Local excision after preoperative chemoradiation results in an equivalent outcome to total mesorectal excision in selected patients with T3 rectal cancer

Background: We previously reported 26 patients who underwent preoperative chemoradiotherapy (CXRT) for T3 rectal cancer and were subsequently offered full-thickness local excision (LE) as an alternative to total mesorectal excision (TME). At nearly 4 years' follow-up, no difference in outcome was observed. This study compares outcomes in a larger cohort of patients and reevaluates the original 26 patients after longer follow-up. Methods: Retrospective review was performed of patients who underwent preoperative CXRT (radiation doses of 45, 50.4, or 52.5 Gy with concurrent 5-fluorouracil-based chemotherapy) followed by surgery for T3 rectal cancer. Forty-seven patients underwent LE (Kraske [n = 6] or transanal excision [n = 41]). 473 patients underwent TME (abdominoperineal resection [n = 141] or low anterior resection [n = 332]). Local recurrence, disease-free survival (DFS), disease-specific survival, and overall survival (OS) rates were compared. Results: Median follow-up was 63 months for the LE group and 59 months for the TME group. Twenty-three LE patients (49%) had a complete response to CXRT, 17 (36%) had microscopic residual disease, and 7 (15%) had gross residual disease, compared with 108 (23%), 89 (19%), and 276 (58%) TME patients, respectively. There was no significant difference between the 10-year actuarial local recurrence rate for the LE group versus the TME group (10.6% and 7.6%, respectively; P = .52), and no significant difference in DFS, disease-specific survival, or OS rates between groups. Conclusions: In selected patients who demonstrate an excellent response to preoperative CXRT for T3 rectal cancer, full-thickness LE offers comparable local control, DFS, and OS to that achieved with proctectomy and TME.