Endorectal Brachytherapy for Rectal Cancer

The management of rectal cancers has changed over the past decades towards a multidisciplinary strategy, combining radiotherapy, chemotherapy, and surgery. Local recurrence rates, dropped to less than 6 % with pre-operative radiotherapy and the standardization of total mesorectal excision (TME), at the price of increased peri-operative morbidity and functional sequelae. Since neoadjuvant treatment achieves up to 30 % complete response, organ preservation has been increasingly debated for good responders. With the introduction of better-quality imaging for tumour visualization and treatment planning, a new targeted radiation treatment was introduced with high dose rate endorectal brachytherapy (HDRBT), developped by Dr Te Vuong\'s team in Montreal. This treatment allows for radiotherapy dose escalation to increase the complete response rate, and subsequently the rate of patients amenable to rectal preservation. This phase 2 trial study is proposed to assess the feasibility of HDR brachytherapy after standard chemoradiotherapy among patients selected for rectal preservation.