Oncologic Safety of Local Excision Compared with Total Mesorectal Excision for ypT0-T1 Rectal Cancer

Abstract

Good oncologic outcomes, demonstrated by a complete pathologic response after preoperative chemoradiotherapy (PCRT), have led to local excision (LE) in selected patients with rectal cancer. We evaluated the oncologic safety of LE compared with total mesorectal excision (TME) in patients with ypT0-T1 rectal cancer. A retrospective review of 304 patients who underwent PCRT, followed by LE or TME, for ypT0-T1 rectal cancer was performed. Propensity scores were computed and used to match groups (LE:TME=1:1), and analysis of disease-free survival (DFS) and overall survival (OS) was made by comparing patients who underwent LE or TME. Prognostic factors of relapse were analyzed for all patients. Tumor categories were ypT0 in 25 (61.9%) cases, ypTis in 6 (14.3%) cases, and ypT1 in 11 (26.2%) cases for the LE group, and ypT0 in 28 (66.7%) cases, ypTis in 4 (9.5%) cases, and ypT1 in 10 (23.8%) cases for the matched TME patients. There was no significant difference between the matched LE and TME groups in relapse (4.8% and 7.14%, respectively; P=0.646), 5-year DFS (95.2% vs 91.6%; P=0.33) and 5-year OS (96.6% vs 88.0%; P=0.238). In the multivariate Cox regression analysis, tumor distance from the anal verge (hazard ratio [HR]=0.78; 95% confidence interval (CI)=0.616-0.992) and the tumor grade (HR=4.29; 95% CI=1.430-12.886) were significantly associated with the recurrence risk. LE results in oncologic outcomes that are comparable to those achieved by TME in selected patients with ypT0-T1 rectal cancer after PCRT.