Neoadjuvant chemoradiation followed by transanal local excision for T2 rectal cancer confers equivalent survival benefit as traditional transabdominal resection

Background: Despite clinical guidelines classifying T2 rectal cancer as a contraindication for transanal local excision attributable to unacceptably high rates of local recurrence, it is a practice that persists clinically. Recent clinical trials have suggested that transanal local excision in addition to neoadjuvant chemoradiation is an acceptable alternative in select patients. Methods: The 2004–2015 National Cancer Database was queried for patients with clinical stage T2N0M0 rectal adenocarcinoma who underwent surgical intervention. Patients were stratified by treatment with transabdominal resection or transanal local excision, both with and without neoadjuvant chemoradiation. Propensity matching was performed, and, using the Kaplan-Meier and Cox proportional hazard models, survival was compared between the groups. Results: A total of 12,021 patients met inclusion criteria, including 1,761 and 6,629 patients who underwent transabdominal resection with and without neoadjuvant chemoradiation, respectively, and 695 and 2,936 patients who underwent local transanal excision with and without neoadjuvant chemoradiation, respectively. In unadjusted analysis, patients undergoing induction therapy followed by transabdominal resection or local excision had equivalent survival. Similarly, on multivariate Cox proportional hazard regression after propensity matching, local excision was not an independent predictor of patient mortality compared with transabdominal resection (hazard ratio 0.93, 95% confidence interval 0.75–1.16). Conclusion: Local transanal excision in addition to neoadjuvant chemoradiation may provide comparable survival benefit to transabdominal resection for patients with clinical stage T2N0M0 rectal cancer. Therefore, patients who refuse or are poor candidates for transabdominal resection should be considered for neoadjuvant therapy followed by transanal local excision.