340 the endoscopic treatment of colonic GCTs at present, benign lesions <2 cm in diameter and separated from the muscularis propria can be removed by EMR (3, 9, 14). In our analysis, the remaining four patients underwent surgical resections, based on visualization of the tumors involving the muscu- laris propria by endoscopic ultrasound, or an incidental intra- operative finding during surgery for another indication. In addition, the treatment may become surgical resection for a benign GCT because of the misinterpretation of the biopsied lesion. In surgical cases, colorectal GCTs were misinterpret- ed as a possible adenocarcinoma in the biopsy findings (10) or not differentiated from a gastrointestinal stromal tumor and a carcinoid with malignant potentials (13). Although endoscopic resections of colorectal GCTs are curative in most cases, local recurrence has also been reported (1). Neither size, mitotic activity, nor the resection margins are reliable indi- cators of recurrence. 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