Transanal endoscopic microsurgery: long-term experience, indication expansion, and technical improvements

Abstract

This study aimed to review the authors' 16-year experience with transanal endoscopic microsurgery (TEM). Mortality, morbidity, recurrence rate, and functional outcome were assessed. New indications and technical improvements are presented. From November 1991 to August 2008, 123 patients (72 men and 51 women; median age, 68 years; range, 21-91 years) underwent TEM for excision of 105 adenomas with low- or high-grade dysplasia, 9 invasive adenocarcinomas (5 curative and 4 palliative resections), 2 neuroendocrine tumors, and 2 extramucosal lesions. Five additional patients had excisional biopsies, allowing staging after previous endoscopic resection. Most of the resections were full-thickness rectal resections using electrocautery or, more recently, the Harmonic scalpel. The latest mucosectomies were performed using the endoscopic submucosal dissection (ESD) technique. In addition, nontumoral indications included pelvic abscess (7 patients) and rectal strictures, which were either anastomotic or chemical. Pelvic abscesses were drained transrectally, whereas rectal stenoses were treated by strictureplasty. Foreign object retrieval and collagen plug placement for anal fistulas were performed using TEM in three patients. No mortality occurred. One intraoperative rectal perforation required conversion to laparotomy. The postoperative complications included one pneumoperitoneum, which was treated medically, and one rectal perforation requiring Hartmann's procedure. In the polyp subgroup, six patients (6/91, 7%) experienced local recurrence. Pelvic abscesses were successfully treated, and stenosis did not recur after strictureplasty. Anorectal manometry showed functional alterations without significant clinical impact. The findings showed TEM to be a safe and effective procedure for local excision of rectal lesions with a low recurrence rate and minimal consequences in terms of anorectal function. In addition, TEM proved to be feasible and effective for pelvic abscess drainage and rectal stenosis treatment. New technologies such as the Harmonic scalpel and ESD increase the precision already offered by this approach.