Chemoradiation and consolidation chemotherapy for rectal cancer provides a high rate of organ preservation with a very good long-term oncological outcome: a single-center cohort series

Abstract

Aim To report long-term oncological outcomes and organ preservation rate with a chemoradiotherapy-consolidation chemotherapy (CRT-CNCT) treatment for locally advanced rectal cancer (LARC). Method Retrospective analysis of prospectively maintained database was performed. Oncological outcomes of mid-low LARC patients (n=60) were analyzed after a follow-up of 63 (50-83) months. Patients with clinical complete response (cCR) were treated with the watch-and-wait (WW) protocol. Patients who could not achieve cCR were treated with total mesorectal excision (TME) or local excision (LE). Results Thirty-nine (65\%) patients who achieved cCR were treated with the WW protocol. TME was performed in 15 (25\%) patients and LE was performed in 6 (10\%) patients. During the follow-up period, 10 (25.6\%) patients in the WW group had regrowth (RG) and 3 (7.7\%) had distant metastasis (DM). Five-year overall survival (OS) and disease-free survival (DFS) were 90.1\% and 71.6\%, respectively, in the WW group. Five-year OS and DFS were 94.9\% (95\% CI: 88-100\%) and 80\% (95\% CI: 55.2-100\%), respectively, in the RG group. For all patients (n=60), 5-year TME-free DFS was 57.3\% (95\% CI: 44.3-70.2\%) and organ preservation-adapted DFS was 77.5\% (95\% CI: 66.4-88.4\%). For the WW group (n=39), 5-year TME-free DFS was 77.5\% (95\% CI: 63.2-91.8\%) and organ preservation-adapted DFS was 85.0\% (95\% CI: 72.3-97.8\%). Conclusion CRT-CNCT provides cCR as high as 2/3 of LARC patients. Regrowths, developed during follow-up, can be successfully salvaged without causing oncological disadvantage if strict surveillance is performed.