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Bellavita R.,University of Perugia | Bellavita R.,Institute of Radiation Oncology | Massetti M.,University of Perugia | Abraha I.,University of Perugia | And 7 more authors.
International Journal of Radiation Oncology Biology Physics | Year: 2012

Purpose: To evaluate outcome and toxicity of high-dose conformal radiotherapy (RT) after radical prostatectomy. Methods and Materials: Between August 1998 and December 2007, 182 consecutive patients with positive resection margins and/or pT3-4, node-negative prostate adenocarcinoma underwent postoperative conformal RT. The prescribed median dose to the prostate/seminal vesicle bed was 66.6 Gy (range 50-70). Hormone therapy (a luteinizing hormone-releasing hormone analogue and/or antiandrogen) was administered to 110/182 (60.5%) patients with high-risk features. Biochemical relapse was defined as an increase of more than 0.2 ng/mL over the lowest postoperative prostate-specific antigen (PSA) value measured on 3 occasions, each at least 2 weeks apart. Results: Median follow-up was 55.6 months (range 7.6-141.9 months). The 3- and 5-year probability of biochemical relapse-free survival were 87% and 81%, respectively. In univariate analysis, more advanced T stages, preoperative PSA values ≥10 ng/mL, and RT doses <70 Gy were significant factors for biochemical relapse. Pre-RT PSA values >0.2 ng/mL were significant for distant metastases. In multivariate analysis, risk factors for biochemical relapse were higher preoperative and pre-RT PSA values, hormone therapy for under 402 days and RT doses of <70 Gy. Higher pre-RT PSA values were the only independent predictor of distant metastases. Acute genitourinary (GU) and gastrointestinal (GI) toxicities occurred in 72 (39.6%) and 91 (50%) patients, respectively. There were 2 cases of Grade III GI toxicity but no cases of Grade IV. Late GU and GI toxicities occurred in 28 (15.4%) and 14 (7.7%) patients, respectively: 11 cases of Grade III toxicity: 1 GI (anal stenosis) and 10 GU, all urethral strictures requiring endoscopic urethrotomy. Conclusions: Postoperative high-dose conformal RT in patients with high-risk features was associated with a low risk of biochemical relapse as well as minimal morbidity. © 2012 Elsevier Inc.

Nagata Y.,Hiroshima University | Wulf J.,Institute of Radiation Oncology | Lax I.,Karolinska University Hospital | Timmerman R.,University of Texas Southwestern Medical Center | And 3 more authors.
International Journal of Radiation Oncology Biology Physics | Year: 2011

To evaluate the current status of stereotactic body radiotherapy (SBRT) and identify both advantages and disadvantages of its use in developing countries, a meeting composed of consultants of the International Atomic Energy Agency was held in Vienna in November 2006. Owing to continuous developments in the field, the meeting was extended by subsequent discussions and correspondence (2007-2010), which led to the summary presented here. The advantages and disadvantages of SBRT expected to be encountered in developing countries were identified. The definitions, typical treatment courses, and clinical results were presented. Thereafter, minimal methodology/technology requirements for SBRT were evaluated. Finally, characteristics of SBRT for developing countries were recommended. Patients for SBRT should be carefully selected, because single high-dose radiotherapy may cause serious complications in some serial organs at risk. Clinical experiences have been reported in some populations of lung cancer, lung oligometastases, liver cancer, pancreas cancer, and kidney cancer. Despite the disadvantages expected to be experienced in developing countries, SBRT using fewer fractions may be useful in selected patients with various extracranial cancers with favorable outcome and low toxicity. Copyright © 2011 Elsevier Inc.

Amit M.,Head and Neck Cancer Center | Amit M.,Clinical Research Institute at Rambam | Na'Ara S.,Head and Neck Cancer Center | Na'Ara S.,Clinical Research Institute at Rambam | And 8 more authors.
Head and Neck | Year: 2016

Background A positive margin is among the most significant factors that affects the outcome in head and neck squamous cell carcinoma (SCC). The purpose of this study was to compare the negative margin rates between 2 methods of intraoperative margin assessment in patients with oral cavity SCC. Methods A prospective, randomized controlled trial comparing 2 methods of intraoperative margin assessment: specimen-driven margins and patient-driven margins. Results The final analysis included 71 patients, 20 (29%) in the patient-driven margin arm. Frozen section analysis revealed positive/close surgical margins that led to an extension of the surgical resection in 22 of 51 patients (43%) in the specimen-driven margin arm, and 2 of 20 patients (10%) in the patient-driven margin arm (p =.01). After final pathological analysis, the wide negative margin rate was 84% in the specimen-driven margin arm, compared to 55% in the patient-driven margin arm (p =.02). Extension of the surgical resection prevented escalation of adjuvant treatment in 19 patients (38%) in the specimen-driven margin arm and 10% in the patient-driven margin arm. Conclusion Specimen derived margin assessment led to significant improvement in the rate of negative margins. © 2015 Wiley Periodicals, Inc..

