A comparison of organs at risk doses in GYN intracavitary brachytherapy for different tandem lengths and bladder volumes.

A comparison of organs at risk doses in GYN intracavitary brachytherapy for different tandem lengths and bladder volumes. J Appl Clin Med Phys. 2016;17(3):5584 Authors: Siavashpour Z, Aghamiri MR, Jaberi R, ZareAkha N, Dehghan Manshadi HR, Kirisits C, Sedaghat M Abstract The purpose of this study was to investigate the concurrent effects of tandem length and bladder volume on dose to pelvic organs at risk (OARs) in HDR intracavitary brachytherapy treatment of cervical cancer. Twenty patients with locally advanced cervical cancer were selected for brachytherapy using Rotterdam applicators. The patients were CT scanned twice with empty and full bladder. Two treatment plans were prepared on each of the image sets. Patients were categorized into two groups; those treated with a tandem length of 4 cm or smaller (T ≤ 4 cm) and those with tandem length larger than 4 cm (T > 4 cm). Only one tandem tip angle of 30° was studied. Dose-volume histograms (DVHs) of OARs were calculated and compared. Bladder dose was significantly affected by both bladder volume and tandem physical length for T ≤ 4 cm. This was reflected on the values obtained for D2cm³, D1cm³, and D0.1cm³ for both empty and full bladder cases. When T > 4 cm, no correlation could be established between variations in bladder dose and blad-der volume. Rectum dose was generally lower when the bladder was empty and T > 4 cm. Dose to sigmoid was increased wh...
Source: Journal of Applied Clinical Medical Physics - Category: Physics Authors: Tags: J Appl Clin Med Phys Source Type: research