Complete Pathological Response Following Radiochemotherapy for Locally Advanced Rectal Cancer: Short and Long-term Outcome.

Abstract

Preoperative radiochemotherapy (RCT) followed by total mesorectum excision has become the gold standard for locally advanced carcinoma of the low and middle rectum. The aim of the study is to evaluate the short and long-term outcomes of patients in complete pathological response (PR) following this treatment sequence. One hundred and thirty patients were retrospectively included between 2005 and 2017 in an expert centre, with 3 groups formed, according to the PR: i) complete PR (absence of tumour cells on the surgical specimen ypT0N0), ii) partial PR (T or N downsizing) and iii) without PR. The complete PR rate was 13.1%. The complete PR group tended to develop less symptomatic fistulas compared to partial PR and without PR groups (5.8% versus 13.5% versus 18.7, respectively; p=0.607). The 5-year disease-free survival was increased for complete-PR patients (93% versus 79% versus 47%, respectively; p=0.0003) without an improvement in overall survival. Complete PR is associated with an improvement in survival without recurrence and without an improvement in the overall survival at 5 years.