Zimmermann F.,University of Basel | Wulf J.,Institute of Radiation Oncology | Lax I.,Karolinska University Hospital | Nagata Y.,Hiroshima University | And 3 more authors.
Frontiers of Radiation Therapy and Oncology | Year: 2010

For patients with early stage non-small cell lung cancer (NSCLC) unsuitable for resection local high-dose radiotherapy is the treatment of choice. In modern series even with escalated conformal radiotherapy local control rates of about 55% remain disappointing. Within the last years, stereotactic radiotherapy has been shown an effective treatment approach for early stage malignant lung tumors, combining the accurate focal dose delivery by stereotactic techniques with the biological advantages of dose escalated hypofractionated radiotherapy. Typical treatment regimens include three to five fractions over 1-2 weeks or 1 single fraction as radiosurgery. With adequate staging procedures including FDG-PET-CT scan and a low probability of subclinical involvement of unsuspicious locoregional lymph nodes, the concept is to irradiate the primary T1/2 tumor alone. Recent data report local control rates of up to 90%, with favorable results especially for patients in good general condition. Less than 10% of all patients develop isolated tumor recurrences in regional lymph nodes. Three-year survival is significantly improved to more than 80% when biological effective doses of more than 100 Gy are applied to patients in good conditions. Systemic tumor recurrence still is a major problem, making an additional systemic chemotherapy interesting for selected patients after hSRT, such as those younger than 75 years. © 2010 S. Karger AG.

Jena A.,PET Suite | Taneja S.,PET Suite | Gambhir A.,PET Suite | Mishra A.K.,Institute of Nuclear Medicine and Allied Sciences | And 6 more authors.
Clinical Nuclear Medicine | Year: 2016

Purpose: This study aimed to investigate the potential of hybrid gadolinium (Gd)-enhanced 18F-fluoroethyl-L-tyrosine (18F-FET) PET/MRI in distinguishing recurrence from radiation necrosis using simultaneously acquired multiple structural and functional parameters. Methods: Twenty-six patients (5 female and 21 male patients; mean ± SD age, 51.58 ± 15.97 years) with single or multiple contrast-enhancing brain lesions (n = 32) on MRI after surgery and radiation therapy were evaluated with simultaneously acquired Gd-enhanced 18F-FET PET/MRI. They were then followed up with resurgery and histopathological diagnosis (n = 9) and/ or clinical/MRI- or PET/MRI-based imaging follow-up (n = 17). PET/MR images were analyzed using manually drawn regions of interest over areas of maximal contrast enhancement and/or FET uptake. Maximum target-tobackground ratio (TBRmax), mean target-to-background ratio (TBRmean), and choline-to-creatine (Cho/Cr) ratios as well as normalized mean relative cerebral blood volume (rCBVmean) and mean apparent diffusion coefficient (ADCmean) were determined. The accuracy of each parameter individually and in various possible combinations for differentiating recurrence versus radiation necrosis was evaluated using 2-tailed independent samples Student t test, multivariate analysis of variance, and multivariate receiver operating characteristic analysis. Positive histopathological finding and long-term imaging/clinical follow-up suggestive of disease progression served as criterion standard. Results: Of 26 patients, 19 were classified as recurrence, with 7 patients showing radiation necrosis. Individually,TABmax, TBRmean, ADCmean, and Cho/Cr ratios as well as normalized rCBVmean was significant in differentiating recurrence from radiation necrosis, with an accuracy of 93.8% forTABmax, 87.5% for TBRmean, 81.3%forADCmean, 96.9% for Cho/Cr ratio, and 90.6% for normalized rCBVmean. The accuracy of both normalized rCBVmean and ADCmean was improved in combination withTABmax or Cho/Cr ratio. However,TABmax (or TBRmean) with Cho/Cr ratio yielded the highest accuracy, approaching up to 97%. Furthermore, maximum area under the curve is achieved with the combination of TBRmean, CBV, and Cho/Cr values. Conclusions: Our findings suggest that FET uptake with Cho/Cr ratio and normalized rCBVmean could be most useful to distinguish primary glioma recurrence from radiation necrosis. Hybrid simultaneous multiparametric 18F-FET PET/MRI might play a significant role in the evaluation of patients with suspected glioma recurrence. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved.

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