Recurrence after transanal endoscopic microsurgery for large rectal adenomas

BACKGROUND:Transanal endoscopic microsurgery (TEM) has revolutionized the technique and outcome of transanal surgery, becoming the standard of treatment for large sessile rectal adenomas. Nevertheless, only a few studies have evaluated the risk factors for local recurrence in order to recommend a "tailored" approach. The aim of this study was to identify predictor variables for recurrence after TEM to treat rectal adenoma. METHODS:This study is a retrospective analysis of a prospective database of patients treated for large sessile rectal adenomas by TEM at our institution, with a minimum follow-up of 12 months. Age, gender, tumor diameter, distance from the anal verge, degree of dysplasia, histology, and margin involvement were investigated. RESULTS:Between January 1993 and July 2010, 293 patients with a rectal adenoma ≥3 cm underwent TEM. Postoperative morbidity rate was 7.2 % (21/293) and there was no 30-day mortality. Over a median follow-up period of 110 (range = 12-216) months, 13 patients (5.6 %) were diagnosed with local recurrence. The median time to recurrence was 10 (range = 4-33) months, with 76.9 % of recurrences detected within 12 months after TEM. At univariate analysis, tumor diameter (p = 0.007), and positive margins (p < 0.001) were shown to be significant risk factors, while multivariate analysis indicated the presence of positive margins as the only independent predictor of recurrence (p = 0.003). CONCLUSIONS:TEM provides excellent oncological outcomes in the treatment of large sessile benign rectal lesions, assuring a minimal risk of resection margin infiltration at pathology examination, which represents the only risk factor for recurrence.