Decision for salvage treatment after transanal endoscopic microsurgery

Transanal endoscopic microsurgery (TEM) has emerged as an alternative to classic radical operation for early rectal cancer. Early rectal cancer can be treated by adequate local excision such as TEM. If there are adverse risk factors, especially poor cellular differentiation, close resection margin, or positive lymphovascular invasion or incomplete excision, a radical resection is indicated. This study aimed to clarify the factors related to recurrence for patients required to undergo a salvage operation after TEM.

This retrospective study analyzed 167 patients who underwent TEM for rectal cancer between 1994 and 2004. Of these patients, 36 with poor differentiation, mucinous carcinoma, proper muscle invasion, lymphovascular invasion, and positive resection margin were included in the analysis.

Of the 36 patients, 12 underwent a salvage operation, and the remaining 24 did not because of poor physical condition or refusal of radical surgery. There were a total of 6 (16.7%) recurrences. One (8.3%) of the 12 patients who underwent salvage surgery had systemic recurrence. Five (20.8%) of the 24 patients who did not receive surgery had recurrence (3 local recurrences, 2 distant recurrences). Analysis of the subgroups showed that 2 (28.6%) of 7 patients with lymphovascular invasion had recurrence, and that 1 patient (100%) had a T3 lesion. Three (17.6%) of 17 patients had T2 lesions.

For high-risk patients, TEM followed by radical surgery is the most beneficial in preventing local recurrence. Radical salvage surgery is strongly recommended if pathologic results after TEM show T3 lesion or lymphovascular invasion.