherapy or Radical Prostatectomy: A Multi-institutional Comparative Analysis.

    Science.gov (United States)

    Kishan, Amar U; Shaikh, Talha; Wang, Pin-Chieh; Reiter, Robert E; Said, Jonathan; Raghavan, Govind; Nickols, Nicholas G; Aronson, William J; Sadeghi, Ahmad; Kamrava, Mitchell; Demanes, David Jeffrey; Steinberg, Michael L; Horwitz, Eric M; Kupelian, Patrick A; King, Christopher R

    2017-05-01

    The long natural history of prostate cancer (CaP) limits comparisons of efficacy between radical prostatectomy (RP) and external beam radiotherapy (EBRT), since patients treated years ago received treatments considered suboptimal by modern standards (particularly with regards to androgen deprivation therapy [ADT] and radiotherapy dose-escalation]. Gleason score (GS) 9-10 CaP is particularly aggressive, and clinically-relevant endpoints occur early, facilitating meaningful comparisons. To compare outcomes of patients with GS 9-10 CaP following EBRT, extremely-dose escalated radiotherapy (as exemplified by EBRT+brachytherapy [EBRT+BT]), and RP. Retrospective analysis of 487 patients with biopsy GS 9-10 CaP treated between 2000 and 2013 (230 with EBRT, 87 with EBRT+BT, and 170 with RP). Most radiotherapy patients received ADT and dose-escalated radiotherapy. Kaplan-Meier analysis and multivariate Cox regression estimated and compared 5-yr and 10-yr rates of distant metastasis-free survival, cancer-specific survival (CSS), and overall survival (OS). The median follow-up was 4.6 yr. Local salvage and systemic salvage were performed more frequently in RP patients (49.0% and 30.1%) when compared with either EBRT patients (0.9% and 19.7%) or EBRT+BT patients (1.2% and 16.1%, pRadiotherapy and RP provide equivalent CSS and OS. Extremely dose-escalated radiotherapy with ADT in particular offers improved systemic control when compared with either EBRT or RP. These data suggest that extremely dose-escalated radiotherapy with ADT might be the optimal upfront treatment for patients with biopsy GS 9-10 CaP. While some prostate cancers are slow-growing requiring many years, sometimes decades, of follow-up in order to compare between radiation and surgery, high-risk and very aggressive cancers follow a much shorter time course allowing such comparisons to be made and updated as treatments, especially radiation, rapidly evolve. We showed that radiation-based treatments and surgery

  2. Evaluating quality of life and cost implications of prophylactic radiotherapy in mesothelioma: Health economic analysis of the SMART trial.

    Science.gov (United States)

    Stewart, Samuel Alan; Clive, Amelia O; Maskell, Nick A; Penz, Erika

    2018-01-01

    The SMART trial is a UK-based, multicentre RCT comparing prophylactic radiotherapy and symptom-based (deferred) radiotherapy in 203 patients with Malignant Pleural Mesothelioma who had undergone large bore pleural interventions. Using costs and quality of life data collected alongside the clinical trial, we will estimate the cost-effectiveness of prophylactic radiotherapy compared to deferred radiotherapy over a 1-year period. Healthcare utilization and costs were captured during the trial. Utility weights produced by the EQ-5D questionnaire were used to determine quality-adjusted life-years (QALY) gained. The incremental cost-effectiveness ratio was calculated over the one-year trial period. Costs were similar in the immediate and deferred radiotherapy groups: £5480.40 (SD = £7040; n = 102) and £5461.40 (SD = £7770; n = 101) respectively. There was also no difference in QALY: 0.498 (95% CI: [0.45, 0.547]) in the prophylactic radiotherapy group versus 0.525 (95% CI: [0.471, 0.580]) in the deferred group. At a willingness to pay threshold of £30,000/QALY there was only a 24% chance that prophylactic radiotherapy was cost-effective compared to deferred radiotherapy. There was no significant effect of prophylactic radiotherapy on quality of life in the intervention group, nor was there any discernable decrease in healthcare costs. There is little evidence to suggest that prophylactic radiotherapy is a cost-effective intervention in this population. ISRCTN72767336 with ISRCTN.

  3. A patch-based pseudo-CT approach for MRI-only radiotherapy in the pelvis

    Energy Technology Data Exchange (ETDEWEB)

    Andreasen, Daniel, E-mail: dana@dtu.dk [Department of Applied Mathematics and Computer Science, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark and Radiotherapy Research Unit, Department of Oncology, Gentofte and Herlev Hospital, University of Copenhagen, 2730 Herlev (Denmark); Van Leemput, Koen [Department of Applied Mathematics and Computer Science, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark and A.A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129 (United States); Edmund, Jens M. [Radiotherapy Research Unit, Department of Oncology, Gentofte and Herlev Hospital, University of Copenhagen, 2730 Herlev (Denmark)

    2016-08-15

    Purpose: In radiotherapy based only on magnetic resonance imaging (MRI), knowledge about tissue electron densities must be derived from the MRI. This can be achieved by converting the MRI scan to the so-called pseudo-computed tomography (pCT). An obstacle is that the voxel intensities in conventional MRI scans are not uniquely related to electron density. The authors previously demonstrated that a patch-based method could produce accurate pCTs of the brain using conventional T{sub 1}-weighted MRI scans. The method was driven mainly by local patch similarities and relied on simple affine registrations between an atlas database of the co-registered MRI/CT scan pairs and the MRI scan to be converted. In this study, the authors investigate the applicability of the patch-based approach in the pelvis. This region is challenging for a method based on local similarities due to the greater inter-patient variation. The authors benchmark the method against a baseline pCT strategy where all voxels inside the body contour are assigned a water-equivalent bulk density. Furthermore, the authors implement a parallelized approximate patch search strategy to speed up the pCT generation time to a more clinically relevant level. Methods: The data consisted of CT and T{sub 1}-weighted MRI scans of 10 prostate patients. pCTs were generated using an approximate patch search algorithm in a leave-one-out fashion and compared with the CT using frequently described metrics such as the voxel-wise mean absolute error (MAE{sub vox}) and the deviation in water-equivalent path lengths. Furthermore, the dosimetric accuracy was tested for a volumetric modulated arc therapy plan using dose–volume histogram (DVH) point deviations and γ-index analysis. Results: The patch-based approach had an average MAE{sub vox} of 54 HU; median deviations of less than 0.4% in relevant DVH points and a γ-index pass rate of 0.97 using a 1%/1 mm criterion. The patch-based approach showed a significantly better

  4. Analysis of reproducibility of respiration-triggered gated radiotherapy for lung tumors

    International Nuclear Information System (INIS)

    Spoelstra, Femke O.B.; Soernsen de Koste, John R. van; Cuijpers, Johan P.; Lagerwaard, Frank J.; Slotman, Ben J.; Senan, Suresh

    2008-01-01

    Purpose: Respiration-gated radiotherapy (RGRT) can decrease the toxicity of chemo-radiotherapy (CT-RT) by allowing use of smaller treatment fields. RGRT requires a predictable relationship between tumor position and external surrogate, which must be verified during treatment. Time-integrated electronic portal imaging (TI-EPI) identifies mean intra-fractional positions of moving structures, and was used to study reproducibility of anatomy during RGRT for lung tumors. Materials and methods: TI-EPIs were acquired using an amorphous silicon-based electronic portal imaging system (EPID, aS500) in continuous image acquisition mode in 11 patients treated with audio-coached RGRT at end-inspiration. The Varian Real-time Position Management (RPM) system was used for 4DCT imaging and RGRT delivery. All TI-EPI portals were co-registered to corresponding digitally reconstructed radiographs (DRR) of the planning 4DCT using the spinal column. Displacements in tumor position or that of an adjacent bronchus during RGRT was measured relative to the reference structure on the DRR. Results: Vertebra-matched portals revealed systematic (Σ) and random (σ) errors of 1.8 and 1.3 mm in medial-lateral direction and 1.7 and 1.7 mm in cranial-caudal direction, indicating a reproducible tumor/bronchus position during the RPM-triggered gates. Conclusions: RGRT delivery at end-inspiration can achieve reproducible internal anatomy in 'gated' fields delivered with audio-coaching

  5. Histological analysis of the alterations on cortical bone channels network after radiotherapy: A rabbit study.

    Science.gov (United States)

    Rabelo, Gustavo Davi; Beletti, Marcelo Emílio; Dechichi, Paula

    2010-10-01

    The aim of this study was to evaluate the effects of radiotherapy in cortical bone channels network. Fourteen rabbits were divided in two groups and test group received single dose of 15 Gy cobalt-60 radiation in tibia, bilaterally. The animals were sacrificed and a segment of tibia was removed and histologically processed. Histological images were taken and had their bone channels segmented and called regions of interest (ROI). Images were analyzed through developed algorithms using the SCILAB mathematical environment, getting percentage of bone matrix, ROI areas, ROI perimeters, their standard deviations and Lacunarity. The osteocytes and empty lacunae were also counted. Data were evaluated using Kolmogorov-Smirnov, Mann Whitney, and Student's t test (P < 0.05). Significant differences in bone matrix percentage, area and perimeters of the channels, their respective standard deviations and lacunarity were found between groups. In conclusion, the radiotherapy causes reduction of bone matrix and modifies the morphology of bone channels network. © 2010 Wiley-Liss, Inc.

  6. Adjuvant radiotherapy after extrapleural pneumonectomy for mesothelioma. Prospective analysis of a multi-institutional series

    International Nuclear Information System (INIS)

    Tonoli, Sandro; Vitali, Paola; Scotti, Vieri; Bertoni, Filippo; Spiazzi, Luigi; Ghedi, Barbara; Buonamici, Fabrizio Banci; Marrazzo, Livia; Guidi, Gabriele; Meattini, Icro; Bastiani, Paolo; Amichetti, Maurizio; Schwarz, Marco; Magrini, Stefano Maria

    2011-01-01

    Background and purpose: To evaluate survival, locoregional control and toxicity in a series of 56 mesothelioma patients treated from May 2005 to May 2010 with post-operative radiotherapy after extrapleural pneumonectomy (EPP) in three Italian Institutions (Brescia, Florence, and Modena). Material and methods: Fifty-six patients treated with adjuvant radiotherapy (RT) after EPP were analyzed. Four patients were treated with 3DCRT, 50 with IMRT and two with helical tomotherapy. Forty-five to 50 Gy in 25 fractions were given to the affected hemithorax and to ipsilateral mediastinum, with a simultaneous integrated boost to the sites of microscopically involved margins up to 60 Gy in 20/56 cases. Results: Three year locoregional control (LRC), distant metastasis free (DMF), disease free (DF), disease specific (DSS) and overall survival (OS) rates are 90%, 66%, 57%, 62%, and 60%, respectively. Conclusion: Postoperative RT with modern techniques is an effective method to obtain excellent local control and cure rates in mesothelioma patients submitted to EPP.

  7. SU-F-P-27: The Study of Actual DVH for Target and OARs During the Radiotherapy of Non-Small Cell Lung Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Ma, C; Yin, Y [Shandong Cancer Hospital and Institute, Jinan, Shandong (China)

    2016-06-15

    Purpose: To analyze the changes of the volume and dosimetry of target and organs at risk (OARs) by comparing the daily CBCT images and planning CT images of the patients with Non-Small Cell Lung Cancer (NSCLC) and analyze the difference between planned dose and accumulated dose. Methods: This study retrospectively analyzed eight cases of non-small cell lung cancer patients who accepted CRT or IMRT treatment and KV-CBCT. For each patient, the prescription dose was 60Gy and the fraction dose was 2Gy. Deform the daily CBCT images to planning CT images by the mapping of registration to compare the planning dose with cumulative dose of targets and organs at risk in RayStation. Results: The average volume of GTV of 8 patients with CBCT was 88.26% of the original volume. The average plan dose of GTV was 64.49±2.40Gy. The accumulated dose of GTV was 60.13±2.70Gy (P≤0.05). The average volume of PTV to reach the prescription dose was 95.59% for original plan and 81.47% for accumulated plan (P≤0.05). The volume changes of the left and right lung of the original volume was 88.95% and 80.32%, respectively. The average dose of the left and right lung of original plan was 9.31±1.75Gy and 4.33±1.10Gy, respectively(P≥0.05). The average accumulated dose was 9.63±1.96Gy and 4.63±1.36Gy, respectively(P≥0.05). The average plan dose and accumulated dose of heart was 6.88±1.70Gy and 6.38±0.91Gy, respectively (P≥0.05). The average plan maximum dose and accumulated dose for spinal cord was 24.62±5.91Gy and 26.00±5.14Gy, respectively (P≥0.05). Conclusion: The changes of target anatomical structure with NSCLC make difference between the planned dose and cumulative dose. With the dose deformation method, the dose gap can be found between planning dose and delivery dose.

  8. Adjuvant external beam radiotherapy in the treatment of endometrial cancer (MRC ASTEC and NCIC CTG EN.5 randomised trials): pooled trial results, systematic review, and meta-analysis.

    Science.gov (United States)

    Blake, P; Swart, Ann Marie; Orton, J; Kitchener, H; Whelan, T; Lukka, H; Eisenhauer, E; Bacon, M; Tu, D; Parmar, M K B; Amos, C; Murray, C; Qian, W

    2009-01-10

    Early endometrial cancer with low-risk pathological features can be successfully treated by surgery alone. External beam radiotherapy added to surgery has been investigated in several small trials, which have mainly included women at intermediate risk of recurrence. In these trials, postoperative radiotherapy has been shown to reduce the risk of isolated local recurrence but there is no evidence that it improves recurrence-free or overall survival. We report the findings from the ASTEC and EN.5 trials, which investigated adjuvant external beam radiotherapy in women with early-stage disease and pathological features suggestive of intermediate or high risk of recurrence and death from endometrial cancer. Between July, 1996, and March, 2005, 905 (789 ASTEC, 116 EN.5) women with intermediate-risk or high-risk early-stage disease from 112 centres in seven countries (UK, Canada, Poland, Norway, New Zealand, Australia, USA) were randomly assigned after surgery to observation (453) or to external beam radiotherapy (452). A target dose of 40-46 Gy in 20-25 daily fractions to the pelvis, treating five times a week, was specified. Primary outcome measure was overall survival, and all analyses were by intention to treat. These trials were registered ISRCTN 16571884 (ASTEC) and NCT 00002807 (EN.5). After a median follow-up of 58 months, 135 women (68 observation, 67 external beam radiotherapy) had died. There was no evidence that overall survival with external beam radiotherapy was better than observation, hazard ratio 1.05 (95% CI 0.75-1.48; p=0.77). 5-year overall survival was 84% in both groups. Combining data from ASTEC and EN.5 in a meta-analysis of trials confirmed that there was no benefit in terms of overall survival (hazard ratio 1.04; 95% CI 0.84-1.29) and can reliably exclude an absolute benefit of external beam radiotherapy at 5 years of more than 3%. With brachytherapy used in 53% of women in ASTEC/EN.5, the local recurrence rate in the observation group at 5 years

  9. Individual patient data meta-analysis shows a significant association between the ATM rs1801516 SNP and toxicity after radiotherapy in 5456 breast and prostate cancer patients

    DEFF Research Database (Denmark)

    Andreassen, Christian Nicolaj; Rosenstein, Barry S; Kerns, Sarah L

    2016-01-01

    PURPOSE: Several small studies have indicated that the ATM rs1801516 SNP is associated with risk of normal tissue toxicity after radiotherapy. However, the findings have not been consistent. In order to test this SNP in a well-powered study, an individual patient data meta-analysis was carried ou...

  10. Radiotherapy; Strahlentherapie

    Energy Technology Data Exchange (ETDEWEB)

    Wannenmacher, M. [Heidelberg Univ., Mannheim (Germany). Abt. fuer Klinische Radiologie; Debus, J. [Univ. Heidelberg (Germany). Abt. Radioonkologie und Strahlentherapie; Wenz, F. (eds.) [Universitaetsklinikum Mannheim (Germany). Klinik fuer Strahlentherapie und Radioonkologie

    2006-07-01

    The book is focussed on the actual knowledge on the clinical radiotherapy and radio-oncology. Besides fundamental and general contributions specific organ systems are treated in detail. The book contains the following contributions: Basic principles, radiobiological fundamentals, physical background, radiation pathology, basics and technique of brachytherapy, methodology and technique of the stereotactic radiosurgery, whole-body irradiation, operative radiotherapy, hadron therapy, hpyerthermia, combined radio-chemo-therapy, biometric clinical studies, intensity modulated radiotherapy, side effects, oncological diagnostics; central nervous system and sense organs, head-neck carcinomas, breast cancer, thorax organs, esophagus carcinoma, stomach carcinoma, pancreas carcinoma, heptabiliary cancer and liver metastases, rectal carcinomas, kidney and urinary tract, prostate carcinoma, testicular carcinoma, female pelvis, lymphatic system carcinomas, soft tissue carcinoma, skin cancer, bone metastases, pediatric tumors, nonmalignant diseases, emergency in radio-oncology, supporting therapy, palliative therapy.

  11. Risk of second non-breast cancer after radiotherapy for breast cancer: A systematic review and meta-analysis of 762,468 patients

    International Nuclear Information System (INIS)

    Grantzau, Trine; Overgaard, Jens

    2015-01-01

    Background and purpose: Radiotherapy for breast cancer both decreases loco-regional recurrence rates and improves overall survival. However, radiotherapy has also been associated with increased second cancer risk at exposed sites. In this meta-analysis, we estimated the risk of second non-breast cancers after radiotherapy for breast cancer. Material and methods: The databases Medline/Pubmed, Cochrane, Embase and Cinahl were systematically searched, for cohort studies on second cancer after radiotherapy for breast cancer, from inception to August 1st 2013. Included studies were to report the relative risk (RR) of second cancers comparing irradiated female breast cancer patients to unirradiated patients. Primary endpoints were all second non-breast-cancers and second cancers of the lung, esophagus, thyroid and second sarcomas. RRs were pooled using random-effects meta-analysis. Results: Thirteen studies comprising 762,468 breast cancer patients were included in the meta-analysis. Five or more years after breast cancer diagnosis radiotherapy was significantly associated with an increased risk of second non-breast cancer RR 1.12 (95% confidence interval [CI] 1.06–1.19), second cancer of the lung RR 1.39 (95% CI 1.28–1.51), esophagus RR 1.53 (95% CI 1.01–2.31) and second sarcomas RR 2.53 (95% CI 1.74–3.70). The risk increased over time, and was highest 15 or more years after breast cancer diagnosis, for second lung RR 1.66 (95% CI 1.36–2.01) and second esophagus cancer RR 2.17 (95% CI 1.11–4.25). There was no significant association between radiotherapy and second thyroid cancer. Conclusions: Radiotherapy for breast cancer is significantly associated with increased risks of second non-breast cancer, overall and in organs adjacent to the previous treatment fields. Despite a relative small absolute risk, the growing number of long-time survivors after breast cancer warrants the need for normal tissue sparing radiotherapy techniques

  12. SU-G-TeP3-11: Radiobiological-Cum-Dosimetric Quality Assurance of Complex Radiotherapy Plans

    Energy Technology Data Exchange (ETDEWEB)

    Paudel, N; Narayanasamy, G; Zhang, X; Penagaricano, J; Morrill, S [University of Arkansas for Medical Sciences, Little Rock, AR (United States); Mavroidis, P [University North Carolina, Chapel Hill, NC (United States); Pyakuryal, A [National Cancer Institute, Rockville, MD (United States); Han, E [UT MD Anderson Cancer Center, Houston, TX (United States); Liang, X [University of Florida Health Proton Therapy Institute, Jacksonville, FL (United States); Kim, D [Kyung Hee University Hospital, Seol (Korea, Republic of)

    2016-06-15

    Purpose: Dosimetric gamma-analysis used for QA of complex radiotherapy plans tests the dosimetric equivalence of a delivered plan with the treatment planning system (TPS) optimized plan. It does not examine whether a dosimetric difference results in any radiobiological difference. This study introduces a method to test the radiobiological and dosimetric equivalence between a delivered and the TPS optimized plan. Methods: Six head and neck and seven lung cancer VMAT or IMRT plans optimized for patient treatment were calculated and delivered to an ArcCheck phantom. ArcCheck measured dose distributions were compared with the TPS calculated dose distributions using a 2-D gamma-analysis. Dose volume histograms (DVHs) for various patient structures were obtained by using measured data in 3DVH software and compared against the TPS calculated DVHs using 3-D gamma analysis. DVH data were used in the Poisson model to calculate tumor control probability (TCP) for the treatment targets and in the sigmoid dose response model to calculate normal tissue complication probability (NTCP) for the normal structures. Results: Two-D and three-D gamma passing rates among six H&N patient plans differed by 0 to 2.7% and among seven lung plans by 0.1 to 4.5%. Average ± SD TCPs based on measurement and TPS were 0.665±0.018 and 0.674±0.044 for H&N, and 0.791±0.027 and 0.733±0.031 for lung plans, respectively. Differences in NTCPs were usually negligible. The differences in dosimetric results, TCPs and NTCPs were insignificant. Conclusion: The 2-D and 3-D gamma-analysis based agreement between measured and planned dose distributions may indicate their dosimetric equivalence. Small and insignificant differences in TCPs and NTCPs based on measured and planned dose distributions indicate the radiobiological equivalence between the measured and optimized plans. However, patient plans showing larger differences between 2-D and 3-D gamma-analysis can help us make a more definite conclusion

  13. Chemotherapy followed by low dose radiotherapy in childhood Hodgkin's disease: retrospective analysis of results and prognostic factors

    Directory of Open Access Journals (Sweden)

    Pellizzon Cassio A

    2006-10-01

    Full Text Available Abstract Purpose To report the treatment results and prognostic factors of childhood patients with Hodgkin's disease treated with chemotherapy (CT followed by low dose radiotherapy (RT. Patients and methods This retrospective series analyzed 166 patients under 18 years old, treated from January 1985 to December 2003. Median age was 10 years (range 2–18. The male to female ratio was 2,3 : 1. Lymphonode enlargement was the most frequent clinical manifestation (68%, and the time of symptom duration was less than 6 months in 55% of the patients. In histological analysis Nodular Sclerosis was the most prevalent type (48% followed by Mixed Celularity (34.6%. The staging group according Ann Arbor classification was: I (11.7%, II (36.4%, III (32.1% and IV (19.8%. The standard treatment consisted of chemotherapy multiple drug combination according the period of treatment protocols vigent: ABVD in 39% (n-65 of the cases, by VEEP in 13 %(n-22, MOPP in 13 %(n-22, OPPA-13 %(n-22 and ABVD/OPPA in 22 %(n-33. Radiotherapy was device to all areas of initial presentation of disease. Dose less or equal than 21 Gy was used in 90.2% of patients with most part of them (90% by involved field (IFRT or mantle field. Results The OS and EFS in 10 years were 89% and 87%. Survival according to clinical stage as 94.7%, 91.3%, 82.3% and 71% for stages I to IV(p = 0,005. The OS was in 91.3% of patients who received RT and in 72.6% of patients who did not (p = 0,003. Multivariate analysis showed presence of B symptoms, no radiotherapy and advanced clinical stage to be associated with a worse prognosis. Conclusion This data demonstrating the importance of RT consolidation with low dose and reduced volume, in all clinical stage of childhood HD, producing satisfactory ten years OS and EFS. As the disease is highly curable, any data of long term follow-up should be presented in order to better direct therapy, and to identify groups of patients who would not benefit from radiation

  14. Chemotherapy followed by low dose radiotherapy in childhood Hodgkin's disease: retrospective analysis of results and prognostic factors

    International Nuclear Information System (INIS)

    Viani, Gustavo A; Castilho, Marcus S; Novaes, Paulo E; Antonelli, Celia G; Ferrigno, Robson; Pellizzon, Cassio A; Fogaroli, Ricardo C; Conte, Maria A; Salvajoli, Joao V

    2006-01-01

    To report the treatment results and prognostic factors of childhood patients with Hodgkin's disease treated with chemotherapy (CT) followed by low dose radiotherapy (RT). This retrospective series analyzed 166 patients under 18 years old, treated from January 1985 to December 2003. Median age was 10 years (range 2–18). The male to female ratio was 2,3 : 1. Lymphonode enlargement was the most frequent clinical manifestation (68%), and the time of symptom duration was less than 6 months in 55% of the patients. In histological analysis Nodular Sclerosis was the most prevalent type (48%) followed by Mixed Celularity (34.6%). The staging group according Ann Arbor classification was: I (11.7%), II (36.4%), III (32.1%) and IV (19.8%). The standard treatment consisted of chemotherapy multiple drug combination according the period of treatment protocols vigent: ABVD in 39% (n-65) of the cases, by VEEP in 13 %(n-22), MOPP in 13 %(n-22), OPPA-13 %(n-22) and ABVD/OPPA in 22 %(n-33). Radiotherapy was device to all areas of initial presentation of disease. Dose less or equal than 21 Gy was used in 90.2% of patients with most part of them (90%) by involved field (IFRT) or mantle field. The OS and EFS in 10 years were 89% and 87%. Survival according to clinical stage as 94.7%, 91.3%, 82.3% and 71% for stages I to IV(p = 0,005). The OS was in 91.3% of patients who received RT and in 72.6% of patients who did not (p = 0,003). Multivariate analysis showed presence of B symptoms, no radiotherapy and advanced clinical stage to be associated with a worse prognosis. This data demonstrating the importance of RT consolidation with low dose and reduced volume, in all clinical stage of childhood HD, producing satisfactory ten years OS and EFS. As the disease is highly curable, any data of long term follow-up should be presented in order to better direct therapy, and to identify groups of patients who would not benefit from radiation treatment

  15. Comparative analysis of thermoplastic masks versus vacuum cushions in stereotactic body radiotherapy

    International Nuclear Information System (INIS)

    Navarro-Martin, Arturo; Cacicedo, Jon; Leaman, Olwen; Sancho, Ismael; García, Elvira; Navarro, Valentin; Guedea, Ferran

    2015-01-01

    To compare thermoplastic masks (TMP) and vacuum cushion system (VCS) to assess differences in interfraction set up accuracy in patients treated with stereotactic radiotherapy (SBRT) for oligometastatic lung cancer. Secondarily, to survey radiotherapy technologists to assess their satisfaction with the two systems. Retrospective study of patients treated with lung SBRT between 2008 to 2012 at our institution. Immobilization was performed for 73 treatment sessions (VCS = 40; TMP = 33). A total of 246 cone-beams were analysed. Patients considered ineligible for surgery with a life expectancy ≥6 months and performance status > 1 were included. Target lesion location was verified by cone beam computed tomography (CBCT) prior to each session, with displacements assessed by CBCT simulation prior to each treatment session. Couch shifts were registered prospectively in vertical, longitudinal, and latero-lateral directions to obtain Kernel coordinates (3D representation). Technologists were surveyed to assess their satisfaction with indexing, positioning, and learning curve of the two systems. Setup displacements were obtained in all patients for each treatment plan and for each session. To assess differences between the immobilization systems, a t-test (Welch) was performed. Mean displacements for the TMP and VC systems, respectively, were as follows: session one, 0.64 cm vs 1.05 cm (p = 0.0002); session two, 0.49 cm vs 1.02 cm (p < 0.0001), and session three, 0.56 vs 0.97 cm (p = 0.0011). TMP resulted in significantly smaller shifts vs. VCS in all three treatment sessions. Technologists rated the learning curve, set up, and positioning more highly for TMP versus VCS. Due to the high doses and steep gradients in lung SBRT, accurate and reproducible inter-fraction set up is essential. We found that thermoplastic masks offers better reproducibility with significantly less interfractional set up displacement than vacuum cushions. Moreover, radiotherapy technologists rated

  16. Radiotherapy apparatus

    International Nuclear Information System (INIS)

    Leung, P.M.; Webb, H.P.J.

    1985-01-01

    This invention relates to apparatus for applying intracavitary radiotherapy. In previously-known systems radioactive material is conveyed to a desired location within a patient by transporting a chain of balls pneumatically to and from an appropriately inserted applicator. According to this invention a ball chain for such a purpose comprises several radioactive balls separated by non-radioactive tracer balls of radiographically transparent material of lower density and surface hardness than the radioactive balls. The invention also extends to radiotherapy treatment apparatus comprising a storage, sorting and assembly system

  17. Risk-adapted targeted intraoperative radiotherapy versus whole-breast radiotherapy for breast cancer

    DEFF Research Database (Denmark)

    Vaidya, Jayant S; Wenz, Frederik; Bulsara, Max

    2014-01-01

    The TARGIT-A trial compared risk-adapted radiotherapy using single-dose targeted intraoperative radiotherapy (TARGIT) versus fractionated external beam radiotherapy (EBRT) for breast cancer. We report 5-year results for local recurrence and the first analysis of overall survival....

  18. The curative effects of radiotherapy-based therapies for human epidermal growth factor receptor 2-positive breast cancer: A meta-analysis.

    Science.gov (United States)

    Shao, Minghai; Zhang, Chi; Qin, Qin; Zhang, Zhaoyue; Zhu, Hongcheng; Di, Xiaoke; Sun, Xinchen

    2017-09-01

    This meta-analysis was designed to fully assess the curative effects of radiotherapy-based therapies for human epidermal growth factor receptor 2-positive (HER2+) breast cancer (BC). English articles were retrieved through searching Cochrane library, PubMed, and Embase databases updated to February 2017. Studies were selected based on the inclusion and exclusion criteria. The curative effects of radiotherapy-based therapies forHER2+ BC patients were assessed using hazard rates (HRs) or odds ratios (ORs), as well as their 95% confidence intervals (CIs). In addition, Egger test was used to assess publication bias, followed by sensitivity analysis. All statistic methods were conducted using R 3.12 software. A total of 9 eligible studies were included into this meta-analysis, which involved 2236 HER2+ BC patients. Egger test showed that the eligible studies had no publication bias (t = 2.198, P = .05918). Sensitivity analysis demonstrated that the results were stable. HER2+ BC patients in radiotherapy group had lower locoregional recurrences than those in other groups. Moreover, meta-analysis showed that no significant difference was found between HER2+ BC patients in radiotherapy group and other groups on the 1-year overall survival (P = 0.5263, I = 65.4%), 3-year overall survival (P = 0.4591, I = 0), and 5-year overall survival (P = 0.06277, I = 0). Radiotherapy-based therapies might have certain advantages in treating HER2+ BC patients.

  19. ANALYSIS OF COMPLICATIONS DUE TO INTRATISSUE RADIOTHERAPY USING CONSTANT SOURCES IN PATIENTS WITH PROSTATE CANCER

    Directory of Open Access Journals (Sweden)

    A. V. Petrovsky

    2011-01-01

    Full Text Available Brachytherapy is a standard treatment for localized advanced prostate cancer (PC. Complications due to interstitial radiotherapy using permanent sources were analyzed in 149 patients. The incidence of early grade 3 radiation urethritis was 7.4 % and that of rectitis was 3.4%. Late radiation urethritis and rectitis were recorded in 3.4 and 0.7 %, respectively. Sexual function 12 months later was preserved in 86.6 % of the patients. Studies established no statistically significant factors that influenced the frequency of complications. The patients with a prostate volume of > 50 cm3, a preoperative international prostate symptom score of > 15, a urine flow rate of < 15 ml/min, and urethral andrectal radiation doses of > 210 and > 180 Gy, respectively, tended to have more common radiation reactions. Thus, brachytherapy is a reasonably safe treatment for PC.

  20. ANALYSIS OF COMPLICATIONS DUE TO INTRATISSUE RADIOTHERAPY USING CONSTANT SOURCES IN PATIENTS WITH PROSTATE CANCER

    Directory of Open Access Journals (Sweden)

    A. V. Petrovsky

    2014-07-01

    Full Text Available Brachytherapy is a standard treatment for localized advanced prostate cancer (PC. Complications due to interstitial radiotherapy using permanent sources were analyzed in 149 patients. The incidence of early grade 3 radiation urethritis was 7.4 % and that of rectitis was 3.4%. Late radiation urethritis and rectitis were recorded in 3.4 and 0.7 %, respectively. Sexual function 12 months later was preserved in 86.6 % of the patients. Studies established no statistically significant factors that influenced the frequency of complications. The patients with a prostate volume of > 50 cm3, a preoperative international prostate symptom score of > 15, a urine flow rate of < 15 ml/min, and urethral andrectal radiation doses of > 210 and > 180 Gy, respectively, tended to have more common radiation reactions. Thus, brachytherapy is a reasonably safe treatment for PC.

  1. Cost-benefit analysis on radiotherapy services for cancer treatment, with LINAC type equipments (linear accelerators

    Directory of Open Access Journals (Sweden)

    Luiz Alberto Blois

    2014-12-01

    Full Text Available This work consists in analyzing the economic feasibility of the investment to implement a Radiotherapy sector for radiological of cancer treatment by type linear accelerators equipments, based on the case of a public hospital in São Paulo. From technical and financial details of the project and the survey reference values for health care to their procedures, the statistical outcome of treatment on patients' life expectancy and average income indicators of the state's population, were estimated to income (private and social and expenses of this health service and other elements that make up the flow of the investment project box. From these estimates we evaluated public and private investment return, ie, if it fits only on the public sector or if private sector could also implement this projects geared exclusively to free admittance.

  2. Analysis of late complications after rapid hyperfractionated radiotherapy in advanced head and neck cancers

    International Nuclear Information System (INIS)

    Nguyen, T.D.; Panis, X.; Froissart, D.; Legros, M.; Coninx, P.; Loirette, M.

    1988-01-01

    Late effects were analyzed in a series of 39 patients with a 2-year minimal follow-up who were treated by rapid hyperfractionated radiotherapy. The total dose was 66-72 Gy delivered in two series of 33-36 Gy separated by a 2-4 week rest interval. The number of daily fractions ranged from 8 to 6 and the interval between each fraction was 2 hr. Late complications consisted of cervical fibrosis, mucosal necrosis, bone necrosis, trismus, and laryngeal edema. Seventy percent of patients experienced late complications, and in 54% of cases, these reactions were considered severe, causing death in 13% of patients. No relationship was found between field sizes, dosimetric data and type and frequency of late effects. It is therefore suggested that the interval between two daily sessions in any multifractionated protocol may be of critical importance

  3. Prognostic analysis of uterine cervical cancer treated with postoperative radiotherapy: importance of positive or close parametrial resection margin

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yi Jun; Lee, Kyung Ja; Park, Kyung Ran [Dept. of Radiation Oncology, (Korea, Republic of); and others

    2015-06-15

    To analyze prognostic factors for locoregional recurrence (LRR), distant metastasis (DM), and overall survival (OS) in cervical cancer patients who underwent radical hysterectomy followed by postoperative radiotherapy (PORT) in a single institute. Clinicopathologic data of 135 patients with clinical stage IA2 to IIA2 cervical cancer treated with PORT from 2001 to 2012 were reviewed, retrospectively. Postoperative parametrial resection margin (PRM) and vaginal resection margin (VRM) were investigated separately. The median treatment dosage of external beam radiotherapy (EBRT) to the whole pelvis was 50.4 Gy in 1.8 Gy/fraction. High-dose-rate vaginal brachytherapy after EBRT was given to patients with positive or close VRMs. Concurrent platinum-based chemoradiotherapy (CCRT) was administered to 73 patients with positive resection margin, lymph node (LN) metastasis, or direct extension of parametrium. Kaplan-Meier method and log-rank test were used for analyzing LRR, DM, and OS; Cox regression was applied to analyze prognostic factors. The 5-year disease-free survival was 79% and 5-year OS was 91%. In univariate analysis, positive or close PRM, LN metastasis, direct extension of parametrium, lymphovascular invasion, histology of adenocarcinoma, and chemotherapy were related with more DM and poor OS. In multivariate analysis, PRM and LN metastasis remained independent prognostic factors for OS. PORT after radical hysterectomy in uterine cervical cancer showed excellent OS in this study. Positive or close PRM after radical hysterectomy in uterine cervical cancer correlates with poor prognosis even with CCRT. Therefore, additional treatments to improve local control such as radiation boosting need to be considered.

