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Background: Evaluation of a HDR- interstitial brachytherapy plan is a challenging job. Owing to the complexities and diversity of the normalization and optimization techniques involved, a simple objective assessment of these plans is required. This can improve the radiation dose coverage of the tumour with decreased organ toxicity.Aim: To study and document the various dose volume indices and parameters required to evaluate a HDR interstitial brachytherapy plan by Volume normalization and graphical optimization using MUPIT (Martinez Universal Perineal Interstitial Template) in patients of carcinoma cervix.Settings and Design: Single arm, retrospective study.Methods and Materials: 35 patients of carcinoma cervix who received EBRT and HDR brachytherapy using MUPIT, were selected. The dose prescribed was 4 Gray/Fraction in four fractions (16Gy/4) treated twice daily, at least 6 hours apart. CTV and OARs were delineated on the axial CT image set. Volume normalization and graphical optimization was done for planning. Coverage Index (CI), Dose homogeneity index (DHI), Overdose index (OI), Dose non-uniformity ratio (DNR), Conformity Index (COIN) and dose volume parameters i.e. D2cc, D1cc, D0.1cc of rectum and bladder were evaluated.Statistical Analysis: SPSS version 16 was used.Results and Conclusion: CI was 0.95 ± 1.84 which means 95% of the target received 100% of the prescribed dose. The mean COIN was 0.841 ± 0.06 and DHI was 0.502 ± 0.11. D2cc rectum and bladder was 3.40 ± 0.56 and 2.95 ± 0.62 respectively which was within the tolerance limit of this organs. There should be an optimum balance between these indices for improving the quality of the implant and to yield maximum clinical benefit out of it, keeping the dose to the OARs in limit. Dose optimization should be carefully monitered and an institutional protocol should be devised for the acceptability criteria of these plans. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to establish a dosimetric correlation between the bladder volume and its effects on the dose received by the organs at risk (OARs) (urinary bladder, rectum, and sigmoid) during computed tomography (CT)-guided high-dose-rate (HDR) brachytherapy in carcinoma cervix, and to determine an optimum bladder volume to limit the dose to OARs. Material and methods: Seventy-five intracavitary applications in patients of carcinoma cervix (stage IIB, IIIA, IIIB, IVA) treated with external beam radiotherapy with concurrent chemotherapy followed by CT-based HDR intracavitary brachytherapy (tandem and ovoid type) at our institute between July 2014 to January 2016 were studied. The bladder volume at the time of imaging was noted and was correlated with the radiation dose received by bladder, rectum, and sigmoid colon. Results: Dose volume histogram (DVH) parameters of the bladder increases by elevating the volume of the bladder. Rectum dose does not follow a continuous increasing trend. It increases up to a bladder volume of 110 cc and then starts decreasing. The highest rectal dose observed was in the bladder volume, range 70-110 cc. The minimum doses were recorded when the bladder volume was > 170 cc. Sigmoid colon DVH parameters follow a similar trend as that of the rectum. Conclusions: A relationship exists between the volume of the OARs and the dose received by them. A bladder volume of about 70 cm³ or less proved better for achieving the prescribed dose limits of bladder, rectum, and sigmoid. The correlations between the bladder volume and the doses received by the OARs were not significant. [ABSTRACT FROM AUTHOR]

More than 1/3rd of head and neck cancer patients eventually fail loco-regionally or appear as second primary, despite ever-improving treatment options.1,2 Recommended potentially curative treatment options include salvage surgery if the disease is amenable to surgery, or reirradiation.2 Reirradiation of head and neck cancers presents a dilemma in terms of achieving adequate doses to the target, maintaining the organ-at-risks (OAR) dose constraints within limits, and managing toxicities emerging during and after the treatment.3–5 Intensity-modulated radiotherapy (IMRT) has slowly evolved to be the modality of choice for re-irradiation owing to its ability to improve disease control and reduce treatment-related toxicity.6 We present the data of re-irradiated head and neck cancer patients treated at our centre with IMRT. This was a retrospective single-arm observational analysis. Details of head and neck cancer patients treated at our hospital with re-irradiation were retrieved. After reviewing all the treatment records, the follow-up details were assembled. All the cases were treated with IMRT with or without concurrent chemotherapy. All the patients received radiation and re-irradiation with a dose-per-fraction of 1.8 to 2Gray with adjuvant or definitive intent, for five days a week for six weeks or above. The dose prescribed was preferably 60 – 66Gy in 30-33 fractions. Dose constraints used for OARs were: Spinal cord Dmax <=45Gy, and brainstem and optic apparatus Dmax <=54Gy.3,5 Special care was also taken to limit the cumulative dose of carotid arteries to <120Gy.7 The mean dose of parotid was limited at 23Gy, although target volume coverage was given priority, whenever the two were in proximity. Patients were