Polypoid lesions of the gallbladder: diagnosis and followup

Polypoid lesions of the gallbladder (PLG) are commonly seen on ultrasonography (US), but optimal management of this problem is ill-defined. The aims of this study were to assess the natural history and the histologic characteristics of US-detected PLG.

Patients with PLG detected by abdominal US were identified retrospectively. Patients with infiltrative masses suspicious for gallbladder cancer were not included. Histologic findings were analyzed in patients who underwent cholecystectomy, and change in polyp size was determined in patients who underwent serial US imaging.

From 1996 through 2007, 417 patients with PLG detected on US were identified. Two hundred twenty-nine patients (55%) were women, and median age was 59 years (range 20 to 94 years). Two hundred sixty-five patients (64%) were found to have PLG on US during the workup of other unrelated disease; 94 patients (23%) had abdominal symptoms. Ninety-four percent of patients had PLG< or =10 mm, and 7% had PLG>10 mm; 59% of patients had a single polyp and 12% had gallstones. Among 143 patients who had repeat US followup, growth was observed in only 8 patients (6%). Cholecystectomy (n=80) revealed that most patients had either pseudopolyps (58%) or no polyp (32%). Neoplastic polyps (adenoma) were found in 10% of patients. In situ cancer was seen in one patient with a 14-mm lesion.

Small PLG (< or =10 mm in diameter) detected by US are infrequently associated with symptoms and can be safely observed. The risk of invasive cancer is very low, and was not seen in any patient in this study.