  4. Partial Breast Irradiation Versus Whole Breast Radiotherapy for Early-Stage Breast Cancer: A Decision Analysis

    International Nuclear Information System (INIS)

    Sher, David J.; Wittenberg, Eve; Taghian, Alphonse G.; Bellon, Jennifer R.; Punglia, Rinaa S.

    2008-01-01

    Purpose: To compare the quality-adjusted life expectancy between women treated with partial breast irradiation (PBI) vs. whole breast radiotherapy (WBRT) for estrogen receptor-positive early-stage breast cancer. Methods and Materials: We developed a Markov model to describe health states in the 15 years after radiotherapy for estrogen receptor-positive early-stage breast cancer. Breast cancer recurrences were separated into local recurrences and elsewhere failures. Ipsilateral breast tumor recurrence (IBTR) risk was extracted from the Oxford overview, and rates and utilities were adapted from the literature. We studied two cohorts of women (aged 40 and 55 years), both of whom received adjuvant tamoxifen. Results: Assuming a no evidence of disease (NED)-PBI utility of 0.93, quality-adusted life expectancy after PBI (and WBRT) was 12.61 (12.57) and 12.10 (12.06) years for 40-year-old and 55-year-old women, respectively. The NED-PBI utility thresholds for preferring PBI over WBRT were 0.923 and 0.921 for 40-year-old and 55-year-old women, respectively, both slightly greater than the NED-WBRT utility. Outcomes were sensitive to the utility of NED-PBI, the PBI hazard ratio for local recurrence, the baseline IBTR risk, and the percentage of IBTRs that were local. Overall the degree of superiority of PBI over WBRT was greater for 55-year-old women than for 40-year-old women. Conclusions: For most utility values of the NED-PBI health state, PBI was the preferred treatment modality. This result was highly sensitive to patient preferences and was also dependent on patient age, PBI efficacy, IBTR risk, and the fraction of IBTRs that were local

  5. Radiotherapy for vertebral metastases. Analysis of symptoms and clinical effects by MR imaging

    International Nuclear Information System (INIS)

    Sugiyama, Akira

    1994-01-01

    Fifty patients with 63 symptomatic vertebral metastasis (18 sites: pain only, 28 sites: radiculopathy with pain, 17 sites: myelopathy) were treated by radiotherapy. Primary lesions were located in the lung (9 cases), breast (9), colorectal area (9), prostate (7) and so on. We correlated the radiologic findings, symptoms and clinical effects with metastatic features which were classified into 4 types by MR imaging: non-deformity, expanding, vertebral collapse, and destructive mass. Each type of metastasis was accompanied with or without epidural tumor. Osteolytic metastases were apt to create features of deformity (expanding type: 18 vertebrae, vertebral collapse type: 17, destructive mass type: 9). The features of osteoblastic metastases were no deformity (18 vertebrae) and expanding type (2). The symptom of pain only occurred most frequently in the lumbosacral spine. The vertebral body deformity of symptomatic sites was relatively slight (non-deformity type: 6 sites, expanding type: 6, vertebral collapse type: 6), and epidural tumors were seen at only 2 sites. The effect of radiotherapy was excellent (complete pain relief: 64.7%, partial pain relief: 29.4%). Radiculopathy occurred most frequently in the lumber spine. Vertebral body deformity was noted in most symptomatic sites (expanding type: 9 sites, vertebral collapse type: 10, destructive mass type: 2). Complete relief was obtained in 6 sites (22.2%), partial relief in 18 (63.0%). Myelopathy occurred most often in the thoracic spine, followed by the lumbar spine. The vertebral body deformity was severe (expanding: 3 cases, vertebral collapse type: 3, destructive mass type: 6). Epidural tumors were also present in all but one case. Six of 13 patients treated with radiation alone improved. These 6 patients had non-deformity or expanding types with epidural tumor. No improvement was seen in the vertebral collapse type with epidural tumor or destructive mass type. (author)

  6. Analysis of Radiotherapy Associated Factors in Stage IIb Carcinoma of Uterine Cervix

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Chang Woo; Jeung, Tae Sig; Yum, Ha Yong [Kosin Medical College of Medicine, Pusan (Korea, Republic of)

    1990-12-15

    331 patients of stage IIb uterine cervix cancer treated by radiation alone at Kosin Medical Center between June 1980 and Dec. 1985 were analysed to determine parameters of radiotherapy associated to disease states. Survival rate was highest among the reported (82.8% for crude and 82.4% for disease free survival). Pelvic control rate in 6 weeks after the end of radiotherapy was 93.6% in the patients treated with ICR following total pelvic radiation and 71.6% with small field additional external irradiation. 5 year survival rate in those who achieved pelvic control was 98. 9% and 12.9% in those who had pelvic failure and/or metastasis after radiation. The survival rate figured maximal 88.5% with dosage of 7500-8500 cGy to point A with acceptable incidence of complications (4.9%) but without increasing survival above it and minimal 74.1% with dosage of less than 6500 cGy. The treatment failure was counted 18.7% (62 of 331 patients): Local failure 72. 6% ( 45 of 62 patients), locoregional failure 3.2% (2 of 62 patients) and distant failure 24% (15 of 62 patients). Late complications were found In 50 patients (15.1%) and 42% of them was rectal bleeding and stenosis. The dose of 8500 cGy to point A was found to be critical for complication and 70% of complications occurred above it and was more serious one such as fistula. Rectal complications were developed above rectal dose 6500 cGy and bladder complication above bladder dose 7500 cGy. Major cause of death was cachexia due to locoregional failure (73.7% of death), next was due to metastasis to lung, liver and bone, and only 3 patients died of complication of intestinal perforations and obstruction. In conclusion higher external radiation dose for a bulky uterine cervix and barrel shaped uterus was essential for local control.

  7. Analysis of Radiotherapy Associated Factors in Stage IIb Carcinoma of Uterine Cervix

    International Nuclear Information System (INIS)

    Moon, Chang Woo; Jeung, Tae Sig; Yum, Ha Yong

    1990-01-01

    331 patients of stage IIb uterine cervix cancer treated by radiation alone at Kosin Medical Center between June 1980 and Dec. 1985 were analysed to determine parameters of radiotherapy associated to disease states. Survival rate was highest among the reported (82.8% for crude and 82.4% for disease free survival). Pelvic control rate in 6 weeks after the end of radiotherapy was 93.6% in the patients treated with ICR following total pelvic radiation and 71.6% with small field additional external irradiation. 5 year survival rate in those who achieved pelvic control was 98. 9% and 12.9% in those who had pelvic failure and/or metastasis after radiation. The survival rate figured maximal 88.5% with dosage of 7500-8500 cGy to point A with acceptable incidence of complications (4.9%) but without increasing survival above it and minimal 74.1% with dosage of less than 6500 cGy. The treatment failure was counted 18.7% (62 of 331 patients): Local failure 72. 6% ( 45 of 62 patients), locoregional failure 3.2% (2 of 62 patients) and distant failure 24% (15 of 62 patients). Late complications were found In 50 patients (15.1%) and 42% of them was rectal bleeding and stenosis. The dose of 8500 cGy to point A was found to be critical for complication and 70% of complications occurred above it and was more serious one such as fistula. Rectal complications were developed above rectal dose 6500 cGy and bladder complication above bladder dose 7500 cGy. Major cause of death was cachexia due to locoregional failure (73.7% of death), next was due to metastasis to lung, liver and bone, and only 3 patients died of complication of intestinal perforations and obstruction. In conclusion higher external radiation dose for a bulky uterine cervix and barrel shaped uterus was essential for local control

  8. Respiratory gating and multi field technique radiotherapy for esophageal cancer

    International Nuclear Information System (INIS)

    Ohta, Atsushi; Kaidu, Motoki; Tanabe, Satoshi

    2017-01-01

    To investigate the effects of a respiratory gating and multi field technique on the dose-volume histogram (DVH) in radiotherapy for esophageal cancer. Twenty patients who underwent four-dimensional computed tomography for esophageal cancer were included. We retrospectively created the four treatment plans for each patient, with or without the respiratory gating and multi field technique: No gating-2-field, No gating-4-field, Gating-2-field, and Gating-4-field plans. We compared the DVH parameters of the lung and heart in the No gating-2-field plan with the other three plans.Result In the comparison of the parameters in the No gating-2-field plan, there are significant differences in the Lung V 5Gy , V 20Gy , mean dose with all three plans and the Heart V 25Gy -V 40Gy with Gating-2-field plan, V 35Gy , V 40Gy , mean dose with No Gating-4-field plan and V 30Gy -V 40Gy , and mean dose with Gating-4-field plan. The lung parameters were smaller in the Gating-2-field plan and larger in the No gating-4-field and Gating-4-field plans. The heart parameters were all larger in the No gating-2-field plan. The lung parameters were reduced by the respiratory gating technique and increased by the multi field technique. The heart parameters were reduced by both techniques. It is important to select the optimal technique according to the risk of complications. (author)

  9. Particle radiotherapy, a novel external radiation therapy, versus liver resection for hepatocellular carcinoma accompanied with inferior vena cava tumor thrombus: A matched-pair analysis.

    Science.gov (United States)

    Komatsu, Shohei; Kido, Masahiro; Asari, Sadaki; Toyama, Hirochika; Ajiki, Tetsuo; Demizu, Yusuke; Terashima, Kazuki; Okimoto, Tomoaki; Sasaki, Ryohei; Fukumoto, Takumi

    2017-12-01

    Hepatocellular carcinoma accompanied with inferior vena cava tumor thrombus carries a dismal prognosis, and the feasibility of local treatment has remained controversial. The present study aimed to compare the outcomes of particle radiotherapy and liver resection in patients with hepatocellular carcinoma with inferior vena cava tumor thrombus. Thirty-one and 19 patients, respectively, underwent particle radiotherapy and liver resection for hepatocellular carcinoma with inferior vena cava tumor thrombus. A matched-pair analysis was undertaken to compare the short- and long-term outcomes according to tumor stage determined using the tumor-node-metastasis classification. Both stages IIIB and IV (IVA and IVB) patients were well-matched for 12 factors, including treatment policy and patient and tumor characteristics. The median survival time of matched patients with stage IIIB tumors in the particle radiotherapy group was greater than that in the liver resection group (748 vs 272 days, P = .029), whereas no significant difference was observed in the median survival times of patients with stage IV tumors (239 vs 311 days, respectively). There were significantly fewer treatment-related complications of grade 3 or greater in the particle radiotherapy group (0%) than in the liver resection group (26%). Particle radiotherapy is potentially preferable in hepatocellular carcinoma patients with stage IIIB inferior vena cava tumor thrombus and at least equal in efficiency to liver resection in those with stage IV disease, while causing significantly fewer complications. Considering the relatively high survival and low invasiveness of particle radiotherapy when compared to liver resection, this approach may represent a novel treatment modality for hepatocellular carcinoma with inferior vena cava tumor thrombus. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. The prognostic value of time parameters in adjuvant radiotherapy of head and neck cancer. A retrospective analysis of 138 patients

    International Nuclear Information System (INIS)

    Dietl, B.; Schaefer, C.; Koelbl, O.

    2005-01-01

    Purpose: to answer the question, how the parameters waiting time, radiation treatment time and overall treatment time (OTT) influenced the endpoints overall (OS), event-free (EFS) and local recurrence-free survival (LRFS) in patients with locally advanced head-and-neck cancer, who had received postoperative radiotherapy. Patients and methods: 138 patients were included into a retrospective analysis from 10/1993 to 05/2000. Besides the time parameters waiting time, radiation treatment time and OTT, tumor- and therapy-related parameters (T-, N-, R-status, grading, tumor site, surgical technique, and postoperative hemoglobin < 12 g/dl) with potential impact on the endpoints were investigated in the univariate analysis (Kaplan-Meier log-rank test). Individual parameters with a significant impact (p = 0.05) were subjected to a multivariate Cox regression analysis. Results: besides a postoperative hemoglobin value < 12 g/dl, in the univariate analysis an OTT ≥ 105 days negatively influenced all endpoints, as well as a radiation treatment time ≥ 60 days. On multivariate Cox regression analysis, postoperative hemoglobin < 12 g/dl and an OTT ≥ 105 days were identified as independent negative prognostic factors for all endpoints. Conclusion: the waiting time should be managed according to the ASARA (as short as reasonably achievable) recommendation, radiation treatment should not be protracted exceeding an overall treatment of 105 days. Generally, time parameters should be routinely included in the standard tumor documentation, thus facilitating further evaluation of these prognostically relevant factors. (orig.)

  11. Analysis of a large number of clinical studies for breast cancer radiotherapy: estimation of radiobiological parameters for treatment planning

    International Nuclear Information System (INIS)

    Guerrero, M; Li, X Allen

    2003-01-01

    Numerous studies of early-stage breast cancer treated with breast conserving surgery (BCS) and radiotherapy (RT) have been published in recent years. Both external beam radiotherapy (EBRT) and/or brachytherapy (BT) with different fractionation schemes are currently used. The present RT practice is largely based on empirical experience and it lacks a reliable modelling tool to compare different RT modalities or to design new treatment strategies. The purpose of this work is to derive a plausible set of radiobiological parameters that can be used for RT treatment planning. The derivation is based on existing clinical data and is consistent with the analysis of a large number of published clinical studies on early-stage breast cancer. A large number of published clinical studies on the treatment of early breast cancer with BCS plus RT (including whole breast EBRT with or without a boost to the tumour bed, whole breast EBRT alone, brachytherapy alone) and RT alone are compiled and analysed. The linear quadratic (LQ) model is used in the analysis. Three of these clinical studies are selected to derive a plausible set of LQ parameters. The potential doubling time is set a priori in the derivation according to in vitro measurements from the literature. The impact of considering lower or higher T pot is investigated. The effects of inhomogeneous dose distributions are considered using clinically representative dose volume histograms. The derived LQ parameters are used to compare a large number of clinical studies using different regimes (e.g., RT modality and/or different fractionation schemes with different prescribed dose) in order to validate their applicability. The values of the equivalent uniform dose (EUD) and biologically effective dose (BED) are used as a common metric to compare the biological effectiveness of each treatment regime. We have obtained a plausible set of radiobiological parameters for breast cancer. This set of parameters is consistent with in vitro

  12. Hormone therapy and radiotherapy for early prostate cancer: A utility-adjusted number needed to treat (NNT) analysis

    International Nuclear Information System (INIS)

    Jani, Ashesh B.; Kao, Johnny; Heimann, Ruth; Hellman, Samuel

    2005-01-01

    Purpose: To quantify, using the number needed to treat (NNT) methodology, the benefit of short-term (≤6 months) hormone therapy adjuvant to radiotherapy in the group of patients with early (clinical stage T1-T2c) prostate cancer. Methods and materials: The absolute biochemical control benefit for the use of hormones adjuvant to radiotherapy in early-stage disease was determined by literature review. A model was developed to estimate the utility-adjusted survival detriment due to the side effects of hormone therapy. The NNTs before and after the incorporation of hormone sequelae were computed; the sign and magnitude of the NNTs were used to gauge the effect of the hormones. Results: The absolute NNT analysis, based on summarizing the results of 8 reports including a total of 3652 patients, demonstrated an advantage to the addition of hormones for the general early-stage prostate cancer population as well as for all prognostic groups. After adjustment for hormone-induced functional loss, the advantage of hormones remained considerable in the high- and intermediate-risk groups, with the utility-adjusted NNT becoming weakened in the low-risk group when the utility compromise from complications of hormones was assumed to be considerable. Conclusions: Short-term hormone therapy seems to be beneficial for selected early-stage prostate cancer patients. The advantage seems to be greatest in the intermediate- and high-risk groups; with current follow-up, the side effects of hormones may outweigh their benefit in certain clinical situations in the favorable group. The present investigation demonstrates the significant role of the NNT technique for oncologic and radiotherapeutic management decisions when treatment complications need to be considered and balanced with the beneficial effects of the treatment

  13. Clinicopathologic Analysis of Microscopic Extension in Lung Adenocarcinoma: Defining Clinical Target Volume for Radiotherapy

    International Nuclear Information System (INIS)

    Grills, Inga S.; Fitch, Dwight L.; Goldstein, Neal S.; Yan Di; Chmielewski, Gary W.; Welsh, Robert J.; Kestin, Larry L.

    2007-01-01

    Purpose: To determine the gross tumor volume (GTV) to clinical target volume margin for non-small-cell lung cancer treatment planning. Methods: A total of 35 patients with Stage T1N0 adenocarcinoma underwent wedge resection plus immediate lobectomy. The gross tumor size and microscopic extension distance beyond the gross tumor were measured. The nuclear grade and percentage of bronchoalveolar features were analyzed for association with microscopic extension. The gross tumor dimensions were measured on a computed tomography (CT) scan (lung and mediastinal windows) and compared with the pathologic dimensions. The potential coverage of microscopic extension for two different lung stereotactic radiotherapy regimens was evaluated. Results: The mean microscopic extension distance beyond the gross tumor was 7.2 mm and varied according to grade (10.1, 7.0, and 3.5 mm for Grade 1 to 3, respectively, p < 0.01). The 90th percentile for microscopic extension was 12.0 mm (13.0, 9.7, and 4.4 mm for Grade 1 to 3, respectively). The CT lung windows correlated better with the pathologic size than did the mediastinal windows (gross pathologic size overestimated by a mean of 5.8 mm; composite size [gross plus microscopic extension] underestimated by a mean of 1.2 mm). For a GTV contoured on the CT lung windows, the margin required to cover microscopic extension for 90% of the cases would be 9 mm (9, 7, and 4 mm for Grade 1 to 3, respectively). The potential microscopic extension dosimetric coverage (55 Gy) varied substantially between the stereotactic radiotherapy schedules. Conclusion: For lung adenocarcinomas, the GTV should be contoured using CT lung windows. Although a GTV based on the CT lung windows would underestimate the gross tumor size plus microscopic extension by only 1.2 mm for the average case, the clinical target volume expansion required to cover the microscopic extension in 90% of cases could be as large as 9 mm, although considerably smaller for high-grade tumors

  14. Patterns of care and course of symptoms in palliative radiotherapy. A multicenter pilot study analysis

    International Nuclear Information System (INIS)

    Oorschot, Birgitt van; Geinitz, Hans

    2011-01-01

    To evaluate patterns of care as well as effectiveness and side effects of palliative treatment in four German radiation oncology departments. All referrals in four German radiation oncology departments (two university hospitals, one academic hospital, one private practice) were prospective documented for 1 month in 2008 (2 months at one of the university hospitals). In palliatively irradiated patients, treatment aims and indications as well as treated sites and fractionation schedules were recorded. In addition, symptoms and side effects were analyzed with standardized questionnaires before and at the end of radiotherapy. During the observation period, 603 patients underwent radiation therapy in the four centers and 153 (24%, study popu-lation) were treated with palliative intent. Within the study, patients were most frequently treated for bone (34%) or brain (27%) metastases. 62 patients reported severe or very severe pain, 12 patients reported severe or very severe dyspnea, 27 patients reported neurological deficits or signs of cranial pressure, and 43 patients reported a poor or very poor sense of well-being. The most frequent goals were symptom relief (53%) or prevention of symptoms (46%). Life prolongation was intended in 37% of cases. A wide range of fractionation schedules was applied with total doses ranging from 3-61.2 Gy. Of the patients, 73% received a slightly hypofractionated treatment schedule with doses of > 2.0 Gy to ? 3.0 Gy per fraction and 12% received moderate to highly hypofractionated therapy with doses of > 3.0 Gy to 8.0 Gy. Radiation therapy led to a significant improvement of well-being (35% of patients) and reduction of symptoms, especially with regard to pain (66%), dyspnea (61%), and neurological deficits (60%). Therapy was very well tolerated with only 4.5% grade I or II acute toxicities being observed. Unscheduled termination was observed in 19 patients (12%). Palliative radiation therapy is effective in reducing symptoms, increases

  15. External and intraoperative radiotherapy for resectable and unresectable pancreatic cancer: analysis of survival rates and complications

    International Nuclear Information System (INIS)

    Nishimura, Yasumasa; Hosotani, Ryo; Shibamoto, Yuta; Kokubo, Masaki; Kanamori, Shuichi; Sasai, Keisuke; Hiraoka, Masahiro; Ohshio, Gakuji; Imamura, Masayuki; Takahashi, Masaji; Abe, Mitsuyuki

    1997-01-01

    Purpose: Clinical results of intraoperative radiotherapy (IORT) and/or external beam radiotherapy (EBRT) for both resectable and unresectable pancreatic cancer were analyzed. Methods and Materials: Between 1980 and 1995, 332 patients with pancreatic cancer were treated with surgery and/or radiation therapy (RT). Of the 332 patients, 157 patients were treated with surgical resection of pancreatic tumor, and the remaining 175 patients had unresectable pancreatic tumors. Among the 157 patients with resected pancreatic cancer, 62 patients were not treated with RT, while 40 patients were treated with EBRT alone (mean RT dose; 46.3 Gy) and 55 patients with IORT (25.2 Gy) ± EBRT (44.0 Gy). On the other hand, among the 175 patients with unresectable pancreatic cancer, 58 patients were not treated with RT, 46 patients were treated with EBRT alone (39.2 Gy), and the remaining 71 patients with IORT (29.3 Gy) ± EBRT (41.2 Gy). Results: For 87 patients with curative resection, the median survival times (MSTs) of the no-RT, the EBRT, and the IORT ± EBRT groups were 10.4, 13.0, and 15.5 months, respectively, without significant difference. For 70 patients with non curative resection, the MSTs of the no-RT, the EBRT, and the IORT ± EBRT groups were 5.3, 8.7, and 6.5 months, respectively. When the EBRT and the IORT ± EBRT groups were combined, the survival rate was significantly higher than that of the no RT group for non curatively resected pancreatic cancers (log rank test; p = 0.028). The 2-year survival probability of the IORT ± EBRT group (16%) was higher than that of the EBRT group (0%). For unresectable pancreatic cancer, the MSTs of 52 patients without distant metastases were 6.7 months for palliative surgery alone, 7.6 months for EBRT alone, and 8.2 months for IORT ± EBRT. The survival curve of the IORT ± EBRT group was significantly better than that of the no-RT group (p 2 years) were obtained by IORT ± EBRT for non curatively resected and unresectable pancreatic

  16. Patterns of care and course of symptoms in palliative radiotherapy. A multicenter pilot study analysis

    Energy Technology Data Exchange (ETDEWEB)

    Oorschot, Birgitt van [Wuerzburg Univ. (Germany). Dept. of Radiation Oncology; Schuler, Michael [Wuerzburg Univ. (Germany). Inst. of Psychotherapy and Medical Psychology; Simon, Anke [HELIOS Klinikum Erfurt (Germany). Dept. of Radiation Oncology; Schleicher, Ursula [Center for Radiotherapy, Dueren (Germany); Geinitz, Hans [Technische Univ. Muenchen (Germany). Dept. of Radiotherapy and Radiooncology

    2011-08-15

    To evaluate patterns of care as well as effectiveness and side effects of palliative treatment in four German radiation oncology departments. All referrals in four German radiation oncology departments (two university hospitals, one academic hospital, one private practice) were prospective documented for 1 month in 2008 (2 months at one of the university hospitals). In palliatively irradiated patients, treatment aims and indications as well as treated sites and fractionation schedules were recorded. In addition, symptoms and side effects were analyzed with standardized questionnaires before and at the end of radiotherapy. During the observation period, 603 patients underwent radiation therapy in the four centers and 153 (24%, study popu-lation) were treated with palliative intent. Within the study, patients were most frequently treated for bone (34%) or brain (27%) metastases. 62 patients reported severe or very severe pain, 12 patients reported severe or very severe dyspnea, 27 patients reported neurological deficits or signs of cranial pressure, and 43 patients reported a poor or very poor sense of well-being. The most frequent goals were symptom relief (53%) or prevention of symptoms (46%). Life prolongation was intended in 37% of cases. A wide range of fractionation schedules was applied with total doses ranging from 3-61.2 Gy. Of the patients, 73% received a slightly hypofractionated treatment schedule with doses of > 2.0 Gy to ? 3.0 Gy per fraction and 12% received moderate to highly hypofractionated therapy with doses of > 3.0 Gy to 8.0 Gy. Radiation therapy led to a significant improvement of well-being (35% of patients) and reduction of symptoms, especially with regard to pain (66%), dyspnea (61%), and neurological deficits (60%). Therapy was very well tolerated with only 4.5% grade I or II acute toxicities being observed. Unscheduled termination was observed in 19 patients (12%). Palliative radiation therapy is effective in reducing symptoms, increases

  17. Evaluating quality of life and cost implications of prophylactic radiotherapy in mesothelioma: Health economic analysis of the SMART trial.

    Directory of Open Access Journals (Sweden)

    Samuel Alan Stewart

    Full Text Available The SMART trial is a UK-based, multicentre RCT comparing prophylactic radiotherapy and symptom-based (deferred radiotherapy in 203 patients with Malignant Pleural Mesothelioma who had undergone large bore pleural interventions. Using costs and quality of life data collected alongside the clinical trial, we will estimate the cost-effectiveness of prophylactic radiotherapy compared to deferred radiotherapy over a 1-year period.Healthcare utilization and costs were captured during the trial. Utility weights produced by the EQ-5D questionnaire were used to determine quality-adjusted life-years (QALY gained. The incremental cost-effectiveness ratio was calculated over the one-year trial period.Costs were similar in the immediate and deferred radiotherapy groups: £5480.40 (SD = £7040; n = 102 and £5461.40 (SD = £7770; n = 101 respectively. There was also no difference in QALY: 0.498 (95% CI: [0.45, 0.547] in the prophylactic radiotherapy group versus 0.525 (95% CI: [0.471, 0.580] in the deferred group. At a willingness to pay threshold of £30,000/QALY there was only a 24% chance that prophylactic radiotherapy was cost-effective compared to deferred radiotherapy.There was no significant effect of prophylactic radiotherapy on quality of life in the intervention group, nor was there any discernable decrease in healthcare costs. There is little evidence to suggest that prophylactic radiotherapy is a cost-effective intervention in this population.ISRCTN72767336 with ISRCTN.

  18. Primary radiotherapy or postoperative radiotherapy in patients with head and neck cancer. Comparative analysis of inflammation-based prognostic scoring systems

    International Nuclear Information System (INIS)

    Selzer, Edgar; Grah, Anja; Heiduschka, Gregor; Thurnher, Dietmar; Kornek, Gabriela

    2015-01-01

    Inflammation-based scoring systems have potential value in evaluating the prognosis of cancer patients; however, detailed comparative analyses in well-characterized head and neck cancer patient collectives are missing. We analyzed overall survival (OS) in locally advanced head and neck cancer patients who were treated with curative intent by primary radiotherapy (RT) alone, by RT in combination with cetuximab (RIT) or with cisplatin (RCHT), and by primary surgery followed by postoperative radiotherapy (PORT). The primary RT collective (N = 170) was analyzed separately from the surgery plus RT group (N = 148). OS was estimated using the Kaplan-Meyer method. Cox proportional-hazard regression models were applied to compare the risk of death among patients stratified according to risk factors and the inflammation-based Glasgow Prognostic Score (GPS), the modified GPS (mGPS), the neutrophil-lymphocyte ratio (NLR), the platelet-lymphocyte ratio (PLR), and the prognostic index (PI). A prognostic relevance of the scoring systems for OS was observed in the primarily irradiated, but not in the PORT collective. OS was 35.5, 18.8, and 15.4 months, respectively, according to GPS 0, 1, and 2. OS according to mGPS 0-2 was identical. The PLR scoring system was not of prognostic relevance, while OS was 27.3 months in the NLR 0 group and 17.3 months in the NLR 1 group. OS was 35.5 months in PI 0, 16.1 months in PI 1, and 22.6 months in PI 2. GPS/mGPS scoring systems are able to discriminate between three risk groups in primarily, but not postoperatively irradiated locally advanced head and neck cancer patients. (orig.) [de

  19. Radiobiological analysis of the field in field technique in breast cancer radiotherapy treatments

    Energy Technology Data Exchange (ETDEWEB)

    Medel B, E.; Vasquez R, M. A. [IMSS, Centro Medico Nacional Manuel Avila Camacho, Calle 2 Nte. 2004, Barrio de San Francisco, 72090 Puebla, Pue. (Mexico); Tejeda M, G., E-mail: marcosalivasquez@gmail.com [Benemerita Universidad Autonoma de Puebla, Facultad de Ciencias Fisico Matematicas, Av. San Claudio y 18 Sur, Ciudad Universitaria, 72570 Puebla, Pue. (Mexico)

    2015-10-15

    Full text: In vivo dosimetry was performed in 6 unilateral breast cancer patients treated with external beam radiation therapy in order to evaluate the dose calculated by the radiotherapy treatment planning system (Xi O, ELEKTA). Results show a maximum difference of 0.473 Gy between the dose calculated by the treatment planning system and the dose measured in vivo using solid state detectors. Based on the DVHs statistics, tumor control probability (Tcp) was obtained using the Target-Poisson model, with the following Tcp parameters: α=0.288/Gy, α{sub s}pread= 0.13 and α/β=4.9 Gy. Tcp average obtained for the Clinical Tumor Volume (Ctv) is 35.1% and for Supra Clavicle Volume (Scv) is 35.345%. Finally using Lyman model Normal Tissue Complication Probability (Ntcp) was obtained for the following endpoints: contralateral breast fibrosis, lung radiation pneumonitis and heart pericarditis. Nonetheless the Ntcp values are not high; the improvement of the Tcp based on this plan makes Ntcp for lung radiation pneumonitis reach the 100% of probability in some cases. (Author)

  20. Stereotactic Body Radiotherapy for Metastatic Lung Cancer as Oligo-Recurrence: An Analysis of 42 Cases

    Directory of Open Access Journals (Sweden)

    Wataru Takahashi

    2012-01-01

    Full Text Available Purpose. To investigate the outcome and toxicity of stereotactic body radiotherapy (SBRT in patients with oligo-recurrence cancer in the lung (ORCL. Methods and Materials. A retrospective review of 42 patients with ORCL who underwent SBRT in our two hospitals was conducted. We evaluated the outcome and adverse effects after SBRT for ORCL. Results. All patients finished their SBRT course without interruptions of toxicity reasons. The median follow-up period was 20 months (range, 1–90 months. The 2-year local control rate and overall survival were 87% (95% CI, 75–99% and 65% (95% CI, 48–82%. As for prognostic factor, the OS of patients with a short disease-free interval (DFI months, between the initial therapy and SBRT for ORCL, was significantly worse than the OS of long DFI months (. The most commonly observed late effect was radiation pneumonitis. One patient had grade 4 gastrointestinal toxicity (perforation of gastric tube. No other ≧ grade 3 acute and late adverse events occurred. There were no treatment-related deaths during this study. Conclusions. In patients with ORCL, radical treatment with SBRT is safe and provides a chance for long-term survival by offering favorable local control.

  1. Measurement and analysis of the thoracic patient setup deviations in routine radiotherapy

    International Nuclear Information System (INIS)

    Jia Mingxuan; Zou Huawei; Wu Rong; Sun Jian; Dong Xiaoqi

    2003-01-01

    Objective: To determine the magnitude of the setup deviations of the thoracic patients in routine radiotherapy. Methods: Altogether 408 films for 21 thoracic patients were recorded using the electronic portal imaging device (EPID), and comparison with reference CT simulator digitally-reconstructed radiograph (DRR) for anterior-posterior fields was performed. The deviation of setup for 21 patients in the left-right (RL), superior-inferior (SI) directions and rotation about the anterior-posterior (AP) axis were measured and analyzed. Results: Without immobilization device, the mean translational and rotational setup deviations were (0.7±3.1) mm and (1.5±4.1) mm in the RL and SI directions, respectively, and (0.3±2.4) degree about AP axis. With immobilization device, the mean translational and rotational setup deviations were (0.5±2.4) mm and (0.8±2.7) mm in the RL and SI directions respectively, and (0.2±1.6) degree about AP axis. Conclusion: The setup deviations in thoracic patients irradiation may be reduced with the use of the immobilization device. The setup deviation in the SI direction is greater than that in the RL direction. The setup deviations are mainly random errors

  2. Quality indicators in radiotherapy

    International Nuclear Information System (INIS)

    Cionini, Luca; Gardani, Gianstefano; Gabriele, Pietro; Magri, Secondo; Morosini, Pier Luigi; Rosi, Antonella; Viti, Vincenza

    2007-01-01

    Background and purpose: There is a widespread and increasing tendency to develop hospital performance indicators in the field of accreditation/certification systems and quality benchmarking. A study has been undertaken to develop a set of performance indicators for a typical radiotherapy Centre and to evaluate their ability to provide a continuous quality improvement. Materials and methods: A working group consisting of radiation oncologists, medical physicists and radiation technologists under the coordination of experts in health technology assessment has elaborated a set of general indicators able to monitor performances and the quality level of a typical radiotherapy Centre. The work has been carried out through four steps: a preliminary set of indicators was selected; data on these indicators were collected in a number of Italian radiotherapy Centres and medical physics Services; problems in collection and analysis of data were discussed; a final set of indicators was developed. Results: A final set of 13 indicators is here presented. They concern general structural and/or operational features, health physics activities and accuracy and technical complexity of the treatment. Conclusions: The indicators tested in a few Italian Centres of radiotherapy and medical physics Services are now ready to be utilized by a larger community

  3. Individual patient data meta-analysis shows no association between the SNP rs1800469 in TGFB and late radiotherapy toxicity

    International Nuclear Information System (INIS)

    Barnett, Gillian C.; Elliott, Rebecca M.; Alsner, Jan; Andreassen, Christian N.; Abdelhay, Osama; Burnet, Neil G.; Chang-Claude, Jenny; Coles, Charlotte E.; Gutiérrez-Enríquez, Sara; Fuentes-Raspall, Maria J.; Alonso-Muñoz, Maria C.; Kerns, Sarah; Raabe, Annette; Symonds, R. Paul; Seibold, Petra; Talbot, Chris J.; Wenz, Frederik; Wilkinson, Jennifer; Yarnold, John; Dunning, Alison M.

