FP1.8 - Optimizing Rectal Cancer Treatment: Comprehensive response to Neoadjuvant therapy

Abstract Aims This study aimed to assess the outcomes and feasibility of a watch-and-wait strategy in patients with rectal cancer showing a complete response to neoadjuvant chemoradiotherapy (CRT). The primary objectives included evaluating the oncological results, disease-free interval, and survival rates in patients who underwent the watch-and-wait approach after a complete clinical response. Methods The study involved a retrospective analysis of last 10 years of rectal cancer patients enrolled in a complete responder surveillance program in an acute general hospital. Cohort characteristics, including age, performance status, tumor histology, distance from the anal verge, and treatment modalities, were documented. Results The median age was 74 (57-90), and the median performance status was 1, with the age at diagnosis being 69. All cohort members had a histologically confirmed rectal adenocarcinoma. The median tumor-to-anal-verge distance was 5 cm (1-10 cm). Neoadjuvant chemotherapy was administered to 55% of patients. All patients underwent long-course radiotherapy, and 35% received papillon contact brachytherapy. Total neoadjuvant therapy was received by 10%. The median follow-up involved approximately 9 colonoscopies. During follow-up, 25% of patients experienced recurrence, with a median disease-free interval of 3.5 years. Conclusion The findings of this study, in addition to ongoing prospective clinical trials and insights from databases such as EURECCA and OnCore, indicate that a watch-and-wait approach can be safe and effective for selected rectal cancer patients who have achieved a complete response to neoadjuvant CRT. This study highlights the significance of additional research to identify appropriate patients for this approach and to refine its implementation in rectal cancer management.