Follow-up observation of rectal cancer patients with clinical complete response receiving non-operative and standard operative management after neo-adjuvant chemoradiotherapy

Objective: To investigate the feasibility of non-operative management (NOM) by comparing the therapeutic effects between NOM and total mesorectal excision (TME) for rectal cancer patients with clinical complete response (cCR) after neo-adjuvant chemoradiotherapy. Methods: A total of 135 patients with stage I/III rectal cancer who obtained cCR after neo-adjuvant chemoradiotherapy in Sun Yat-sen University Cancer Center from 2006 to 2016 were recruited and assigned into the NOM (n = 43) and standard operative management (SOM) groups (n = 92). The local recurrence rate, accumulative local control (LC) rate after salvage therapy, disease-free survival (DFS), overall survival (OS) and sphincter preservation rate were statistically compared between two groups. Kaplan-Meier analysis and log-rank test were utilized to calculate the LC, OS and DFS. Chi-square test was performed to calculate the sphincter preservation rate. Results The mean follow-up duration was 39 months (range: 10-127 months). Of 135 patients, the local recurrence rate and distant metastasis rate were 3.7% and 11.1%, and the 3-year DFS and OS were 90.5% and 97.0%. In the NOM and SOM groups, the 3-year DFS were 87% and 93%, and the 5-year DFS were 73% and 87% (P = 0.089). The 3-year OS were 98% and 99%, and the 5-year OS were 98% and 97% (P = 0.578). In the NOM group, the local recurrence rate was 12% (n = 5), 80% of patients received salvage treatment and the accumulative LC rate was calculated as 98%. In the SOM group, the local recurrence rate was 0, which was significantly lower than that in the NOM group (P = 0.O10). In the NOM group, the sphincter preservation rate was 93%, significantly higher compared with 70% in the SOM group (P = 0.030). Conclusions: It is feasible for rectal cancer patients with cCR to receive NOM following neo-adjuvant chemoradiotherapy. Partial locally recurrent patients can be healed by timely salvage therapy, thereby averting TME and relevant complications and enhancing the quality of life of rectal cancer patients. (authors)