    2012-01-01

    Background and purpose: Reported associations between risk of radiation-induced normal tissue injury and single nucleotide polymorphisms (SNPs) in TGFB1, encoding the pro-fibrotic cytokine transforming growth factor-beta 1 (TGF-β1), remain controversial. To overcome publication bias, the international Radiogenomics Consortium collected and analysed individual patient level data from both published and unpublished studies. Materials and methods: TGFB1 SNP rs1800469 c.-1347T>C (previously known as C-509T) genotype, treatment-related data, and clinically-assessed fibrosis (measured at least 2 years after therapy) were available in 2782 participants from 11 cohorts. All received adjuvant breast radiotherapy. Associations between late fibrosis or overall toxicity, reported by STAT (Standardised Total Average Toxicity) score, and rs1800469 genotype were assessed. Results: No statistically significant associations between either fibrosis or overall toxicity and rs1800469 genotype were observed with univariate or multivariate regression analysis. The multivariate odds ratio (OR), obtained from meta-analysis, for an increase in late fibrosis grade with each additional rare allele of rs1800469 was 0.98 (95% Confidence Interval (CI) 0.85–1.11). This CI is sufficiently narrow to rule out any clinically relevant effect on toxicity risk in carriers vs. non-carriers with a high probability. Conclusion: This meta-analysis has not confirmed previous reports of association between fibrosis or overall toxicity and rs1800469 genotype in breast cancer patients. It has demonstrated successful collaboration within the Radiogenomics Consortium.

  4. The value of radiotherapy in breast cancer patients with isolated ipsilateral supraclavicular lymph node metastasis without distant metastases at diagnosis: a retrospective analysis of Chinese patients

    Directory of Open Access Journals (Sweden)

    Wu SG

    2014-02-01

    Full Text Available San-Gang Wu,1,* Jia-Yuan Sun,2,* Juan Zhou,3,* Feng-Yan Li,2 Qin Lin,1 Huan-Xin Lin,2 Zhen-Yu He2 1Xiamen Cancer Center, Department of Radiation Oncology, the First Affiliated Hospital of Xiamen University, Xiamen, People's Republic of China; 2Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Department of Radiation Oncology, Collaborative Innovation Center of Cancer Medicine, Guangzhou, People’s Republic of China; 3Xiamen Cancer Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Xiamen University, Xiamen, People's Republic of China *These authors contributed equally to this work Background: The purpose of this study was to investigate the prognosis of ipsilateral supraclavicular lymph node metastasis (ISLM without evidence of distant metastases at diagnosis in Chinese women with breast cancer and to elucidate the clinical value of adjuvant radiotherapy. Methods: We performed a retrospective analysis of clinical data for 39 patients with ISLM from breast cancer without distant metastasis at diagnosis. Combined modality therapy, consisting of neoadjuvant chemotherapy, surgery, and adjuvant chemotherapy with or without adjuvant radiotherapy, was offered to the patients. Results: The patients in this study accounted for 1% of all breast cancer patients treated during the same time period. The median follow-up was 35 months. The 5-year locoregional recurrence-free survival, distant metastasis-free survival, disease-free survival (DFS, and overall survival (OS were 57.3%, 42.3%, 34.4%, and 46.2%, respectively. Twenty-three patients received postoperative adjuvant radiotherapy. However, there was no significant difference in the 3- and 5-year locoregional recurrence-free survival (P=0.693, ISLM-free recurrence (P=0.964, distant metastasis-free survival (P=0.964, DFS (P=0.234, and OS (P=0.329 rates between the groups of patients who received or did not receive adjuvant radiotherapy

  5. Interstitial radiotherapy

    International Nuclear Information System (INIS)

    Scardino, P.T.; Bretas, F.

    1987-01-01

    The authors now have 20 years of experience with modern techniques of brachytherapy. The large number of patients treated in medical centers around the world and the widespread use of this type of radiotherapy have provided us with substantial information about the indications and contraindications, advantages and disadvantages, pitfalls and complications, as well as the results of these techniques. Although the focus of this review is the experience at Baylor using the combined technique of gold seed implantation plus external beam irradiation, the alternative forms of brachytherapy will be described and compared. The authors' intention is to provide the busy clinician with a succinct and informative review indicating the status of modern interstitial radiotherapy and describing day-to-day approach and results

  6. Palliative Radiotherapy

    International Nuclear Information System (INIS)

    Salinas, J.

    2003-01-01

    Palliative care does not attempt to prolong survival but to the achieve the highest quality of life both for the patient and their family covering their physical, psychological, social and spiritual needs. Radiotherapy (RT), one of the most important therapeutic modalities, has a great significance in palliative medicine for cancer since it attempts to reduce as much as possible the acute reaction associated with the treatment for the patient. (Author)

  7. Texture analysis of automatic graph cuts segmentations for detection of lung cancer recurrence after stereotactic radiotherapy

    Science.gov (United States)

    Mattonen, Sarah A.; Palma, David A.; Haasbeek, Cornelis J. A.; Senan, Suresh; Ward, Aaron D.

    2015-03-01

    Stereotactic ablative radiotherapy (SABR) is a treatment for early-stage lung cancer with local control rates comparable to surgery. After SABR, benign radiation induced lung injury (RILI) results in tumour-mimicking changes on computed tomography (CT) imaging. Distinguishing recurrence from RILI is a critical clinical decision determining the need for potentially life-saving salvage therapies whose high risks in this population dictate their use only for true recurrences. Current approaches do not reliably detect recurrence within a year post-SABR. We measured the detection accuracy of texture features within automatically determined regions of interest, with the only operator input being the single line segment measuring tumour diameter, normally taken during the clinical workflow. Our leave-one-out cross validation on images taken 2-5 months post-SABR showed robustness of the entropy measure, with classification error of 26% and area under the receiver operating characteristic curve (AUC) of 0.77 using automatic segmentation; the results using manual segmentation were 24% and 0.75, respectively. AUCs for this feature increased to 0.82 and 0.93 at 8-14 months and 14-20 months post SABR, respectively, suggesting even better performance nearer to the date of clinical diagnosis of recurrence; thus this system could also be used to support and reinforce the physician's decision at that time. Based on our ongoing validation of this automatic approach on a larger sample, we aim to develop a computer-aided diagnosis system which will support the physician's decision to apply timely salvage therapies and prevent patients with RILI from undergoing invasive and risky procedures.

  8. An analysis of an immunological effect in the cases of osteogenic sarcoma treated with massive radiotherapy

    International Nuclear Information System (INIS)

    Fukushima, Hiroshi; Itami, Yasuto; Akamatsu, Noriya; Matsuura, Koichi; Aoki, Haruhito

    1978-01-01

    Changes in immunological competence of 16 patients with osteogenic sarcoma treated with long-term radiotherapy with massive doses were investigated. The irradiation dose ranged from 7600 to 24200 rad with a mean dose of 13000 rad, and the irradiation term ranged from 7 to 24 weeks. The treatment with linac was performed except one case treated with tele-cobalt. The number of lymphocytes in peripheral blood decreased during the irradiation, but a tendency to recover appeared within about 6 months after discontinuance of the irradiation. The number of T cells showed the same change as that of lymphocytes during and after the irradiation. In cases fairly progressed, decreases of lymphocytes and T cells during the irradiation were small as compared to those in cases poorly progressed. A tendency to recover was marked, in the former cases. The effect of the irradiation on B cells was small in comparison with that on T cells. The difference by prognosis was not recognized. The numbers of lymphocytes and T cells and juvenile rate of lymphocytes by PHA in cases which progressed satisfactory over 3 years showed high values after the finish of the irradiation as compared to those in cases in which the time after the irradiation was short. The prognosis in the PPD negative cases and the cases whose PPD changed to negative was clearly unfavorable in comparison with that in the cases in which PPD was positive before to after the irradiation. The above-mentioned results suggested a relationship between an appearance of metastasis to the lung and changes in immunological competence, and these were interesting findings showing a treatment principle for patients with osteogenic sarcoma and an expectation of prognosis. (Tsunoda, M.)

  9. Intraoperative radiotherapy combined with resection for pancreatic cancer. Analysis of survival rates and prognostic factors

    International Nuclear Information System (INIS)

    Kuga, Hirotaka; Nishihara, Kazuyoshi; Matsunaga, Hiroaki; Suehara, Nobuhiro; Abe, Yuji; Ihara, Takaaki; Iwashita, Toshimitsu; Mitsuyama, Shoshu

    2006-01-01

    The purpose of this study was to evaluate the efficiency of intraoperative radiotherapy (IORT) combined with surgical resection. Subjects were consecutive 69 patients with pancreatic cancer treated with surgery alone (n=31) or surgical resection combined with IORT (n=38) in a 13 year period between 1991 and 2003. We evaluated the effects of IORT against local recurrence of cancer and patients' survival, retrospectively. Furthermore, clinicopathological factors affecting the 5-year survival rate in the two groups were comparatively investigated. The IORT group showed a significantly lower local recurrence rate of cancer than that in the surgery alone group (7.8% and 22.6%, respectively; p<0.05). The 5-year survival probability in the IORT group was significantly higher than that in the surgery alone group (29.9% and 3.4%, respectively; p<0.05). According to the Japanese classification of pancreatic cancer, cancers located in the pancreas body or tail, no local residual cancer post operative procedure (R0), low grade local cancer progression (t1, 2), and low grade intrapancreatic neural invasion (ne0, 1) were significantly better prognostic factors in the IORT group than those in the surgery alone group. There were no significant differences between the both groups in the 5-year survival rate in terms of the sex of the patients, cancer of the pancreas head, histological type, more than R1, the presence of lymph node involvement, ne2-3, and clinical stages. IORT is a useful intraoperative adjuvant therapy for pancreatic cancer, when the curative resection is achieved. Our data have suggested that IORT suppresses the local recurrence of cancer and provides the significant survival benefit for those patients. (author)

  10. Multi-institutional analysis of early squamous cell carcinoma of the hypopharynx treated with radical radiotherapy

    International Nuclear Information System (INIS)

    Nakamura, Katsumasa; Shioyama, Yoshiyuki; Kawashima, Mitsuhiko; Saito, Yoshihiro; Nakamura, Naoki; Nakata, Kensei; Hareyama, Masato; Takada, Takahiro; Karasawa, Kumiko; Watanabe, Toshiichi; Yorozu, Atsunori; Tachibana, Hiroyuki; Suzuki, Gen; Hayabuchi, Naofumi; Toba, Takashi; Yamada, Shogo

    2006-01-01

    Purpose: To analyze the outcomes of patients with early hypopharyngeal cancer treated with radical radiotherapy (RT). Methods and Materials: Ten institutions combined the data from 115 patients with Stage I-II hypopharyngeal squamous cell carcinoma treated with definitive RT between 1990 and 2001. The median patient age was 67 years; 99 patients were men and 16 were women. Of the 115 patients, 39 had Stage I and 76 had Stage II disease. Conventional fractionation was used in 98 patients and twice-daily RT in 17 patients; chemotherapy was combined with RT in 57 patients. The median follow-up period was 47 months. Results: The overall and disease-specific 5-year survival rate for 95 patients without synchronous malignancies was 66.0% and 77.4%, respectively. The 5-year disease-specific survival rate by T stage was 95.8% for patients with T1 disease and 70.1% for patients with T2 disease (p = 0.02). Of the 115 patients, local control with laryngeal voice preservation was achieved in 34 of 39 patients with T1 lesions, including 7 patients successfully salvaged, and in 56 of 76 patients with T2 lesions. Sixty-five patients (56.5%) had synchronous or metachronous cancers. Of the 115 patients, 19 died of hypopharyngeal cancer, 10 died of second primary cancers, and 14 died of other causes during the study and follow-up periods. Conclusions: Patients with early hypopharyngeal cancer tended to have a good prognosis after RT. However, second malignancies had an adverse effect on the overall outcomes of patients with early hypopharyngeal cancer

  11. Surgery or stereotactic body radiotherapy for elderly stage I lung cancer? A propensity score matching analysis.

    Science.gov (United States)

    Miyazaki, Takuro; Yamazaki, Takuya; Nakamura, Daisuke; Sato, Shuntaro; Yamasaki, Naoya; Tsuchiya, Tomoshi; Matsumoto, Keitaro; Kamohara, Ryotaro; Hatachi, Go; Nagayasu, Takeshi

    2017-12-01

    The aim of this study was to compare the outcomes of surgery and stereotactic body radiotherapy (SBRT) for elderly clinical stage I non-small cell lung cancer (NSCLC) patients. Patients ≥80 years of age with clinical stage I NSCLC between August 2008 and December 2014 were treated either surgery or SBRT. Propensity score matching was performed to reduce bias in various clinicopathological factors. Surgery was performed in 57 cases and SBRT in 41 cases. In the surgery group, the operations included 34 lobectomies and 23 sublobar resections. In the SBRT group, 27 cases were given 48 Gy in 4 fractions, and 14 were given 60 Gy in 10 fractions. Similar characteristics were identified in age (82 years), gender (male:female ratio 2:1), tumor size (2.2 cm), carcinoembryonic antigen (3.6 ng/ml), Charlson comorbidity index (1), Glasgow prognostic scale (0), and forced expiratory volume in 1 s (1.7 L) after matching. Before matching, the 5-year overall survival (OS) in surgery (68.3%) was significantly better than that in SBRT (47.4%, p = 0.02), and the 5-year disease-specific survival (DSS) (94.1%, 78.2%, p = 0.17) was not significantly different between the groups. The difference in the 5-year OS became non-significant between the matched pairs (57.0%, 49.1%, p = 0.56). The outcomes of surgery and SBRT for elderly patients with the early stage NSCLC were roughly the same.

  12. Cytoreductive prostate radiotherapy in oligometastatic prostate cancer: a single centre analysis of toxicity and clinical outcome.

    Science.gov (United States)

    Riva, Giulia; Marvaso, Giulia; Augugliaro, Matteo; Zerini, Dario; Fodor, Cristiana; Musi, Gennaro; De Cobelli, Ottavio; Orecchia, Roberto; Jereczek-Fossa, Barbara Alicja

    2017-01-01

    The current standard of care for patients with metastatic prostate cancer (mPCa) at diagnosis is androgen deprivation therapy (ADT) with or without anti-androgen and chemotherapy. The aim of this study was to define the role of a local radiotherapy (RT) treatment in the mPCa setting. We retrospectively reviewed data of patients with PCa and bone oligometastases at diagnosis treated in our institution with ADT followed by cytoreductive prostate-RT with or without RT on metastases. Biochemical and clinical failure (BF, CF), overall survival (OS) and RT-toxicity were assessed. We identified 22 patients treated with ADT and external-beam RT on primary between June 2008 and March 2016. All of them but four were also treated for bone metastases. RT on primary with moderately and extremely hypofractionated regimes started after 10.3 months (3.9-51.7) from ADT. After a median follow-up of 26.4 months (10.3-55.5), 20 patients are alive. Twelve patients showed BF after a median time of 23 months (14.5-104) and CF after a median of 23.6 months (15.3-106.1) from the start of ADT. Three patients became castration resistant, starting a new therapy; median time to castration resistance was 31.03 months (range: 29.9-31.5 months). According to the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer (RTOG/EORTC), only one patient developed acute grade 3 genitourinary toxicity. No late grade >2 adverse events were observed. Prostate RT in oligometastatic patients is safe and offers long-lasting local control. When compared to ADT alone, RT on primary seems to improve biochemical control and long-term survival; however, this hypothesis should be investigated in prospective studies. Further research is warranted.

  13. Lung Density Changes After Stereotactic Radiotherapy: A Quantitative Analysis in 50 Patients

    Energy Technology Data Exchange (ETDEWEB)

    Palma, David A., E-mail: david.palma@uwo.ca [Department of Radiation Oncology, VU University Medical Center, Amsterdam (Netherlands); Soernsen de Koste, John van; Verbakel, Wilko F.A.R. [Department of Radiation Oncology, VU University Medical Center, Amsterdam (Netherlands); Vincent, Andrew [Department of Biometrics, Netherlands Cancer Institute, Amsterdam (Netherlands); Senan, Suresh [Department of Radiation Oncology, VU University Medical Center, Amsterdam (Netherlands)

    2011-11-15

    Purpose: Radiologic lung density changes are observed in more than 50% of patients after stereotactic body radiotherapy (SBRT) for lung cancer. We studied the relationship between SBRT dose and posttreatment computed tomography (CT) density changes, a surrogate for lung injury. Methods and Materials: The SBRT fractionation schemes used to treat Stage I lung cancer with RapidArc were three fractions of 18 Gy, five fractions of 11 Gy, or eight fractions of 7.5 Gy, prescribed at the 80% isodose. Follow-up CT scans performed at less than 6 months (n = 50) and between 6 and 9 months (n = 30) after SBRT were reviewed. Posttreatment scans were coregistered with baseline scans using a B-spline deformable registration algorithm. Voxel-Hounsfield unit histograms were created for doses between 0.5 and 50 Gy. Linear mixed effects models were used to assess the effects of SBRT dose on CT density, and the influence of possible confounders was tested. Results: Increased CT density was associated with higher dose, increasing planning target volume size, and increasing time after SBRT (all p < 0.0001). Density increases were apparent in areas receiving >6 Gy, were most prominent in areas receiving >20 Gy, and seemed to plateau above 40 Gy. In regions receiving >36 Gy, the reduction in air-filled fraction of lung after treatment was up to 18%. No increase in CT density was observed in the contralateral lung receiving {>=}3 Gy. Conclusions: A dose-response relationship exists for quantitative CT density changes after SBRT. A threshold of effect is seen at low doses, and a plateau at highest doses.

  14. Prone breast radiotherapy in early-stage breast cancer: a preliminary analysis

    International Nuclear Information System (INIS)

    Grann, Alison; McCormick, Beryl; Chabner, Elizabeth S.; Gollamudi, Smitha V.; Schupak, Karen D.; Mychalczak, Borys R.; Heerdt, Alexandra S.; Merchant, Thomas E.; Hunt, Margie A.

    2000-01-01

    Purpose: Women with large breasts have marked dose inhomogeneity and often an inferior cosmetic outcome when treated with breast conservation compared to smaller-sized patients. We designed a prone breast board, which both minimizes breast separation and irradiated lung or heart volume. We report feasibility, cosmesis, and preliminary local control and survival for selected women with Stage 0-II breast cancer. Materials and Methods: Fifty-six patients with clinical Stage 0-II breast cancer were treated with lumpectomy and breast irradiation utilizing a prototype prone breast board. A total of 59 breasts were treated. Indications for treatment in the prone position were large or pendulous breast size (n = 57), or a history of cardiopulmonary disease (n = 2). The median bra size was 41D (range, 34D-44EE). Cosmesis was evaluated on a 1-10 (worst-to-best) scale. Results: Acute toxicity included skin erythema (80% of patients experienced Grade I or Grade II erythema), breast edema (72% of patients experienced mild edema), pruritus (20% of patients), and fatigue (20% of patients reported mild fatigue). One patient required a treatment break. The only late toxicity was related to long-term cosmesis. The mean overall cosmesis score for 53 patients was 9.37 (range, 8-10). Actuarial 3- and 5-year local control rates are 98%. Actuarial overall survival at 3 and 5 years are 98% and 94%. Conclusion: Our data indicate that treating selected women with prone breast radiotherapy is feasible and tolerated. The approach results in excellent cosmesis, and short-term outcome is comparable to traditional treatment techniques. This technique offers an innovative alternative to women who might not otherwise be considered candidates for breast conservation

  15. An analysis of patient positioning during stereotactic lung radiotherapy performed without rigid external immobilization.

    Science.gov (United States)

    Dahele, Max; Verbakel, Wilko; Cuijpers, Johan; Slotman, Ben; Senan, Suresh

    2012-07-01

    Intra-fraction patient motion is incompletely understood and the optimum amount of support or immobilization during stereotactic body radiotherapy (SBRT) is unclear. Rigid immobilization is often advocated, but motion still occurs. In contrast, we deliver the vast majority of SBRT using simple supporting devices, simultaneously emphasizing comfort, frequent position checks and progressive reduction in treatment times. We report spine stability during lung SBRT. Patients lie on a thin mattress with arms supported above their head and below-knee support. Stereoscopic spine X-rays before and after fraction delivery identified motion in three translational and three rotational directions. Images from 109 fractions in 30 patients resulted in 327 translational and 327 rotational pre- and post-fraction comparisons. Mean RapidArc® delivery time for variable fraction dose was 4.2 min (SD=1.4). 92% and 97% of translational and rotational differences were ≤1 mm and ≤1° in any direction and 98% of translational differences were ≤1.5mm. Mean vertical, longitudinal and lateral motion was 0mm (SD=0.4), 0mm (0.6) and 0mm (0.6). 84% and 94% of the 109 fractions were delivered with ≤1 and ≤1.5mm translation in all three directions and 93% with ≤1° of rotation. Two patients accounted for 10/17 fractions with >1mm translational motion. Based on pre and post-fraction X-ray imaging during fast lung SBRT, simple support devices can result in spine stability that is comparable to that reported with rigid external immobilization. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  16. Analysis of second malignancies after modern radiotherapy versus prostatectomy for localized prostate cancer

    International Nuclear Information System (INIS)

    Huang Jiayi; Kestin, Larry L.; Ye, Hong; Wallace, Michelle; Martinez, Alvaro A.; Vicini, Frank A.

    2011-01-01

    Purpose: To clarify the risk of developing second primary cancers (SPCs) after radiotherapy (RT) versus prostatectomy for localized prostate cancer (PCa) in the modern era. Methods: The RT cohort consisted of 2120 patients matched on a 1:1 basis with surgical patients according to age and follow-up time. RT techniques consisted of conventional or two-dimensional RT (2DRT, 36%), three-dimensional conformal RT and/or intensity modulated RT (3DCRT/IMRT, 29%), brachytherapy (BT, 16%), and a combination of 2DRT and BT (BT boost, 19%). Results: The overall SPC risk was not significantly different between the matched-pair (HR 1.14, 95% CI 0.94-1.39), but the risk became significant >5 years or >10 years after RT (HR 1.86, 95% CI 1.36-2.55; HR 4.94, 95% CI 2.18-11.2, respectively). The most significant sites of increased risk were bladder, lymphoproliferative, and sarcoma. Of the different RT techniques, only 2DRT was associated with a significantly higher risk (HR 1.76, 95% CI 1.32-2.35), but not BT boost (HR 0.83, 95% CI 0.50-1.38), 3DCRT/IMRT (HR 0.81, 95% CI 0.55-1.21), or BT (HR 0.53, 95% CI 0.28-1.01). Conclusions: Radiation-related SPC risk varies depending on the RT technique and may be reduced by using BT, BT boost, or 3DCRT/IMRT.

  17. Establishment of animal model for the analysis of cancer cell metastasis during radiotherapy

    International Nuclear Information System (INIS)

    Park, Jong Kuk; Jang, Su Jin; Kang, Sung Wook; Park, Sunhoo; Hwang, Sang-Gu; Kim, Wun-Jae; Kang, Joo Hyun; Um, Hong-Duck

    2012-01-01

    Γ-Ionizing radiation (IR) therapy is one of major therapeutic tools in cancer treatment. Nevertheless, γ-IR therapy failed due to occurrence of metastasis, which constitutes a significant obstacle in cancer treatment. The main aim of this investigation was to construct animal model which present metastasis during radiotherapy in a mouse system in vivo and establishes the molecular mechanisms involved. The C6L transfectant cell line expressing firefly luciferase (fLuc) was treated with γ-IR, followed by immunoblotting, zymography and invasion assay in vitro. We additionally employed the C6L transfectant cell line to construct xenografts in nude mice, which were irradiated with γ-IR. Irradiated xenograft-containing mice were analyzed via survival curves, measurement of tumor size, and bioluminescence imaging in vivo and ex vivo. Metastatic lesions in organs of mice were further assessed using RT-PCR, H & E staining and immunohistochemistry. γ-IR treatment of C6L cells induced epithelial-mesenchymal transition (EMT) and increased cell invasion. In irradiated xenograft-containing mice, tumor sizes were decreased dramatically and survival rates extended. Almost all non-irradiated xenograft-containing control mice had died within 4 weeks. However, we also observed luminescence signals in about 22.5% of γ-IR-treated mice. Intestines or lungs of mice displaying luminescence signals contained several lesions, which expressed the fLuc gene and presented histological features of cancer tissues as well as expression of EMT markers. These findings collectively indicate that occurrences of metastases during γ-IR treatment accompanied induction of EMT markers, including increased MMP activity. Establishment of a murine metastasis model during γ-IR treatment should aid in drug development against cancer metastasis and increase our understanding of the mechanisms underlying the metastatic process

  18. SU-F-T-450: The Investigation of Radiotherapy Quality Assurance and Automatic Treatment Planning Based On the Kernel Density Estimation Method

    Energy Technology Data Exchange (ETDEWEB)

    Fan, J; Fan, J; Hu, W; Wang, J [Fudan University Shanghai Cancer Center, Shanghai, Shanghai (China)

    2016-06-15

    Purpose: To develop a fast automatic algorithm based on the two dimensional kernel density estimation (2D KDE) to predict the dose-volume histogram (DVH) which can be employed for the investigation of radiotherapy quality assurance and automatic treatment planning. Methods: We propose a machine learning method that uses previous treatment plans to predict the DVH. The key to the approach is the framing of DVH in a probabilistic setting. The training consists of estimating, from the patients in the training set, the joint probability distribution of the dose and the predictive features. The joint distribution provides an estimation of the conditional probability of the dose given the values of the predictive features. For the new patient, the prediction consists of estimating the distribution of the predictive features and marginalizing the conditional probability from the training over this. Integrating the resulting probability distribution for the dose yields an estimation of the DVH. The 2D KDE is implemented to predict the joint probability distribution of the training set and the distribution of the predictive features for the new patient. Two variables, including the signed minimal distance from each OAR (organs at risk) voxel to the target boundary and its opening angle with respect to the origin of voxel coordinate, are considered as the predictive features to represent the OAR-target spatial relationship. The feasibility of our method has been demonstrated with the rectum, breast and head-and-neck cancer cases by comparing the predicted DVHs with the planned ones. Results: The consistent result has been found between these two DVHs for each cancer and the average of relative point-wise differences is about 5% within the clinical acceptable extent. Conclusion: According to the result of this study, our method can be used to predict the clinical acceptable DVH and has ability to evaluate the quality and consistency of the treatment planning.

  19. SU-F-T-450: The Investigation of Radiotherapy Quality Assurance and Automatic Treatment Planning Based On the Kernel Density Estimation Method

    International Nuclear Information System (INIS)

    Fan, J; Fan, J; Hu, W; Wang, J

    2016-01-01

    Purpose: To develop a fast automatic algorithm based on the two dimensional kernel density estimation (2D KDE) to predict the dose-volume histogram (DVH) which can be employed for the investigation of radiotherapy quality assurance and automatic treatment planning. Methods: We propose a machine learning method that uses previous treatment plans to predict the DVH. The key to the approach is the framing of DVH in a probabilistic setting. The training consists of estimating, from the patients in the training set, the joint probability distribution of the dose and the predictive features. The joint distribution provides an estimation of the conditional probability of the dose given the values of the predictive features. For the new patient, the prediction consists of estimating the distribution of the predictive features and marginalizing the conditional probability from the training over this. Integrating the resulting probability distribution for the dose yields an estimation of the DVH. The 2D KDE is implemented to predict the joint probability distribution of the training set and the distribution of the predictive features for the new patient. Two variables, including the signed minimal distance from each OAR (organs at risk) voxel to the target boundary and its opening angle with respect to the origin of voxel coordinate, are considered as the predictive features to represent the OAR-target spatial relationship. The feasibility of our method has been demonstrated with the rectum, breast and head-and-neck cancer cases by comparing the predicted DVHs with the planned ones. Results: The consistent result has been found between these two DVHs for each cancer and the average of relative point-wise differences is about 5% within the clinical acceptable extent. Conclusion: According to the result of this study, our method can be used to predict the clinical acceptable DVH and has ability to evaluate the quality and consistency of the treatment planning.

  20. Primary radiotherapy or postoperative radiotherapy in patients with head and neck cancer. Comparative analysis of inflammation-based prognostic scoring systems

    Energy Technology Data Exchange (ETDEWEB)

    Selzer, Edgar; Grah, Anja [Medical University of Vienna, Department of Radiotherapy, Vienna (Austria); Heiduschka, Gregor; Thurnher, Dietmar [Medical University of Vienna, Otorhinolaryngology - Head and Neck Surgery, Vienna (Austria); Kornek, Gabriela [Medical University of Vienna, Medicine I - Division of Clinical Oncology, Vienna (Austria)

    2015-01-13

    Inflammation-based scoring systems have potential value in evaluating the prognosis of cancer patients; however, detailed comparative analyses in well-characterized head and neck cancer patient collectives are missing. We analyzed overall survival (OS) in locally advanced head and neck cancer patients who were treated with curative intent by primary radiotherapy (RT) alone, by RT in combination with cetuximab (RIT) or with cisplatin (RCHT), and by primary surgery followed by postoperative radiotherapy (PORT). The primary RT collective (N = 170) was analyzed separately from the surgery plus RT group (N = 148). OS was estimated using the Kaplan-Meyer method. Cox proportional-hazard regression models were applied to compare the risk of death among patients stratified according to risk factors and the inflammation-based Glasgow Prognostic Score (GPS), the modified GPS (mGPS), the neutrophil-lymphocyte ratio (NLR), the platelet-lymphocyte ratio (PLR), and the prognostic index (PI). A prognostic relevance of the scoring systems for OS was observed in the primarily irradiated, but not in the PORT collective. OS was 35.5, 18.8, and 15.4 months, respectively, according to GPS 0, 1, and 2. OS according to mGPS 0-2 was identical. The PLR scoring system was not of prognostic relevance, while OS was 27.3 months in the NLR 0 group and 17.3 months in the NLR 1 group. OS was 35.5 months in PI 0, 16.1 months in PI 1, and 22.6 months in PI 2. GPS/mGPS scoring systems are able to discriminate between three risk groups in primarily, but not postoperatively irradiated locally advanced head and neck cancer patients. (orig.) [German] Entzuendungsbasierte Bewertungssysteme haben eine potenzielle Bedeutung fuer die Beurteilung der Prognose von Krebspatienten. Derzeit fehlen jedoch ausreichend detailliert durchgefuehrte Analysen in Kollektiven von Patienten mit Kopf-Hals-Tumoren. Untersucht wurde das Gesamtueberleben (''overall survival'', OS) von Patienten mit lokal

  1. Radiotherapy of prostate cancer

    International Nuclear Information System (INIS)

    Krause, S.; Herfarth, K.

    2011-01-01

    With the development of modern radiation techniques, such as intensity-modulated radiotherapy (IMRT), a dose escalation in the definitive radiotherapy of prostate cancer and a consecutive improvement in biochemical recurrence-free survival (BFS) could be achieved. Among others, investigators at the Memorial Sloan-Kettering Cancer Center (MSKCC) saw 5-year BFS rates of up to 98%. A further gain in effectiveness and safety is expected of hypofractionation schedules, as suggested by data published by Kupelian et al., who saw a low 5-year rate of grade ≥2 rectal side-effects of 4.5%. However, randomized studies are just beginning to mature. Patients with intermediate or high-risk tumors should receive neoadjuvant (NHT) and adjuvant (AHT) androgen deprivation. Bolla et al. could show an increase in 5-year overall survival from 62-78%. The inclusion of the whole pelvis in the treatment field (WPRT) is still controversial. The RTOG 94-13 study showed a significant advantage in disease-free survival after 60 months but long-term data did not yield significant differences between WPRT and irradiation of the prostate alone. The German Society of Urology strongly recommends adjuvant radiotherapy of the prostate bed for pT3 N0 tumors with positive margins. In a pT3 N0 R0 or pT2 N0 R+ situation, adjuvant radiotherapy should at least be considered. So far, no randomized data on NHT and AHT have been published, so androgen deprivation remains an individual decision in the postoperative setting. In a retrospective analysis Spiotto et al. reported a positive effect for adjuvant WPRT and biochemical control. This article summarizes the essential publications on definitive and adjuvant radiotherapy and discusses the additional use of androgen deprivation and WPRT. (orig.) [de

  2. Transcatheter arterial chemoembolization in combination with radiotherapy for unresectable hepatocellular carcinoma: A systematic review and meta-analysis

    International Nuclear Information System (INIS)

    Meng Maobin; Cui Yaoli; Lu You; She Bin; Chen Yan; Guan Yongsong; Zhang Ruiming

    2009-01-01

    Background and Purpose: To evaluate the efficacy and safety of transcatheter arterial chemoembolization (TACE) plus radiotherapy (RT) for unresectable hepatocellular carcinoma (UHCC) using meta-analysis of data from the literature involving available randomized controlled trials of TACE in combination with RT compared with that of TACE alone (Therapy I versus II) in treating UHCC. Material and Methods: We searched the Cochrane Library, MEDLINE, CENTRAL, EMBASE, CBMdisc, and CNKI as well as employing manual searches. Meta-analysis was performed on the results of homogeneous studies. Analyses subdivided by study design were also performed. Results: We found 17 trials involving 1476 patients. 5 of total were Randomized Controlled Trials (RCTs) and 12 were Non-randomized Controlled Clinical Trials (CCTs). In terms of quality, 5 RCTs were graded B, and 12 CCTs were graded C. Our results showed that Therapy I, compared with Therapy II, significantly improved the survival and the tumor response of patients, and was thus more therapeutically beneficial. Serious adverse events were not increased exception for total bilirubin (TB) level. Conclusions: Therapy I was more therapeutically beneficial. However, considering the strength of the evidence, additional randomized controlled trials are needed before Therapy I can be recommended routinely.

