A Consensus Approach to the Incorporation of Total Neoadjuvant Therapy in a Treatment Algorithm for Stage I-III Resectable Rectal Cancer.

Advances in surgical techniques, radiographic imaging capabilities, radiotherapy, and chemotherapy have led to improved outcomes for patients with rectal adenocarcinoma. Treatment strategies have correspondingly evolved, as seen with total neoadjuvant therapy (TNT) and organ preservation approaches. TNT is a treatment strategy for primary, non-metastatic, resectable mismatch repair proficient rectal cancer where the intent is to administer all appropriate adjuvant therapy in the preoperative phase, including both systemic therapy and chemoradiotherapy/radiotherapy. In this setting, TNT is increasingly administered for the purposes of maximizing tumour response to facilitate resection, improving treatment compliance, thus increasing the likelihood of a complete response to allow for organ preservation and for the possibility of improving survival. While several recent randomized controlled trials have described the role of TNT in the contemporary treatment of rectal cancer, there is significant heterogeneity in sequencing of treatments, dosing, allowance for non-operative management, and the potential for over-treatment. Our objective here was to incorporate current evidence to develop a consensus-based institutional treatment algorithm to be used in the ambulatory and multidisciplinary team setting for the treatment of stage I-III rectal cancer.