Total neoadjuvant chemoradiotherapy (consolidation chemotherapy during the interval after chemoradiotherapy) for distal rectal cancer increases the rates of complete response
Abstract Objective To compare the safety and efficacy between neoadjuvant concurrent chemoradiotherapy (CRT) and total neoadjuvant chemoradiotherapy (TNT) in patients with locally advanced rectal cancer. Methods Patients with cT3/T4 or TxN+M0 rectal cancer were randomized to receive CRT/TNT. In CRT group, we planned pelvic radiotherapy (50.0Gy in 25 fractions) with two cycles of concurrent CAPOX followed by total mesorectal excision (TME). In TNT group, 3 cycles of CAPOX were administered 2 weeks after the completion of CRT before TME. The primary endpoints of my study were pathological complete response (pCR) rates in the two cohorts. Results A total of 197 patients were included in our study. Eighty-one patients received CRT while one hundred and sixteen patients received TNT (consolidation chemotherapy). Nine patients did not undergo surgery because of the distant metastases (1 patient (1.2%) in CRT group, 2 patients (1.7%) in TNT group) or clinical complete response (cCR) (2 patients in CRT group, 4 patients in TNT group). The rate of pathological complete response in TNT was significantly higher than the rate in CRT (32.7% vs12.8%, P =0.002). No grade 4 or serious adverse events were observed. There was no statistically significant difference in the grade 3 acute toxicities of neoadjuvant treatment and surgical complications between the two groups (all P >0.05). Conclusions Our data suggests that total neoadjuvant chemoradiotherapy (consolidation chemotherapy) is effective and safe for patients with locally advanced rectal cancer and is associated with high rates of pathological complete response. The long-term follow-up and survival outcomes for patients are necessary to be evaluated in future prospective randomized trial.