Image guided adaptive brachytherapy of cervical cancer - practical recommendations.

Abstract

Brachytherapy (BT) is an integral part of radical radiotherapy (RT) or radiochemotherapy (RCT) in patients who are not suitable candidates for surgery. These are usually patients with locally advanced cervical cancer. The goal of all BT planning eff orts has been, still is, and certainly will continue to be, to defi ne the anatomical boundaries of the tumor and the relationship of the tumor to organs at risk (OARs) as best as possible, using available modern imaging techniques. Image guided adaptive brachytherapy (IGABT) is currently the most advanced method of uterovaginal BT. Adaptive planning allows dose escalation from BT to newly defi ned target volumes, according to the risk of recurrence, which is mainly determined by the level of tumor burden. This dose adaptation based on the response to external RCT is a major change in practice compared to conventional BT planning based on dose prescription to point A. The main advantage of the IGABT concept is that it allows the assessment of individual dose distributions in target volumes and OARs, which in turn leads to improved dose coverage of target volumes while decreasing the volume irradiated by the prescribed dose compared to conventional 2D planning. Purpose: In this review article, I provide a comprehensive up-to-date perspective on this issue, particularly in terms of practical recommendations regarding the defi nition of target volumes, the use of diff erent types of uterovaginal applicators, intraoperative complications, and potential manifestations of late gastrointestinal, genitourinary, and vaginal toxicity.