Advantages of inflatable multichannel endorectal applicator in the neo-adjuvant treatment of patients with locally advanced rectal cancer with HDR brachytherapy

Abstract

High dose rate endorectal brachytherapy is mainly used as a palliative treatment modality. In this paper, we compare dosimetry distributions for a single channel catheter (Miami) applicator with distributions of the inflatable multichannel (Novi) endorectal applicator. The comparisons are made with respect to dose coverage to the CTV as well as to the bladder, rectal wall, prostate and bone marrow. Our results suggest that multichannel applicator provides better sparing of the bone marrow by 50%, clinically uninvolved parts of the rectal wall by 70%, and bladder and prostate (in the case of male patients) by 100% in terms of ratio of cumulative doses to a 50 % of critical organ volume for single and multi channel endorectal applicators. Our results justify the advantage of using a mutichannel endorectal brachytherapy applicator as a neo-adjuvant treatment of patients with locally advanced rectal cancer.