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Aarau, Switzerland

Mounessi F.S.,University of Munster | Lehrich P.,University of Munster | Haverkamp U.,University of Munster | Willich N.,University of Munster | And 2 more authors.
Strahlentherapie und Onkologie | Year: 2013

Purpose: The goal of the present work was to assess the potential advantage of intensity-modulated radiotherapy (IMRT) over three-dimensional conformal radiotherapy (3D-CRT) planning in pelvic Ewing's sarcoma. Patients and methods: A total of 8 patients with Ewing sarcoma of the pelvis undergoing radiotherapy were analyzed. Plans for 3D-CRT and IMRT were calculated for each patient. Dose coverage of the planning target volume (PTV), conformity and homogeneity indices, as well as further parameters were evaluated. Results: The average dose coverage values for PTV were comparable in 3D-CRT and IMRT plans. Both techniques had a PTV coverage of V95 > 98 % in all patients. Whereas the IMRT plans achieved a higher conformity index compared to the 3D-CRT plans (conformity index 0.79 ± 0.12 vs. 0.54 ± 0.19, p = 0.012), the dose distribution across the target volumes was less homogeneous with IMRT planning than with 3D-CRT planning. This difference was statistically significant (homogeneity index 0.11 ± 0.03 vs. 0.07 ± 0.0, p = 0.035). For the bowel, Dmean and D1%, as well as V 2 to V60 were reduced in IMRT plans. For the bladder and the rectum, there was no significant difference in Dmean. However, the percentages of volumes receiving at least doses of 30, 40, 45, and 50 Gy (V30 to V50) were lower for the rectum in IMRT plans. The volume of normal tissue receiving at least 2 Gy (V2) was significantly higher in IMRT plans compared with 3D-CRT, whereas at high dose levels (V30) it was significantly lower. Conclusion: Compared to 3D-CRT, IMRT showed significantly better results regarding dose conformity (p = 0.012) and bowel sparing at dose levels above 30 Gy (p = 0.012). Thus, dose escalation in the radiotherapy of pelvic Ewing's sarcoma can be more easily achieved using IMRT. © 2013 Urban & Vogel. Source


Kriz J.,University of Cologne | Kriz J.,University Hospital Muenster | Eich H.T.,University Hospital Muenster | Mucke R.,Lippe Hospital | And 6 more authors.
Anticancer Research | Year: 2012

Background: Giant cell tumor of the bone (GCTB) is a benign or sometimes semi-malignant neoplasm accounting for 5% of all primary bone tumors. This type of tumor has been historically considered as radioresistant, but nowadays radiotherapy (RT) is used in unresectable, recurrent or incompletely resected cases. Since the value of RT is not well defined, a national cohort study was conducted. Patients and Methods: Six German institutions collected data from 35 patients treated during the last 35 years and analyzed them. Results: From 1975-2010 16 male and 19 female patients with 39 lesions were irradiated for GCTB. The median age was 30 years and the median followup 65 months. Nineteen patients had undergone RT for recurrent or unresectable disease and 16 patients for nonin- sano resection. The actuarial 5-year overall and disease-free survival rates were 90% and 59%, respectively. Conclusion: RT is an easy, safe and effective method for the treatment of GCTB. It may provide an attractive alternative to mutilating surgery. Source


Srivastava A.,Medicity | Datta N.R.,Center for Radiation Oncology
World Journal of Clinical Oncology | Year: 2014

