Endoscopic treatment of colorectal benign-appearing lesions 3 cm or larger: techniques and outcome

Colonoscopic polypectomy is the preferred technique to remove the majority of polyps. The authors evaluate feasibility, safety, and the effectiveness of endoscopic treatment of colorectal benign-appearing polyps equal to or larger than 3 cm.

Ninety-seven patients with 104 giant polyps underwent polypectomy within a nine-year period. The majority of these procedures were performed on an outpatient basis, all on unsedated patients. Gross appearance, size, location, histologic characteristics, synchronous lesions, modality, and adequacy of removal of giant polyps were analyzed. The follow-up was achieved in 89 percent of patients during a period ranging from 6 to 96 months (median, 38).

Of the 104 removed polyps, 75 (72 percent) were adenomatous, 2 (2 percent) were hyperplastic, and 27 (26 percent) were malignant polyps. Six patients had more than one giant polyp. Several additional smaller polyps were found in 52 patients and a synchronous cancer in 4. Twenty-one (20 percent) giant polyps were equal to or larger than 4 cm. Forty-nine were pedunculated, 20 were short-stalked, and 35 were sessile. Sixty-one polyps were excised in one piece, and forty-three were excised using a piecemeal technique. Only four complications (3.8 percent) were recorded; all cases were treated endoscopically. Fifty-eight (75 percent) adenomas and eighteen (67 percent) malignant polyps were completely excised. Surgery was performed in 7 of 27 patients (27 percent) with malignant polyps, where there was a doubtful, infiltrated margin or poorly differentiated cancer. Postpolypectomy surveillance permitted the detection and treatment of 25 metachronous or recurrent polyps and a metachronous cancer.

This study shows that polypectomy of giant colorectal polyps, performed by an expert endoscopist, is feasible, effective, and safe, even on an outpatient basis. The authors confirm that malignant polyps with incomplete excision, lymphovascular invasion, and poor differentiation require bowel resection. Postpolypectomy surveillance is useful for all patients who have undergone colonoscopic resection of giant adenomatous or malignant polyps.