Partial Mesorectal Excision Can Be a Primary Option for Middle Rectal Cancer: A Propensity-score Matched Retrospective Analysis

Abstract

Abstract Backgrounds Although partial or total mesorectal excision (PME and TME) is primarily indicated for the upper and lower rectal cancer, respectively, few studies have evaluated whether partial or total mesorectal excision (PME or TME) is more optimal for middle rectal cancer. Methods This study included 671 patients with middle/upper rectal cancer who underwent robot-assisted PME or TME. The two groups were optimized by propensity-score matching of sex, age, clinical stage, tumor location, and neoadjuvant treatment. Results Complete mesorectal excision was achieved in 617 (92%) of 671 patients, without showing difference between the PME and TME groups. Local (5.3% vs 4.3%, p = 1) and systemic (8.5% vs 16%, p = 0.181) recurrence rates also did not differ between the two groups, respectively, in patients with middle/upper rectal cancer. A comparison of the PME and TME groups with middle rectal cancer showed no significant differences in 5-year DFS (81.4% vs 74%, p = 0.537) and OS (88% vs 81.1%, p = 0.847) rates. Moreover, 5-year recurrence and survival rates were not affected by distal resection margins of 2–4 cm (p = 0.112–1), regardless of pathological stages. Postoperative complication rate was higher in the TME than in the PME group (21.4% vs 14.5%, p = 0.027). Incontinence was independently associated with TME (odds ratio [OR] = 2.009; 95% confidence interval = 1.015–3.975; p = 0.045), along with older age (OR = 4.366) and prolonged operation time (OR = 2.196) (p < 0.001–0.5). Conclusions PME can be primarily recommended for patients with middle rectal cancer with lower margin > 5 cm from the anal verge.