BACKGROUND: The medical literature accepts local resection as a valuable option in selected cases of rectal tumors. Selection of patients requires an exact perioperative estimation of risks with clinical and histopathological examination. Transanal endoscopic microsurgery aims a safe resection of the tumoral area which leads up to the cure. AIM: To evaluate transanal endoscopic microsurgery results in a follow-up time of 18 months. METHODS: From April 2002 to April 2006, 50 patients with rectal tumors were submitted to transanal endoscopic microsurgery, chosen by clinical history and lesion characteristics. The inclusion criteria were: sessile adenomas larger than 3 cm and smaller than 8 cm, not circumferentially distributed; intra epithelial neoplasia of high degree; and rectal carcinoma pT1, and special cases of pT2. All these rectal tumors were submitted to the same surgical act. RESULTS: The final histopathological results reveal 9 adenoma, 26 intra-epithelial neoplasia of high degree, 13 carcinoma (9 pT1-4 pT2) and 2 carcinoid. The lowest age was 25 and the higher, 92 years-old. The smallest resected tumor had 64 mm(2) (carcinoid) and the largest (adenoma), 90 cm(2). Operating time was in average 90 minutes and the overall time statement, 5 days. There was one death not related with the method. One patient with low risk carcinoma pT1 presented recurrence 18 months after transanal endoscopic microsurgery and was submitted to curative rectosigmoidectomy. It was proven a residual tumor after local surgery in two patients and the most important complication was one recto-vaginal fistula. The overall complications rate was 9%. CONCLUSION: Today transanal endoscopic microsurgery is chosen as the ideal technique for the treatment of sessile adenomas, intraepithelial neoplasia of high degree and rectal carcinoma pT1.