Oncologic Outcome of ypT1-2N0 Rectal Cancer After Neoadjuvant Chemoradiotherapy Compared With pT1-2N0 Rectal Cancer

Objective: To investigate the oncologic outcome of ypT1-2N0 mid and lower rectal cancer after chemoradiotherapy (CRT) compared with pT1-2N0 rectal cancer. Methods: We compared the oncologic outcome of patients with mid and lower rectal cancer who underwent preoperative CRT and who did not, between February 2005 and August 2012. Results: Compared with patients who did not receive preoperative CRT, patients who received preoperative CRT did not have significantly different clinicopathologic features except clinical stage and distal resection margin. The 5-year disease-free survival (DFS) rates were lower in patients who received preoperative CRT than those who did not (84.4% vs. 95.5%, P = 0.029). Preoperative CRT was a prognostic factor affecting 5-year DFS in patients with pathologically proven stage T1N0 mid and lower rectal cancer (HR, 11.157; 95% CI, 1.735-71.762; P = 0.011) Conclusions: ypT2N0 rectal cancer after neoadjuvant CRT showed shorter DFS compared with pT2N0 rectal cancer.