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While multisession dose fractionated Gamma Knife radiosurgery (DFGKS) is common, its use has never been described for jugular paragangliomas (JP), which are notoriously difficult to treat. To define efficacy, safety, and complication profile of DFGKS in 2 or 3 consecutive sessions for the treatment of a cohort of 10 cases of JP. Between 2012 and 2017, 10 patients with JP were treated with DFGKS in 2 or 3 sessions, because it was not safe to treat the lesion in a single session because of the large volume or proximity to organs at risk. The small to medium-sized JP are treated with 16–22 Gy radiation, but the large-volume JP were treated with 23–25 Gy radiation dose. The Leksell G frame was kept in situ during the whole procedure. The tumor volumes on pretreatment and posttreatment imaging were compared, using the Leksell Gamma Plan treatment plan software to assess tumor progression. The patients were regularly evaluated for their clinical outcome with radiologic correlation. The mean radiologic follow-up was 39 months (range, 12–78 months). The mean marginal dose for 3 fractions and 2 fractions was 7.64 Gy at 50% and 11.2 Gy at 50%, respectively. The mean tumor size was 29.9 cm3 (range, 9.95–47.63 cm3) at treatment and 21.9 cm3 (range, 8.83–37.5 cm3) at follow-up (suggestive of 26.7% reduction). Tumor control was achieved in all patients (100%). Of 110 potential neurologic problems (signs/symptoms) evaluated (11 in each patient), 56 (50.9%) were present preoperatively. Of them, 27 (48.2%) improved and 29 (51.8%) stabilized after treatment. There were 2 new-onset neurologic problems (of 110, 1.8%) attributable to treatment (new-onset headache and spinal accessory paresis). No patient had any permanent neurologic deterioration. DFGKS for large-volume JP leads to acceptable progression-free survival, tumor control rate, and symptomatic improvement. It may be preferred to surgery or fractionated radiotherapy given its better safety, efficacy, and complication profile. [ABSTRACT FROM AUTHOR]

Nanocrystals of the Li2B4O7:Cu were synthesized by a combustion method using 1000ppm and 2500ppm concentrations of Cu. TL characteristics of the synthesized Li2B4O7:Cu material doped with Cu of concentration 1000ppm and 2500ppm were studied using 150MeV proton beam, 4MeV and 9MeV electron beam. It is observed that Li2B4O7:Cu doped with Cu (both 1000ppm and 2500ppm) exhibits a linear response in the range 1×100–3×101 Gy for exposure to 150MeV proton beam. Nanocrystalline Li2B4O7:Cu, doped with 1000ppm and 2500ppm Cu, shows a linear TL response in the range 1×10−1–1×101 Gy for 4MeV and 9MeV electron beam. Fading of phosphors was also studied and it was found that Li2B4O7:Cu is quite suitable for proton and electron beam dosimetry. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To evaluate dosimetric and clinical outcome in patients of anal cancer treated with image-based interstitial high-dose-rate brachytherapy following chemoradiation. Methods and Materials: Sixteen patients with anal cancer were treated with chemoradiation followed by brachytherapy boost with image-based high-dose-rate interstitial brachytherapy from January 2007 to June 2011. Two brachytherapy dose schedules were used: 21 Gy in seven fractions and 18 Gy in six fractions depending on response to chemoradiation. CT scan was done after placement of needles for confirmation of placement and treatment planning. Target volume was contoured on CT scans. Volumetric quality indices and dose parameters were calculated. Results: The mean clinical target volume was 17.7 ± 4.98 cm3, and the median overall tumor size was 4.2cm (3.4–5cm). The mean values of coverage index, dose homogeneity index, overdose volume index, dose non-uniformity ratio, and conformal index were 0.94, 0.83, 0.21, 0.37, and 0.88, respectively. With a median followup of 41 months (range, 20–67.2 months), preservation of the anal sphincter was achieved in 14 patients. The 1- and 2-year local control rates were 93.8% and 87.5%, respectively. Treatment was well tolerated and none of the patients developed Grade 3 or higher late toxicity. Conclusions: The combination of external beam radiotherapy with interstitial brachytherapy increases the dose to the tumor volume and limits the volume of irradiated normal tissue, thereby decreasing late toxicity. The use of image-based treatment planning provides better dose conformality with reduced toxicity and helps to prevent a geographic miss. [Copyright &y& Elsevier]

Abstract: Purpose: To test the toxicity and efficacy of concomitant boost radiotherapy alone against concurrent chemoradiation (conventional fractionation) in locally advanced oropharyngeal cancer in our patient population. Methods and materials: In this open-label, randomised trial, 216 patients with histologically proven Stage III–IVA oropharyngeal cancer were randomly assigned between June 2006 and December 2010 to receive either chemoradiation (CRT) to a dose of 66Gy in 33 fractions over 6.5weeks with concurrent cisplatin (100mg/m2 on days 1, 22 and 43) or accelerated radiotherapy with concomitant boost (CBRT) to a dose of 67.5Gy in 40 fractions over 5weeks. The compliance, toxicity and quality of life were investigated. Disease-free survival (DFS) and overall survival (OS) curves were estimated with the Kaplan–Meier method and compared using log rank test. Results: The compliance to radiotherapy was superior in concomitant boost with lesser treatment interruptions (p =0.004). Expected acute toxicities were significantly higher in CRT, except for grade 3/4 mucositis which was seen more in CBRT arm (39% and 55% in CRT and CBRT, respectively; p =0.02). Late toxicities like Grade 3 xerostomia were significantly high in CRT arm than CBRT arm (33% versus 18%; p <0.0001). The quality of life was significantly poor in CRT arm at all follow up visits (p <0.0001). The rates of 2year disease-free survival were similar with 56% in the chemoradiotherapy group and 61% in CBRT group (p =0.2; HR-0.81, 95%CI-0.53–1.2). Subgroup analysis revealed that patients with nodal size >2cm had significantly better DFS with CRT (p =0.05; HR-1.59, 95%CI-0.93–2.7). Conclusion: In selected patients of locally advanced oropharyngeal cancer, concomitant boost offers a better compliance, toxicity profile and quality of life with similar disease control, than chemoradiation. [Copyright &y& Elsevier]