Outcomes of transanal vs laparoscopic total mesorectal excision for mid and low rectal cancer under routine clinical practice conditions.

backgroundOncologic outcomes in mid and low rectal cancer depend critically on the quality and reproducibility of total mesorectal excision. Transanal total mesorectal excision (TaTME) has been introduced to address technical challenges in distal pelvic dissection and margin acquisition in selected patient populations. However, concerns regarding oncologic safety have been raised when TaTME is implemented outside controlled trial settings. Evidence from routine clinical practice is therefore needed to determine whether these outcomes are reproducible under real-world conditions. To compare 3-year (mid-term) oncologic outcomes between one-team TaTME and laparoscopic total mesorectal excision (LapTME) in patients with mid and low rectal cancer treated under routine clinical practice conditions.

methodsThis retrospective cohort study was conducted at a tertiary academic hospital. From January 2018 to May 2022, 256 consecutive patients with mid and low rectal adenocarcinoma undergoing curative-intent total mesorectal excision were included. Patients were categorized according to surgical approach (TaTME, n = 129; LapTME, n = 127). Propensity score matching was adjusted for baseline differences, yielding a matched cohort of 170 patients (TaTME, n = 108; LapTME, n = 62). The median follow-up duration was 48 months.

resultsAfter matching, baseline characteristics were well balanced between groups. Median operative time was longer and protective stoma formation was more frequent in the TaTME group, whereas intraoperative blood loss and rates of major postoperative complications were similar between groups. All specimens had negative distal and circumferential resection margins. The distribution of distal resection margin lengths was more tightly clustered in the TaTME group, indicating greater consistency in distal margin acquisition. At 3 years, local recurrence occurred in 3. 7%of patients in the TaTME group and 4. 8%in the LapTME group, and distant metastasis occurred in 13. 0 and 14. 5%, respectively. Three-year disease-free survival was 83. 3%in the TaTME group and 82. 3%in the LapTME group, and 3- year overall survival was 88. 9and 90. 3%, respectively.

conclusionsIn this single-center study conducted under routine clinical practice conditions, one-team TaTME was associated with 3-year oncologic outcomes comparable to those of LapTME for patients with mid and low rectal cancer. These findings suggest that, when performed by experienced surgical teams, one-team TaTME does not appear to compromise oncologic outcomes and may be appropriately considered within contemporary rectal cancer surgery under routine clinical conditions.