Initial Experience with Transanal Endoscopic Microsurgery: the Need for Understanding the Limitations

Transanal endoscopic microsurgery is an alternative to transanal excision or radical surgery for benign and carefully selected malignant rectal tumors. Advantages over transanal excision include better visualization, access to more proximal lesions, higher likelihood of negative margins, and lower recurrence rates. Compared to radical resection, patients experience lower rates of morbidity and mortality but may have higher rates of local recurrence. A review of a prospectively maintained database of patients scheduled for transanal endoscopic microsurgery was performed. Ninety-three patients underwent 96 procedures for 13 carcinoid tumors, 1 submucosal mass, 46 adenomas, 12 in situ adenocarcinomas, and 21 invasive adenocarcinomas. Of these cases, 81.2% was successfully completed. There were nine complications (11.5%). Final pathology demonstrated 33 in situ and invasive adenocarcinomas. The mean follow-up was 25.9 months. The four recurrences (12.1%) occurred in: one tubulovillous adenoma, two in situ carcinomas, and one T2 lesion. Transanal endoscopic microsurgery is appropriate for benign lesions such as carcinoid tumors and adenomas and can also be curative in carefully selected patients with early-stage invasive rectal cancer. In cases of invasive adenocarcinoma, it should be reserved for low-risk cancers in patients who accept the possible increased risk of recurrence.