  3. Analysis of risk assessment of brachytherapy from the radiotherapy services of the metropolitan region of Rio de Janeiro, RJ, Brazil

    International Nuclear Information System (INIS)

    Burgos, Adam de Freitas; Paiva, Eduardo de; Souza, Roberto Salomon de

    2014-01-01

    Currently there are few applications on the risk analysis procedures related to radiotherapy, mainly in the practice of brachytherapy. The objective of this study was to analyze the perception of risk levels, present in the practice of high dose rate brachytherapy (HDR), using a form based on the concept of the risk matrix and a database (SEVRRA) containing information about the processes related to routine brachytherapy. A form containing information regarding the brachytherapy procedure HDR and an attachment indicating how to complete it properly was delivered to a medical physicist of each service/institution. The reference value for the risk levels found, considered acceptable for all performed analyzes, was set at a percentage limit of 33% (assuming a failure in each 3 existing processes). The results showed that the overall risk analysis showed a value for average percentage of prioritized risk of 18% below the recommended range. About the analyzed groups, the higher average percentage of relative risk was found less than 12% of the recommended range, associated with the group of patients. On existing steps, the highest average percentage of relative risk was found less than 1% of the recommended range, associated with stage records and treatment planning. This study showed that although this procedure does not have a large history of accidents, still poses risks considerable that must be managed with great accuracy and immediate action to an effective decrease these risk percentages

  4. A retrospective analysis of survival outcomes for two different radiotherapy fractionation schedules given in the same overall time for limited stage small cell lung cancer

    International Nuclear Information System (INIS)

    Bettington, Catherine S.; Bryant, Guy; Hickey, Brigid; Tripcony, Lee; Pratt, Gary; Fay, Michael

    2013-01-01

    To compare survival outcomes for two fractionation schedules of thoracic radiotherapy, both given over 3 weeks, in patients with limited stage small cell lung cancer (LS-SCLC). At Radiation Oncology Mater Centre (ROMC) and the Royal Brisbane and Women's Hospital (RBWH), patients with LS-SCLC treated with curative intent are given radiotherapy (with concurrent chemotherapy) to a dose of either 40Gy in 15 fractions ('the 40Gy/15⧣group') or 45Gy in 30 fractions ('the 45Gy/30⧣group'). The choice largely depends on institutional preference. Both these schedules are given over 3 weeks, using daily and twice-daily fractionation respectively. The records of all such patients treated from January 2000 to July 2009 were retrospectively reviewed and survival outcomes between the two groups compared. Of 118 eligible patients, there were 38 patients in the 40Gy/15⧣ group and 41 patients in the 45Gy/30⧣ group. The median relapse-free survival time was 12 months in both groups. Median overall survival was 21 months (95% CI 2–37 months) in the 40Gy/15⧣ group and 26 months (95% CI 1–48 months) in the 45Gy/30⧣ group. The 5-year overall survival rates were 20% and 25%, respectively (P=0.24). On multivariate analysis, factors influencing overall survival were: whether prophylactic cranial irradiation (PCI) was given (P=0.01) and whether salvage chemotherapy was given at the time of relapse (P=0.057). Given the small sample size, the potential for selection bias and the retrospective nature of our study it is not possible to draw firm conclusions regarding the efficacy of hypofractionated thoracic radiotherapy compared with hyperfractionated accelerated thoracic radiotherapy however hypofractionated radiotherapy may result in equivalent relapse-free survival.

  5. Feasibility and potential utility of multicomponent exhaled breath analysis for predicting development of radiation pneumonitis after stereotactic ablative radiotherapy.

    Science.gov (United States)

    Moré, Jayaji M; Eclov, Neville C W; Chung, Melody P; Wynne, Jacob F; Shorter, Joanne H; Nelson, David D; Hanlon, Alexandra L; Burmeister, Robert; Banos, Peter; Maxim, Peter G; Loo, Billy W; Diehn, Maximilian

    2014-07-01

    In this prospective pilot study, we evaluated the feasibility and potential utility of measuring multiple exhaled gases as biomarkers of radiation pneumonitis (RP) in patients receiving stereotactic ablative radiotherapy (SABR) for lung tumors. Breath analysis was performed for 26 patients receiving SABR for lung tumors. Concentrations of exhaled nitric oxide (eNO), carbon monoxide (eCO), nitrous oxide (eN2O), and carbon dioxide (eCO2) were measured before and immediately after each fraction using real-time, infrared laser spectroscopy. RP development (CTCAE grade ≥2) was correlated with baseline gas concentrations, acute changes in gas concentrations after each SABR fraction, and dosimetric parameters. Exhaled breath analysis was successfully completed in 77% of patients. Five of 20 evaluable patients developed RP at a mean of 5.4 months after SABR. Acute changes in eNO and eCO concentrations, defined as percent changes between each pre-fraction and post-fraction measurement, were significantly smaller in RP versus non-RP cases (p = 0.022 and 0.015, respectively). In an exploratory analysis, a combined predictor of baseline eNO greater than 24 parts per billion and acute decrease in eCO less than 5.5% strongly correlated with RP incidence (p =0.0099). Neither eN2O nor eCO2 concentrations were significantly associated with RP development. Although generally higher in patients destined to develop RP, dosimetric parameters were not significantly associated with RP development. The majority of SABR patients in this pilot study were able to complete exhaled breath analysis. Baseline concentrations and acute changes in concentrations of exhaled breath components were associated with RP development after SABR. If our findings are validated, exhaled breath analysis may become a useful approach for noninvasive identification of patients at highest risk for developing RP after SABR.

  6. Conformation radiotherapy and conformal radiotherapy

    International Nuclear Information System (INIS)

    Morita, Kozo

    1999-01-01

    In order to coincide the high dose region to the target volume, the 'Conformation Radiotherapy Technique' using the multileaf collimator and the device for 'hollow-out technique' was developed by Prof. S. Takahashi in 1960. This technique can be classified a type of 2D-dynamic conformal RT techniques. By the clinical application of this technique, the late complications of the lens, the intestine and the urinary bladder after radiotherapy for the maxillary cancer and the cervical cancer decreased. Since 1980's the exact position and shape of the tumor and the surrounding normal tissues can be easily obtained by the tremendous development of the CT/MRI imaging technique. As a result, various kinds of new conformal techniques such as the 3D-CRT, the dose intensity modulation, the tomotherapy have been developed since the beginning of 1990'. Several 'dose escalation study with 2D-/3D conformal RT' is now under way to improve the treatment results. (author)

  7. Postoperative radiotherapy dose requirement in standard combined-modality practice for head and neck squamous cell carcinoma: Analysis of salient surgical and radiotherapy parameters in 2 cohorts.

    Science.gov (United States)

    Mohanti, Bidhu K; Thakar, Alok; Kaur, Jaspreet; Bahadur, Sudhir; Malik, Monica; Gandhi, Ajeet K; Bhasker, Suman; Sharma, Atul

    2017-09-01

    This study compared 2 sequential cohorts to identify the postoperative radiotherapy (PORT) dose requirement for head and neck squamous cell carcinoma (HNSCC). Two distinct PORT dose regimens were prescribed over 11 years; group 1 received 56 Gy or less, and group 2 received 60 Gy or more. The 2D and 3D techniques were used. Two sequential cohorts consisted of 478 patients, with mean and median follow-up for group 1 and 2 as: 37.0 versus 28.5 months and 13.8 versus 13.1 months, respectively. Grades 3-4 mucosal toxicities (11.4% vs 28.3%), hospitalization (3.2% vs 17.4%), and nasogastric feeding (11.9% vs 29.7%) were higher in group 2. The 2-year disease-free survival (DFS) was higher with PORT >60 Gy for the following factors: age ≤ 50 years (P = .041); ≥ 4 positive nodes (P = .029); and overall treatment time (OTT) ≥ 100 days (P = .042). Except for the benefit of doses >60 Gy for limited parameters, a lower PORT dose did not compromise the results and can potentially reduce the morbidities and healthcare costs. © 2017 Wiley Periodicals, Inc.

  8. An investigation of anxiety about radiotherapy deploying the radiotherapy categorical anxiety scale

    International Nuclear Information System (INIS)

    Shimotsu, Sakie; Karasawa, Kumiko; Ito, Kana; Saito, Anneyuko I.; Izawa, Hiromi; Kawase, Eri; Horikawa, Naoshi

    2010-01-01

    Radiotherapy is one of the major methods for treating cancer, but many patients undergoing radiotherapy have deep concerns about receiving radiation treatment. This problem is not generally appreciated and has not been adequately studied. The objective of this investigation was to empirically investigate the anxieties that cancer patients feel towards radiotherapy by using questionnaires to classify and quantitatively measure their concerns. A preliminary interview to develop a questionnaire was carried out with 48 patients receiving radiotherapy to discover their anxieties about on-going treatments. Subsequently, a main study was performed using a questionnaire with 185 patients to classify their types of anxiety and to ascertain the reliability and validity of the responses. Confirmatory factor analysis was then carried out with a 17-item Radiotherapy Categorical Anxiety Scale. Three anxiety factors were abstracted by factor analysis: adverse effects of radiotherapy, environment of radiotherapy, and treatment effects of radiotherapy. Reliability, content validity, and concurrent validity were obtained. The adequacy of the three-factor model of anxiety concerning radiotherapy was confirmed. A 17-item Radiotherapy Categorical Anxiety Scale was formulated to quantitatively measure the specific types of anxiety among cancer patients receiving radiotherapy. (author)

  9. Analysis of Carina Position as Surrogate Marker for Delivering Phase-Gated Radiotherapy

    International Nuclear Information System (INIS)

    Weide, Lineke van der; Soernsen de Koste, John R. van; Lagerwaard, Frank J.; Vincent, Andrew; Triest, Baukelien van; Slotman, Ben J.; Senan, Suresh

    2008-01-01

    Purpose: Respiratory gating can mitigate the effect of tumor mobility in radiotherapy (RT) for lung cancer. Because the tumor is generally not visualized, external surrogates of tumor position are used to trigger respiration-gated RT. We evaluated the suitability of the carina position as a surrogate in respiration-gated RT. Methods and Materials: A total of 30 four-dimensional (4D) computed tomography (CT) scans from 14 patients with lung cancer were retrospectively analyzed. Both uncoached (free breathing) and audio-coached 4D-CT scans were acquired from 9 patients, and 12 uncoached 4D-CT scans were acquired from 5 other patients during a 2-4-week period of stereotactic RT. The repeat scans were co-registered. The carina position was identified on the coronal cut planes in all 4D-CT phases. The correlation between the carina position and the total lung volume for each phase was determined, and the reproducibility of the carina position was studied in the 5 patients with repeat uncoached 4D-CT scans. Results: The mean extent of carina motion in 21 uncoached scans was 5.3 ± 1.6 mm in the craniocaudal (CC), 2.3 ± 1.4 mm in the anteroposterior, and 1.5 ± 0.7 mm in the mediolateral direction. Audio coaching resulted in a twofold increase in carina mobility in all directions. The CC carina position correlated with changes in the total lung volume (R = 0.89 ± 0.14), but the correlation was better for the audio-coached than for the uncoached 4D-CT scans (R = 0.93 ± 0.08 vs. R = 0.85 ± 0.17; paired t test, p = 0.034). Preliminary data from the 5 patients indicated that the CC carina motion correlated better with tumor motion than did the motion of the diaphragm. Conclusions: The CC position of the carina correlated well with the total lung volume, indicating that the carina is a good surrogate for verifying the total lung volume during respiration-gated RT

  10. Intensity-modulated radiotherapy (IMRT) for carcinoma of the maxillary sinus: A comparison of IMRT planning systems

    International Nuclear Information System (INIS)

    Ahmed, Raef S.; Ove, Roger; Duan, Jun; Popple, Richard; Cobb, Glenn

    2006-01-01

    The treatment of maxillary sinus carcinoma with forward planning can be technically difficult when the neck also requires radiotherapy. This difficulty arises because of the need to spare the contralateral face while treating the bilateral neck. There is considerable potential for error in clinical setup and treatment delivery. We evaluated intensity-modulated radiotherapy (IMRT) as an improvement on forward planning, and compared several inverse planning IMRT platforms. A composite dose-volume histogram (DVH) was generated from a complex forward planned case. We compared the results with those generated by sliding window fixed field dynamic multileaf collimator (MLC) IMRT, using sets of coplanar beams. All setups included an anterior posterior (AP) beam, and 3-, 5-, 7-, and 9-field configurations were evaluated. The dose prescription and objective function priorities were invariant. We also evaluated 2 commercial tomotherapy IMRT delivery platforms. DVH results from all of the IMRT approaches compared favorably with the forward plan. Results for the various inverse planning approaches varied considerably across platforms, despite an attempt to prescribe the therapy similarly. The improvement seen with the addition of beams in the fixed beam sliding window case was modest. IMRT is an effective means of delivering radiotherapy reliably in the complex setting of maxillary sinus carcinoma with neck irradiation. Differences in objective function definition and optimization algorithms can lead to unexpected differences in the final dose distribution, and our evaluation suggests that these factors are more significant than the beam arrangement or number of beams

  11. WE-G-BRA-06: Application of Systems and Control Theory-Based Hazard Analysis to Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Pawlicki, T [UC San Diego, La Jolla, CA (United States); Samost, A; Leveson, N [Massachusetts Institute of Technology, Cambridge, MA (United States)

    2015-06-15

    Purpose: The process of delivering radiation occurs in a complex socio-technical system heavily reliant on human operators. Furthermore, both humans and software are notoriously challenging to account for in traditional hazard analysis models. High reliability industries such as aviation have approached this problem through using hazard analysis techniques grounded in systems and control theory. The purpose of this work is to apply the Systems Theoretic Accident Model Processes (STAMP) hazard model to radiotherapy. In particular, the System-Theoretic Process Analysis (STPA) approach is used to perform a hazard analysis of a proposed on-line adaptive cranial radiosurgery procedure that omits the CT Simulation step and uses only CBCT for planning, localization, and treatment. Methods: The STPA procedure first requires the definition of high-level accidents and hazards leading to those accidents. From there, hierarchical control structures were created followed by the identification and description of control actions for each control structure. Utilizing these control structures, unsafe states of each control action were created. Scenarios contributing to unsafe control action states were then identified and translated into system requirements to constrain process behavior within safe boundaries. Results: Ten control structures were created for this new CBCT-only process which covered the areas of hospital and department management, treatment design and delivery, and vendor service. Twenty three control actions were identified that contributed to over 80 unsafe states of those control actions resulting in over 220 failure scenarios. Conclusion: The interaction of people, hardware, and software are highlighted through the STPA approach. STPA provides a hierarchical model for understanding the role of management decisions in impacting system safety so that a process design requirement can be traced back to the hazard and accident that it is intended to mitigate. Varian

  12. Prospective feasibility analysis of a novel off-line approach for MR-guided radiotherapy.

    Science.gov (United States)

    Bostel, Tilman; Pfaffenberger, Asja; Delorme, Stefan; Dreher, Constantin; Echner, Gernot; Haering, Peter; Lang, Clemens; Splinter, Mona; Laun, Frederik; Müller, Marco; Jäkel, Oliver; Debus, Jürgen; Huber, Peter E; Sterzing, Florian; Nicolay, Nils H

    2018-05-01

    The present work aimed to analyze the feasibility of a shuttle-based MRI-guided radiation therapy (MRgRT) in the treatment of pelvic malignancies. 20 patients with pelvic malignancies were included in this prospective feasibility analysis. Patients underwent daily MRI in treatment position prior to radiotherapy at the German Cancer Research Center. Positional inaccuracies, time and patient compliance were assessed for the application of off-line MRgRT. In 78% of applied radiation fractions, MR imaging for position verification could be performed without problems. Additionally, treatment-related side effects and reduced patient compliance were only responsible for omission of MRI in 9% of radiation fractions. The study workflow took a median time of 61 min (range 47-99 min); duration for radiotherapy alone was 13 min (range 7-26 min). Patient positioning, MR imaging and CT imaging including patient repositioning and the shuttle transfer required median times of 10 min (range 7-14 min), 26 min (range 15-60 min), 5 min (range 3-8 min) and 8 min (range 2-36 min), respectively. To assess feasibility of shuttle-based MRgRT, the reference point coordinates for the x, y and z axis were determined for the MR images and CT obtained prior to the first treatment fraction and correlated with the coordinates of the planning CT. In our dataset, the median positional difference between MR imaging and CT-based imaging based on fiducial matching between MR and CT imaging was equal to or less than 2 mm in all spatial directions. The limited space in the MR scanner influenced patient selection, as the bore of the scanner had to accommodate the immobilization device and the constructed stereotactic frame. Therefore, obese, extremely muscular or very tall patients could not be included in this trial in addition to patients for whom exposure to MRI was generally judged inappropriate. This trial demonstrated for the first time the feasibility and patient

  13. Preclinical dynamic 18F-FDG PET - tumor characterization and radiotherapy response assessment by kinetic compartment analysis

    International Nuclear Information System (INIS)

    Roee, Kathrine; Aleksandersen, Thomas B.; Nilsen, Line B.; Hong Qu; Ree, Anne H.; Malinen, Eirik; Kristian, Alexandr; Seierstad, Therese; Olsen, Dag R.

    2010-01-01

    Background. Non-invasive visualization of tumor biological and molecular processes of importance to diagnosis and treatment response is likely to be critical in individualized cancer therapy. Since conventional static 18 F-FDG PET with calculation of the semi-quantitative parameter standardized uptake value (SUV) may be subject to many sources of variability, we here present an approach of quantifying the 18 F-FDG uptake by analytic two-tissue compartment modeling, extracting kinetic tumor parameters from dynamic 18 F-FDG PET. Further, we evaluate the potential of such parameters in radiotherapy response assessment. Material and methods. Male, athymic mice with prostate carcinoma xenografts were subjected to dynamic PET either untreated (n=8) or 24 h post-irradiation (7.5 Gy single dose, n=8). After 10 h of fasting, intravenous bolus injections of 10-15 MBq 18 F-FDG were administered and a 1 h dynamic PET scan was performed. 4D emission data were reconstructed using OSEM-MAP, before remote post-processing. Individual arterial input functions were extracted from the image series. Subsequently, tumor 18 F-FDG uptake was fitted voxel-by-voxel to a compartment model, producing kinetic parameter maps. Results. The kinetic model separated the 18 F-FDG uptake into free and bound tracer and quantified three parameters; forward tracer diffusion (k1), backward tracer diffusion (k2), and rate of 18 F-FDG phosphorylation, i.e. the glucose metabolism (k3). The fitted kinetic model gave a goodness of fit (r2) to the observed data ranging from 0.91 to 0.99, and produced parametrical images of all tumors included in the study. Untreated tumors showed homogeneous intra-group median values of all three parameters (k1, k2 and k3), whereas the parameters significantly increased in the tumors irradiated 24 h prior to 18 F-FDG PET. Conclusions. This study demonstrates the feasibility of a two-tissue compartment kinetic analysis of dynamic 18 F-FDG PET images. If validated, extracted

  14. Postmastectomy radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Shikama, Naoto; Koguchi, Masahiko; Sasaki, Shigeru; Kaneko, Tomoki; Shinoda, Atsunori; Nishikawa, Atsushi [Shinshu Univ., Matsumoto, Nagano (Japan). School of Medicine

    2000-10-01

    Since there have been few reports on postmastectomy radiotherapy having a high evidence level in Japan, the significance of postoperative radiotherapy and the irradiation techniques were reviewed based on reports from Western countries. Authors focused on the indications for postoperative irradiation, irradiation methods (irradiation sites, irradiation techniques; prosthetics, methods of irradiating the chest wall and lymph nodes, timing of irradiation), and complications, and discuss them. The factors thought to be adaptable to postmastectomy radiotherapy have been listed. Axillary lymph node metastasis and the size of the primary focus are thought to be important factors in locoregional recurrence. The chest wall and the supraclavicular lymph nodes are the usual sites of irradiation after mastectomy. The irradiation method consists of tangential irradiation of the chest wall and single-field irradiation of the supraclavicular lymph nodes, with 46-50 Gy in fractional doses of 1.8-2 Gy x 5/w is administered for 4.5-5.5 weeks. The timing of irradiation in the West is generally after chemotherapy. Adverse radiation effects include ischemic heart disease, pneumonitis, arm edema, rib fractures, and brachial plexus paralysis. The frequency of these complications is increased by the combined use of chemotherapy or surgery. The breast cancer cure rate in Japan is generally better than in the West. It remains to be determined whether the clinical data from Europe and America are applicable to the treatment of breast cancer in Japan. To address this issue, a clinical investigation should be performed in Japan with close cooperation between surgeons, physicians, pathologists, and radiotherapists. (K.H.)

  15. Prospective approaches for risk analysis in modern radiotherapy: the Italian experience and the contribution of medical physicists

    International Nuclear Information System (INIS)

    Begnozzi, L.; Cantone, M.C.; Veronese, I.; Longobardi, B.

    2014-01-01

    In the last few years there has been significant development of radiation therapy (RT) equipment with advanced imaging and delivery techniques, as well as treatment planning systems. From this perspective, proactive approaches for risk assessment were identified as a powerful tool in modern radiation oncology. A multidisciplinary working group (WG) has been established in the framework of the Italian association for medical physics (AIFM) to promote the use of prospective approaches in the radiotherapy scientific community. This paper describes the main actions carried out by the WG in order to collect information about the engagement of Italian medical physicists in the risk management process, in reporting possible incidents in RT and in the procedures of collecting and analysing near misses. In particular, the main scope of the study was to evaluate the actual level of experience in use of proactive risk analysis tools in modern RT by medical physicists. Finally, the measures implemented by the WG in order to promote the use of such approaches, and consequently to contribute to enhancing safety and radiation protection culture in radiation oncology are described. (authors)

  16. Clinical Factors Predicting Late Severe Urinary Toxicity After Postoperative Radiotherapy for Prostate Carcinoma: A Single-Institute Analysis of 742 Patients

    Energy Technology Data Exchange (ETDEWEB)

    Cozzarini, Cesare, E-mail: cozzarini.cesare@hsr.it [Department of Radiotherapy, San Raffaele Scientific Institute, Milan (Italy); Fiorino, Claudio [Department of Medical Physics, San Raffaele Scientific Institute, Milan (Italy); Da Pozzo, Luigi Filippo [Department of Urology, San Raffaele Scientific Institute, Milan (Italy); Alongi, Filippo; Berardi, Genoveffa; Bolognesi, Angelo [Department of Radiotherapy, San Raffaele Scientific Institute, Milan (Italy); Briganti, Alberto [Department of Urology, San Raffaele Scientific Institute, Milan (Italy); Broggi, Sara [Department of Medical Physics, San Raffaele Scientific Institute, Milan (Italy); Deli, Aniko [Department of Radiotherapy, San Raffaele Scientific Institute, Milan (Italy); Guazzoni, Giorgio [Department of Urology, San Raffaele Scientific Institute, Milan (Italy); Perna, Lucia [Department of Medical Physics, San Raffaele Scientific Institute, Milan (Italy); Pasetti, Marcella; Salvadori, Giovannella [Department of Radiotherapy, San Raffaele Scientific Institute, Milan (Italy); Montorsi, Francesco; Rigatti, Patrizio [Department of Urology, San Raffaele Scientific Institute, Milan (Italy); Di Muzio, Nadia [Department of Radiotherapy, San Raffaele Scientific Institute, Milan (Italy)

    2012-01-01

    Purpose: To investigate the clinical factors independently predictive of long-term severe urinary sequelae after postprostatectomy radiotherapy. Patients and Methods: Between 1993 and 2005, 742 consecutive patients underwent postoperative radiotherapy with either adjuvant (n = 556; median radiation dose, 70.2 Gy) or salvage (n = 186; median radiation dose, 72 Gy) intent. Results: After a median follow-up of 99 months, the 8-year risk of Grade 2 or greater and Grade 3 late urinary toxicity was almost identical (23.9% vs. 23.7% and 12% vs. 10%) in the adjuvant and salvage cohorts, respectively. On univariate analysis, acute toxicity was significantly predictive of late Grade 2 or greater sequelae in both subgroups (p <.0001 in both cases), and hypertension (p = .02) and whole-pelvis radiotherapy (p = .02) correlated significantly in the adjuvant cohort only. The variables predictive of late Grade 3 sequelae were acute Grade 2 or greater toxicity in both groups and whole-pelvis radiotherapy (8-year risk of Grade 3 events, 21% vs. 11%, p = .007), hypertension (8-year risk, 18% vs. 10%, p = .005), age {<=} 62 years at RT (8-year risk, 16% vs. 11%, p = .04) in the adjuvant subset, and radiation dose >72 Gy (8-year risk, 19% vs. 6%, p = .007) and age >71 years (8-year risk, 16% vs. 6%, p = .006) in the salvage subgroup. Multivariate analysis confirmed the independent predictive role of all the covariates indicated as statistically significant on univariate analysis. Conclusions: The risk of late Grade 2 or greater and Grade 3 urinary toxicity was almost identical, regardless of the RT intent. In the salvage cohort, older age and greater radiation doses resulted in a worse toxicity profile, and younger, hypertensive patients experienced a greater rate of severe late sequelae in the adjuvant setting. The causes of this latter correlation and apparently different etiopathogenesis of chronic damage in the two subgroups were unclear and deserve additional investigation.

  17. Systemic analysis of different colorectal cancer cell lines and TCGA datasets identified IGF-1R/EGFR-PPAR-CASPASE axis as important indicator for radiotherapy sensitivity.

    Science.gov (United States)

    Chen, Lin; Zhu, Zhe; Gao, Wei; Jiang, Qixin; Yu, Jiangming; Fu, Chuangang

    2017-09-05

    Insulin-like growth factor 1 receptor (IGF-1R) is proved to contribute the development of many types of cancers. But, little is known about its roles in radio-resistance of colorectal cancer (CRC). Here, we demonstrated that low IGF-1R expression value was associated with the better radiotherapy sensitivity of CRC. Besides, through Quantitative Real-time PCR (qRT-PCR), the elevated expression value of epidermal growth factor receptor (EGFR) was observed in CRC cell lines (HT29, RKO) with high radio-sensitivity compared with those with low sensitivity (SW480, LOVO). The irradiation induced apoptosis rates of wild type and EGFR agonist (EGF) or IGF-1R inhibitor (NVP-ADW742) treated HT29 and SW480 cells were quantified by flow cytometry. As a result, the apoptosis rate of EGF and NVP-ADW742 treated HT29 cells was significantly higher than that of those wild type ones, which indicated that high EGFR and low IGF-1R expression level in CRC was associated with the high sensitivity to radiotherapy. We next conducted systemic bioinformatics analysis of genome-wide expression profiles of CRC samples from the Cancer Genome Atlas (TCGA). Differential expression analysis between IGF-1R and EGFR abnormal CRC samples, i.e. CRC samples with higher IGF-1R and lower EGFR expression levels based on their median expression values, and the rest of CRC samples identified potential genes contribute to radiotherapy sensitivity. Functional enrichment of analysis of those differential expression genes (DEGs) in the Database for Annotation, Visualization and Integrated Discovery (DAVID) indicated PPAR signaling pathway as an important pathway for the radio-resistance of CRC. Our study identified the potential biomarkers for the rational selection of radiotherapy for CRC patients. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Concurrent cisplatin-based chemoradiotherapy versus exclusive radiotherapy in high-risk cervical cancer: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Meng XY

    2016-03-01

    Full Text Available Xiang-Yu Meng,1,* Yi Liao,2,* Xiao-Ping Liu,3 Sheng Li,1 Ming-Jun Shi,4 Xian-Tao Zeng11Center for Evidence-Based and Translational Medicine, Zhongnan Hospital of Wuhan University, Wuhan, Hubei Province, People’s Republic of China; 2Department of Oncology, Nanfang Hospital, Southern Medical University, GuangZhou Province, People’s Republic of China; 3Department of Hematology and Oncology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei Province, People’s Republic of China; 4Institut Curie, Paris Sciences et Lettres Research University, Le Centre National de la Recherche Scientifique, Les Unités Mixtes de Recherche 144, F-75005, Paris, France*These authors contributed equally to this workObjective: To evaluate the efficacy and safety of cisplatin-based concurrent chemoradiotherapy (DDP-CCRT in patients with high-risk cervical carcinoma (CC compared with exclusive radiotherapy (RT.Materials and methods: Databases were searched for randomized controlled trials (RCTs and cohort studies comparing DDP-CCRT with RT alone. Risk of bias assessment for RCTs was performed using the Cochrane Collaboration’s tool, and the Newcastle–Ottawa quality scale was used to perform quality assessment for cohort studies. Meta-analysis was conducted using Review Manager 5 and Stata 12.0 software.Results: Finally, eight RCTs and three cohort studies containing 2,130 subjects were included. Analysis on total failures revealed a statistically significant difference in favor of DDP-CCRT (risk ratio =0.77, 95% confidence intervals [CIs]: 0.67–0.89. No significant heterogeneity was detected for pooled analysis concerning overall survival; the result of which demonstrated the superiority of DDP-CCRT over RT alone (hazard ratio =0.68, 95% CI: 0.57–0.80, and stable and established accumulative effects were observed in cumulative meta-analysis. Similar results were observed for progression-free survival (hazard ratio =0.63, 95% CI: 0.50–0.76. In terms of

  19. The situation of radiotherapy in 2011

    International Nuclear Information System (INIS)

    2012-06-01

    Published within the frame of the French 2009-2013 cancer plan, this report proposes an analysis of the situation of radiotherapy in France. More particularly, it analyses the French offer in terms of radiotherapy treatments and the French position in Europe. A second part analyses equipment (accelerators and other equipment) and techniques aimed at radiotherapy treatment preparation and delivery. The following techniques are addressed: three-dimensional conformational, intensity modulation, intracranial and extracranial stereotactic, image-guided, total body irradiation, hadron-therapy, and peri-operative radiotherapy. The last parts analyse the activity of radiotherapy centres in terms of treated patients, of patient age structure, of sessions and preparations, and of treated pathologies, the medical and paramedical personnel in charge of radiotherapy, and financial and cost aspects

  20. Ionizing radiation-induced DNA damage and repair as a potential biomarker in biodosimetry, cancer risk analysis and for prediction of radiotherapy induced toxicity

    International Nuclear Information System (INIS)

    Satish Rao, B.S.

    2017-01-01

    Lymphocytes isolated from peripheral blood from 100 healthy individuals, 232 cancer patients (cervical, breast cancer and head and neck cancer) irradiated in vitro or in vivo were used for measuring DNA damage and repair. The microscopic method of the γ-H2AX assay was adopted to elucidate the significance of DSB in biodosimetry, cancer risk susceptibility, and normal tissue toxicity prediction. We validated the use of H2AX assay in early triage biodosimetry by using lymphocytes from cervical cancer patients exposed to radiotherapy. Further, the basal and residual damage was significantly higher in cancer individuals compared to the healthy individuals. In cancer patients undergoing radiotherapy, we could able to show the increase in normal tissue toxicity with decreased DSB repair capacity. In conclusion this study indicates the DSB estimation by γ-H2AX foci analysis can serve as a tool to understand the triage of radiation exposed individuals, identifying individuals at cancer risk and normal tissue toxicity

  1. Systematic review of dose-volume parameters in the prediction of esophagitis in thoracic radiotherapy

    International Nuclear Information System (INIS)

    Rose, Jim; Rodrigues, George; Yaremko, Brian; Lock, Michael; D'Souza, David

    2009-01-01

    Purpose: With dose escalation and increasing use of concurrent chemoradiotherapy, radiation esophagitis (RE) remains a common treatment-limiting acute side effect in the treatment of thoracic malignancies. The advent of 3DCT planning has enabled investigators to study esophageal dose-volume histogram (DVH) parameters as predictors of RE. The purpose of this study was to assess published dosimetric parameters and toxicity data systematically in order to define reproducible predictors of RE, both for potential clinical use, and to provide recommendations for future research in the field. Materials and methods: We performed a systematic literature review of published studies addressing RE in the treatment of lung cancer and thymoma. Our search strategy included a variety of electronic medical databases, textbooks and bibliographies. Both prospective and retrospective clinical studies were included. Information relating to the relationship among measured dosimetric parameters, patient demographics, tumor characteristics, chemotherapy and RE was extracted and analyzed. Results: Eighteen published studies were suitable for analysis. Eleven of these assessed acute RE, while the remainder assessed both acute and chronic RE together. Heterogeneity of esophageal contouring practices, individual differences in information reporting and variability of RE outcome definitions were assessed. Well-described clinical and logistic modeling directly related V 35Gy , V 60Gy and SA 55Gy to clinically significant RE. Conclusions: Several reproducible dosimetric parameters exist in the literature, and these may be potentially relevant in the prediction of RE in the radiotherapy of thoracic malignancies. Further clarification of the predictive relationship between such standardized dosimetric parameters and observed RE outcomes is essential to develop efficient radiation treatment planning in locally advanced NSCLC in the modern concurrent chemotherapy and image-guided IMRT era.

  2. Dosimetry analysis on radiation-induced acute esophagitis after three-dimensional conformal radiotherapy for non-small cell lung cancer

    International Nuclear Information System (INIS)

    ZZhu Shuchai; Cui Yanli; Li Juan; Liu Zhikun; Shen Wenbin; Su Jingwei; Wang Yuxiang

    2010-01-01

    Objective: To analyze the related factors with radiation-induced esophagitis after threedimensional conformal radiotherapy for non-small cell lung cancer (NSCLC), in order to explore the predictors for optimizing the treatment planning of NSCLC. Methods: From Aug 2000 to Dec 2004, 104 NSCLC patients received radiotherapy and were eligible for this study, 45 cases squamous cell carcinoma, 20 cases adenocarcinoma, 33 cases carrying with cancer cells by test and 6 case with no definitive pathologic feature.46 patients were treated with three dimensional conformal radiotherapy (3DCRT), the other 58 patients conventional radiotherapy (CRT) before later-course 3DCRT. All the patients received the prescribed dose between 60-78 Gy and the median dose 66 Gy. The correlation of the variables were evaluated by Spearman relationship analysis. The morbidity of radiation-induced esophagitis was analyzed by X 2 test. The multivariate effect on radiation-induced esophagitis was statistically processed by Logistic regression model. Results: In 104 patients, the morbidity of radiation- induced esophagitis was 46.2%, including 32 cases at grade 1, 15 cases at grade 2, 1 case at grade 3. Univariate analysis showed the maximal and mean dose of esophagus, the volume of esophagus irradiated, the values of V 40 , V 45 , V 50 , V 55 , V 60 , LETT 45 , LETT 50 , LETT 55 , LETT 60 for the esophagus were correlated with radiation-induced esophagitis. Logistic regression model showed that the maximum dose received by the esophagus was the independent factor of ≥ 2 grade radiation-induced esophagitis. Conclusions: The maxmal dose of esophagus received might be the important factor of radiation-induced esophagitis. (authors)

  3. Combination of post-operative radiotherapy and cetuximab for high-risk cutaneous squamous cell cancer of the head and neck: A propensity score analysis.

