Can the growth rate of a gallbladder polyp predict a neoplastic polyp?

The aim of this study was to evaluate whether the growth rate of a gallbladder (GB) polyp is a predictive indicator for neoplastic polyps.

Cholecystectomy for GB polyps that are larger than 10 mm is generally recommended because of the high probability of neoplasm. In contrast, a follow-up strategy is preferred for GB polyps smaller than 10 mm. However, there are no treatment guidelines for polyps that grow in size during the follow-up period.

We retrospectively investigated 145 patients with GB polyps who underwent at least 1 ultrasonographic follow-up examination over an interval greater than 6 months, before cholecystectomy at Samsung medical center, South Korea, from 1994 to 2007. The growth rate was determined based on the change in size per time interval between 2 ultrasonographic examinations (mm/mo).

The median age of the patients was 48 years (range: 25 to 75). One hundred twenty-five non-neoplastic polyps and 20 neoplastic polyps were found. Neoplastic polyps were more frequently found in patients older than 60 years, those with hypertension, a polyp size greater than 10 mm, and a rapid growth rate greater than 0.6 mm/mo. On multivariate analysis, however, the growth rate was not related to the neoplastic nature of a polyp, but older age (>60 y) and large size (>10 mm) were significantly associated with neoplastic polyps.

Patient's age (>60 y) and large polyp size (>10 mm) were significant predictive factors for neoplastic GB polyps. GB polyps less than 10 mm in diameter do not require surgical intervention simply because they grow.