Surgical approach to rectal carcinoma by transanal endoscopic microsurgery and endocavity irradiation

Transanal endoscopic microsurgery (TEM) is one form of minimally invasive surgery that provides transanal access to lesions in the proximal part of the rectum. Traditional abdominal techniques require segmental resection by low anterior resection or abdomino-perineal resection. The TEM technique is possible because of technology that solves two problems with transanal approach to tumors in the rectum: first the long narrow instruments reach the length of the rectum; second, insufflation of CO2 into a gas tight system maintains distention of the rectal walls for exposure. Criteria for local excision of rectal carcinoma are the same as those used for transanal excision in the lower rectum for decades. Transanal ultrasonogtaphy should be performed preoperatively in order to confirm the depth of the penetration. The local recurrence rate for TI carcinoma (low risk carcinoma) is around 5-9%. In order to diminish potential local recurrences we used postoperatively endocavitary irradiation. Preliminary results of 16 patients with localized rectal cancer treated by TEM and postoperatively irradiation are reported.