    Science.gov (United States)

    Palmer, Joshua D; Schneider, Charles J; Hockstein, Neil; Hanlon, Alexandra L; Silberg, Jordan; Strasser, Jon; Mauer, Elizabeth A; Dzeda, Michael; Witt, Robert; Raben, Adam

    2018-03-01

    The objective of this study was to investigate the safety, tolerability and preliminary efficacy of radiotherapy plus cetuximab in high risk CSCC patients. Patients with high-risk CSCC diagnosed between 2006 and 2013 were analyzed. Patients were divided into two groups: radiotherapy alone versus radiotherapy plus cetuximab. Among 68 patients meeting study criteria, we identified 29 treated with cetuximab plus RT and 39 with RT alone. Primary analysis examined disease-free and overall survival, freedom from local and distant recurrence in the propensity score matched cohort. Propensity score analysis was performed with weighted factors including: Charlson Comorbidity Index score, age. KPS, primary location, T and N stage, recurrent status, margin status, LVSI, PNI and grade. Toxicity was assessed using the CTCAE v4.0. Median follow-up for living patients was 30 months. Patients in the cetuximab group were more likely to have advanced N stage, positive margins and recurrent disease. After propensity score matching the groups were well balanced. Six patients experienced ≥ grade 3 acute toxicity in the cetuximab group. The 1-year, 2-year and 5-year progression free survival (PFS) for patients in the cetuximab group were 86%, 72% and 66%, respectively. The 1-year, 2-year and 5-year overall survival (OS) for patients in the cetuximab group was 98%, 80% and 80%, respectively. Although limited by small numbers, the combination of cetuximab and radiotherapy in CSCC appears well tolerated there were more long-term survivors and less distant metastasis in the cetuximab group. These promising finding warrant further studies. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Survival Outcomes in Resected Extrahepatic Cholangiocarcinoma: Effect of Adjuvant Radiotherapy in a Surveillance, Epidemiology, and End Results Analysis

    International Nuclear Information System (INIS)

    Vern-Gross, Tamara Z.; Shivnani, Anand T.; Chen, Ke; Lee, Christopher M.; Tward, Jonathan D.; MacDonald, O. Kenneth; Crane, Christopher H.; Talamonti, Mark S.; Munoz, Louis L.; Small, William

    2011-01-01

    Purpose: The benefit of adjuvant radiotherapy (RT) after surgical resection for extrahepatic cholangiocarcinoma has not been clearly established. We analyzed survival outcomes of patients with resected extrahepatic cholangiocarcinoma and examined the effect of adjuvant RT. Methods and Materials: Data were obtained from the Surveillance, Epidemiology, and End Results (SEER) program between 1973 and 2003. The primary endpoint was the overall survival time. Cox regression analysis was used to perform univariate and multivariate analyses of the following clinical variables: age, year of diagnosis, histologic grade, localized (Stage T1-T2) vs. regional (Stage T3 or greater and/or node positive) stage, gender, race, and the use of adjuvant RT after surgical resection. Results: The records for 2,332 patients were obtained. Patients with previous malignancy, distant disease, incomplete or conflicting records, atypical histologic features, and those treated with preoperative/intraoperative RT were excluded. Of the remaining 1,491 patients eligible for analysis, 473 (32%) had undergone adjuvant RT. After a median follow-up of 27 months (among surviving patients), the median overall survival time for the entire cohort was 20 months. Patients with localized and regional disease had a median survival time of 33 and 18 months, respectively (p < .001). The addition of adjuvant RT was not associated with an improvement in overall or cause-specific survival for patients with local or regional disease. Conclusion: Patients with localized disease had significantly better overall survival than those with regional disease. Adjuvant RT was not associated with an improvement in long-term overall survival in patients with resected extrahepatic bile duct cancer. Key data, including margin status and the use of combined chemotherapy, was not available through the SEER database.

  5. Leukoencephalopathy in childhood hematopoietic neoplasm caused by moderate-dose methotrexate and prophylactic cranial radiotherapy -- an MR analysis

    International Nuclear Information System (INIS)

    Matsumoto, Ko; Takahashi, Shoki; Sato, Atsushi; Imaizumi, Masue; Higano, Shuichi; Sakamoto, Kiyohiko; Asakawa, Hiroshi; Tada, Keiya

    1995-01-01

    Purpose: The main purpose of this study was to determine influential factors related to minor leukoencephalopathy (LEP) caused by moderate-dose methotrexate (MTX) and prophylactic cranial radiotherapy (CRT) in childhood hematopoietic malignancies. We also compared the incidence of LEP following this treatment to that reported in the literature following treatment with high-dose MTX alone. Methods and Materials: Thirty-eight pediatric patients of hematopoietic malignancies (37 acute lymphoblastic leukemias, 1 non-Hodgkin lymphoma) who were given CRT (18-24 Gy) as well as prophylactic intrathecal and per os MTX were studied for leukoencephalopathy by magnetic resonance (MR) imaging. All the patients were free from grave neuropsychiatric disturbances. The data were examined to elucidate the influential ones of five factors (patients' age, doses of intrathecal and per os MTX, dose of CRT, interval between treatment, and MR study) to develop LEP using multiple regression analysis. To compare the effect of moderate-dose MTX and prophylactic CRT on LEP to that of high-dose MTX alone, we conducted literature review. Results: Seven out of 38 patients (18%) developed LEP. From multiple regression analysis and partial correlation coefficients, the age and CRT dose seemed influential in the subsequent development of LEP. The incidence of LEP following treatment with moderate-dose MTX and prophylactic CRT appears to be less than that reported in the literature following treatment with intravenous high-dose MTX. However, even moderate-dose MTX in combination with CRT can result in a significant incidence of MR-detectable LEP, particularly in children 6 years of age or younger receiving 24 Gy. Conclusion: Leukoencephalopathy was caused by moderate-dose MTX and prophylactic CRT in pediatric patients, probably less frequently than by high-dose MTX treatment alone. The influential factors were patient's age and CRT dose

  6. Is the time interval between surgery and radiotherapy important in operable nonsmall cell lung cancer? A retrospective analysis of 340 cases

    International Nuclear Information System (INIS)

    Wuerschmidt, Florian; Buenemann, Henry; Ehnert, Michael; Heilmann, Hans-Peter

    1997-01-01

    Purpose: To evaluate the influence of prognostic factors in postoperative radiotherapy of NSCLC with special emphasis on the time interval between surgery and start of radiotherapy. Methods and Materials: Between January 1976 and December 1993, 340 cases were treated and retrospectively analyzed meeting the following criteria: complete follow-up; complete staging information including pathological confirmation of resection status; maximum interval between surgery (SX) and radiotherapy (RT) of 12 weeks (median 36 days, range 18 to 84 days); minimum dose of 50 Gy (R0), and maximum dose of 70 Gy (R2). Two hundred thirty patients (68%) had N2 disease; 228 patients were completely resected (R0). One hundred six (31%) had adenocarcinoma, 172 (51%) squamous cell carcinoma. Results: In univariate analysis, Karnofsky performance status (90+ > 60-80%; p = 0.019 log rank), resection status stratified for nodal disease (R+ < R0; p = 0.046), and the time interval between SX and RT were of significant importance. Patients with a long interval (37 to 84 days) had higher 5-year survival rates (26%) and a median survival time (MST: 21.9 months, 95% C.I. 17.2 to 28.6 months) than patients with a short interval (18 to 36 days: 15%; 14.9 months, 13 to 19.9 months; p = 0.013). A further subgroup analysis revealed significant higher survival rates in patients with a long interval in N0/1 disease (p = 0.011) and incompletely resected NSCLC (p = 0.012). In multivariate analysis, the time interval had a p-value of 0.009 (nodal disease: p = 0.0083; KPI: p = 0.0037; sex: p = 0.035). Conclusion: Shortening the time interval between surgery and postoperative radiotherapy to less than 6 weeks even in R+ cases is not necessary. Survival of patients with a long interval between surgery and start of radiotherapy was better in this retrospective analysis as compared to patients with a short interval

  7. An accuracy analysis of Cyberknife tumor tracking radiotherapy according to unpredictable change of respiration

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Jung Min; Lee, Chang Yeol; Huh, Hyun Do; Kim, Wan Sun [Dept. of Radiation Oncology, Inha university hospital, Incheon (Korea, Republic of)

    2015-12-15

    Cyber-Knife tumor tracking system, based on the correlation relationship between the position of a tumor which moves in response to the real time respiratory cycle signal and respiration was obtained by the LED marker attached to the outside of the patient, the location of the tumor to predict in advance, the movement of the tumor in synchronization with the therapeutic device to track real-time tumor, is a system for treating. The purpose of this study, in the cyber knife tumor tracking radiation therapy, trying to evaluate the accuracy of tumor tracking radiation therapy system due to the change in the form of unpredictable sudden breathing due to cough and sleep. Materials and Methods : Breathing Log files that were used in the study, based on the Respiratory gating radiotherapy and Cyber-knife tracking radiosurgery breathing Log files of patients who received herein, measured using the Log files in the form of a Sinusoidal pattern and Sudden change pattern. it has been reconstituted as possible. Enter the reconstructed respiratory Log file cyber knife dynamic chest Phantom, so that it is possible to implement a motion due to respiration, add manufacturing the driving apparatus of the existing dynamic chest Phantom, Phantom the form of respiration we have developed a program that can be applied to. Movement of the phantom inside the target (Ball cube target) was driven by the displacement of three sizes of according to the size of the respiratory vertical (Superior-Inferior) direction to the 5 mm, 10 mm, 20 mm. Insert crosses two EBT3 films in phantom inside the target in response to changes in the target movement, the End-to-End (E2E) test provided in Cyber-Knife manufacturer depending on the form of the breathing five times each. It was determined by carrying. Accuracy of tumor tracking system is indicated by the target error by analyzing the inserted film, additional E2E test is analyzed by measuring the correlation error while being advanced. If the target

  8. An accuracy analysis of Cyberknife tumor tracking radiotherapy according to unpredictable change of respiration

    International Nuclear Information System (INIS)

    Seo, Jung Min; Lee, Chang Yeol; Huh, Hyun Do; Kim, Wan Sun

    2015-01-01

    Cyber-Knife tumor tracking system, based on the correlation relationship between the position of a tumor which moves in response to the real time respiratory cycle signal and respiration was obtained by the LED marker attached to the outside of the patient, the location of the tumor to predict in advance, the movement of the tumor in synchronization with the therapeutic device to track real-time tumor, is a system for treating. The purpose of this study, in the cyber knife tumor tracking radiation therapy, trying to evaluate the accuracy of tumor tracking radiation therapy system due to the change in the form of unpredictable sudden breathing due to cough and sleep. Materials and Methods : Breathing Log files that were used in the study, based on the Respiratory gating radiotherapy and Cyber-knife tracking radiosurgery breathing Log files of patients who received herein, measured using the Log files in the form of a Sinusoidal pattern and Sudden change pattern. it has been reconstituted as possible. Enter the reconstructed respiratory Log file cyber knife dynamic chest Phantom, so that it is possible to implement a motion due to respiration, add manufacturing the driving apparatus of the existing dynamic chest Phantom, Phantom the form of respiration we have developed a program that can be applied to. Movement of the phantom inside the target (Ball cube target) was driven by the displacement of three sizes of according to the size of the respiratory vertical (Superior-Inferior) direction to the 5 mm, 10 mm, 20 mm. Insert crosses two EBT3 films in phantom inside the target in response to changes in the target movement, the End-to-End (E2E) test provided in Cyber-Knife manufacturer depending on the form of the breathing five times each. It was determined by carrying. Accuracy of tumor tracking system is indicated by the target error by analyzing the inserted film, additional E2E test is analyzed by measuring the correlation error while being advanced. If the target

  9. Usefulness of a thermoplastic breast bra for breast cancer radiotherapy. A prospective analysis

    Energy Technology Data Exchange (ETDEWEB)

    Piroth, Marc D.; Holy, Richard [RWTH Aachen University Hospital, Department of Radiation Oncology, Aachen (Germany); HELIOS University Hospital Wuppertal, Witten/Herdecke University, Department of Radiation Oncology, Wuppertal (Germany); Petz, Dalma; Pinkawa, Michael; Eble, Michael J. [RWTH Aachen University Hospital, Department of Radiation Oncology, Aachen (Germany)

    2016-09-15

    Despite modern techniques, in some patients receiving whole breast radiotherapy (WBI) parts of the heart and the lung might receive doses which are nowadays considered relevant for the development of late morbidity. Our aim was to analyze the usefulness of a thermoplastic breast brassiere to reduce lung and heart doses. A total of 29 patients with left-sided and 16 patients with right-sided breast cancer treated with breast conserving surgery and WBI between 2012 and 2013 were included in a prospective study analyzing the effectiveness of a thermoplastic breast bra. WBI was performed using 3D tangential fields up to 50.4 Gy. Treatment planning was performed with and without bra. Several dosimetrical parameters were analyzed comparatively focusing on the heart and ipsilateral lung. For heart dose comparisons, subvolumes like the left anterior descending artery (LAD) and a defined apical region, so-called ''apical myocardial territory'' (AMT), were defined. By using the bra, the mean lung dose was reduced by 30.6 % (left-sided cancer) and 29.5 % (right-sided; p < 0.001). The V{sub 20Gy} for the left lung was reduced by 39.5 % (4.9 vs. 8.1 % of volume; p < 0.001). The mean and maximum heart doses were significantly lower (1.6 vs. 2.1 Gy and 30.7 vs. 39.3 Gy; p = 0.01 and p < 0.001), which also applies to the mean and maximum dose for the AMT (2.5 vs. 4.4 Gy and 31.0 vs. 47.2 Gy; p < 0.01 and p < 0.001). The mean and maximum dose for LAD was lower without reaching significance. No acute skin toxicities > grade 2 were observed. By using a thermoplastic breast bra, radiation doses to the heart and especially parts of the heart apex and ipsilateral lung can be significantly lowered without additional skin toxicity. (orig.) [German] Trotz moderner Techniken koennen bei manchen Patientinnen bei der Ganzbrustbestrahlung Areale des Herzens und der Lunge Dosen erhalten, die heute als relevant fuer Spaettoxizitaeten gelten. Ziel war es, den Nutzen eines

  10. Radiotherapy in bladder cancer

    International Nuclear Information System (INIS)

    Rozan, R.

    1992-01-01

    In 1992, the problem of the vesical radiotherapy is not resolved. The author presents the situation and the different techniques of radiotherapy in bladder cancers: external radiotherapy, only and associated with surgery, interstitial curietherapy and non-classical techniques as per operative radiotherapy, neutron therapy and concurrent radiotherapy with chemotherapy. In order to compare their efficiency, the five-year survival are given in all cases.(10 tabs)

  11. Comments on 'Reconsidering the definition of a dose-volume histogram'-dose-mass histogram (DMH) versus dose-volume histogram (DVH) for predicting radiation-induced pneumonitis

    International Nuclear Information System (INIS)

    Mavroidis, Panayiotis; Plataniotis, Georgios A; Gorka, Magdalena Adamus; Lind, Bengt K

    2006-01-01

    In a recently published paper (Nioutsikou et al 2005 Phys. Med. Biol. 50 L17) the authors showed that the use of the dose-mass histogram (DMH) concept is a more accurate descriptor of the dose delivered to lung than the traditionally used dose-volume histogram (DVH) concept. Furthermore, they state that if a functional imaging modality could also be registered to the anatomical imaging modality providing a functional weighting across the organ (functional mass) then the more general and realistic concept of the dose-functioning mass histogram (D[F]MH) could be an even more appropriate descriptor. The comments of the present letter to the editor are in line with the basic arguments of that work since their general conclusions appear to be supported by the comparison of the DMH and DVH concepts using radiobiological measures. In this study, it is examined whether the dose-mass histogram (DMH) concept deviated significantly from the widely used dose-volume histogram (DVH) concept regarding the expected lung complications and if there are clinical indications supporting these results. The problem was investigated theoretically by applying two hypothetical dose distributions (Gaussian and semi-Gaussian shaped) on two lungs of uniform and varying densities. The influence of the deviation between DVHs and DMHs on the treatment outcome was estimated by using the relative seriality and LKB models using the Gagliardi et al (2000 Int. J. Radiat. Oncol. Biol. Phys. 46 373) and Seppenwoolde et al (2003 Int. J. Radiat. Oncol. Biol. Phys. 55 724) parameter sets for radiation pneumonitis, respectively. Furthermore, the biological equivalent of their difference was estimated by the biologically effective uniform dose (D-bar) and equivalent uniform dose (EUD) concepts, respectively. It is shown that the relation between the DVHs and DMHs varies depending on the underlying cell density distribution and the applied dose distribution. However, the range of their deviation in terms of

  12. Impact of postoperative radiotherapy and HER2/new overexpression in salivary duct carcinoma. A monocentric clinicopathologic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Haderlein, Marlen; Semrau, Sabine; Lettmaier, Sebastian; Hecht, Markus; Fietkau, Rainer [University Hospital of Erlangen, Department of Radiation Oncology, Erlangen (Germany); Scherl, Claudia; Iro, Heinrich [University Hospital of Erlangen, Department of Otorhinolaryngology, Erlangen (Germany); Erber, Ramona; Agaimy, Abbas [University Hospital of Erlangen, Institute of Pathology, Erlangen (Germany)

    2017-11-15

    Retrospective Investigation of the prognostic relevance of clinicopathologic parameters in patients with salivary duct carcinoma (SDC). An experienced pathologist reviewed 67 patients with de novo SDC or SDC ex pleomorphic adenoma. Paraffin-embedded tumor samples were examined by immunohistochemistry for expression of HER2/neu, androgen (AR), progesterone (PR), estrogen (ER), epidermal growth factor (EGFR) and programmed death ligand 1 (PD-L1-R) receptor. In 45 patients who had cM0 and follow-up data available, survival rates were calculated (Kaplan-Meier method) and prognostic variables were analyzed (univariate analysis: log-rank test; multivariate analysis: Cox-regression analysis). Overexpression of HER2/neu, AR, ER, PR, EGFR, PD-L1-R was found in 25.4%, 84%, 0%, 0%, 17.9%, 16.4% of patients. Overall (OS), disease-free (DFS), distant-metastases-free survival (DMFS) and locoregional control (LRC) were 92.3/72.4/56.9%, 78.2/58.1/58.1%, 85.4/65.2/65.2% and 89.7/81.9/81.9% after 1/3/5 years (medial follow-up 26 months). In univariate analysis a positive resection margin (p = 0.008) and no postoperative radiotherapy (p = 0.001) predict an increased locoregional recurrence rate. In multivariate analysis only postoperative radiotherapy is statistically significant (p = 0.004). Presence of lymph node metastases, a lymph node density >4 and HER2/neu overexpression predict decreased DFS and DMFS. In multivariate HER2/neu overexpression was the only significant predictor for reduced DFS (p = 0.04) and DMFS (p = 0.02). Postoperative radiotherapy is the only significant predictor for LRC. HER2/neu receptor expression is an independent prognostic factor for decreased DFS and DMFS in patients with SDC. In addition to radio(chemo)therapy, intensified first-line treatment regimens should also be evaluated in the future. (orig.) [German] In dieser retrospektiven Auswertung wurde der Einfluss klinisch-pathologischer Parameter auf die Prognose von Patienten mit

  13. Role of Radiotherapy in the Treatment of Cervical Lymph Node Metastases From an Unknown Primary Site: Retrospective Analysis of 113 Patients

    International Nuclear Information System (INIS)

    Beldi, Debora; Jereczek-Fossa, Barbara A.; D'Onofrio, Alberto; Gambaro, Giuseppina; Fiore, Maria Rosaria; Pia, Francesco; Chiesa, Fausto; Orecchia, Roberto; Krengli, Marco

    2007-01-01

    Purpose: The management of patients with cervical lymph-node metastases from unknown primary site (UPS) remains a matter of discussion. This study aimed to analyze the results and prognostic factors in a series of patients treated with radiotherapy. Methods and Materials: Data from 113 patients who presented with cervical lymph nodes metastases from UPS treated from 1980 to 2004 were reviewed. Eighty-seven patients (77.0%) were squamous cell carcinoma (SCC). Ninety-one patients were treated with curative and 22 with palliative intent. Fifty-nine of 113 patients (52.2%) received surgery followed by radiotherapy and 54 of 113 (47.8%) received radiotherapy alone. Radiotherapy was delivered to the neck and pharyngeal mucosa in 67 patients and to the ipsilateral or bilateral neck in 45 patients. Twenty-one patients (18.5%) also received chemotherapy. Results: The 5-year overall survival rates were 40.7% for the entire group and 46.6% for the SCC subgroup. The occurrence of the occult primary was observed in 23 of 113 patients (20.3%), 19 (82.6%) within the head and neck region. At multivariate analysis, treatment with curative intent and extensive irradiation of bilateral neck and pharyngeal mucosa were favorable prognostic factors for the whole series, and treatment with curative intent, extensive irradiation of bilateral neck and pharyngeal mucosa, and absence of extracapsular spread were favorable prognostic factors for the SCC subgroup. Conclusions: Patients with cervical lymph node metastases from UPS have a similar prognosis to those affected by other head and neck malignancies. Curative treatment strategies including neck dissection and extensive irradiation by three-dimensional conformal radiation therapy resulted in significantly better outcomes

  14. SU-E-J-265: Feasibility Study of Texture Analysis for Prognosis of Local Tumor Recurrence Within 5-Years for Pharyngeal-Laryngeal Carcinoma Patients Received Radiotherapy Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Huang, W; Tu, S [Chang Gung University, Kwei-shan, Tao-Yuan, Taiwan (China)

    2015-06-15

    Purpose: Pharyngeal and laryngeal carcinomas (PLC) are among the top leading cancers in Asian populations. Typically the tumor may recur and progress in a short period of time if radiotherapy fails to deliver a successful treatment. Here we used image texture features extracted from images of computed tomography (CT) planning and conducted a retrospective study to evaluate whether texture analysis is a feasible approach to predict local tumor recurrence for PLC patients received radiotherapy treatment. Methods: CT planning images of 100 patients with PLC treated by radiotherapy at our facility between 2001 and 2010 are collected. These patients were received two separate CT scans, before and mid-course of the treatment delivery. Before the radiotherapy, a CT scanning was used for the first treatment planning. A total of 30 fractions were used in the treatment and patients were scanned with a second CT around the end of the fifteenth delivery for an adaptive treatment planning. Only patients who were treated with intensity modulated radiation therapy and RapidArc were selected. Treatment planning software of Eclipse was used. The changes of texture parameters between two CT acquisitions were computed to determine whether they were correlated to the local tumor recurrence. The following texture parameters were used in the preliminary assessment: mean, variance, standard deviation, skewness, kurtosis, energy, entropy, inverse difference moment, cluster shade, inertia, cluster prominence, gray-level co-occurrence matrix, and gray-level run-length matrix. The study was reviewed and approved by the committee of our institutional review board. Results: Our calculations suggested the following texture parameters were correlated with the local tumor recurrence: skewness, kurtosis, entropy, and inertia (p<0.0.05). Conclusion: The preliminary results were positive. However some works remain crucial to be completed, including addition of texture parameters for different image

  15. Pharmacokinetic analysis and k-means clustering of DCEMR images for radiotherapy outcome prediction of advanced cervical cancers.

    Science.gov (United States)

    Andersen, Erlend K F; Kristensen, Gunnar B; Lyng, Heidi; Malinen, Eirik

    2011-08-01

    Pharmacokinetic analysis of dynamic contrast enhanced magnetic resonance images (DCEMRI) allows for quantitative characterization of vascular properties of tumors. The aim of this study is twofold, first to determine if tumor regions with similar vascularization could be labeled by clustering methods, second to determine if the identified regions can be associated with local cancer relapse. Eighty-one patients with locally advanced cervical cancer treated with chemoradiotherapy underwent DCEMRI with Gd-DTPA prior to external beam radiotherapy. The median follow-up time after treatment was four years, in which nine patients had primary tumor relapse. By fitting a pharmacokinetic two-compartment model function to the temporal contrast enhancement in the tumor, two pharmacokinetic parameters, K(trans) and ύ(e), were estimated voxel by voxel from the DCEMR-images. Intratumoral regions with similar vascularization were identified by k-means clustering of the two pharmacokinetic parameter estimates over all patients. The volume fraction of each cluster was used to evaluate the prognostic value of the clusters. Three clusters provided a sufficient reduction of the cluster variance to label different vascular properties within the tumors. The corresponding median volume fraction of each cluster was 38%, 46% and 10%. The second cluster was significantly associated with primary tumor control in a log-rank survival test (p-value: 0.042), showing a decreased risk of treatment failure for patients with high volume fraction of voxels. Intratumoral regions showing similar vascular properties could successfully be labeled in three distinct clusters and the volume fraction of one cluster region was associated with primary tumor control.

  16. Pharmacokinetic analysis and k-means clustering of DCEMR images for radiotherapy outcome prediction of advanced cervical cancers

    International Nuclear Information System (INIS)

    Andersen, Erlend K. F.; Kristensen, Gunnar B.; Lyng, Heidi; Malinen, Eirik

    2011-01-01

    Introduction. Pharmacokinetic analysis of dynamic contrast enhanced magnetic resonance images (DCEMRI) allows for quantitative characterization of vascular properties of tumors. The aim of this study is twofold, first to determine if tumor regions with similar vascularization could be labeled by clustering methods, second to determine if the identified regions can be associated with local cancer relapse. Materials and methods. Eighty-one patients with locally advanced cervical cancer treated with chemoradiotherapy underwent DCEMRI with Gd-DTPA prior to external beam radiotherapy. The median follow-up time after treatment was four years, in which nine patients had primary tumor relapse. By fitting a pharmacokinetic two-compartment model function to the temporal contrast enhancement in the tumor, two pharmacokinetic parameters, K trans and u e , were estimated voxel by voxel from the DCEMR-images. Intratumoral regions with similar vascularization were identified by k-means clustering of the two pharmacokinetic parameter estimates over all patients. The volume fraction of each cluster was used to evaluate the prognostic value of the clusters. Results. Three clusters provided a sufficient reduction of the cluster variance to label different vascular properties within the tumors. The corresponding median volume fraction of each cluster was 38%, 46% and 10%. The second cluster was significantly associated with primary tumor control in a log-rank survival test (p-value: 0.042), showing a decreased risk of treatment failure for patients with high volume fraction of voxels. Conclusions. Intratumoral regions showing similar vascular properties could successfully be labeled in three distinct clusters and the volume fraction of one cluster region was associated with primary tumor control

  17. Matched Cohort Analysis of Outcomes of Definitive Radiotherapy for Prostate Cancer in Human Immunodeficiency Virus-Positive Patients

    International Nuclear Information System (INIS)

    Kahn, Shannon; Jani, Ashesh; Edelman, Scott; Rossi, Peter; Godette, Karen; Landry, Jerome; Anderson, Cynthia

    2012-01-01

    Purpose: To compare the biochemical outcome and toxicity scores of men with human immunodeficiency virus (HIV) and prostate cancer with a matched control population with negative or unknown HIV status when treated with external-beam radiotherapy (EBRT). Methods and Materials: A single-institution database of men with prostate cancer treated with EBRT from 1999 to 2009 was reviewed. Thirteen men with HIV were identified and matched to 2 control patients according to age, race, T stage, prostate-specific antigen level, Gleason score, RT dose, intensity-modulated RT vs. three-dimensional conformal RT, and whole-pelvis vs. prostate-only RT, for a total of 39 cases. The median follow-up time was 39 months (range, 3–110 months). Results: The 4-year biochemical failure (BF)-free survival rate was 87% in the HIV-positive group vs. 89% in the controls (p = 0.94). Pre- and post-RT viral loads were found to be predictive of BF (p = 0.04 and p = 0.04, respectively). No men with HIV died, whereas 2 in the control group died of causes unrelated to prostate cancer. Acute and chronic genitourinary and gastrointestinal toxicity were less in the HIV-positive patients than in controls (p 3 . Conclusions: Our findings suggest that men with HIV treated with EBRT have a similar risk of BF; however, high viral loads may contribute to an increased risk. This analysis supports that HIV-positive men with prostate cancer can be treated with definitive EBRT with similar disease control and toxicity outcomes as in the general population.

  18. Pharmacokinetic analysis and k-means clustering of DCEMR images for radiotherapy outcome prediction of advanced cervical cancers

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, Erlend K. F. (Dept. of Medical Physics, The Norwegian Radium Hospital, Oslo Univ. Hospital, Oslo (Norway)), e-mail: eirik.malinen@fys.uio.no; Kristensen, Gunnar B. (Section for Gynaecological Oncology, The Norwegian Radium Hospital, Oslo Univ. Hospital, Oslo (Norway)); Lyng, Heidi (Dept. of Radiation Biology, The Norwegian Radium Hospital, Oslo Univ. Hospital, Oslo (Norway)); Malinen, Eirik (Dept. of Medical Physics, The Norwegian Radium Hospital, Oslo Univ. Hospital, Oslo (Norway); Dept. of Physics, Univ. of Oslo, Oslo (Norway))

    2011-08-15

    Introduction. Pharmacokinetic analysis of dynamic contrast enhanced magnetic resonance images (DCEMRI) allows for quantitative characterization of vascular properties of tumors. The aim of this study is twofold, first to determine if tumor regions with similar vascularization could be labeled by clustering methods, second to determine if the identified regions can be associated with local cancer relapse. Materials and methods. Eighty-one patients with locally advanced cervical cancer treated with chemoradiotherapy underwent DCEMRI with Gd-DTPA prior to external beam radiotherapy. The median follow-up time after treatment was four years, in which nine patients had primary tumor relapse. By fitting a pharmacokinetic two-compartment model function to the temporal contrast enhancement in the tumor, two pharmacokinetic parameters, Ktrans and u{sub e}, were estimated voxel by voxel from the DCEMR-images. Intratumoral regions with similar vascularization were identified by k-means clustering of the two pharmacokinetic parameter estimates over all patients. The volume fraction of each cluster was used to evaluate the prognostic value of the clusters. Results. Three clusters provided a sufficient reduction of the cluster variance to label different vascular properties within the tumors. The corresponding median volume fraction of each cluster was 38%, 46% and 10%. The second cluster was significantly associated with primary tumor control in a log-rank survival test (p-value: 0.042), showing a decreased risk of treatment failure for patients with high volume fraction of voxels. Conclusions. Intratumoral regions showing similar vascular properties could successfully be labeled in three distinct clusters and the volume fraction of one cluster region was associated with primary tumor control

  19. Matched Cohort Analysis of Outcomes of Definitive Radiotherapy for Prostate Cancer in Human Immunodeficiency Virus-Positive Patients

    Energy Technology Data Exchange (ETDEWEB)

    Kahn, Shannon, E-mail: shannonkahn@yahoo.com [Department of Radiation Oncology, Emory University School of Medicine, Atlanta, GA (United States); Jani, Ashesh; Edelman, Scott; Rossi, Peter; Godette, Karen; Landry, Jerome; Anderson, Cynthia [Department of Radiation Oncology, Emory University School of Medicine, Atlanta, GA (United States); Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA (United States)

    2012-05-01

    Purpose: To compare the biochemical outcome and toxicity scores of men with human immunodeficiency virus (HIV) and prostate cancer with a matched control population with negative or unknown HIV status when treated with external-beam radiotherapy (EBRT). Methods and Materials: A single-institution database of men with prostate cancer treated with EBRT from 1999 to 2009 was reviewed. Thirteen men with HIV were identified and matched to 2 control patients according to age, race, T stage, prostate-specific antigen level, Gleason score, RT dose, intensity-modulated RT vs. three-dimensional conformal RT, and whole-pelvis vs. prostate-only RT, for a total of 39 cases. The median follow-up time was 39 months (range, 3-110 months). Results: The 4-year biochemical failure (BF)-free survival rate was 87% in the HIV-positive group vs. 89% in the controls (p = 0.94). Pre- and post-RT viral loads were found to be predictive of BF (p = 0.04 and p = 0.04, respectively). No men with HIV died, whereas 2 in the control group died of causes unrelated to prostate cancer. Acute and chronic genitourinary and gastrointestinal toxicity were less in the HIV-positive patients than in controls (p < 0.001, p < 0.001, p = 0.003, and p < 0.001, respectively). The HIV-positive men experienced an average decline in CD4 count of 193 cells/mm{sup 3}. Conclusions: Our findings suggest that men with HIV treated with EBRT have a similar risk of BF; however, high viral loads may contribute to an increased risk. This analysis supports that HIV-positive men with prostate cancer can be treated with definitive EBRT with similar disease control and toxicity outcomes as in the general population.

  20. Qualitative risk analysis in the process of treatment in radiation oncology for the steps performed by the technician/technologist in intensity modulated radiotherapy (lMRT)

    International Nuclear Information System (INIS)

    Teixeira, Flavia C.S.; Faria, Alessandra L.; Pereira, Danielle P.S.; Silva, Fabiana M.I.

    2013-01-01

    The efficacy of radiation therapy is to eradicate the tumor while preserving the integrity of normal tissues. Technological advances have allowed to develop techniques capable of modulating doses delivered to the target volume, providing more effective treatments. However, the operational complexity of these techniques makes the benefits offered are directly proportional to the chances of occurrences of serious errors. The objective of this work is to analyze the steps performed by the technician/technologist in Intensity Modulated Radiotherapy (IMRT), to detect possible errors in order to determine ways to mitigate them. After literature regarding errors in the radiation therapy, a prospective analysis was performed in the first half of 2012 in a radiation clinic located in the city of Rio de Janeiro, in which 11 technicians/technologists contributed to the survey data analysis. The method of risk analysis Failure Mode and Effects Analysis was used for prospective analysis of accidents/incidents, with respect to a qualitative assessment . The method allowed mapping 16 steps performed by technicians/technologists in the treatments with IMRT, identifying possible failures and their causes allowing to find ways to avoid possible errors. This analysis helped to confirm that the qualification and continuing education of technicians/technologists, allied to implement quality assurance programs and a computerized management can make a tool capable of IMRT to achieve the greatest challenge of radiotherapy. (author)

  1. Parotid gland sparing radiotherapy technique using 3-D conformal radiotherapy for nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Lim, Ji Hoon; Kim, Gwi Eon; Keum, Ki Chang; Suh, Chang Ok; Lee, Sang Wook; Park, Hee Chul; Cho, Jae Ho; Chang, Sei Kyung; Loh, Juhn Kyu

    2000-01-01

    Although using the high energy photon beam with conventional parallel-opposed beams radio-therapy for nasopgaryngeal carcinoma, radiation-induced xerostomia is a troublesome problem for patients. We conducted this study to explore a new parotid gland sparing technique in 3-D conformal radiotherapy (3-DCRT) in an effort to prevent the radiation-induced xerostomia. We performed three different planning for four clinically node-negative nasopharyngeal cancer patients with different location of tumor(intracranial extension, nasal cavity extension, oropharyngeal extension, parapharyngeal extension), and intercompared the plans. Total prescription dose was 70.2 Gy to the isocenter. For plan-A, 2-D parallel opposing fields, a conventional radiotherapy technique, were employed. For plan-B, 2-D parallel opposing fields were used up until 54 Gy and afterwards 3-D non-coplanar beams were used. For plan-C, the new technique, 54Gy was delivered by 3-D conformal 3-port beams (AP and both lateral ports with wedge compensator, shielding both superficial lobes of parotid glands at the AP beam using BEV) from the beginning of the treatment and early spinal cord block (at 36 Gy) was performed. And bilateral posterior necks were treated with electron after 36 Gy. After 54 Gy, non-coplanar beams were used for cone-down plan. We intercompared dose statistics (Dmax, Dmin, Dmean, D95, D05, V95, V05, Volume receiving 46 Gy) and dose volume histograms (DVH) of tumor and normal tissues and NTCP values of parotid glands for the above three plans. For all patients, the new technique (plan-C) was comparable or superior to the other plans in target volume isodose distribution and dose statistics and it has more homogenous target volume coverage. The new technique was most superior to the other plans in parotid glands sparing (volume receiving 46 Gy: 100, 98, 69% for each plan-A, B and C). And it showed the lowest NTCP value of parotid glands in all patients (range of NTCP; 96-100%, 79-99%, 51

  2. Visual Analysis of Tumor Control Models for Prediction of Radiotherapy Response

    DEFF Research Database (Denmark)

    Raidou, Renata G.; Casares Magaz, Oscar; Muren, Ludvig

    2016-01-01

    on TCP modeling, to explore the information provided by their models, to discover new knowledge and to confirm or generate hypotheses within their data. Our approach incorporates the following four main components: (1) It supports the exploration of uncertainty and its effect on TCP models; (2...... impact on the modeling outcome, while the models are sensitive to a number of parameter assumptions. Currently, uncertainty and parameter sensitivity are not incorporated in the analysis, due to time and resource constraints. To this end, we propose a visual tool that enables clinical researchers working......) It facilitates parameter sensitivity anal- ysis to common assumptions; (3) It enables the identification of inter-patient response variability; (4) It allows starting the analysis from the desired treatment outcome, to identify treatment strategies that achieve it. We con- ducted an evaluation with nine clinical...

