Per-anal excision of large, rectal, villous adenomas

Considering the malignant potential of villous adenoma of the rectum, complete resection at the first intervention is desirable and yet many series suggest that a high recurrence rate must be expected. The experience of one colorectal surgeon in the management of this condition is described.

Between 1993 and 2000, 50 patients underwent per-anal resection of villous adenoma. The procedure was conducted in the prone jackknife position unless contraindicated, with dissection performed using a diathermy blade, with particular attention to circumferential and deep margins of excision.

The mean distance of the proximal margin of the tumor from the dentate line was 5.6 (range, 0.5-11) cm. The mean length of the tumor was 5.2 (range, 0.5-9) cm. Mean anesthetic time was 27 (range, 10-110) minutes, and median hospital stay was two (range, 1-14) days. There was no significant perioperative morbidity and no mortality. On histology of ten patients, there were foci of adenocarcinoma. Excision was complete histologically in 49 patients. The median follow-up was 30 (range, 6-91) months. The patient with incomplete excision developed a probable recurrence after six months, which was ablated with diathermy (residual tumor rate, 2.1 percent). Two patients have subsequently developed villous adenoma at different sites within the rectum (metachronous tumor rate, 4.3 percent).

Many series of this procedure report recurrence in up to 36 percent and significant complication in up to 19 percent of patients. Transanal endoscopic microsurgery has achieved recurrence rates of 2.8 percent and low complication rates but for economic reasons has failed to find a widespread role. This article demonstrates that large, villous tumors of the low and mid rectum can be simply and effectively treated by per-anal resection with recurrence rates equivalent to transanal endoscopic microsurgery.