Local excision in rectal cancer patients with major or complete clinical response after neoadjuvant therapy: a case-matched study

Purpose To assess the long-term oncological outcomes in patients with locally advanced rectal cancer who underwent neoadjuvant therapy followed by local or total mesorectal excision. Methods Patients with locally advanced rectal adenocarcinoma who received neoadjuvant therapy from 2005 to 2017 were evaluated. Those with major or complete clinical response underwent a full-thickness local excision. Kaplan-Meier estimates were used to evaluate overall, disease-free, and local recurrence-free survival of patients who underwent local excision (LE group) and were compared with a matched cohort of patients who underwent total mesorectal excision (TME group). Results Among 252 patients who received neoadjuvant therapy for rectal cancer, 51 (20.2%) underwent a local excision. At a median follow-up of 61 months, patients who underwent local excision were stoma-free in 88.2% of cases and with rectum preserved in 78.5% of cases, respectively. The estimated 5-year local, disease-free, and overall survival was 91.8% vs 97.6% (95% CI: 79.5-96.8 vs 84.6-99.6), 86.7% vs 86.4% (95% CI: 72.5-93.9 vs 70.1-94.1), and 85% vs 90% (95% CI: 69.0-93.0% vs 75.3-96.2), in the study and matched control group, respectively. None of the differences was statistically significant. Conclusions One-fifth of patients with locally advanced rectal cancer are manageable with a rectum-sparing approach after neoadjuvant therapy. With this strategy, about 80% patients will have their rectum preserved and 90% will be without stoma at long term.