  3. Preliminary analysis of the risk factors for radiation pneumonitis in patients with non- small-cell lung cancer treated with concurrent erlotinib and thoracic radiotherapy

    Directory of Open Access Journals (Sweden)

    Zhuang H

    2014-05-01

    Full Text Available Hongqing Zhuang,* Hailing Hou,* Zhiyong Yuan, Jun Wang, Qingsong Pang, Lujun Zhao, Ping WangDepartment of Radiotherapy, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin Key Laboratory of Cancer Prevention and Therapy, and Tianjin Lung Cancer Center, Tianjin, People's Republic of China*These authors contributed equally to this workPurpose: The aim of this study was to investigate radiation pneumonitis and its associated risk factors in patients with non-small-cell lung cancer treated with concurrent erlotinib and thoracic radiotherapy.Materials and methods: We conducted an analysis of patients with nonoperable stage IIIA–IV non-small-cell lung cancer who were treated with concurrent thoracic radiotherapy and erlotinib (ClinicalTrials.gov identifier: NCT00973310. The Common Terminology Criteria for Adverse Events version 3.0 grading system was applied to evaluate the incidence of radiation pneumonitis. The lung dosimetric parameters were recorded in accordance with the treatment plan, and the study endpoint was radiation pneumonitis at grade 2 or more.Results: Among the 24 selected clinical cases, nine were identified with radiation pneumonitis of grade 2 or above (37.5%. This included four cases with grade 2 (16.7%, two cases with grade 3 (8.3%, and three cases with grade 5 (12.5%. The results showed that the planning target volume was a significant factor affecting the incidence of radiation pneumonitis. All lung dosimetric parameters exhibited statistically significant differences between patients with pneumonitis and patients without pneumonitis. The receiver operating characteristic (ROC curve analysis showed that all lung dosimetric parameters were useful in predicting the incidence of radiation pneumonitis. In addition, the threshold values of V5, V10, V15, V20, V30, and mean lung dose were >4%, >29%, >27%, >22%, >17% and >1,027 cGy, respectively.Conclusion: Special attention

  4. Radiotherapy of bronchogenic carcinoma

    International Nuclear Information System (INIS)

    Heilmann, H.P.

    1982-01-01

    Radiotherapy of branchogenic carcinoma comprises; palliative treatment, postoperative or pre-operative radiotherapy, radiotherapy as part of a combination of chemotherapy and radiotherapy of small cell carcinoma and curative radiotherapy of non-operable non-small cell carcinoma. Atelectasis and obstruction are indications for palliative radiotherapy. Postoperative radiotherapy is given only in cases of incomplete resection or mediastinal metastases. In the treatment of small cell carcinoma by combined irradiation and chemotherapy the mediastinum and primary tumour are irradiated, generally after chemotherapy, and the C.N.S. receives prophylactic radiotherapy. Curative radiotherapy is indicated in cases of non-operable small cell carcinoma. Irradiation with doses of 60-70 Gy produced 5-years-survival rates of 10-14% in cases classified as T 1 -T 2 N 0 M 0 . (orig.) [de

  5. WE-H-BRC-02: Failure Mode and Effect Analysis of Liver Stereotactic Body Radiotherapy

    International Nuclear Information System (INIS)

    Rusu, I; Thomas, T; Roeske, J; Price, J; Perino, C; Surucu, M; Mescioglu, I

    2016-01-01

    Purpose: To identify areas of improvement in our liver stereotactic body radiation therapy (SBRT) program, using failure mode and effect analysis (FMEA). Methods: A multidisciplinary group consisting of one physician, three physicists, one dosimetrist and two therapists was formed. A process map covering 10 major stages of the liver SBRT program from the initial diagnosis to post treatment follow-up was generated. A total of 102 failure modes, together with their causes and effects, were identified. The occurrence (O), severity (S) and lack of detectability (D) were independently scored. The ranking was done using the risk probability number (RPN) defined as the product of average O, S and D numbers for each mode. The scores were normalized to remove inter-observer variability, while preserving individual ranking order. Further, a correlation analysis on the overall agreement on rank order of all failure modes resulted in positive values for successive pairs of evaluators. The failure modes with the highest RPN value were considered for further investigation. Results: The average normalized RPN values for all modes were 39 with a range of 9 to 103. The FMEA analysis resulted in the identification of the top 10 critical failures modes as: Incorrect CT-MR registration, MR scan not performed in treatment position, patient movement between CBCT acquisition and treatment, daily IGRT QA not verified, incorrect or incomplete ITV delineation, OAR contours not verified, inaccurate normal liver effective dose (Veff) calculation, failure of bolus tracking for 4D CT scan, setup instructions not followed for treatment and plan evaluation metrics missed. Conclusion: The application of FMEA to our liver SBRT program led to the identification and possible improvement of areas affecting patient safety.

  6. WE-H-BRC-02: Failure Mode and Effect Analysis of Liver Stereotactic Body Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Rusu, I; Thomas, T; Roeske, J; Price, J; Perino, C; Surucu, M [Loyola University Chicago, Maywood, IL (United States); Mescioglu, I [Lewis University, Romeoville, IL (United States)

    2016-06-15

    Purpose: To identify areas of improvement in our liver stereotactic body radiation therapy (SBRT) program, using failure mode and effect analysis (FMEA). Methods: A multidisciplinary group consisting of one physician, three physicists, one dosimetrist and two therapists was formed. A process map covering 10 major stages of the liver SBRT program from the initial diagnosis to post treatment follow-up was generated. A total of 102 failure modes, together with their causes and effects, were identified. The occurrence (O), severity (S) and lack of detectability (D) were independently scored. The ranking was done using the risk probability number (RPN) defined as the product of average O, S and D numbers for each mode. The scores were normalized to remove inter-observer variability, while preserving individual ranking order. Further, a correlation analysis on the overall agreement on rank order of all failure modes resulted in positive values for successive pairs of evaluators. The failure modes with the highest RPN value were considered for further investigation. Results: The average normalized RPN values for all modes were 39 with a range of 9 to 103. The FMEA analysis resulted in the identification of the top 10 critical failures modes as: Incorrect CT-MR registration, MR scan not performed in treatment position, patient movement between CBCT acquisition and treatment, daily IGRT QA not verified, incorrect or incomplete ITV delineation, OAR contours not verified, inaccurate normal liver effective dose (Veff) calculation, failure of bolus tracking for 4D CT scan, setup instructions not followed for treatment and plan evaluation metrics missed. Conclusion: The application of FMEA to our liver SBRT program led to the identification and possible improvement of areas affecting patient safety.

  7. Late rectal toxicity after conformal radiotherapy of prostate cancer (I): multivariate analysis and dose-response

    International Nuclear Information System (INIS)

    Skwarchuk, Mark W.; Jackson, Andrew; Zelefsky, Michael J.; Venkatraman, Ennapadam S.; Cowen, Didier M.; Levegruen, Sabine; Burman, Chandra M.; Fuks, Zvi; Leibel, Steven A.; Ling, C. Clifton

    2000-01-01

    Purpose: The purpose of this paper is to use the outcome of a dose escalation protocol for three-dimensional conformal radiation therapy (3D-CRT) of prostate cancer to study the dose-response for late rectal toxicity and to identify anatomic, dosimetric, and clinical factors that correlate with late rectal bleeding in multivariate analysis. Methods and Materials: Seven hundred forty-three patients with T1c-T3 prostate cancer were treated with 3D-CRT with prescribed doses of 64.8 to 81.0 Gy. The 5-year actuarial rate of late rectal toxicity was assessed using Kaplan-Meier statistics. A retrospective dosimetric analysis was performed for patients treated to 70.2 Gy (52 patients) or 75.6 Gy (119 patients) who either exhibited late rectal bleeding (RTOG Grade 2/3) within 30 months after treatment (i.e., 70.2 Gy--13 patients, 75.6 Gy--36 patients) or were nonbleeding for at least 30 months (i.e., 70.2 Gy--39 patients, 75.6 Gy--83 patients). Univariate and multivariate logistic regression was performed to correlate late rectal bleeding with several anatomic, dosimetric, and clinical variables. Results: A dose response for ≥ Grade 2 late rectal toxicity was observed. By multivariate analysis, the following factors were significantly correlated with ≥ Grade 2 late rectal bleeding for patients prescribed 70.2 Gy: 1) enclosure of the outer rectal contour by the 50% isodose on the isocenter slice (i.e., Iso50) (p max (p max

  8. How many new cancer patients in Europe will require radiotherapy by 2025? An ESTRO-HERO analysis

    DEFF Research Database (Denmark)

    Borras, Josep M; Lievens, Yolande; Barton, Michael

    2016-01-01

    BACKGROUND: The objective of this HERO study was to assess the number of new cancer patients that will require at least one course of radiotherapy by 2025. METHODS: European cancer incidence data by tumor site and country for 2012 and 2025 was extracted from the GLOBOCAN database. The projection ...

  9. Imaging analysis of heart movement for improving the respiration-gated radiotherapy in patients with left sided breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Abdelhamid, Rania; Farrag, A.; Khalifa, A. [Clinical Oncology Department, Assiut University (Egypt); Block, Andreas [Institut fuer Medizinische Strahlenphysik und Strahlenschutz, Klinikum Dortmund (Germany)

    2012-07-01

    Respiration induced heart movement during radiotherapy exposes the heart to the inevitable risks of radio-exposure, and hence radiation injury, in cases of Lt. sided breast cancer. The impact of such a risk is additionally aggravated by the use of radiotherapy in combination with cardiotoxic chemotherapeutic agents. Radio-oncologists pay special attention to the coronary arteries that might be included in this small part of the heart exposed to radiation. The aim of this study was to include the internal heart movement for improving respiration-gated radiotherapy of left sided breast cancer. For 70 patients, all females left sided breast cancer, two planning CT's in inspiration and expiration, and one free breathing scan are performed. The heart motion was analyzed with the clinic-developed software ORAT in the simulator sequence for acquiring information of the cranio-caudal amplitude of heart movements in free breathing (respiration-induced amplitude) and a 15 seconds breath-hold phase (inherent amplitude). The role of inherent heart movement varies from one patient to another which should be taken in consideration during defining the parameters of respiration-gated radiotherapy. The inherent amplitude of the heart motion is the physiological lower limit of the respiration-gating window.

  10. How many new cancer patients in Europe will require radiotherapy by 2025? An ESTRO-HERO analysis.

    Science.gov (United States)

    Borras, Josep M; Lievens, Yolande; Barton, Michael; Corral, Julieta; Ferlay, Jacques; Bray, Freddie; Grau, Cai

    2016-04-01

    The objective of this HERO study was to assess the number of new cancer patients that will require at least one course of radiotherapy by 2025. European cancer incidence data by tumor site and country for 2012 and 2025 was extracted from the GLOBOCAN database. The projection of the number of new cases took into account demographic factors (age and size of the population). Population based stages at diagnosis were taken from four European countries. Incidence and stage data were introduced in the Australian Collaboration for Cancer Outcomes Research and Evaluation (CCORE) model. Among the different tumor sites, the highest expected relative increase by 2025 in treatment courses was prostate cancer (24%) while lymphoma (13%), head and neck (12%) and breast cancer (10%) were below the average. Based on the projected cancer distributions in 2025, a 16% expected increase in the number of radiotherapy treatment courses was estimated. This increase varied across European countries from less than 5% to more than 30%. With the already existing disparity in radiotherapy resources in mind, the data provided here should act as a leverage point to raise awareness among European health policy makers of the need for investment in radiotherapy. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  11. Analysis of the frequency and degree of temporomandibular disorder in patients with head and neck cancer undergoing radiotherapy

    Directory of Open Access Journals (Sweden)

    Douglas Roberto Pegoraro

    Full Text Available Abstract Introduction: Head and neck cancer is responsible for an increasing incidence of primary malignant neoplasm cases worldwide. Radiotherapy is one of the treatments of choice for this type of cancer, but it can cause adverse effects, such as temporomandibular disorder. The objective of this study was to characterize the degree and frequency of temporomandibular disorder in patients with head and neck cancer undergoing radiotherapy. Method: This research was quantitative, descriptive and exploratory. The sample consisted of 22 patients that answered assessment questions and the Helkimo anamnestic questionnaire, modified by Fonseca (1992. The data were collected from May to October 2014, and statistically analyzed using the Chi-square test, with a significance level of p ≤ 0.05. Results: Of the 22 patients, 86.4 % were male, with a mean age of 58.86 ± 9.41 years. Temporomandibular disorder was present in 31.8% of the subjects, based on the assessment prior to radiotherapy, and in 59.1% in the post-treatment assessment. Among all questions, the most frequent was "Do you use only one side of the mouth to chew?" with 22.7% "yes" answers, both at the first assessment and at the post treatment. Conclusion: According to the results of this study, temporomandibular disorder is a disease that is present with a high prevalence in people diagnosed with head and neck cancer undergoing radiotherapy.

  12. Radiotherapy for carcinoma of the vagina. Immunocytochemical and cytofluorometric analysis of prognostic factors

    Energy Technology Data Exchange (ETDEWEB)

    Blecharz, P. [Maria Sklodowska-Curie Memorial Institute, Krakow (Poland). Dept. of Gynecological Oncology; Reinfuss, M.; Jakubowicz, J. [Maria Sklodowska-Curie Memorial Institute, Krakow (Poland). Dept. of Radiation Oncology; Rys, J. [Maria Sklodowska-Curie Memorial Institute, Krakow (Poland). Dept. of Tumor Pathology Oncology; Skotnicki, P.; Wysocki, W. [Maria Sklodowska-Curie Memorial Institute, Krakow (Poland). Dept. of Oncological Surgery

    2013-05-15

    Background and purpose: The aim of this study was to assess the potential prognostic factors in patients with primary invasive vaginal carcinoma (PIVC) treated with radical irradiation. Patients and methods: The analysis was performed on 77 patients with PIVC treated between 1985 and 2005 in the Maria Sklodowska-Curie Memorial Institute of Oncology, Cancer Center in Krakow. A total of 36 patients (46.8 %) survived 5 years with no evidence of disease (NED). The following groups of factors were assessed for potential prognostic value: population-based (age), clinical (Karnofsky Performance Score [KPS], hemoglobin level, primary location of the vaginal lesion, macroscopic type, length of the involved vaginal wall, FIGO stage), microscopic (microscopic type, grade, mitotic index, presence of atypical mitoses, lymphatic vessels invasion, lymphocytes/plasmocytes infiltration, focal necrosis, VAIN-3), immunohistochemical (protein p53 expression, MIB-1 index), cytofluorometric (ploidity, index DI, S-phase fraction, proliferation index SG2M) factors. Results: Significantly better 5-year NED was observed in patients: < 60 years, KPS {<=} 80, FIGO stage I and II, grade G1-2, MIB-1 index < 70, S-phase fraction < 10, and proliferation index < 25. Independent factors for better prognosis in the multivariate Cox analysis were age < 60 years, FIGO stage I or II, and MIB-1 index < 70. Conclusion: Independent prognostic factors in the radically irradiated PIVC patients were as follows: age, FIGO stage, MIB-1 index. (orig.)

  13. SU-F-T-223: Radiotherapy Incident Reporting and Analysis System (RIRAS):Early Experience

    International Nuclear Information System (INIS)

    Kapoor, R; Palta, J; Hagan, M; Burkett, D; Leidholdt, E

    2016-01-01

    Background & Purpose: RIRAS is a web-based information system deployed on the Veterans Health Administration intranet in early 2014 to collect adverse events and good catch data; analyze the causes and contributing factors; and find ways to prevent future occurrences. Material and Methods: Incident learning consists of a feedback loop which starts with reporting an event, followed by analysis of contributing factors, and culminates in the development of a patient safety work product (PSWP) to prevent recurrence. RIRAS permits both anonymous and non-anonymous reporting. Each report is analyzed by a team of medical physicists who are independent of the reporting facility. The analysts usually contact the reporting facilities for additional information. We analyzed all reports and held telephonic interviews (when necessary) with the reporters. We then generated PSWPs with corrective/preventive and learning actions. Anonymous reporting is handled in the same manner, except without the ability to further interview the reporter. Results: In a significant number of reports, the causes and recommended preventive actions were considerably altered by the independent analysis and additional information from the facility. 130 reports have been entered in RIRAS; 9 misadministrations, 83 good catches, 3 anonymous good catches, and 35 earlier reported incidents from FY2005-14. 45% of the reported incidents occurred in the treatment delivery stages, 19% in on-treatment management, and 16% in pre-treatment verification. 80% of the good catches were found in the treatment delivery workflow. Majority of these incidents were due to inconsistent patient setup instructions or documentation, nonadherence to policies and procedures, lax time-out policy, distracted RTTs, and inadequate RTT staffing. Conclusion: RIRAS has identified many areas for improvement and elevated the quality and safety of radiation treatments in the VHA. We found that the ability to learn is significantly

  14. SU-F-T-223: Radiotherapy Incident Reporting and Analysis System (RIRAS):Early Experience

    Energy Technology Data Exchange (ETDEWEB)

    Kapoor, R; Palta, J; Hagan, M [National Radiation Oncology Program (10P4H), Dept. of Veterans Affairs, Richmond, VA (United States); Burkett, D; Leidholdt, E [National Health Physics Program (10P4X), Dept. of Veterans Affairs, Little Rock, AR (United States)

    2016-06-15

    Background & Purpose: RIRAS is a web-based information system deployed on the Veterans Health Administration intranet in early 2014 to collect adverse events and good catch data; analyze the causes and contributing factors; and find ways to prevent future occurrences. Material and Methods: Incident learning consists of a feedback loop which starts with reporting an event, followed by analysis of contributing factors, and culminates in the development of a patient safety work product (PSWP) to prevent recurrence. RIRAS permits both anonymous and non-anonymous reporting. Each report is analyzed by a team of medical physicists who are independent of the reporting facility. The analysts usually contact the reporting facilities for additional information. We analyzed all reports and held telephonic interviews (when necessary) with the reporters. We then generated PSWPs with corrective/preventive and learning actions. Anonymous reporting is handled in the same manner, except without the ability to further interview the reporter. Results: In a significant number of reports, the causes and recommended preventive actions were considerably altered by the independent analysis and additional information from the facility. 130 reports have been entered in RIRAS; 9 misadministrations, 83 good catches, 3 anonymous good catches, and 35 earlier reported incidents from FY2005-14. 45% of the reported incidents occurred in the treatment delivery stages, 19% in on-treatment management, and 16% in pre-treatment verification. 80% of the good catches were found in the treatment delivery workflow. Majority of these incidents were due to inconsistent patient setup instructions or documentation, nonadherence to policies and procedures, lax time-out policy, distracted RTTs, and inadequate RTT staffing. Conclusion: RIRAS has identified many areas for improvement and elevated the quality and safety of radiation treatments in the VHA. We found that the ability to learn is significantly

  15. Analysis of Dose Response for Circulatory Disease After Radiotherapy for Benign Disease

    Energy Technology Data Exchange (ETDEWEB)

    Little, Mark P., E-mail: mark.little@nih.gov [Radiation Epidemiology Branch, National Cancer Institute, Executive Plaza South, Rockville, Maryland (United States); Kleinerman, Ruth A. [Radiation Epidemiology Branch, National Cancer Institute, Executive Plaza South, Rockville, Maryland (United States); Stovall, Marilyn; Smith, Susan A. [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Mabuchi, Kiyohiko [Radiation Epidemiology Branch, National Cancer Institute, Executive Plaza South, Rockville, Maryland (United States)

    2012-12-01

    Purpose: To assess the shape of the dose-response for various circulatory disease endpoints, and modifiers by age and time since exposure. Methods and Materials: This was an analysis of the US peptic ulcer data testing for heterogeneity of radiogenic risk by circulatory disease endpoint (ischemic heart, cerebrovascular, other circulatory disease). Results: There were significant excess risks for all circulatory disease, with an excess relative risk Gy{sup -1} of 0.082 (95% CI 0.031-0.140), and ischemic heart disease, with an excess relative risk Gy{sup -1} of 0.102 (95% CI 0.039-0.174) (both p = 0.01), and indications of excess risk for stroke. There were no statistically significant (p > 0.2) differences between risks by endpoint, and few indications of curvature in the dose-response. There were significant (p < 0.001) modifications of relative risk by time since exposure, the magnitude of which did not vary between endpoints (p > 0.2). Risk modifications were similar if analysis was restricted to patients receiving radiation, although the relative risks were slightly larger and the risk of stroke failed to be significant. The slopes of the dose-response were generally consistent with those observed in the Japanese atomic bomb survivors and in occupationally and medically exposed groups. Conclusions: There were excess risks for a variety of circulatory diseases in this dataset, with significant modification of risk by time since exposure. The consistency of the dose-response slopes with those observed in radiotherapeutically treated groups at much higher dose, as well as in lower dose-exposed cohorts such as the Japanese atomic bomb survivors and nuclear workers, implies that there may be little sparing effect of fractionation of dose or low-dose-rate exposure.

  16. Multivariate analysis of factors predicting prostate dose in intensity-modulated radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Tomita, Tsuneyuki [Division of Radiology, Osaka Red Cross Hospital, Osaka (Japan); Nakamura, Mitsuhiro, E-mail: m_nkmr@kuhp.kyoto-u.ac.jp [Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto (Japan); Hirose, Yoshinori; Kitsuda, Kenji; Notogawa, Takuya; Miki, Katsuhito [Division of Radiology, Osaka Red Cross Hospital, Osaka (Japan); Nakamura, Kiyonao; Ishigaki, Takashi [Department of Radiation Oncology, Osaka Red Cross Hospital, Osaka (Japan)

    2014-01-01

    We conducted a multivariate analysis to determine relationships between prostate radiation dose and the state of surrounding organs, including organ volumes and the internal angle of the levator ani muscle (LAM), based on cone-beam computed tomography (CBCT) images after bone matching. We analyzed 270 CBCT data sets from 30 consecutive patients receiving intensity-modulated radiation therapy for prostate cancer. With patients in the supine position on a couch with the HipFix system, data for center of mass (COM) displacement of the prostate and the state of individual organs were acquired and compared between planning CT and CBCT scans. Dose distributions were then recalculated based on CBCT images. The relative effects of factors on the variance in COM, dose covering 95% of the prostate volume (D{sub 95%}), and percentage of prostate volume covered by the 100% isodose line (V{sub 100%}) were evaluated by a backward stepwise multiple regression analysis. COM displacement in the anterior-posterior direction (COM{sub AP}) correlated significantly with the rectum volume (δVr) and the internal LAM angle (δθ; R = 0.63). Weak correlations were seen for COM in the left-right (R = 0.18) and superior-inferior directions (R = 0.31). Strong correlations between COM{sub AP} and prostate D{sub 95%} and V{sub 100%} were observed (R ≥ 0.69). Additionally, the change ratios in δVr and δθ remained as predictors of prostate D{sub 95%} and V{sub 100%}. This study shows statistically that maintaining the same rectum volume and LAM state for both the planning CT simulation and treatment is important to ensure the correct prostate dose in the supine position with bone matching.

  17. Severe Late Toxicities Following Concomitant Chemoradiotherapy Compared to Radiotherapy Alone in Cervical Cancer: An Inter-era Analysis

    International Nuclear Information System (INIS)

    Gondi, Vinai; Bentzen, Søren M.; Sklenar, Kathryn L.; Dunn, Emily F.; Petereit, Daniel G.; Tannehill, Scott P.; Straub, Margaret; Bradley, Kristin A.

    2012-01-01

    Purpose: To compare rates of severe late toxicities following concomitant chemoradiotherapy and radiotherapy alone for cervical cancer. Methods and Materials: Patients with cervical cancer were treated at a single institution with radiotherapy alone or concomitant chemoradiotherapy for curative intent. Severe late toxicity was defined as grade ≥3 vaginal, urologic, or gastrointestinal toxicity or any pelvic fracture, using Common Terminology Criteria for Adverse Events version 4.0 (CTCAE), occurring ≥6 months from treatment completion and predating any salvage therapy. Severe late toxicity rates were compared after adjusting for pertinent covariates. Results: At 3 years, probability of vaginal severe late toxicity was 20.2% for radiotherapy alone and 35.1% for concomitant chemoradiotherapy (P=.026). At 3 years, probability of skeletal severe late toxicity was 1.6% for radiotherapy alone and 7.5% for concomitant chemoradiotherapy (P=.010). After adjustment for case mix, concomitant chemoradiotherapy was associated with higher vaginal (hazard ratio [HR] 3.0, 95% confidence interval [CI], 1.7-5.2, P 50 was associated with higher vaginal (HR 1.8, 95% CI 1.1-3.0, P=.013) and skeletal (HR 5.7, 95% CI 1.2-27.0, P=.028) severe late toxicity. Concomitant chemoradiotherapy was not associated with higher gastrointestinal (P=.886) or urologic (unadjusted, P=.053; adjusted, P=.063) severe late toxicity. Conclusion: Compared to radiotherapy alone, concomitant chemoradiotherapy is associated with higher rates of severe vaginal and skeletal late toxicities. Other predictive factors include dilator compliance for severe vaginal late toxicity and age for severe vaginal and skeletal late toxicities.

  18. Comparison of mortality outcomes after radical prostatectomy versus radiotherapy in patients with localized prostate cancer. A population-based analysis

    International Nuclear Information System (INIS)

    Abdollah, F.; Schmitges, J.; Sun, M.

    2012-01-01

    The objectives of this study were to compare the mortality outcomes of radical prostatectomy and radiotherapy as treatment modalities for patients with localized prostate cancer. Our cohort consisted of 68 665 patients with localized prostate cancer, treated with radical prostatectomy or radiotherapy, between 1992 and 2005. Propensity-score matching was used to minimize potential bias related to treatment assignment. Competing-risks analyses tested the effect of treatment type on cancer-specific mortality, after accounting for other-cause mortality. All analyses were stratified according to prostate cancer risk groups, baseline Charlson Comorbidity Index and age. For patients treated with radical prostatectomy versus radiotherapy, the 10-year cancer-specific mortality rates were 1.4 versus 3.9% in low-intermediate risk prostate cancer and 6.8 versus 11.5% in high-risk prostate cancer, respectively. Rates were 2.4 versus 5.9% in patients with Charlson Comorbidity Index of 0, 2.4 versus 5.1% in patients with Charlson Comorbidity Index of 1, and 2.9 versus 5.2% in patients with Charlson Comorbidity Index of ≥2. Rates were 2.1 versus 5.0% in patients aged 65-69 years, 2.8 versus 5.5% in patients aged 70-74 years, and 2.9 versus 7.6% in patients aged 75-80 years (all P<0.001). At multivariable analyses, radiotherapy was associated with less favorable cancer-specific mortality in all categories (all P<0.001). Patients treated with radical prostatectomy fare substantially better than those treated with radiotherapy. Patients with high-risk prostate cancer benefit the most from radical prostatectomy. Conversely, the lowest benefit was observed in patients with low-intermediate risk prostate cancer and/or multiple comorbidities. An intermediate benefit was observed in the other examined categories. (author)

  19. Postoperative Radiotherapy for Prostate Cancer: A Comparison of Four Consensus Guidelines and Dosimetric Evaluation of 3D-CRT Versus Tomotherapy IMRT

    International Nuclear Information System (INIS)

    Malone, Shawn; Croke, Jennifer; Roustan-Delatour, Nicolas; Belanger, Eric; Avruch, Leonard; Malone, Colin; Morash, Christopher; Kayser, Cathleen; Underhill, Kathryn; Li Yan; Malone, Kyle; Nyiri, Balazs; Spaans, Johanna

    2012-01-01

    Purpose: Despite the benefits of adjuvant radiotherapy after radical prostatectomy, approximately one-half of patients relapse. Four consensus guidelines have been published (European Organization for Research and Treatment of Cancer, Faculty of Radiation Oncology Genito-Urinary Group, Princess Margaret Hospital, Radiation Therapy Oncology Group) with the aim of standardizing the clinical target volume (CTV) delineation and improve outcomes. To date, no attempt has been made to compare these guidelines in terms of treatment volumes or organ at risk (OAR) irradiation. The extent to which the guideline-derived plans meet the dosimetric constraints of present trials or of the Quantitative Analysis of Normal Tissue Effects in the Clinic (QUANTEC) trial is also unknown. Our study also explored the dosimetric benefits of intensity-modulated radiotherapy (IMRT). Methods and Materials: A total of 20 patients treated with postoperative RT were included. The three-dimensional conformal radiotherapy (3D-CRT) plans were applied to cover the guideline-generated planning target volumes (66 Gy in 33 fractions). Dose–volume histograms (DVHs) were analyzed for CTV/planning target volume coverage and to evaluate OAR irradiation. The OAR DVHs were compared with the constraints proposed in the QUANTEC and Radiotherapy and Androgen Deprivation In Combination After Local Surgery (RADICALS) trials. 3D-CRT plans were compared with the tomotherapy plans for the Radiation Therapy Oncology Group planning target volume to evaluate the advantages of IMRT. Results: The CTV differed significantly between guidelines (p < 0.001). The European Organization for Research and Treatment of Cancer-CTVs were significantly smaller than the other CTVs (p < 0.001). Differences in prostate bed coverage superiorly accounted for the major volumetric differences between the guidelines. Using 3D-CRT, the DVHs rarely met the QUANTEC or RADICALS rectal constraints, independent of the guideline used. The RADICALS

  20. Radiotherapy May Offer a Recurrence and Survival Benefit in Rectal Cancers Treated Surgically with Transanal Endoscopic Microsurgery: A Systematic Review and Meta-analysis.

    Science.gov (United States)

    Sideris, Michail; Donaldson, Ana Nora; Hanrahan, John; Grunwald, Matthew; Papagrigoriadis, Savvas

    2018-04-01

    Several studies report outcomes of Transanal Endoscopic Microsurgery (TEMS) surgery in combination with radiotherapy, however the combination of those treatments is provided mostly on an adhoc individual basis and the role of radiotherapy remains unclear. The aim of this study was to identify the effect of neo-adjuvant or adjuvant radiotherapy in the oncological outcomes of rectal cancer treated surgically with TEMS. We performed a systematic review of the literature on MEDLINE and Pubmed databases. Data were extracted by two independent reviewers and meta-analyzed using an inverse variance heterogeneity model to calculate overall (pooled) effect sizes for survival or recurrence of disease against neo+/-adjuvant treatment. A total of 48 studies were included in the qualitative meta-analysis which included 3,285 patients with rectal cancer. The overall survival odds ratio (OR), was 9.39 (95% CI=6.1-14.4) with a Cochran's Q variable of 151.7 on 47 degrees of freedom (d.f.) (p=0.000). Recurrence-free OR was 8.7 (95%CI=6.58-11.44) with a Cochran's Q variable of Q=145.2 on 44 d.f. (p=0.000). Studies which contained more than 10% of pT3 tumours, and provided neo+/-adjuvant treatment in more than 35% of cases, were associated with survival benefit, as demonstrated by an overall odds of survival of 32.2 (95%CI=16.3-63.5, p=0.001, Q=8.4, p=0.21). Studies that contained more than 10% of pT3 tumours and provided neo+/-adjuvant treatment in more than 20% of the cases had an overall effect size of recurrence-free odds of 20.23 (95%CI=13.84-29.57, p=0.000, Q=2.18, p=0.54). There seems to be a benefit from radiotherapy on overall survival and recurrence-free odds, which is more apparent in cohorts with more than 10% of pT3 tumours. Our results suggest that neo-adjuvant or adjuvant radiotherapy should be considered for inclusion in formal treatment protocols for rectal cancers treated with TEMS as they offer a recurrence and survival benefit. Copyright© 2018, International

  1. Comparing conformal, arc radiotherapy and helical tomotherapy in craniospinal irradiation planning.

    Science.gov (United States)

    Myers, Pamela A; Mavroidis, Panayiotis; Papanikolaou, Nikos; Stathakis, Sotirios

    2014-09-08

    Currently, radiotherapy treatment plan acceptance is based primarily on dosimetric performance measures. However, use of radiobiological analysis to assess benefit in terms of tumor control and harm in terms of injury to normal tissues can be advantageous. For pediatric craniospinal axis irradiation (CSI) patients, in particular, knowing the technique that will optimize the probabilities of benefit versus injury can lead to better long-term outcomes. Twenty-four CSI pediatric patients (median age 10) were retrospectively planned with three techniques: three-dimensional conformal radiation therapy (3D CRT), volumetric-modulated arc therapy (VMAT), and helical tomotherapy (HT). VMAT plans consisted of one superior and one inferior full arc, and tomotherapy plans were created using a 5.02cm field width and helical pitch of 0.287. Each plan was normalized to 95% of target volume (whole brain and spinal cord) receiving prescription dose 23.4Gy in 13 fractions. Using an in-house MATLAB code and DVH data from each plan, the three techniques were evaluated based on biologically effective uniform dose (D=), the complication-free tumor control probability (P+), and the width of the therapeutically beneficial range. Overall, 3D CRT and VMAT plans had similar values of D= (24.1 and 24.2 Gy), while HT had a D= slightly lower (23.6 Gy). The average values of the P+ index were 64.6, 67.4, and 56.6% for 3D CRT, VMAT, and HT plans, respectively, with the VMAT plans having a statistically significant increase in P+. Optimal values of D= were 28.4, 33.0, and 31.9 Gy for 3D CRT, VMAT, and HT plans, respectively. Although P+ values that correspond to the initial dose prescription were lower for HT, after optimizing the D= prescription level, the optimal P+ became 94.1, 99.5, and 99.6% for 3D CRT, VMAT, and HT, respectively, with the VMAT and HT plans having statistically significant increases in P+. If the optimal dose level is prescribed using a radiobiological evaluation method, as

  2. Dosimetric and motion analysis of margin-intensive therapy by stereotactic ablative radiotherapy for resectable pancreatic cancer

    Directory of Open Access Journals (Sweden)

    Heinzerling John H

    2011-10-01

    Full Text Available Abstract Background The retroperitoneal margin is a common site of positive surgical margins in patients with resectable pancreatic cancer. Preoperative margin-intensive therapy (MIT involves delivery of a single high dose of ablative radiotherapy (30 Gy focused on this surgically inaccessible margin, utilizing stereotactic techniques in an effort to reduce local failure following surgery. In this study, we investigated the motion of regional organs at risk (OAR utilizing 4DCT, evaluated the dosimetric effects of abdominal compression (AC to reduce regional motion, and compared various planning techniques to optimize MIT. Methods 10 patients were evaluated with 4DCT scans. All 10 patients had scans using AC and seven of the 10 patients had scans both with and without AC. The peak respiratory abdominal organ and major vessel centroid excursion was measured. A "sub-GTV" region was defined by a radiation oncologist and surgical oncologist encompassing the retroperitoneal margin typically lateral and posterior to the superior mesenteric artery (SMA, and a 3-5 mm margin was added to constitute the PTV. Identical 3D non-coplanar SABR (3DSABR plans were designed for the average compression and non-compression scans. Compression scans were planned with 3DSABR, coplanar IMRT (IMRT, and Cyberknife (CK planning techniques. Dose volume analysis was undertaken for various endpoints, comparing OAR doses with and without AC and for different planning methods. Results The mean PTV size was 20.2 cm3. Regional vessel motion of the SMA, celiac trunk, and renal vessels was small ( 5 mm, so AC has been used in all patients enrolled thus far. AC did not significantly increase OAR dose including the stomach and traverse colon. There were several statistically significant differences in the doses to OARs as a function of the type of planning modality used. Conclusions AC does not significantly reduce the limited motion of structures in close proximity to the MIT target

  3. [Analysis of the therapeutic effects of different treatment modalities on the outcomes of 87 patients with lung oligometastasis from nasopharyngeal carcinoma after radiotherapy].

