Transanal endoscopic microsurgery in small, large, and giant rectal adenomas

OBJECTIVE To assess the outcomes of transanal endoscopic microsurgery in small (<3 cm), large (3-5 cm), and giant (>5 cm) lesions and compare these with reports of alternative techniques. DESIGN Data from January 1998 to February 2010 were prospectively collected. Lesions were divided into 3 groups according to the maximum diameter (group A, <3 cm; group B, 3-5 cm; and group C, >5 cm) and outcomes were analyzed separately. SETTING Colorectal unit in a single-district general hospital. PATIENTS Patients diagnosed as having benign rectal adenomas. INTERVENTION Transanal endoscopic microsurgery excision. MAIN OUTCOME MEASURES Completion of excision (R0), en bloc and full-thickness excisions, complication and local recurrence rates, and disease-free survival. RESULTS A total of 320 lesions were analyzed. Overall en bloc and full-thickness excision rates were 99% and 80.7%, respectively. In the 279 benign lesions, the R0 rate was 90.3%. Outcomes for groups A, B, and C were, respectively: 9.3%, 12.8%, and 14.4% incidence of unexpected malignancy (P = .64); 95.9%, 92.2%, and 85.1% R0 resection for benign lesions (P = .19); and 7.4%, 14.9%, and 24.6% complication rates (P < .05). Overall operative mortality was 1 of 320 (0.3%). In group C, there was a higher estimated recurrence rate, therefore a lower disease-free survival than groups A and B; this difference was significant 40 months after surgery. Recurrences were associated with closeness to dentate line and advanced age (univariate analysis) and R1 resection (Cox regression). CONCLUSIONS Outcomes of transanal endoscopic microsurgery on large rectal lesions compared favorably with literature reports of alternative techniques. Postoperative complications and recurrences increased significantly with lesions larger than 5 cm.