CT-based adaptive high-dose-rate endorectal brachytherapy in the preoperative treatment of locally advanced rectal cancer: Technical and practical aspects.

PURPOSE

During the last decade due to the availability of a CT scan in the brachytherapy suite, high-dose-rate endorectal brachytherapy (HDREBT) has evolved as a CT-based daily adaptive treatment. An update of the technical and practical aspects of HDREBT is provided.

METHODS AND MATERIALS

Description of technical and practical aspects of HDREBT focused on the preoperative treatment of locally advanced rectal cancer. During preoperative HDREBT, 26 Gy is delivered in four daily applications of 6.5 Gy prescribed to the 100% isodose, covering the clinical target volume. Daily CT scans are obtained and used for plan optimization, leaving patient positioning unchanged between CT scan and treatment delivery.

RESULTS

All steps of HDREBT treatment procedure are discussed in detail: flexible proctosigmoidoscopy and clipping; patient setup; applicator placement; target delineation; treatment planning and delivery; and patient care. Afterward, treatment results are reviewed.

CONCLUSIONS

CT-based adaptive preoperative HDREBT is a practical and feasible therapy for locally advanced rectal cancer, offering excellent local control with a favorable toxicity profile.