Transanal total mesorectal excision: 3-year oncological outcomes.

BACKGROUND Rectal cancer treatment has evolved with the implementation of new surgical techniques. Transanal total mesorectal excision (TaTME) is the most recent approach developed to facilitate pelvic dissection of mid- and distal rectal tumours. The purpose of this study was to analyse the short- and mid-term oncological outcomes of TaTME. METHODS A study was conducted on patients treated with TaTME for rectal cancer at two colorectal units in Portugal between March 2016 and December 2018. Clinical, pathological and oncological data were retrospectively analysed. Primary endpoints were 3-year overall survival, disease-free survival and local recurrence. Secondary endpoints were clinical and pathological outcomes. RESULTS Fifty patients (31 males, [62%], median age 66 years [range 40-85 years]) underwent TaTME, 49 (98%) for malignant and 1 (2%) for benign disease. There were no cases of conversion, 49 (98%) patients had complete or near-complete mesorectum, all the resections were R0 with adequate distal and circumferential margins. With a median follow-up of 36 months, there were 2 cases (4%) of local recurrence and 3-year estimated overall survival and disease-free survival were 90% and 79%, respectively. CONCLUSIONS TaTME can provide safe mid-term oncological outcomes, similar to what has been published for classic and laparoscopic TME. Our results also show how demanding this novel approach can be and the consequent need for audited data and standardized implementation.