immobilised using a 5-clamp head and neck thermoplastic mask. 3 mm slice thickness contrast-enhanced computed tomography (CT) images were obtained from vertex to 2 cm below the carina using Siemens Emotion 6 (Somatom, Germany). The treatment planning was done on MONACO (Version 5.11). The target volumes for definitive treatment were contoured as per ICRU 62.8 The decision to include nodes depended on certain factors: previous history of nodal positivity, nature of irradiation in the first radiotherapy schedule, nature and location of primary during second irradiation, definitive/adjuvant intent of re-irradiation, surgical resection of nodes, duration between the irradiation treatments, dose volumes used and dosimetric parameters achieved for OARs in the first radiotherapy. Patients were treated by using linear accelerator (Elekta Compact and Synergy; Elekta, Crawley, UK). All patients were followed up on a regular basis. Response assessment scans were done after 3 months of treatment completion. Overall Survival (OS) was defined time from start date of re-irradiation to the date of death or date of last clinical follow-up. Progression-free survival (PFS) was defined as interval from the start date of RT to any documented recurrence. Analysis was performed with the SPSS statistical (version 23.0; IBM, Armonk, NY, USA). All potential prognostic factors were analysed. the patients were divided into three prognostic subgroups using Multi-Institution Re-irradiation (MIRI) recursive partitioning analysis (RPA).9 Seventy-three cases were included in the final analysis. During the re-irradiation schedule, 34/73 cases were treated with definitive irradiation, whereas 39 cases were treated with postoperative adjuvant radiotherapy. Median interval between both the RT schedules was 55 months (range: 13-197). Median follow-up duration after re-irradiation was 23 months (range: 4-74). Median initial RT dose was 60 Gy (range: 58-66) and median re-irradiation dose was 60Gy (range: 54-66). The median initial RT and re-irradiation dose was 2Gy (range: 1.8-2). There were 41 events in PFS. The 2-year and 4-year PFS rates were 55.8% and 29.2%. The estimated 4-year DFS definitive re-irradiation versus adjuvant radiotherapy were 28.7 vs 29.3% (p-0.786). There was no statistically significant difference for 3-year OS of de novo versus post-operative cases (54.7 vs 56.3%, p-0.559). No significant differences in DFS or OS were elucidated for duration of re-irradiation for a 2-year period (48.6 vs 39.7, p-0.648) and 3-year period (3yr DFS – 48 vs 57.5%, p-0.091). Patients recurring within 2 years of primary radiation had poorer OS than those recurring after 2 years. (57.14 vs 49.25%, p-0.039). Patients with more than 3 high-risk factors during adjuvant reirradiation post-surgery had poor OS. (38.46 vs 31.5%, p-0.043). The number of cases in RPA Class I, II, and III were 16, 49 and 8, respectively. The 2-year DFS for Class I, II and III, were 62.5%, 59.7% and 12.5% (p<0.0001). Re-irradiation in head and neck cancers is tolerable and toxicities are acceptable. A larger cohort and a longer duration of study will help in discerning the factors that will help in reducing the toxicities and improving outcomes further. [ABSTRACT FROM AUTHOR]

Endometrial cancer is the 4th most common cancer in females in India as per 2020 report from National Cancer Registry Programme (NCRP). Incidence of endometrial cancer in India is 105.5 per 100,000 women with highest being observed in Bangalore and Delhi. Management of endometrial cancer remains a challenge due to an older age population with considerable comorbidity. Surgery with or without adjuvant therapy is the standard of care in endometrial cancer, whereas upfront combination of external beam radiotherapy (EBRT) and HDR (High Dose Rate) brachytherapy (BT) or BT alone is indicated for inoperable or unresectable cases. Twenty two patients with inoperable or unresectable endometrial cancer were treated with upfront radiotherapy from 2015 to 2021. Eighteen patients received EBRT followed by HDR BT as Intracavitary radiotherapy (ICR) with Central Vaginal Cylinder (CVC), while four patients received HDR BT as monotherapy. Definitive radiotherapy was given in the form of EBRT 50 Gy in 25 fractions, 5 fractions/week followed by HDR BT as CT based ICR plus CVC, 7.5Gy per fraction, 2 fractions, 1 week apart. Outcomes were analysed retrospectively in terms of Cancer Specific Survival (CSS), Overall survival(OS) and Local control (LC). Kaplan Meire estimates of OS and PFS were determined using SPSS IBM Software version 26.0. Median age of presentation was 56.5 years (IQR: 45-74 years) and median Body mass index (BMI) was 28.48 (range 20.56-49.12). For the entire cohort, median follow up was 15.5 months (range 6-74). The mean CSS was 45.11 months (range- 28-62.19). The overall mean survival time of the study population was 46.34 months (range 27.71-64.98), with a survival rate of 75% at 2 years. The mean progression free survival was 49.22 months (range-32.26-66.19) and 2 years local control rate was 100%. No acute grade 3 and late grade 3 genitourinary or gastrointestinal toxicities were noted. Upfront radiotherapy is tolerated well among inoperable endometrial cancer patients, also including high risk patients with favorable local control and improved overall survival. [ABSTRACT FROM AUTHOR]