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Aims: To analyze the differences in dose distribution, with ovoid separation in various applications, by different radiotherapists in the same patient of carcinoma of the uterine cervix treated by multiple fractions of high-dose-rate (HDR) intracavitary Radio therapy (ICRT). Settings: Pravara Rural Hospital and Rural Medical College. Design: Retrospective study. Materials and Methods: Retrospective analysis of six cases of carcinoma uterine cervix, randomly chosen in the period from January 2004 and December 2007. Three selected radiotherapists performed the applicator placement for ICRT on the aforementioned patients in a consistent pattern-three consecutive ICRT treatments separated by weekly intervals. Ovoid separation was categorized into three groups: <25 mm, 26-35 mm and >36 mm. Prescribed point 'A' isodose lines with maximum separation laterally in right and left parametrium and antero-posteriorly in lateral plane was calculated for all 36 isodose charts for the 18 ICRT applications. Results: In this study, there proves to be a significant difference in the ovoid separation between the applications of the different radiotherapists in the same patient with multiple fractions of HDR-ICRT. The applications done by 'A' radiotherapist resulted in an ovoid separation of <25 mm more often, 'B' radiotherapist of >36 mm while, 'C' radiotherapist fell in between the two. Discussion and Conclusion: With more ovoid separation, lateral dose to parametrium was improved; however, antero-posterior dose was not significantly affected. In order to determine the best dose distribution, as evident in the dose charts of 'C' radiotherapist, it is recommended to choose the optimum ovoid separation in accordance to the patient's anatomy. [ABSTRACT FROM AUTHOR]

Aim: To report the difference in the bladder and rectum doses with different applications by the radiotherapists in the same patient of the carcinoma of the uterine cervix treated by multiple fractions of high-dose-rate (HDR) intracavitary brachytherapy (ICBT).Materials and Methods: Between January 2003 to December 2004, a total of 60 cases of the carcinoma uterine cervix were selected randomly for the retrospective analyses. All 60 cases were grouped in six groups according to the treating radiotherapist who did the HDR-ICBT application. Three radiotherapists were considered for this study, named A, B and C. Ten cases for each radiotherapist in whom all three applications were done by the same radiotherapist. And 10 cases for each radiotherapist with shared applications in the same patient (A+B, A+C and B+C). The bladder and rectal doses were calculated in reference to point "A" dose and were limited to 80% of prescribed point "A" dose, as per ICRU-38 recommendations. Received dose grouped in three groups--less then 80% (< 80%), 80-100% and above 100% (>100%). A total of 180 applications for 60 patients were calculated for the above analyses.Results: There is a lot of difference in the bladder and rectal doses with the application by the different radiotherapists, even in the same patient with multiple fractions of HDR-ICBT. Applications by 'A' radiotherapist were within the limits in the self as well as in the shared groups more number of times, by 'B' radiotherapist was more times exceeding the limit and by 'C' radiotherapist doses were in between the A and B.Discussion and Conclusion: For the rectal and bladder doses most important factors are patient's age, disease stage, duration between EBRT and HDR-ICRT and patient anatomy, but these differences can be minimized to some extent by careful application, proper packing and proper fixation. [ABSTRACT FROM AUTHOR]