    Science.gov (United States)

    Tang, Q; Hu, Q Y; Piao, Y F; Hua, Y H; Chen, X Z

    2016-03-23

    The aim of the present study was to evaluate the efficacy of three different modalities in treatment of lung oligometastases from nasopharyngeal carcinoma (NPC) after radiotherapy and to identify a more appropriate treatment modality. The clinical data of 87 cases of lung oligometastases from NPC were analyzed retrospectively. Among them, 33 patients underwent local small-field irradiation+ /- chemotherapy, 28 underwent whole-lung irradiation+ chemotherapy, and 26 underwent simple chemotherapy. The survival rates were calculated using Kaplan-Meier analysis. The differences among the modalities were evaluated using the log-rank test. Cox univariate and multivariate analyses were performed to determine the influencing factors. The 3-year lung metastasis survival (LMS) rates of patients with lung metastasis undergoing the three treatment modalities (local small-field irradiation+ /-chemotherapy, whole-lung irradiation+ chemotherapy and chemotherapy alone) were 89.3%, 72.7%, and 72.4%, respectively, showing a significant difference between the groups (P=0.003). Further subgroup analysis showed that the 5-year LMS rate was significantly higher in the local small-field irradiation+ /-chemotherapy group than that in the whole-lung irradiation+ chemotherapy group and chemotherapy alone group (P=0.001). The 2-year progression-free survival (PFS) rates of the three groups were 57.1%, 25.8% and 3.8%, respectively, showing significant intergroup differences (P=0.002 and P<0.001). Multivariate analysis indicated that compared with the whole lung irradiation group and the chemotherapy alone group, the local irradiation+ /- chemotherapy is an independent favorable prognostic factor for LMS and PFS (P<0.05). Local radiotherapy combined with systemic chemotherapy is the best therapeutic modality for lung oligometastases derived from NPC after radiotherapy, improving the LMS and prolonging the PFS.

  4. Radiotherapy of benign diseases

    International Nuclear Information System (INIS)

    Haase, W.

    1982-01-01

    Still today radiotherapy is of decisive relevance for several benign diseases. The following ones are briefly described in this introductory article: 1. Certain inflammatory and degenerative diseases as furuncles in the face, acute thrombophlebitis, recurrent sudoriparous abscesses, degenerative skeletal diseases, cervical syndrome and others; 2. rheumatic joint diseases; 3. Bechterew's disease; 4. primary presenile osteoporosis; 5. synringomyelia; 6. endocrine ophthalmopathy; 7. hypertrophic processes of the connective tissue; 8. hemangiomas. A detailed discussion and a profit-risk analysis is provided in the individual chapters of the magazine. (MG) [de

  5. "SABER": A new software tool for radiotherapy treatment plan evaluation.

    Science.gov (United States)

    Zhao, Bo; Joiner, Michael C; Orton, Colin G; Burmeister, Jay

    2010-11-01

    Both spatial and biological information are necessary in order to perform true optimization of a treatment plan and for predicting clinical outcome. The goal of this work is to develop an enhanced treatment plan evaluation tool which incorporates biological parameters and retains spatial dose information. A software system is developed which provides biological plan evaluation with a novel combination of features. It incorporates hyper-radiosensitivity using the induced-repair model and applies the new concept of dose convolution filter (DCF) to simulate dose wash-out effects due to cell migration, bystander effect, and/or tissue motion during treatment. Further, the concept of spatial DVH (sDVH) is introduced to evaluate and potentially optimize the spatial dose distribution in the target volume. Finally, generalized equivalent uniform dose is derived from both the physical dose distribution (gEUD) and the distribution of equivalent dose in 2 Gy fractions (gEUD2) and the software provides three separate models for calculation of tumor control probability (TCP), normal tissue complication probability (NTCP), and probability of uncomplicated tumor control (P+). TCP, NTCP, and P+ are provided as a function of prescribed dose and multivariable TCP, NTCP, and P+ plots are provided to illustrate the dependence on individual parameters used to calculate these quantities. Ten plans from two clinical treatment sites are selected to test the three calculation models provided by this software. By retaining both spatial and biological information about the dose distribution, the software is able to distinguish features of radiotherapy treatment plans not discernible using commercial systems. Plans that have similar DVHs may have different spatial and biological characteristics and the application of novel tools such as sDVH and DCF within the software may substantially change the apparent plan quality or predicted plan metrics such as TCP and NTCP. For the cases examined

  6. External beam radiotherapy for painful osseous metastases: pooled data dose response analysis

    International Nuclear Information System (INIS)

    Ben-Josef, Edgar; Shamsa, Falah; Youssef, Emad; Porter, Arthur T.

    1999-01-01

    Purpose: Although the effectiveness of external beam irradiation in palliation of pain from osseous metastases is well established, the optimal fractionation schedule has not been determined. Clinical studies to date have failed to demonstrate an advantage for higher doses. To further address this issue, we conducted a pooled dose response analysis using data from published Phase III clinical trials. Methods and Materials: Complete response (CR) was used as an endpoint because it was felt to be least susceptible to inconsistencies in assessment.The biological effective dose (BED) was calculated for each schedule using the linear-quadratic model and an α/β of 10. Using SAS version 6.12, the data were fitted using a weighted linear regression, a logistic model, and the spline technique. Finally, BED was categorized, and odds ratios for each level were calculated. Results: CR was assessed early and late in 383 and 1,007 patients, respectively. Linear regression on the early-response data yielded a poor fit and a nonsignificant dose coefficient. With the late-response data, there was an excellent fit (R-square = 0.842) and a highly significant dose coefficient (p = 0.0002). Fitting early CR to a logistic model, we could not establish a significant dose response relationship. However, with the late-response data there was an excellent fit and the dose coefficient was significantly different from zero (0.017 ± 0.00524; p = 0.0012). Application of the spline technique or removal of an outlier resulted in an improved fit (p 0.048 and p = 0.0001, respectively). Using BED of < 14.4 Gy as a reference level, the odds ratios for late CR were 2.29-3.32 (BED of 19.5-51.4 Gy, respectively). Conclusion: Our results demonstrate a clear dose-response for pain relief. Further testing of high intensity regiments is warranted

  7. A Multiplan Treatment-Planning Framework: A Paradigm Shift for Intensity-Modulated Radiotherapy

    International Nuclear Information System (INIS)

    Meyer, Robert R.; Zhang, Hao H.; Goadrich, Laura; Nazareth, Daryl P.; Shi Leyuan; D'Souza, Warren D.

    2007-01-01

    Purpose: To describe a multiplan intensity-modulated radiotherapy (IMRT) planning framework, and to describe a decision support system (DSS) for ranking multiple plans and modeling the planning surface. Methods and Materials: One hundred twenty-five plans were generated sequentially for a head-and-neck case and a pelvic case by varying the dose-volume constraints on each of the organs at risk (OARs). A DSS was used to rank plans according to dose-volume histogram (DVH) values, as well as equivalent uniform dose (EUD) values. Two methods for ranking treatment plans were evaluated: composite criteria and pre-emptive selection. The planning surface determined by the results was modeled using quadratic functions. Results: The DSS provided an easy-to-use interface for the comparison of multiple plan features. Plan ranking resulted in the identification of one to three 'optimal' plans. The planning surface models had good predictive capability with respect to both DVH values and EUD values and generally, errors of <6%. Models generated by minimizing the maximum relative error had significantly lower relative errors than models obtained by minimizing the sum of squared errors. Using the quadratic model, plan properties for one OAR were determined as a function of the other OAR constraint settings. The modeled plan surface can then be used to understand the interdependence of competing planning objectives. Conclusion: The DSS can be used to aid the planner in the selection of the most desirable plan. The collection of quadratic models constructed from the plan data to predict DVH and EUD values generally showed excellent agreement with the actual plan values

  8. Evaluation of dosimetric variance in whole breast forward-planned intensity-modulated radiotherapy based on 4DCT and 3DCT

    International Nuclear Information System (INIS)

    Wang Wei; Li Jianbin; Hu Hongguang; Sun Tao; Xu Min; Fan Tingyong; Shao Qian

    2013-01-01

    This study was performed to explore and compare the dosimetric variance caused by respiratory movement in the breast during forward-planned intensity-modulated radiotherapy (IMRT) after breast-conserving surgery. A total of 17 enrolled patients underwent the three-dimensional computed tomography (3DCT) simulation scans followed by four-dimensional computed tomography (4DCT) simulation scans during free breathing. The treatment planning constructed using the 3DCT images was copied and applied to the end expiration (EE) and end inspiration (EI) scans and the dose distributions were calculated separately. CTV volume variance amplitude was very small (11.93±28.64 cm 3 ), and the percentage change of CTV volumes receiving 50 Gy and 55 Gy between different scans were all less than 0.8%. There was no statistically significant difference between EI and EE scans (Z=-0.26, P=0.795). However, significant differences were found when comparing the D mean at 3DCT planning with the EI and EE planning (P=0.010 and 0.019, respectively). The homogeneity index at EI, EE and 3D plannings were 0.139, 0.141 and 0.127, respectively, and significant differences existed between 3D and EI, and between 3D and EE (P=0.001 and 0.006, respectively). The conformal index (CI) increased significantly in 3D treatment planning (0.74±0.07) compared with the EI and EE phase plannings (P=0.005 and 0.005, respectively). The V 30 , V 40 , V 50 and D mean of the ipsilateral lung for EE phase planning were significantly lower than for EI (P=0.001-0.042). There were no significant differences in all the dose-volume histogram (DVH) parameters for the heart among these plannings (P=0.128-0.866). The breast deformation during respiration can be disregarded in whole breast IMRT. 3D treatment planning is sufficient for whole breast forward-planned IMRT on the basis of our DVH analysis, but 4D treatment planning, breath-hold, or respiratory gate may ensure precise delivery of radiation dose. (author)

  9. National arrangements for radiotherapy

    International Nuclear Information System (INIS)

    2007-01-01

    After a presentation of several letters exchanged between the French health ministry and public agencies in charge of public health or nuclear safety after a radiotherapy accident in Epinal, this report comments the evolution of needs in cancerology care and the place given to radiotherapy. It outlines the technological and organisational evolution of radiotherapy and presents the distribution of radiotherapy equipment, of radio-therapists and other radiotherapy professionals in France. Within the context of radiotherapy accidents which occurred in 2007, it presents the regulatory arrangements which aimed at improving the safety, short term and middle term arrangements which are needed to support and structure radiotherapy practice quality. It stresses the fact that the system will deeply evolve by implementing a radiotherapy vigilance arrangement and a permanent follow-on and adaptation plan based on surveys and the creation of a national committee

  10. Radiotherapy of malignant lymphomas

    Energy Technology Data Exchange (ETDEWEB)

    Kujawska, J [Instytut Onkologii, Krakow (Poland)

    1979-01-01

    The paper discusses current views on the role of radiotherapy in the treatment of patients with malignant lymphomas. Principles of radiotherapy employed in the Institute of Oncology in Cracow in case of patients with malignant lymphomas are also presented.

  11. A dosimetric comparison of fan-beam intensity modulated radiotherapy with gamma knife stereotactic radiosurgery for treating intermediate intracranial lesions

    International Nuclear Information System (INIS)

    Ma Lijun; Xia Ping; Verhey, Lynn J.; Boyer, Arthur L.

    1999-01-01

    Purpose: To compare and evaluate treatment plans for the fan-beam intensity modulated radiotherapy and the Gamma Knife radiosurgery for treating medium-size intracranial lesions (range 4-25 cm 3 ). Methods and Materials: Treatment plans were developed for the Leksell Gamma Knife and a fan-beam inverse treatment planning system for intensity modulated radiotherapy. Treatment plan comparisons were carried out using dose-volume histogram (DVH), tissue-volume ratio (TVR), and maximum dose to the prescription dose (MDPD) ratio. The study was carried out for both simulated targets and clinical targets with irregular shapes and at different locations. Results: The MDPD ratio was significantly greater for the Gamma Knife plans than for the fan-beam IMRT plans. The Gamma Knife plans produced equivalent TVR values to the fan-beam IMRT plans. Based on the DVH comparison, the fan-beam IMRT delivered significantly more dose to the normal brain tissue than the Gamma Knife. The results of the comparison were found to be insensitive to the target locations. Conclusion: The Gamma Knife is better than the fan-beam IMRT in sparing normal brain tissue while producing equivalent tumor dose conformity for treating medium-size intracranial lesions. However, the target dose homogeneity is significantly better for the fan-beam IMRT than for the Gamma Knife

  12. Impact of the radiotherapy technique on the correlation between dose–volume histograms of the bladder wall defined on MRI imaging and dose–volume/surface histograms in prostate cancer patients

    International Nuclear Information System (INIS)

    Maggio, Angelo; Carillo, Viviana; Perna, Lucia; Fiorino, Claudio; Cozzarini, Cesare; Rancati, Tiziana; Valdagni, Riccardo; Gabriele, Pietro

    2013-01-01

    The aim of this study was to evaluate the correlation between the ‘true’ absolute and relative dose–volume histograms (DVHs) of the bladder wall, dose–wall histogram (DWH) defined on MRI imaging and other surrogates of bladder dosimetry in prostate cancer patients, planned both with 3D-conformal and intensity-modulated radiation therapy (IMRT) techniques. For 17 prostate cancer patients, previously treated with radical intent, CT and MRI scans were acquired and matched. The contours of bladder walls were drawn by using MRI images. External bladder surfaces were then used to generate artificial bladder walls by performing automatic contractions of 5, 7 and 10 mm. For each patient a 3D conformal radiotherapy (3DCRT) and an IMRT treatment plan was generated with a prescription dose of 77.4 Gy (1.8 Gy/fr) and DVH of the whole bladder of the artificial walls (DVH-5/10) and dose–surface histograms (DSHs) were calculated and compared against the DWH in absolute and relative value, for both treatment planning techniques. A specific software (VODCA v. 4.4.0, MSS Inc.) was used for calculating the dose–volume/surface histogram. Correlation was quantified for selected dose–volume/surface parameters by the Spearman correlation coefficient. The agreement between %DWH and DVH5, DVH7 and DVH10 was found to be very good (maximum average deviations below 2%, SD < 5%): DVH5 showed the best agreement. The correlation was slightly better for absolute (R = 0.80–0.94) compared to relative (R = 0.66–0.92) histograms. The DSH was also found to be highly correlated with the DWH, although slightly higher deviations were generally found. The DVH was not a good surrogate of the DWH (R < 0.7 for most of parameters). When comparing the two treatment techniques, more pronounced differences between relative histograms were seen for IMRT with respect to 3DCRT (p < 0.0001). (note)

  13. Therapeutic effect and prognostic analysis of intensity-modulated radiotherapy for primary hepatocellular carcinoma with portal vein and/or inferior vena cava tumor thrombus

    Directory of Open Access Journals (Sweden)

    HUANG Long

    2015-06-01

    Full Text Available ObjectiveTo determine the efficacy and prognostic factors of intensity-modulated radiotherapy (IMRT for primary hepatocellular carcinoma (HCC with portal vein and/or inferior vena cava tumor thrombus. MethodsTwenty-three HCC patients with portal vein and/or inferior vena cava tumor thrombus received IMRT with an 8 MV linear accelerator at the Cancer Center of General Hospital of Armed Police Forces, Anhui Medical University, from April 2008 to August 2011. A single dose of 3 to 6 Gy was delivered at five fractions per week, with a total dose of 56 to 96 Gy and a median dose of 60 Gy. Survival time was recorded, and adverse reactions were evaluated. Survival rate calculation and survival analysis were performed using the Kaplan-Meier method. Comparison of categorical between two groups was made by chi-square test. ResultsOne patient did not complete radiotherapy due to upper gastrointestinal bleeding. Of 22 patients who completed IMRT, 4 achieved complete remission and 10 achieved partial remission, with an overall response rate of 63.7%. Our analysis showed that the type of tumor thrombus and tumor size were associated with tumor response rate and were significant prognostic factors (P<0.05. The median survival time was 13.4 months. The 1-, 2-, and 3-year survival rates were 59%, 27%, and 18%, respectively. The 22 patients who completed radiotherapy did not experience acute radiation injury or late adverse outcomes such as radiation-induced liver disease. ConclusionThis study suggests IMRT is a safe and effective treatment option for HCC patients with portal vein and/or inferior vena cava tumor thrombus.

  14. Safety and efficacy of stereotactic body radiotherapy as primary treatment for vertebral metastases: a multi-institutional analysis

    International Nuclear Information System (INIS)

    Guckenberger, Matthias; Mantel, Frederick; Gerszten, Peter C; Flickinger, John C; Sahgal, Arjun; Létourneau, Daniel; Grills, Inga S; Jawad, Maha; Fahim, Daniel K; Shin, John H; Winey, Brian; Sheehan, Jason; Kersh, Ron

    2014-01-01

    To evaluate patient selection criteria, methodology, safety and clinical outcomes of stereotactic body radiotherapy (SBRT) for treatment of vertebral metastases. Eight centers from the United States (n = 5), Canada (n = 2) and Germany (n = 1) participated in the retrospective study and analyzed 301 patients with 387 vertebral metastases. No patient had been exposed to prior radiation at the treatment site. All patients were treated with linac-based SBRT using cone-beam CT image-guidance and online correction of set-up errors in six degrees of freedom. 387 spinal metastases were treated and the median follow-up was 11.8 months. The median number of consecutive vertebrae treated in a single volume was one (range, 1-6), and the median total dose was 24 Gy (range 8-60 Gy) in 3 fractions (range 1-20). The median EQD2 10 was 38 Gy (range 12-81 Gy). Median overall survival (OS) was 19.5 months and local tumor control (LC) at two years was 83.9%. On multivariate analysis for OS, male sex (p < 0.001; HR = 0.44), performance status <90 (p < 0.001; HR = 0.46), presence of visceral metastases (p = 0.007; HR = 0.50), uncontrolled systemic disease (p = 0.007; HR = 0.45), >1 vertebra treated with SBRT (p = 0.04; HR = 0.62) were correlated with worse outcomes. For LC, an interval between primary diagnosis of cancer and SBRT of ≤30 months (p = 0.01; HR = 0.27) and histology of primary disease (NSCLC, renal cell cancer, melanoma, other) (p = 0.01; HR = 0.21) were correlated with worse LC. Vertebral compression fractures progressed and developed de novo in 4.1% and 3.6%, respectively. Other adverse events were rare and no radiation induced myelopathy reported. This multi-institutional cohort study reports high rates of efficacy with spine SBRT. At this time the optimal fractionation within high dose practice is unknown

  15. Predictors of severe late radiotherapy-related toxicity after hyperfractionated radiotherapy with or without concomitant cisplatin in locally advanced head and neck cancer. Secondary retrospective analysis of a randomized phase III trial (SAKK 10/94)

    International Nuclear Information System (INIS)

    Ghadjar, Pirus; Simcock, Mathew; Zimmermann, Frank; Betz, Michael; Bodis, Stephan; Bernier, Jacques; Studer, Gabriela; Aebersold, Daniel M.

    2012-01-01

    Background and purpose: This secondary analysis was performed to identify predictive factors for severe late radiotherapy (RT)-related toxicity after treatment with hyperfractionated RT +/− concomitant cisplatin in locally advanced head and neck cancer. Materials and methods: Patients were retrospectively analyzed from the previously reported randomized phase III trial: SAKK 10/94. Severe late RT-related toxicity was defined as late RTOG ⩾ grade 3 toxicity starting 3 months after end of RT and/or potential treatment-related death within 3 years of randomization. Results: Two hundred and thirteen randomized patients were analyzed; 84 (39%) experienced severe late RT-related toxicity. With median follow-up of 9.7 years (range, 0.4–15.4 years), median time to severe late RT-related toxicity was 9.6 years. In the univariate Cox proportional hazards model the following variables were associated with severe late RT-related toxicity: advanced N-classification (p < 0.001); technically unresectable disease (p = 0.04); weight loss ratio (p = 0.003); supportive measures (p = 0.009) and severe acute dysphagia (p = 0.001). In the subsequent multivariate analysis all variables except use of supportive measures remained statistically significant. Conclusions: Chemotherapy did not appear to affect severe late RT-related toxicity, but advanced N-classification, technically unresectable disease, weight loss ratio, and severe acute dysphagia were independent predictive factors for severe late RT-related toxicity.

  16. Patient safety in external beam radiotherapy, results of the ACCIRAD project: Current status of proactive risk assessment, reactive analysis of events, and reporting and learning systems in Europe.

    Science.gov (United States)

    Malicki, Julian; Bly, Ritva; Bulot, Mireille; Godet, Jean-Luc; Jahnen, Andreas; Krengli, Marco; Maingon, Philippe; Prieto Martin, Carlos; Przybylska, Kamila; Skrobała, Agnieszka; Valero, Marc; Jarvinen, Hannu

    2017-04-01

    To describe the current status of implementation of European directives for risk management in radiotherapy and to assess variability in risk management in the following areas: 1) in-country regulatory framework; 2) proactive risk assessment; (3) reactive analysis of events; and (4) reporting and learning systems. The original data were collected as part of the ACCIRAD project through two online surveys. Risk assessment criteria are closely associated with quality assurance programs. Only 9/32 responding countries (28%) with national regulations reported clear "requirements" for proactive risk assessment and/or reactive risk analysis, with wide variability in assessment methods. Reporting of adverse error events is mandatory in most (70%) but not all surveyed countries. Most European countries have taken steps to implement European directives designed to reduce the probability and magnitude of accidents in radiotherapy. Variability between countries is substantial in terms of legal frameworks, tools used to conduct proactive risk assessment and reactive analysis of events, and in the reporting and learning systems utilized. These findings underscore the need for greater harmonisation in common terminology, classification and reporting practices across Europe to improve patient safety and to enable more reliable inter-country comparisons. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Dosimetric characterization of VIPARnd gel by optical analysis to high-energy photon beam used in external radiotherapy

    International Nuclear Information System (INIS)

    Dias, Juliana R.; Lima, Renata S.; Lopes, Roseany de V. Vieira; Ceschin, Artemis Marti

    2015-01-01

    Polymer gel dosimetry has been proposed as a possibility for measurements of dose distribution in radiotherapy. This work aims to evaluate the dosimetric characteristics of a VIPARnd for 6 MV photon beam used in radiotherapy using optical investigations. The absorbance spectrum of irradiated gel dosimeter was optical evaluated with spectrophotometer techniques and with CMOS camera readout for dose range of 0 to 50 Gy. Data shows that the VIPARnd has a maximum absorbance at 300 to 320 nm depending on the absorbed dose. The CMOS camera readouts were obtained in RGB color, the absorbance measurements suggest a major response of dose for blue matrix verified with data. The dose-response curve for blue component showed interval of linearity from 1 Gy to 20 Gy. (author)

  18. Health-related quality of life after adjuvant and salvage postoperative radiotherapy for prostate cancer - A prospective analysis

    International Nuclear Information System (INIS)

    Pinkawa, Michael; Fischedick, Karin; Asadpour, Branka; Gagel, Bernd; Piroth, Marc D.; Holy, Richard; Krenkel, Barbara; Eble, Michael J.

    2008-01-01

    Background and purpose: The aim of the study was to analyze health-related quality of life changes after postoperative radiotherapy (RT) for prostate cancer. Materials and methods: A group of 101 patients has been surveyed prospectively before (time A), at the last day (B), two months after (C) and >1 year after (D) RT using a validated questionnaire (Expanded Prostate Cancer Index Composite) with urinary, bowel, sexual and hormonal domains. The prostatic fossa was treated with a four-field box technique up to a total dose of 66.6 Gy. Results: While median urinary scores reached baseline levels already two months after radiotherapy (function/bother scores at time A-B-C-D: 94/89-89/75-94/89-94/89; A vs. B: p 1 year, only minor HRQOL changes occurred in comparison to baseline scores

  19. Hyperthermia and radiotherapy

    International Nuclear Information System (INIS)

    Fitspatrick, C.

    1990-01-01

    Hyperthermia and radiotherapy have for long been used to assist in the control of tumours, either as separate entities, or, in a combined treatment scheme. This paper outlines why hyperthermia works, thermal dose and the considerations required in the timing when hyperthermia is combined with radiotherapy. Previously reported results for hyperthermia and radiotherapy used together are also presented. 8 refs., 8 tabs

  20. Fibrotic changes after postmastectomy radiotherapy and reconstructive surgery in breast cancer. A retrospective analysis in 109 patients

    International Nuclear Information System (INIS)

    Classen, Johannes; St. Vincentius-Kliniken, Karlsruhe; Nitzsche, Sibille; Wallwiener, Diethelm; Brucker, Sara; Kristen, Peter; Souchon, Rainer; Bamberg, Michael

    2010-01-01

    The purpose of this study was to analyze the probability and time course of fibrotic changes in breast reconstruction before or after postmastectomy radiotherapy (PMRT). Between 1995 and 2004, 109 patients were treated with PMRT at Tuebingen University and underwent heterologous (HL) or autologous (AL) breast reconstruction prior or subsequent to radiation therapy. Fibrosis of the reconstructed breast after radiotherapy was assessed using the Baker score for HL reconstructions and the Common Terminology Criteria for Adverse Events (CTCAE) for all patients. Actuarial rates of fibrosis were calculated for the maximum degree acquired during follow- up and at the last follow-up visit documented. Median time to follow-up was 34 months (3-227 months). Radiotherapy was applied with a median total dose of 50.4 Gy. A total of 44 patients (40.4%) received a boost treatment with a median dose of 10 Gy. Breast reconstruction was performed with AL, HL, or combined techniques in 20, 82, and 7 patients, respectively. The 3-year incidence of ≥ grade III maximum fibrosis was 20% and 43% for Baker and CTCAE scores, respectively. The corresponding figures for fibrosis at last follow-up visit were 18% and 2%. The 3-year rate of surgical correction of the contralateral breast was 30%. Initially unplanned surgery of the reconstructed breast was performed in 39 patients (35.8%). Boost treatment and type of cosmetic surgery (HL vs. AL) were not significantly associated with the incidence of fibrosis. We found severe fibrosis to be a frequent complication after PMRT radiotherapy and breast reconstruction. However, surgical intervention can ameliorate the majority of high grade fibrotic events leading to acceptable long-term results. No treatment parameters associated with the rate of fibrosis could be identified. (orig.)

  1. An analysis of the experiences of radiography and radiotherapy students who are carers at one UK university

    International Nuclear Information System (INIS)

    Hussain, Zainab; Pickering, Vicki; Percy, Dave; Crane, Julie; Bogg, Jan

    2011-01-01

    Purpose: This is a mixed methods study of the experiences and attendance of radiography and radiotherapy students who are carers at one UK university, Undergraduate radiography and radiotherapy programmes are attracting increasing numbers of mature students. It is therefore likely that the number of students with carer responsibilities is also increasing. This study explores the experiences of higher education of students with caring responsibilities. The aim of the study is to identify possible strategies and practices to enhance the student experience and so to work towards compliance with the recent Equality Act 2010. Method: All students on the radiography (n = 130) and radiotherapy (n = 97) programmes were invited to complete a short questionnaire. Students who identified themselves as carers on the questionnaire were invited to participate in focus group sessions. Due to the issues raised in the focus groups by students with regard to attendance at university and clinical placement, student absence rates were also investigated for students with and without caring responsibilities. Results: 215 students completed the questionnaire. 30 of the 215 students identified themselves as carers. 18 carers agreed to take part in focus groups. Carers reported that having fees paid by the NHS was an important choice factor for higher education. Carers' main concerns were: timetabling, finances, support after exam failures, understanding from academic staff and attendance issues. Examination of absence rates demonstrated carers had significantly (p = 0.000) less absence than non-carers for radiography and no significant differences for radiotherapy (p = 0.105). Conclusion: The NHS states it must be reflective of the community it serves. Thus those responsible for delivering health professional programmes have a duty to recruit and retain a diverse student population. The introduction of the Equality Act 2010 means higher education institutions must consider the needs of

  2. Multi-Institutional Analysis of Solitary Extramedullary Plasmacytoma of the Head and Neck Treated With Curative Radiotherapy

    International Nuclear Information System (INIS)

    Sasaki, Ryohei; Yasuda, Koichi; Abe, Eisuke; Uchida, Nobue; Kawashima, Mitsuhiko; Uno, Takashi; Fujiwara, Masayuki; Shioyama, Yoshiyuki; Kagami, Yoshikazu; Shibamoto, Yuta; Nakata, Kensei; Takada, Yoshie; Kawabe, Tetsuya; Uehara, Kazuyuki; Nibu, Kenichi; Yamada, Syogo

    2012-01-01

    Purpose: The purpose of this study was to elucidate the efficacy and optimal method of radiotherapy in the management of solitary extramedullary plasmacytoma occurring in the head and neck regions (EMPHN). Methods and Materials: Sixty-seven patients (43 male and 24 female) diagnosed with EMPHN between 1983 and 2008 at 23 Japanese institutions were reviewed. The median patient age was 64 years (range, 12–83). The median dose administered was 50 Gy (range, 30–64 Gy). Survival data were calculated by the Kaplan-Meier method. Results: The median follow-up duration was 63 months. Major tumor sites were nasal or paranasal cavities in 36 (54%) patients, oropharynx or nasopharynx in 16 (23%) patients, orbita in 6 (9%) patients, and larynx in 3 (5%) patients. The 5- and 10-year local control rates were 95% and 87%, whereas the 5- and 10-year disease-free survival rates were 56% and 54%, respectively. There were 5 (7.5%), 12 (18%), and 8 (12%) patients who experienced local failure, distant metastasis, and progression to multiple myeloma, respectively. In total, 18 patients died, including 10 (15%) patients who died due to complications from EMPHN. The 5- and 10-year overall survival (OS) rates were 73% and 56%, respectively. Radiotherapy combined with surgery was identified as the lone significant prognostic factor for OS (p = 0.04), whereas age, gender, radiation dose, tumor size, and chemotherapy were not predictive. No patient experienced any severe acute morbidity. Conclusions: Radiotherapy was quite effective and safe for patients with EMPHN. Radiotherapy combined with surgery produced a better outcome according to survival rates. These findings require confirmation by further studies with larger numbers of patients with EMPHN.

  3. Role of radiotherapy fractionation in head and neck cancers (MARCH)

    DEFF Research Database (Denmark)

    Lacas, Benjamin; Bourhis, Jean; Overgaard, Jens

    2017-01-01

    BACKGROUND: The Meta-Analysis of Radiotherapy in squamous cell Carcinomas of Head and neck (MARCH) showed that altered fractionation radiotherapy is associated with improved overall and progression-free survival compared with conventional radiotherapy, with hyperfractionated radiotherapy showing...... the greatest benefit. This update aims to confirm and explain the superiority of hyperfractionated radiotherapy over other altered fractionation radiotherapy regimens and to assess the benefit of altered fractionation within the context of concomitant chemotherapy with the inclusion of new trials. METHODS......: For this updated meta-analysis, we searched bibliography databases, trials registries, and meeting proceedings for published or unpublished randomised trials done between Jan 1, 2009, and July 15, 2015, comparing primary or postoperative conventional fractionation radiotherapy versus altered fractionation...

  4. Grounded theory for radiotherapy practitioners: Informing clinical practice

    International Nuclear Information System (INIS)

    Walsh, N.A.

    2010-01-01

    Radiotherapy practitioners may be best placed to undertake qualitative research within the context of cancer, due to specialist knowledge of radiation treatment and sensitivity to radiotherapy patient's needs. The grounded theory approach to data collection and analysis is a unique method of identifying a theory directly based on data collected within a clinical context. Research for radiotherapy practitioners is integral to role expansion within the government's directive for evidence-based practice. Due to the paucity of information on qualitative research undertaken by radiotherapy radiographers, this article aims to assess the potential impact of qualitative research on radiotherapy patient and service outcomes.

  5. Can field-in-field technique replace wedge filter in radiotherapy treatment planning: a comparative analysis in various treatment sites

    International Nuclear Information System (INIS)

    Prabhakar, R.; Julka, P.K.; Rath, G.K.

    2008-01-01

    The aim of the study was to show whether field-in-field (FIF) technique can be used to replace wedge filter in radiation treatment planning. The study was performed in cases where wedges are commonly used in radiotherapy treatment planning. Thirty patients with different malignancies who received radiotherapy were studied. This includes patients with malignancies of brain, head and neck, breast, upper and lower abdomen. All the patients underwent computed tomography scanning and the datasets were transferred to the treatment planning system. Initially, wedge based planning was performed to achieve the best possible dose distribution inside the target volume with multileaf collimators (Plan1). Wedges were removed from a copy of the same plan and FIF plan was generated (Plan2). The two plans were then evaluated and compared for mean dose, maximum dose, median dose, doses to 2% (D 2 ) and 98% (D 9 8) of the target volume, volume receiving greater than 107% of the prescribed dose (V>107%), volume receiving less than 95% of the prescribed dose (V 2 , V>107% and CI for more of the sites with statistically significant reduction in monitor units. FIF results in better dose distribution in terms of homogeneity in most of the sites. It is feasible to replace wedge filter with FIF in radiotherapy treatment planning.

  6. Propensity Score Matching Analysis of Changes in Alpha-Fetoprotein Levels after Combined Radiotherapy and Transarterial Chemoembolization for Hepatocellular Carcinoma with Portal Vein Tumor Thrombus.

