Transanal endoscopic microsurgery (TEM) is a minimally invasive surgical technique for performing local excision of rectal lesions in the mid and upper rectum that would otherwise be inaccessible for local excision by the direct transanal approach. In the absence of this approach, low anterior resection would be required, which is major abdominal surgery. The justification for excising adenomas of the colon and rectum is their malignant potential, which correlates with the size of the lesion. This retrospective review examines our experience using TEM for excision of adenomas of the rectum from February 1991 to the present. The decision for using TEM is based on a precise localization of the lesion with particular attention to the upper margin of the lesion and its diameter. A total of 56 adenomas were removed. The average diameter was 4.9 cm (range, 3-8 cm). The average distance from the anal verge was 7.92 cm (range, 5-12 cm). Carcinoma in situ was seen in 7 lesions, and the remaining lesions were benign. Morbidity was minimal, with one conversion to an open procedure for an intraperitoneal perforation that required a low anterior resection. No patient required transfusion and there was no mortality. The hospital stay was short, with half of the patients being discharged the same day. The average cost from July 1996 to December 1999 was $7775 for TEM versus $34,018 for LAR. Subsequent follow-up average was 38.8 months (range, 1-100 months), during which time two patients had recurrence of their adenomas. This was successfully treated with reexcision. In conclusion, TEM is an accurate, safe, and relatively inexpensive technique when compared to low anterior resection. This technique significantly reduces the proportion of adenomas requiring abdominal surgery.