Transanal endoscopic microsurgery (TEM) allows local excision of rectal tumors located 4 to 18 cm above the anal verge. The technique is not yet generally established because of the necessary special instrumentation and tools, the unusual technical aspects of the approach, and the stringent patient selection criteria. The aim of this prospective, descriptive study was to analyze the currently accepted indications for TEM and to evaluate the use of this procedure for treating rectal cancer. Over a 4-year period 50 patients aged 31 to 86 years (mean 64 years) underwent TEM for treatment of rectal tumors located 12 cm above the anal verge (range 4-18 cm). The local complication rate was 4%. Altogether, 76% of lesions were benign, and 24% were T1 and T2 tumors. Of 12 cancer cases, 4 required reoperation by total mesorectal resection; the other 8 are currently under follow-up management. Over the follow-up period of 30.6 months (range 11-54 months) the recurrence rate of T1 tumors was 8.3%. TEM is a minimally invasive surgical technique that may benefit a small, specific population of patients with rectal tumors. Compared with conventional transanal resection, TEM provides superior exposure of tumors higher up in the rectum (i.e., up to 18 cm from the anal verge). The greater precision of resection combined with low morbidity (10%, relative to that of anterior resection) and short duration of hospitalization (5.5 days) make this technique a reliable and in some cases more effective surgical approach than laparotomy and low anterior resection.