    Directory of Open Access Journals (Sweden)

    Yuri Jeong

    Full Text Available To investigate the value of changes in alpha-fetoprotein (AFP levels for the prediction of radiologic response and survival outcomes in hepatocellular carcinoma (HCC patients with portal vein tumor thrombus (PVTT who received combined treatment of 3-dimensional conformal radiotherapy (3D-CRT and transarterial chemoembolization (TACE.A database of 154 HCC patients with PVTT and elevated AFP levels (>20 ng/mL treated with 3D-CRT and TACE as an initial treatment between August 2002 and August 2008 was retrospectively reviewed. AFP levels were determined 1 month after radiotherapy, and AFP response was defined as an AFP level reduction of >20% from the initial level. Radiologic response, overall survival (OS, and progression-free survival (PFS rates were compared between AFP responders and non-responders. Propensity-score based matching analysis was performed to minimize the effect of potential confounding bias.The median follow-up period was 11.1 months (range, 3.1-82.7 months. In the propensity-score matching cohort (92 pairs, a best radiologic response of CR or PR occurred in more AFP responders than AFP non-responders (41.3% vs. 10.9%, p < 0.001. OS and PFS were also longer in AFP responders than in non-responders (median OS 13.2 months vs. 5.6 months, p < 0.001; median PFS 8.7 months vs. 3.5 months, p < 0.001.AFP response is a significant predictive factor for radiologic response. Furthermore, AFP response is significant for OS and PFS outcomes. AFP evaluation after combined radiotherapy and TACE appears to be a useful predictor of clinical outcomes in HCC patients with PVTT.

  7. Retrospective analysis of self-reporting pain scores and pain management during head and neck IMRT radiotherapy: A single institution experience

    International Nuclear Information System (INIS)

    O'Connor, P.; Bisson, J.; Asplin, P.; Gahir, D.

    2017-01-01

    Aims: Head and neck carcinomas are relatively rare in the United Kingdom with an estimated 9000 cases diagnosed annually. However, pain associated with disease and treatment side effects such as oral mucositis present a major issue for therapy radiographers in providing effective care and maintaining radiotherapy treatment compliance, all factors that can compromise patient outcome if not managed appropriately. Method: This retrospective analysis of self-reporting pain scores collected during a course of radiotherapy aims to assess the perceived pain intensity scores in 30 patients. Data was collected during radiographer review sessions held weekly to determine if any variables to perceived pain scores occurred during a course of radiotherapy. Results: As treatment progressed, the self-reporting pain scores within the cohort increased, in week one the total cohort pain score was 35, this increased to 114 in week 3 and in the final week had totalled 151. An escalation in pain was observed in week 3 of treatment possibly as a result of radiation induced inflammation alongside cytotoxic chemotherapy. Conclusions: The findings of this study provide further evidence to an individualised approach to patient pain relief and providing regular on treatment reviews, thus maintaining patient comfort and ensuring continued treatment compliance. - Highlights: • Pain is an important but too infrequently analysed symptom in head and neck cancer. • As treatment progressed, the self-reporting pain scores within the cohort increased. • These findings provide the rationale for an individualised approach to pain relief. • Ensuring adequate pain control can positively influence continued treatment compliance.

  8. Risk factors of radiation-induced liver disease after three-dimensional conformal radiotherapy for primary liver carcinoma

    International Nuclear Information System (INIS)

    Liang Shixiong; Zhu Xiaodong; Lu Haijie; Pan Chaoyang; Huang Qifang; Li Fuxiang; Wang Anyu; Liang Guoliang; Fu Xiaolong

    2005-01-01

    Objective: To identify the risk factors of radiation-induced liver disease (RILD) after three-dimensional radiotherapy (3DCRT) for primary liver carcinoma (PLC) and the dosimetric threshold of RILD. Methods: Between April 1999 and August 2003, 128 PLC patients who were treated with 3DCRT received a mean dose of 53.6 ± 6.6 Gy with a 4-8 Gy/f, 3f/w, qod regimen. The relation between RILD and the possible clinical factors, such as gender, age, UICC/ AJCC T stage, GTV, HBV status, PTV, TACE, Child-Pugh grade of liver cirrhosis, BED calculated by LQ model and fraction size were analyzed. Among 84 patients who had full dose- volume histogram (DVH) data, the relation between RILD and dosimetric parameters were analyzed. Results: Nineteen patients (14.8%) developed RILD. It was found that T stage, GTV, PTV, Child-Pugh grade of liver cirrhosis and the acute hepatic toxicity proposed by common toxicity criteria version 2.0 (CTC2.0) were correlated with RILD (P=0.024, 0.002, 0.001, 0.000, 0.000, respectively). Multivariate analysis showed that only the Child-Pugh grade of liver cirrhosis was independent factor (P=0.000). The mean liver dose was significantly higher in patients with RILD (P=0.027). In patients with Child-Pugh grade A, V5 (percentage of normal liver volume with radiation dose > 5 Gy), V 10 and V 20 ≤81%, 69% and 42%, mean liver dose ≤28 Gy, RILD was not observed, whereas in patients with Child-Pugh grade B, the possibility of developing RILD was 53.3%(8/15). Conclusions: Comprehensive consideration of T stage, GTV, PTV and Child-Pugh grade of liver cirrhosis, especially the Child-Pugh grade of liver cirrhosis, when planning 3DCRT for PLC, may lower the incidence of RILD. (authors)

  9. The role and strategy of IMRT in radiotherapy of pelvic tumors: Dose escalation and critical organ sparing in prostate cancer

    International Nuclear Information System (INIS)

    Liu, Y.-M.; Shiau, C.-Y.; Lee, M.-L.; Huang, P.-I.; Hsieh, C.-M.; Chen, P.-H.; Lin, Y.-H.; Wang, L.-W.; Yen, S.-H.

    2007-01-01

    Purpose: To investigate the intensity-modulated radiotherapy (IMRT) strategy in dose escalation of prostate and pelvic lymph nodes. Methods and Materials: Plan dosimetric data of 10 prostate cancer patients were compared with two-dimensional (2D) or IMRT techniques for pelvis (two-dimensional whole pelvic radiation therapy [2D-WPRT] or IM-WPRT) to receive 50 Gy or 54 Gy and additional prostate boost by three-dimensional conformal radiation therapy or IMRT (3D-PBRT or IM-PBRT) techniques up to 72 Gy or 78 Gy. Dose-volume histograms (DVHs), normal tissue complication probabilities (NTCP) of critical organ, and conformity of target volume in various combinations were calculated. Results: In DVH analysis, the plans with IM-WPRT (54 Gy) and additional boost up to 78 Gy had lower rectal and bladder volume percentage at 50 Gy and 60 Gy, compared with those with 2D-WPRT (50 Gy) and additional boost up to 72 Gy or 78 Gy. Those with IM-WPRT (54 Gy) also had better small bowel sparing at 30 Gy and 50 Gy, compared with those with 2D-WPRT (50 Gy). In NTCP, those with IM-WPRT and total dose of 78 Gy achieved lower complication rates in rectum and small bowel, compared with those of 2D-WPRT with total dose of 72 Gy. In conformity, those with IM-WPRT had better conformity compared with those with 2D-WPRT with significance (p < 0.005). No significant difference in DVHs, NTCP, or conformity was found between IM-PBRT and 3D-PBRT after IM-WPRT. Conclusions: Initial pelvic IMRT is the most important strategy in dose escalation and critical organ sparing. IM-WPRT is recommended for patients requiring WPRT. There is not much benefit for critical organ sparing by IMRT after 2D-WPRT

  10. Clinical quality standards for radiotherapy

    Science.gov (United States)

    2012-01-01

    Aim of the study The technological progress that is currently being witnessed in the areas of diagnostic imaging, treatment planning systems and therapeutic equipment has caused radiotherapy to become a high-tech and interdisciplinary domain involving staff of various backgrounds. This allows steady improvement in therapy results, but at the same time makes the diagnostic, imaging and therapeutic processes more complex and complicated, requiring every stage of those processes to be planned, organized, controlled and improved so as to assure high quality of services provided. The aim of this paper is to present clinical quality standards for radiotherapy as developed by the author. Material and methods In order to develop the quality standards, a comparative analysis was performed between European and Polish legal acts adopted in the period of 1980-2006 and the universal industrial ISO 9001:2008 standard, defining requirements for quality management systems, and relevant articles published in 1984-2009 were reviewed, including applicable guidelines and recommendations of American, international, European and Polish bodies, such as the American Association of Physicists in Medicine (AAPM), the European Society for Radiotherapy & Oncology (ESTRO), the International Atomic Energy Agency (IAEA), and the Organisation of European Cancer Institutes (OECI) on quality assurance and management in radiotherapy. Results As a result, 352 quality standards for radiotherapy were developed and categorized into the following three groups: 1 – organizational standards; 2 – physico-technical standards and 3 – clinical standards. Conclusion Proposed clinical quality standards for radiotherapy can be used by any institution using ionizing radiation for medical purposes. However, standards are of value only if they are implemented, reviewed, audited and improved, and if there is a clear mechanism in place to monitor and address failure to meet agreed standards. PMID:23788854

  11. Clinical trials radiotherapy treatment plan review software : is this the first quantified assessment

    International Nuclear Information System (INIS)

    Hatton, J.A.; Cornes, D.A.

    2011-01-01

    Full text: Clinical trials require robust quality assurance (QA) procedures to ensure commonality of all treatments, with independent reviews to assess compliance with trial protocols. All clinical trials tools, including QA software, require testing for validity and reliability. enabling inter- and intra-trial comparison. Unlike clinical radiotherapy treatment planning (RTP) systems, review software has no published guidelines. This study describes the design and development of a test suite to quantify the performance of review software in TROG clinical trials. Test areas are image handling and reconstruction; geometric accuracy; dosimetric accuracy; dose-volume histogram (DVH) calculation; display of plan parameters. TROG have developed tests for commissioning plan review software, assessed with SWAN 2.3, and CMS Elekta FocalPro. While image handling tests were based on published guidelines for RTP systems, dosimetric tests used the TROG QA case review requirements. Treatment plans represented systems of all manufacturers (Pinnacle, Eclipse, Xio and Oncentra) used in Australasian centres. The test suite identified areas for SW A software development, including the DVH algorithm, changed to reduce calculation time. Results, in Fig. I, for known volumes of varying shapes and sizes, demonstrate differences between SWAN 2.1 and 2.3 when compared with Eclipse. Liaison with SWAN programmers enabled re-instatement of 2.1 algorithm. The test suite has quantified the RTP review software, prioritised areas for development with the programmers, and improved the user experience.

  12. 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....

  13. Preoperative radiotherapy with high dose rate brachytherapy in the treatment of stage IIB cervix cancer. A retrospective analysis of histological specimens

    International Nuclear Information System (INIS)

    Ferrigno, Robson; Trippe, N; Novaes, P.E.; Brandani, I.B.; Hanriot, R.; Souza, L.M.; Pellizzon, A.C.; Salvajoli, J.V.; Baraldi, H.E.; Maia, M.A.; Fogaroli, R.C.

    1996-01-01

    Purpose/Objective: To evaluate the histological specimens of the stage IIB cervix cancer patients who were treated by preoperative radiotherapy with external beam radiotherapy (EBRT) and high dose rate (HDR) brachytherapy. Materials and Methods: From August 1992 to August 1995, 32 patients with stage IIB cervix cancer were underwent to preoperative radiotherapy. All patients received EBRT at the whole pelvis with total dose of 45Gy in 25 fractions of 1,8Gy through a 4 MV linear accelerator. The HDR brachytherapy was realized through a Micro-Selectron device, working with Iridium-192 with initial activity of 10 Ci. The prescribed dose was 6,0Gy at point A, defined by the Manchester, system in 2 weekly insertions during the course of EBRT. The insertions were done by the Fletcher colpostats in association with intrauterine tandem. Four to six weeks after the end of radiotherapy, the patients were underwent to Total Hysterectomy and Salpingoforectomy through Piver second level technique. The uterine specimens were histologically analysed with attention to residual disease at the cervix and lymph nodes status. Results: The histological analysis showed that 19 (59,4%) patients had no residual tumor at the cervix while 13 (40,6%) had microscopic residual tumor. The lymph nodes were negative in 30 (93,8%) patients and positive in 2 (6,3%). All positive lymph nodes patients also had microscopic residual tumor at the cervix. With the follow up ranging from six to 42 months and medium of 21 months, 29 (90,6%) patients are alive with no evidence of disease, one (5,6%) is alive with local recurrence and two (6,2%) have died due to the progression of local disease. Of the 19 patients with negative specimens, 18 (94,7%) are alive with no evidence of disease and of the 13 patients with positive specimens, 11 (84,6%) are alive with no evidence of disease. Local recurrence occurred in two patients with positive specimens and in one with negative. These differences are not

  14. The effect on the radiotherapy for cervical cancer patients quality of life and the related health education

    International Nuclear Information System (INIS)

    Gao Xinli

    2012-01-01

    Radiotherapy is an important means of cervical cancer, due to the specificity of tumor site and side effect of radiotherapy, lack of knowledge of radiotherapy for patients and relatives about the disease, It is particularly important during radiotherapy on health education. By the analysis of radiotherapy for cervical cancer patients quality of life, it is the purpose of patients during the period of radiotherapy of whole course health education. Including before radiotherapy, radiotherapy in health education and the guide of the leaving hospital. In order to improve the compliance of patients, reduce the complications. Further it is improved the clinical treatment effect. (author)

  15. Adjuvant radiotherapy for stage I endometrial cancer.

    Science.gov (United States)

    Kong, A; Johnson, N; Cornes, P; Simera, I; Collingwood, M; Williams, C; Kitchener, H

    2007-04-18

    The role of adjuvant radiotherapy (both pelvic external beam radiotherapy and vaginal intracavity brachytherapy) in stage I endometrial cancer following total abdominal hysterectomy and bilateral salpingo-oophorectomy (TAH and BSO) remains unclear. To assess the efficacy of adjuvant radiotherapy following surgery for stage I endometrial cancer. The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, CancerLit, Physician Data Query (PDQ) of National Cancer Institute. Handsearching was also carried out where appropriate. Randomised controlled trials (RCTs) which compared adjuvant radiotherapy versus no radiotherapy following surgery for patients with stage I endometrial cancer were included. Quality of the studies was assessed and data collected using a predefined data collection form. The primary endpoint was overall survival. Secondary endpoints were locoregional recurrence, distant recurrence and endometrial cancer death. Data on quality of life (QOL) and morbidity were also collected. A meta-analysis on included trials was performed using the Cochrane Collaboration Review Manager Software 4.2. The meta-analysis was performed on four trials (1770 patients). The addition of pelvic external beam radiotherapy to surgery reduced locoregional recurrence, a relative risk (RR) of 0.28 (95% confidence interval (CI) 0.17 to 0.44, p ASTEC; Lukka) are awaited. External beam radiotherapy carries a risk of toxicity and should be avoided in stage 1 endometrial cancer patients with no high risk factors.

  16. Therapeutic Results of Radiotherapy in Rectal Carcinoma -Comparison of Sandwich Technique Radiotherapy with Postoperative Radiotherapy

    International Nuclear Information System (INIS)

    Huh, Gil Cha; Suh, Hyun Suk; Lee, Hyuk Sang; Kim, Re Hwe; Kim, Chul Soo; Kim, Hong Yong; Kim, Sung Rok

    1996-01-01

    Purpose : To evaluate the potential advantage for 'sandwich' technique radiotherapy compared to postoperative radiotherapy in respectable rectal cancer. Between January 1989 and May 1994, 60 patients with respectable rectal cancer were treated at Inje University Seoul and Sanggye Paik Hospital.Fifty one patients were available for analysis : 20 patients were treated with sandwich technique radiotherapy and 31 patients were treated with postoperative radiotherapy. In sandwich technique radiotherapy(RT), patients were treated with preoperative RT 1500 cGy/5fx followed by immediate curative resection. Patients staged as Astler-Coller B2, C were considered for postoperative RT with 2500-4500 cGy. In postoperative RT, total radiation dose of 4500-6120 cGy, 180 cGy daily at 4-6 weeks was delivered. Patients were followed for median period of 25 months. Results : The overall 5-year survival rates for sandwich technique RT group and postoperative RT group were 60% and 71%, respectively(p>0.05). The 5-year disease free survival rates for each group were 63%. There was no difference in local failure rate between two groups(11% versus 7%). Incidence of distant metastasis was 11%(2/20) in the sandwich technique RT group and 20%(6/31) in the postoperative RT group(p>0.05). The frequencies of acute and chronic complications were comparable in both groups. Conclusion : The sandwich technique radiotherapy group shows local recurrence and survival similar to those of postoperative RT alone group but reduced distant metastasis compared to postoperative RT group. But long term follow-up and large number of patients is needed to make an any firm conclusion regarding the value of this sandwich technique RT

  17. Costing in Radiotherapy. Chapter 18

    International Nuclear Information System (INIS)

    Zubizarreta, E.; Lievens, Y.; Levin, V.C.; Van Der Merwe, D.

    2017-01-01

    The available literature on the cost of radiotherapy yields a large variation in data related to the specifics of the methodology used (the viewpoint of the analysis, time frame, health care system, etc.) and to the cost components and radiotherapy activities included. To overcome this difficulty, the reimbursement paid by medical insurance is commonly used as a proxy for the actual radiotherapy costs. Costs, however, generally bear little or no resemblance to charges, as the latter also include allowances for non-capacity use and profit margins. Accurate resource cost data are therefore more valid and should ideally be used in the context of economic evaluations and public health provisions. In addition to the theoretical problems related to obtaining accurate costs, it is difficult to interpret cost data across country borders because of differences in economics. If this is already the case for high income countries, using these cost data for low and middle income countries (LMICs) is even more problematic. Thus, there clearly is a need for calculations performed from the viewpoint of LMICs to prevent misapprehensions based on conclusions derived from data from their high income counterparts. The IAEA endeavours to assist Member States in accumulating appropriate and sufficient cost data for the initiation or expansion of radiation oncology services. Although relatively simple and easy to understand, the IAEA has found that in many countries where it has been involved in the establishment of new radiotherapy departments, the basic principles of cost calculation for radiotherapy facilities were not followed by the local planners. Radiotherapy needs careful planning, organization and a strong quality assurance (QA) programme in order to deliver safe treatments, due to the complexity of the planning and treatment process and the possibility of systematic errors. Administrators should be aware that the cost of building a radiotherapy facility and buying machines

  18. Comparative analysis of the effects of belly board and bladder distension in postoperative radiotherapy of rectal cancer patients

    International Nuclear Information System (INIS)

    Kim, T.H.; Kim, D.Y.; Cho, K.H.

    2005-01-01

    Purpose: To compare the effect of reducing the irradiated small-bowel volume with the use of belly board, bladder distension or both methods combined, in patients with rectal cancer undergoing postoperative pelvic radiotherapy. Patients and methods: This study enrolled 20 consecutive patients with rectal cancer who were scheduled to receive postoperative pelvic radiotherapy. All patients underwent four sets of CT scans under four different methods as follows: group I: empty bladder without the use of a belly board; group II: empty bladder with the use of a belly board; group III: bladder distension without the use of a belly board; group IV: bladder distension with the use of a belly board. The conventional three-field treatment plan was made using a three-dimensional treatment planning system. The irradiated small-bowel volume was calculated at 10% intervals from 10% to 100% of the prescribed dose. Results: The volume of the irradiated small bowel decreased in the order of group I, group II, group III, and group IV at all dose levels (p 3 (33.9±12.9%) in group II, 76.6±30.5 cm 3 (55.1±17.8%) in group III, and 98.5±36.7 cm 3 (70.7±14.5%) in group IV. Conclusion: Bladder distension was a more effective method than the belly board for reducing the irradiated small-bowel volume in postoperative pelvic radiotherapy of rectal cancer patients. The combination of the belly board and bladder distension showed an additive effect and was the most effective method for reducing the irradiated small-bowel volume. (orig.)

  19. Metastases radiotherapy of malignant melanomas in soft tissues: analysis of sixty patients series treated between the 1. of january 1990 and the 31. december of 1996

    International Nuclear Information System (INIS)

    Meunier-Olympie, O

    1998-01-01

    The radiotherapy efficiency is still undervalued in the therapeutic taking charge of the malignant melanoma. Our series with its heterogeneity has authorized an only mono factorial analysis. The data in literature and our personal experience give a better efficiency of the strong unitary doses in term of local control. The accuracy of irradiation must allow to reduce the importance of after-effects that can be necessary to the local control and then to the survival. for the future, an increasing of of the applied unitary doses, by taking into account the localisation, the tumoral volume and the therapeutic objective, would allow to improve the efficiency of this treatment. In The particular indication of inoperable Dubreuilh melanosis, it could be an alternative to the surgery. The results of a complementary radiotherapy, after a radical surgery of secondary localisation are very encouraging. Its contribution in adjuvant treatment of recurrence or primitive lesions with high risks would deserve to be evaluated in the frame of well defined and randomized tests. (N.C.)

  20. Optimisation of chemotherapy and radiotherapy for untreated Hodgkin lymphoma patients with respect to second malignant neoplasms, overall and progression-free survival: individual participant data analysis.

    Science.gov (United States)

    Franklin, Jeremy; Eichenauer, Dennis A; Becker, Ingrid; Monsef, Ina; Engert, Andreas

    2017-09-13

    Efficacy and the risk of severe late effects have to be well-balanced in treatment of Hodgkin lymphoma (HL). Late adverse effects include secondary malignancies which often have a poor prognosis. To synthesise evidence on the risk of secondary malignancies after current treatment approaches comprising chemotherapy and/or radiotherapy, we performed a meta-analysis based on individual patient data (IPD) from patients treated for newly diagnosed HL. We investigated several questions concerning possible changes in the risk of secondary malignancies when modifying chemotherapy or radiotherapy (omission of radiotherapy, reduction of the radiation field, reduction of the radiation dose, use of fewer chemotherapy cycles, intensification of chemotherapy). We also analysed whether these modifications affect progression-free survival (PFS) and overall survival (OS). We searched MEDLINE and Cochrane CENTRAL trials databases comprehensively in June 2010 for all randomised trials in HL since 1984. Key international trials registries were also searched. The search was updated in March 2015 without collecting further IPD (one further eligible study found) and again in July 2017 (no further eligible studies). We included randomised controlled trials (RCTs) for untreated HL patients which enrolled at least 50 patients per arm, completed recruitment by 2007 and performed a treatment comparison relevant to our objectives. Study groups submitted IPD, including age, sex, stage and the outcomes secondary malignant neoplasm (SMN), OS and PFS as time-to-event data. We meta-analysed these data using Petos method (SMN) and Cox regression with inverse-variance pooling (OS, PFS) for each of the five study questions, and performed subgroup and sensitivity analyses to assess the applicability and robustness of the results. We identified 21 eligible trials and obtained IPD for 16. For four studies no data were supplied despite repeated efforts, while one study was only identified in 2015 and IPD

  1. Impact of BCL2 and p53 on postmastectomy radiotherapy response in high-risk breast cancer. A subgroup analysis of DBCG82 b&c

    DEFF Research Database (Denmark)

    Kyndi, Marianne; Sørensen, Flemming Brandt; Knudsen, Helle

    2008-01-01

    -Meier probability plots showed a significantly improved overall survival after PMRT for the BCL2 positive subgroup, whereas practically no survival improvement was seen after PMRT for the BCL2 negative subgroup. In multivariate analysis of OS, however, no significant interaction was found between BCL2......PURPOSE: To examine p53 and BCL2 expression in high-risk breast cancer patients randomized to postmastectomy radiotherapy (PMRT). PATIENTS AND METHODS: The present analysis included 1 000 of 3 083 high-risk breast cancer patients randomly assigned to PMRT in the DBCG82 b&c studies. Tissue...... tests, Kaplan-Meier probability plots, Log-rank test, and Cox univariate and multivariate regression analyses. RESULTS: p53 accumulation was not significantly associated with increased overall mortality, DM or LRR probability in univariate or multivariate Cox regression analyses. Kaplan...

  2. Impact of BCL2 and p53 on postmastectomy radiotherapy response in high-risk breast cancer. A subgroup analysis of DBCG82 b

    DEFF Research Database (Denmark)

    Kyndi, M.; Sorensen, F.B.; Alsner, J.

    2008-01-01

    -Meier probability plots showed a significantly improved overall survival after PMRT for the BCL2 positive subgroup, whereas practically no survival improvement was seen after PMRT for the BCL2 negative subgroup. In multivariate analysis of OS, however, no significant interaction was found between BCL2......Purpose. To examine p53 and BCL2 expression in high-risk breast cancer patients randomized to postmastectomy radiotherapy (PMRT). Patients and methods. The present analysis included 1000 of 3 083 high-risk breast cancer patients randomly assigned to PMRT in the DBCG82 b&c studies. Tissue microarray......, Kaplan-Meier probability plots, Log-rank test, and Cox univariate and multivariate regression analyses. Results. p53 accumulation was not significantly associated with increased overall mortality, DM or LRR probability in univariate or multivariate Cox regression analyses. Kaplan-Meier probability plots...

  3. A strategy to correct for intrafraction target translation in conformal prostate radiotherapy: Simulation results

    International Nuclear Information System (INIS)

    Keall, P. J.; Lauve, A. D.; Hagan, M. P.; Siebers, J. V.

    2007-01-01

    A strategy is proposed in which intrafraction internal target translation is corrected for by repositioning the multileaf collimator position aperture to conform to the new target pose in the beam projection, and the beam monitor units are adjusted to account for the change in the geometric relationship between the target and the beam. The purpose of this study was to investigate the dosimetric stability of the prostate and critical structures in the presence of internal target translation using the dynamic compensation strategy. Twenty-five previously treated prostate cancer patients were replanned using a four-field conformal technique to deliver 72 Gy to 95% of the planning target volume (PTV). Internal translation was introduced by displacing the prostate PTV (no rotation or deformation was considered). Thirty-six randomly selected isotropic displacements of magnitude 0.5, 1.0, 1.5 and 2.0 cm were sampled for each patient, for a total of 3600 errors. Due to their anatomic relation to the prostate, the rectum and bladder contours were also moved with the same magnitude and direction as the prostate. The dynamic compensation strategy was used to correct each of these errors by conforming the beam apertures to the new target pose and adjusting the monitor units using inverse-square and off-axis factor corrections. The dynamic compensation strategy plans were then compared to the original treatment plans via dose-volume histogram (DVH) analysis. Changes of more than 5% of the prescription dose (3.6 Gy) were deemed clinically significant. Compared to the original treatment plans, the dynamic compensation strategy produced small discrepancies in isodose distributions and DVH analyses for all structures considered apart from the femoral heads. These differences increased with the magnitude of the internal motion. Coverage of the PTV was excellent: D 5 , D 95 , and D mean were not increased or decreased by more than 5% of the prescription dose for any of the 3600

  4. The metabolic radiotherapy. La radiotherapie metabolique

    Energy Technology Data Exchange (ETDEWEB)

    Begon, F.; Gaci, M. (Centre Hospitalier Universitaire, 86 - Poitiers (France))

    In this article, the authors recall the principles of the metabolic radiotherapy and present these main applications in the treatment of thyroid cancers, hyperthyroidism, polycythemia, arthritis, bone metastases, adrenergic neoplasms. They also present the radioimmunotherapy.

  5. Dose-volume histogram analysis of hepatic toxicity related to carbon ion radiation therapy of hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Yasuda, Shigeo; Kato, Hirotoshi; Tsujii, Hitohiko; Mizoe, Junetsu

    2005-01-01

    The purpose of this study is to analyze the correlation of hepatic toxicity with dose-volume factors of carbon ion radiotherapy in the liver. Forty-nine patients with hepatocellular carcinoma were treated with carbon ion radiotherapy delivered in 4 fractions over 4 to 7 days. Six patients received a total dose of 48 GyE and 43 received 52.8 GyE. The correlation of various blood biochemistry data with dose-volume histogram (DVH) data in non-cancerous liver were evaluated. The strongest significant correlation was seen between percent volume of non-cancerous liver with radiation dose more than 11 GyE (V 11 GyE ) and elevation of serum glutamic oxaloacetic transaminase (GOT) level as early adverse response after carbon ion beam radiation therapy (p=0.0003). In addition, significant correlation between DVH data and change of several other blood biochemistry data were also revealed in early phase. In late phase after carbon ion radiotherapy, the strongest significant correlation was seen between decrease of platelet count and V 26GyE (p=0.015). There was no significant correlation between other blood biochemistry data and DVH data in the late phase. It was suggested that dose-volume factors of carbon ion radiotherapy influenced only transient aggravation of liver function, which improved in the long term after irradiation. (author)

  6. Frequency filtering based analysis on the cardiac induced lung tumor motion and its impact on the radiotherapy management

    International Nuclear Information System (INIS)

    Chen, Ting; Qin, Songbing; Xu, Xiaoting; Jabbour, Salma K.; Haffty, Bruce G.; Yue, Ning J.

    2014-01-01

    Purpose/objectives: Lung tumor motion may be impacted by heartbeat in addition to respiration. This study seeks to quantitatively analyze heart-motion-induced tumor motion and to evaluate its impact on lung cancer radiotherapy. Methods/materials: Fluoroscopy images were acquired for 30 lung cancer patients. Tumor, diaphragm, and heart were delineated on selected fluoroscopy frames, and their motion was tracked and converted into temporal signals based on deformable registration propagation. The clinical relevance of heart impact was evaluated using the dose volumetric histogram of the redefined target volumes. Results: Correlation was found between tumor and cardiac motion for 23 patients. The heart-induced motion amplitude ranged from 0.2 to 2.6 mm. The ratio between heart-induced tumor motion and the tumor motion was inversely proportional to the amplitude of overall tumor motion. When the heart motion impact was integrated, there was an average 9% increase in internal target volumes for 17 patients. Dose coverage decrease was observed on redefined planning target volume in simulated SBRT plans. Conclusions: The tumor motion of thoracic cancer patients is influenced by both heart and respiratory motion. The cardiac impact is relatively more significant for tumor with less motion, which may lead to clinically significant uncertainty in radiotherapy for some patients

  7. Evaluation of the Usefulness of Restricted Respiratory Period at the Time of Radiotherapy for Non-Small Cell Lung Cancer Patient

    Energy Technology Data Exchange (ETDEWEB)

    Park, So Yeon; Ahn, Jong Ho; Kim, Yung Il; Kim, Jin Man; Choi, Byung Ki; Pyo, Hong Ryul; Song, Ki Won [Dept. of Radiation Oncology, Samsung Medical Center, Seoul (Korea, Republic of); Suh, Jung Min [Dept. of Radiological Science, Daewon University Colloge, Jecheon (Korea, Republic of)

    2012-09-15

    It is essential to minimize the movement of tumor due to respiratory movement at the time of respiration controlled radiotherapy of non-small cell lung cancer patient. Accordingly, this Study aims to evaluate the usefulness of restricted respiratory period by comparing and analyzing the treatment plans that apply free and restricted respiration period respectively. After having conducted training on 9 non-small cell lung cancer patients (tumor n=10) from April to December 2011 by using 'signal monitored-breathing (guided- breathing)' method for the 'free respiratory period' measured on the basis of the regular respiratory period of the patents and 'restricted respiratory period' that was intentionally reduced, total of 10 CT images for each of the respiration phases were acquired by carrying out 4D CT for treatment planning purpose by using RPM and 4-dimensional computed tomography simulator. Visual gross tumor volume (GTV) and internal target volume (ITV) that each of the observer 1 and observer 2 has set were measured and compared on the CT image of each respiratory interval. Moreover, the amplitude of movement of tumor was measured by measuring the center of mass (COM) at the phase of 0% which is the end-inspiration (EI) and at the phase of 50% which is the end-exhalation (EE). In addition, both observers established treatment plan that applied the 2 respiratory periods, and mean dose to normal lung (MDTNL) was compared and analyzed through dose-volume histogram (DVH). Moreover, normal tissue complication probability (NTCP) of the normal lung volume was compared by using dose-volume histogram analysis program (DVH analyzer v.1) and statistical analysis was performed in order to carry out quantitative evaluation of the measured data. As the result of the analysis of the treatment plan that applied the 'restricted respiratory period' of the observer 1 and observer 2, there was reduction rate of 38.75% in the 3-dimensional

  8. Evaluation of the Usefulness of Restricted Respiratory Period at the Time of Radiotherapy for Non-Small Cell Lung Cancer Patient

    International Nuclear Information System (INIS)

    Park, So Yeon; Ahn, Jong Ho; Kim, Yung Il; Kim, Jin Man; Choi, Byung Ki; Pyo, Hong Ryul; Song, Ki Won; Suh, Jung Min

    2012-01-01

    It is essential to minimize the movement of tumor due to respiratory movement at the time of respiration controlled radiotherapy of non-small cell lung cancer patient. Accordingly, this Study aims to evaluate the usefulness of restricted respiratory period by comparing and analyzing the treatment plans that apply free and restricted respiration period respectively. After having conducted training on 9 non-small cell lung cancer patients (tumor n=10) from April to December 2011 by using 'signal monitored-breathing (guided- breathing)' method for the 'free respiratory period' measured on the basis of the regular respiratory period of the patents and 'restricted respiratory period' that was intentionally reduced, total of 10 CT images for each of the respiration phases were acquired by carrying out 4D CT for treatment planning purpose by using RPM and 4-dimensional computed tomography simulator. Visual gross tumor volume (GTV) and internal target volume (ITV) that each of the observer 1 and observer 2 has set were measured and compared on the CT image of each respiratory interval. Moreover, the amplitude of movement of tumor was measured by measuring the center of mass (COM) at the phase of 0% which is the end-inspiration (EI) and at the phase of 50% which is the end-exhalation (EE). In addition, both observers established treatment plan that applied the 2 respiratory periods, and mean dose to normal lung (MDTNL) was compared and analyzed through dose-volume histogram (DVH). Moreover, normal tissue complication probability (NTCP) of the normal lung volume was compared by using dose-volume histogram analysis program (DVH analyzer v.1) and statistical analysis was performed in order to carry out quantitative evaluation of the measured data. As the result of the analysis of the treatment plan that applied the 'restricted respiratory period' of the observer 1 and observer 2, there was reduction rate of 38.75% in the 3-dimensional direction movement of the tumor in

  9. Radiotherapy of chondrosarcoma of bone

    International Nuclear Information System (INIS)

    Harwood, A.R.; Krajbich, J.I.; Fornasier, V.L.

    1980-01-01

    A retrospective analysis of 31 cases of chondrosarcoma of bone treated by radiotherapy is presented. In comparison with other large series, our group of patients were found to have been unfavourably selected with respect to the known prognostic factors: histology site, adequacy of operative treatment, and presenting symptoms. Twelve patients with primary chondrosarcoma were radically irradiated; 6 of these 12 have been alive and well without tumor for periods ranging from three and a half to 16 years and 3 of these are alive and well for 15 years or more following radiotherapy. The other 6 patients responded or desease stabilized following radiotherapy for periods ranging from 16 months to eight years. One poorly diffe