A critical appraisal of transanal minimally invasive surgery (TAMIS) in the treatment of rectal adenoma: a 4-year experience with 51 cases.

OBJECTIVE: The aim of this study was to describe feasibility, postoperative morbidity, and histological outcome of transanal minimally-invasive surgery (TAMIS) in patients with rectal adenoma. MATERIAL AND METHODS: All patients who underwent TAMIS at a single institution from December 2011 to December 2015 were retrospectively included in the study. Feasibility was based on tumor size, distance of tumor from the anal verge, operative time, and hospital stay. Thirty-day morbidity was defined by the revised Accordion Classification system. Histological outcome included microscopic resection margin status, specimen fragmentation status, and grading of dysplasia in rectal adenoma. RESULTS: A total of 51 patients with rectal adenoma underwent TAMIS. The median tumor diameter was 32 (4-60) mm and the median distance from the anal verge 8 (3-14) cm. Median operative time was 40 (13-116) min and median length of hospital stay was 1 (0-25) days. Overall morbidity was 12% (four grade 1, one grade 2, and one grade 3 complications). 22% had a positive resection margin, whereas 31% had an indefinable resection margin status mostly due to tissue fragmentation. Median follow-up time was 7 (0-40) months. CONCLUSIONS: TAMIS is a challenging surgical technique for treatment of rectal adenoma. Our initial experience among 51 patients resulted in a high proportion of positive resection margins and a high fragmentation rate. The role of TAMIS in the treatment of rectal adenoma is to be defined through comparative studies.