Does Cancer Risk in Colonic Polyps Unsuitable for Polypectomy Support the Need for Advanced Endoscopic Resections?

There is a continuing debate on the best approach for endoscopically benign large polyps that are unsuitable for conventional endoscopic resection. This study aimed to estimate the cancer risk in patients with endoscopically benign unresectable colonic polyps referred for surgery.

We assessed patients with an endoscopic diagnosis of benign adenoma deemed not amenable to endoscopic removal, who underwent colectomy between 1997 and 2012. Patients with preoperative diagnoses of cancer, inherited polyposis syndrome, inflammatory bowel disease, and synchronous pathology requiring surgery were excluded.

There were 439 patients (220 [50.1%] men; median age 67 years [range 27 to 97 years]) who underwent colectomy. Of 439 patients, 346 (79%) underwent preoperative endoscopy at our institution. Most of the polyps were located in the right colon (394 of 439, 89.7%), with the majority in the cecum (199 of 394, 45.3%). Polyp morphology was as follows: sessile (n = 252, 57.4%), pedunculated (n = 109, 24.8%), and flat (n = 78, 17.8%). Endoscopic pathology revealed high-grade dysplasia in 88 (20%) patients. Mean colonoscopic and postoperative polyp sizes were 3.0 cm (range 0.3 to 10 cm) and 2.7 cm (range 0 to 11 cm), respectively (p < 0.001). Final surgical pathology revealed cancer in 37 patients (8%). Polyp location, morphology, and histologic types were similar between the benign and malignant polyps. Cancer stages were: stage I (23 patients), stage II (11 patients), and stage III (3 patients).

For the majority of endoscopically benign colonic polyps, an oncologic colonic resection may be unnecessary, so advanced endoscopic resection techniques or laparoscopic-assisted polypectomy should be considered. When bowel resection is needed, the resection should be performed, obeying oncologic principles and techniques.