Our experience with transanal total mesorectal excision (TaTME) procedures in middle and distal rectal tumors.

Introduction: Transanal total mesorectal excision (TaTME) is a relatively new approach in surgical treatment of rectal cancer. There are no clear indications when to choose this strategy. It is a technically demanding procedure for the surgeon with a long learning curve, which should also be taken into account in evaluation of this method. The results of both oncological and postoperative complications must be properly evaluated to explore the benefit of TaTME. The aim of this study is to assess the potential benefit of TaTME compared to other alternatives in middle and distal rectal tumors.

Methods: Retrospective evaluation of patients undergoing TaTME procedure performed by one team of surgeons between October 2014 and June 2019. The authors analyzed demographic indicators of the group of patients, tumor characteristics, specimen quality, early postoperative complications and the possibility of stoma reversal.

Results: A total of 93 patients underwent TaTME procedure for middle and distal rectal cancer. Mean BMI was 27.6 (4.8). T3 or T4 tumor was found in 73 (78.5%) patients, 68 (73.1%) patients had positive lymph nodes and 12 (12.9%) patients were treated for synchronous metastatic rectal cancer. Neoadjuvant therapy was used in 80 (86%) patients. Conversion to open laparotomy was necessary in one case (1%). Stapled anastomosis was performed in 37 (39.7%) cases, handsewn in 56 (60.2%). A positive circumferential resection margin (CRM) was found in 10 (10.7%) cases. Distal resection margin (DRM) was positive in 3 (3.2%) patients. Pathological analysis showed a complete mesorectum in 18 patients (19.4%), nearly complete in 39 (41.9%) and an incomplete mesorectum in 36 (38.7%). Complications in the first 30 days after primary surgery were observed in 38 (40.8%) patients, mainly for anastomotic leak (19 patients, 20.4%). Reoperation was required in 7 (7.5%) patients. Permanent colostomy had to be performed in 4 (4.3%) cases. No patient died after surgery.

Conclusion: In a selected group of patients it is possible to perform resection using this approach with acceptable postoperative morbidity and quality of the specimen. We used TaTME procedure in patients expected to have difficult TME due to obesity, size and distal localization of tumor. The incidence of conversion to open surgery was very low. Further studies for long term oncological outcomes are needed.