Recurrence after transanal endoscopic microsurgery for large rectal adenomas

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.

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.

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).

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.