Brachytherapy forms an integral part of the radiation therapy in cancer cervix. The dose prescription for intracavitary brachytherapy (ICBT) in cancer cervix is based on Tod and Meredith's point A and has been in practice since 1938. This was proposed at a time when accessibility to imaging technology and dose computation facilities was limited. The concept has been in practice worldwide for more than half a century and has been the fulcrum of all ICBT treatments, strategies and outcome measures. The method is simple and can be adapted by all centres practicing ICBT in cancer cervix. However, with the widespread availability of imaging techniques, clinical use of different dose-rates, availability of a host of applicators fabricated with image compatible materials, radiobiological implications of dose equivalence and its impact on tumour and organs at risk; more and more weight is being laid down on individualised image based brachytherapy. Thus, computed tomography, magnetic-resonance imaging and even positron emission computerized tomography along with brachytherapy treatment planning system are being increasingly adopted with promising outcomes. The present article reviews the evolution of dose prescription concepts in ICBT in cancer cervix and brings forward the need for image based brachytherapy to evaluate clinical outcomes. As is evident, a gradual transition from "point" based brachytherapy to "profile" based image guided brachytherapy is gaining widespread acceptance for dose prescription, reporting and outcome evaluation in the clinical practice of ICBT in cancer cervix. © 2014 Baishideng Publishing Group Inc. All rights reserved. Source


Datta N.R.,Kantonsspital Aarau AG | Puric E.,Kantonsspital Aarau AG | Schneider R.,Paul Scherrer Institute | Weber D.C.,Paul Scherrer Institute | And 4 more authors.
International Journal of Hyperthermia | Year: 2014

Hyperthermia has been conventionally used in conjunction with photon beam irradiation. With a gradual increase in particle therapy facilities worldwide, this paper explores the physical, thermal and radiobiological implications of using a combination of hyperthermia with proton beam therapy. Hyperthermia is known to exhibit radiobiological features similar to those of high linear energy transfer radiation. Protons have many of the physical dose distribution properties of 12C ion therapy. Thus, the thermo-radiobiological advantages of hyperthermia coupled with the physical dose distribution advantages of proton beams could possibly mimic 12C ion therapy. © 2014 Informa UK Ltd. Source


Datta N.R.,Center for Radiation Oncology | Puric E.,Center for Radiation Oncology | Klingbiel D.,Swiss Group for Clinical Cancer Research | Gomez S.,Center for Radiation Oncology | And 2 more authors.
International Journal of Radiation Oncology Biology Physics | Year: 2016

Purpose: To conduct a systematic review and meta-analysis to evaluate the outcome of hyperthermia (HT) and radiation therapy (RT) in locally recurrent breast cancers (LRBCs). Methods and Materials: A total of 708 abstracts were screened from 8 databases according to the PRISMA guidelines. Single-arm and 2-arm studies, treating LRBCs with HT and RT but without surgery (for local recurrence) or concurrent chemotherapy were considered. The evaluated endpoint was complete response (CR). Results: Thirty-one full text articles, pertaining to 34 studies, were shortlisted for the meta-analysis. Eight were 2-arm (randomized, n=5; nonrandomized, n=3), whereas 26 were single-arm studies. In all, 627 patients were enrolled in 2-arm and 1483 in single-arm studies. Patients were treated with a median of 7 HT sessions, and an average temperature of 42.5°C was attained. Mean RT dose was 38.2 Gy (range, 26-60 Gy). Hyperthermia was most frequently applied after RT. In the 2-arm studies, a CR of 60.2% was achieved with RT + HT versus 38.1% with RT alone (odds ratio 2.64, 95% confidence interval [CI] 1.66-4.18, P<.0001). Risk ratio and risk difference were 1.57 (95% CI 1.25-1.96, P<.0001) and 0.22 (95% CI 0.11-0.33, P<.0001), respectively. In 26 single-arm studies, RT + HT attained a CR of 63.4% (event rate 0.62, 95% CI 0.57-0.66). Moreover, 779 patients had been previously irradiated (696 from single-arm and 83 from 2-arm studies). A CR of 66.6% (event rate 0.64, 95% CI 0.58-0.70) was achieved with HT and reirradiation (mean ± SD dose: 36.7 ± 7.7 Gy). Mean acute and late grade 3/4 toxicities with RT + HT were 14.4% and 5.2%, respectively. Conclusions: Thermoradiation therapy enhances the likelihood of CR rates in LRBCs over RT alone by 22% with minimal acute and late morbidities. For even those previously irradiated, reirradiation with HT provides locoregional control in two-thirds of the patients. Thermoradiation therapy could therefore be considered as an effective and safe palliative treatment option for LRBCs. © 2016 Elsevier Inc. Source

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