The aim of this study was to review experience with transanal endoscopic microsurgery (TEM) and to assess its applicability to an existing practice of colorectal surgeons. Patients undergoing TEM excision of rectal lesions from March 1997 through May 1999 were selected for this study. Medical records were reviewed retrospectively to obtain pertinent data, including indications for TEM, tumor size, distance from anal verge, duration of operation, completeness of tumor resection, postoperative complications, duration of stay and follow-up, and recurrence. Thirty-one patients underwent TEM during the 2-year period. Indications for TEM included benign disease in eight patients and cancer in 23 patients. Mean distance of the tumor from the anal verge was 8.3 cm. Mean size of the lesion was 2.8 cm, and mean specimen size was 4.5 cm. Larger specimen sizes allowed for tumors to be removed with negative margins (97%) in all cases but one. Mean duration of operation was 140 minutes (including set-up time), and mean duration of hospital stay was 1.2 days. Major postoperative complications occurred in one patient. Mean duration of follow-up was 15 months, and recurrence developed in two patients during this period. Transanal endoscopic microsurgery excision of rectal lesions with negative margins was possible in 97% of cases with minimal morbidity and a short-duration hospital stay. Follow-up was too brief to evaluate recurrence, but the thoroughness of resection of tumor in a high proportion of cases is promising.