Transanal Endoscopic Microsurgery (TEM) for rectal GI stromal tumor.

[BACKGROUND] Transanal endoscopic microsurgery (TEM) is effective in treating adenomas and select early rectal cancers. Our objective is to evaluate TEM in treating early rectal GISTs.

[METHODS] Patients were identified in a prospective database with pathology confirmed rectal GIST prior to TEM over 10 years. Demographic, pathologic, operative and follow-up data was analysed and presented with descriptive statistics.

[RESULTS] 7 cases of rectal GIST were treated with TEM with a follow-up time of 31 months (0-71). Median tumor distance from the anal verge was 4 cm (2.5-6) and median tumor size was 3 cm (2-5.7). Negative margins were achieved in 4/7 patients. Those with positive margins were treated with repeat TEM or imatinib. 1 patient had local recurrence successfully treated by TEM.

[CONCLUSIONS] Overall, TEM is safe for locally excising GISTs. As rectal GISTs are rare, a multicenter registry may better elucidate outcomes with this treatment.