Laparoscopic Total Mesorectal Excision Following Transanal Endoscopic Microsurgery for Rectal Cancer

Patients' selection for transanal endoscopic microsurgery (TEM) depends on diagnostic modalities; however, there are still some limitations in the preoperative diagnosis of rectal lesions, and in some reports, up to third of the adenomas resected by TEM were found to be adenocarcinoma; therefore, salvage radical resection (RR) remains necessary for achieving oncological resection. Salvage RR may encounter some technical problems as the violation of the mesorectum and the scar formation. In this study, we aimed to report the outcome in patients undergoing salvage RR in terms of morbidity and oncological results.

Demographic and clinical data pertaining to patients undergoing RR following TEM between 2004 and 2014 were retrospectively collected.

One hundred forty one TEM were performed in the study period, 53 (38%) for malignant rectal lesions. Indication for TEM: 15 (28%) benign adenoma, 25 (47%) early rectal cancer, and 13 (25%) had clinical complete response after neoadjuvant radiochemotherapy. Ten (19%) patients had no residual tumor in TEM specimen, 15 (28%) had T1, and 2 of them underwent salvage low anterior resection (LAR). Ten (19%) had T2, 4 had LAR, and 1 had abdominoperineal resection (APR). Five (9%) had a T3, 3 underwent LAR, and 2 had APR. Among the 13 (25%) after chemo-radiotherapy (CRT), 4 had salvage AR. The time from TEM to RR was 47 days (range32-70). Of 16 salvage surgeries, 8 (50%) were laparoscopic. The median operative time was 210 minutes (range165-360). Five patients had protective ileostomy. Rectal perforation occurred in 2 (12%) patients; both had a posterior location, one after CRT. Two (12%) postoperative small-bowl obstruction and three wound infections occurred. There was no perioperative mortality in any of the patients who underwent RR. The final pathology was no residual disease in 9, T3N1 in 1, T3N0 in 3, T2N1 in 1, and T2N0 in 2 patients. Eight (50%) had adjuvant chemotherapy.

Laparoscopic total mesorectal excision following TEM seems to be safe, and with no negative impact of the completeness of the resection. The concern of intraoperative specimen perforation is real, and should be dealt with meticulous technique and careful dissection, particularly after CRT.