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Purpose: We undertook a prospective planning study to describe the delineation of ileal conduit (IC) loop on radiotherapy planning computed tomography (RTP CT) scan as an organ at risk (OAR) and its sparing using volumetric modulated arc therapy (VMAT) during adjuvant irradiation of bladder malignancies. Materials and Methods: Fifteen patients with bladder malignancy needing adjuvant radiotherapy postoperatively and having normal renal function underwent delayed phase RTP CT from June 2020 to March 2021, with certain modifications (Foley's catheter through stoma, additional delayed scans). We identified the course of ureters, external stoma, IC, and uretero-ileal (right and left) anastomotic sites. VMAT plans were generated. Results: A step-by-step description is given. Genitourinary OARs include kidneys, ureters, uretero-ileal anastomoses, and IC. The contrast on delayed scan opacifies ureters and IC. IC can be seen three-dimensionally as a structure with two fixed ends (blind proximal end anterior to the right sacroiliac joint and the open distal end over the right anterior abdominal wall in parasagittal location) and a 15-20 cm hanging intraabdominal loop that lies adjacent to the right iliac vessels. For prescription doses (PD) of 50.4 gray and 54 gray, respectively, VMAT plan achieved IC dose maximum to less than PD and V50 lower than 10 cc. Stoma sparing traditionally used as a surrogate for IC sparing is insufficient due to the variable intraabdominal location of IC loop. Conclusions: Delineation of IC as an OAR is feasible with slight modifications in the RTP protocols. VMAT (or other forms of intensity modulated radiation therapy) can help IC sparing and should be considered when it lies in close proximity to target volumes and the risk of additional morbidity is considerable. [ABSTRACT FROM AUTHOR]

Nasal cavity as the first site of metastases from colorectal adenocarcinoma without metastases elsewhere is generally unheard of and very rare with only a few cases reported in world literature. The diagnostic dilemma and therapeutic challenge are significant when encountered in clinical practice, especially to differentiate it from a primary nasal pathology. Histopathological examination and immunohistochemistry play an important role. We report an unusual and interesting case of adenocarcinoma rectum with nasal metastases. A 65-year-old male was treated for adenocarcinoma rectum with radiotherapy, surgery and chemotherapy and was disease-free for 9 months post-treatment completion. Subsequently, he presented with nasal bleeding and on evaluation was found to have a nasal mass. Histopathological examination and immunohistochemistry confirmed the mass to be a metastasis from the earlier rectal adenocarcinoma. He received palliative haemostatic radiotherapy for bleeding from the nasal mass and was then treated with 6 cycles of 5-fluorouracil and irinotecan-based palliative chemotherapy. The patient achieved a good level of palliation, had near-complete regression of nasal mass on imaging with no new sites of metastases and hence was placed on regular follow up. [ABSTRACT FROM AUTHOR]

Context: Gliomas are a heterogeneous group of relatively rare cancers that have an important public health-care implication due to their high levels of mortality and morbidity. While standard management guidelines are available, their implementation in a resource-limited scenario needs greater scrutiny. Settings and Design: This is a retrospective analysis of disease characteristics, treatment parameters including the time to imaging and time to treatment, and overall survival (OS) at 1 and 5 years in patients of brain gliomas. Subjects and Methods: Demographic, clinical, and follow-up data of histologically proven glioma patients that received radiotherapy (RT) between 2009 and 2013 at two tertiary care hospitals of India were collected and analyzed. Statistical Analysis: Kaplan–Meier curves were used to compare OS at 12 and 60 months. Cross-tabulation and Pearson's Chi-square test were used to study the association of study variables with survival. Results: One hundred and nine patients were included. The mean age was 45 years and males were three times as common as females. Astrocytomas were the most common histology with Grade IV astrocytomas comprising 48% of the total. The OS at 12 and 60 months was 79.8% and 24%, respectively, for the entire cohort. The average time taken for brain imaging from onset of symptoms was 24 days, while the time to surgery and the time to start RT were 18 and 44 days, respectively. Old age and ability to tolerate treatment were shown to affect survival at 1 year from diagnosis, though tumor histology and grade had an apparent impact on long-term prognosis. Conclusions: Hospital registries are an important source of demographic and clinical information on less common cancers such as gliomas. Increasing awareness among the general public and sensitization of primary health-care apparatus are critical for early diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Aim: In the present study, surface doses within the target area and contralateral breast (CLB) received during conventional treatment of carcinoma breast are evaluate and compared for treatment on two different beam energies, i.e., Co-60 γ-ray and 6 MV X-ray beams with thermoluminescent dosimeter, LiF:Mg, Ti (TLD-100).Materials and Methods: The study includes a group of 23 patients comprising 11 patients treated with Co-60 γ-ray beam and 12 patients by 6 MV X-ray beam.Results and Discussion: The treatment using Co-60 γ-ray and 6 MV X-ray beams contributes an average percentage dose of 8.15% ± 0.56% and 4.73% ± 0.94%, respectively, to CLB in mastectomy patients. The contribution of tangential fields (mastectomy) to the CLB doses ranges between 12.71 and 16.40 cGy (5.45%-7.03%) for treatment with Co-60 γ-ray beam and 6.33-10.95 cGy (1.86-4.69%) for treatment with 6 MV X-ray beam. The supraclavicular field (SCF) contributes 1.45%-1.93% and 1.02%-1.43% for treatment with Co-60 γ-ray and 6 MV X-ray beams, respectively. The average surface dose (normalized with breast dose) 89.1% ± 8.5% for Co-60 beam in the SCF region differs significantly from the 60.2% ± 13.0% value for 6 MV X-ray beam.Conclusion: The CLB doses for mastectomy patients are higher for Co-60 beam as compared to 6 MV X-ray beam, and better dose homogeneity is achieved within the irradiated breast from 6 MV X-ray beam. The CLB doses are slightly higher for patients treated with breast conservative radiotherapy or lumpectomy. The average surface dose to SCF decreases by ~30% of treated breast dose for treatment with 6 MV X-ray beam. [ABSTRACT FROM AUTHOR]

Carcinoma of nasopharynx is a radiosensitive tumor and therapeutic response during radiation treatment can result in dosimetric variations in the delivered dose to the tumor and critical organs. This study was done to evaluate the volumetric and dosimetric changes seen in tumor tissue and organs at risk in a mid treatment planning scan and its implications for adaptive replanning. Twenty patients of locally advanced carcinoma nasopharynx were evaluated. All patients were started on treatment with a baseline treatment plan on SIB-VMAT. To evaluate volumetric and dosimetric changes during treatment, a mid treatment CT scan (MTS) was taken at the 17th fraction of treatment and compared with the baseline planning CT scan (BS). Adaptive treatment plans were generated on the MTS and further treatment was continued on the adaptive plans. The mean weight loss observed at the 17th fraction of treatment was 3.4 ± 2.6 kg(Mean±S.D). The mean neck diameter at C2 level was 14.19±1.02 and 13.29 ± 1.14 cm in the BS and MTS respectively (p=0.001). The GTV 70 volume showed a 29.16% volume loss. The mean doses received by the right and left parotids were 25.45±0.98 and 24.64±3.8 Gy in the baseline treatment plan and 33.21±11.29 (p=0.054) and 31.76±8.44 Gy respectively in the MTS (p=0.016) The mean weight loss showed a statistically significant correlation with increase in the right parotid(p=0.043) and left parotid doses(p=0.024). Weight loss during treatment combined with volume changes in target tissues mandate routine adaptive replanning while treating carcinoma nasopharynx. [ABSTRACT FROM AUTHOR]