Long-Term Outcomes of Neoadjuvant Chemoradiotherapy with Total Mesorectal Excision in Locally Advanced Rectal Cancer: An Institutional Analysis.

Abstract Purpose: We aimed to determine the long-term oncologic outcome for patients with rectal cancer treated with preoperative Chemoradiotherapy (CRT) followed by total mesorectal excision (TME). In addition, we attempted to identify prognostic factors and the oncologic significance of a pathological complete response (pCR) on the patient's oncologic outcome. Materials and Methods: Between February 1993 and January 2019, a prospectively maintained database of 357 consecutive patients with locally advanced (cT3-4 or any N1-2) primary rectal adenocarcinoma who received preoperative CRT followed by curative TME at our institute was analyzed. Results: With a median follow-up of 72 (23–295) months, local recurrence occurred in 21 (5.9%) patients. The 5-, 10-, and 15-year locoregional free survival rates were 92.7%, 91.3%, and 91.3%, respectively. The median time to pelvic recurrence was 28 (12–103) months. Pathologic complete response was reported in 41 (11.6%) patients, and no patient with pCR developed local recurrence. Advanced pathologic T stage, pathologic nodal stage, and circumferential resection margin involvement were significantly poor prognostic factors for these patients. Conclusion: Neoadjuvant radiochemotherapy for rectal cancer significantly improved the down-staging and sphincter preservation rates of low-lying rectal carcinomas. However, some patients will continue to recur after 5 years of follow-up.