Usefulness of transanal approach for lower rectal cancer: a propensity score-matched analysis

Aim: Transanal approaches, such as transanal total mesorectal excision and transperineal abdominoperineal resection, have been developed to improve surgical quality for lower rectal cancer. However, international concerns have been raised about higher local recurrence rates. We investigated the usefulness of the transanal approach with respect to short- and long-term outcomes. Methods: In total, 291 patients who underwent laparoscopic or robotic surgery for rectal cancer were enrolled. Clinical, pathological, surgical, and follow-up data were retrospectively collected. Patients were divided into a transanal approach group (n = 139) and a conventional total mesorectal excision group (n = 152). A 1:1 propensity score-matched analysis was performed to compare surgical outcomes between the two groups. Results: After matching, 65 patients were included in each group. In the transanal group, intersphincteric resection was performed more frequently and abdominoperineal resection was performed less frequently, resulting in a higher rate of anus preservation (72.3% vs. 53.8%). The operative time was shorter (278 [240–343] min vs. 317 [259–373] min, p = 0.030), and blood loss was lower (29 [10–50] mL vs. 50 [10–119] mL, p = 0.033) in the transanal group. Major complications (Clavien–Dindo ≥ III) were less frequent in the transanal group. Overall survival was also better in the transanal group. No significant difference was observed in the total recurrence rate, including local recurrence. Conclusions: The transanal approach may be a promising surgical option for lower rectal cancer, contributing to higher rates of anus preservation and improved short- and long-term outcomes.