Polyp on ultrasound: now what? The association between gallbladder polyps and cancer

The association between gallbladder polyps (GBP) and gallbladder cancer (GBC) is unclear. We sought to determine the association between preoperative diagnosis of GBP on imaging and GBC. A retrospective review of patients over 9 years was conducted using International Classification of Diseases, 9th Revision codes for GBP and GBC who underwent cholecystectomy at our institution. Demographics, imaging findings, and pathology results were recorded. A total of 2416 patients underwent cholecystectomy during the study period. Twenty-seven had an operation for GBP either as a result of concern for size or symptoms. Polyp sizes were categorized as less than 1 cm, 1 to 2 cm, or 2 cm or greater. Twenty-four patients in this group (88.9%) had no evidence of high-grade dysplasia or cancer and all of these benign polyps were 2 cm or less on imaging. One patient with a 2.4-cm polyp had high-grade dysplasia, and two patients with polyps over 3 cm had adenocarcinoma. During the same period, 20 patients had an operation for GBC with two patients common to the polyp group. The group of patients with noncancerous polyps was significantly younger than the cancer group (polyps and no polyps). The cancer group was more likely to be symptomatic. Therefore, polyps over 2 cm should be removed given the risk of high-grade dysplasia and cancer above this size. Polyps less than 2 cm were not associated with high-grade dysplasia or cancer and thus surgery may not be required. Intermediate- and small-sized polyps can be monitored with serial ultrasound, especially in younger, asymptomatic patients in whom the risk of malignancy is low.