Bo Bae Lee, Presenter: Nothing to Disclose

Jeong Kyong Lee MD, Abstract Co-Author: Nothing to Disclose

Jieun Byun MD, Abstract Co-Author: Nothing to Disclose

Yookyung Kim MD, PhD, Abstract Co-Author: Nothing to Disclose

To evaluate the characteristics of gallbladder (GB) polyps 10 mm or larger to predict a neoplasm in routine ultrasound (US) examinations.

A database was reviewed to search for "GB polyp" in all US examinations of abdomen for five years at a single institution. Fifty-three patients having GB polyps 10 mm or larger with follow-up images (n = 18) or pathologic diagnosis from surgery (n = 35) were included in the retrospective study. The mean duration of imaging follow-up was 46.4 months (range, 12-116 months). All US images and reports were reviewed by two readers in consensus to determine the imaging characteristics of GB polyps including the qualitative and quantitative assessment of the echogenicity, size, shape, surface, multiplicity, the presence of hyperechoic foci in the polyp, GB wall thickening adjacent to the polyps, and visibility on CT. Univariate and multivariate analysis was used to evaluate the predictors for a neoplastic polyp. Receiver operating characteristic (ROC) curve was used to determine the optimal cut-off point for size and age.

A neoplastic polyp was verified pathologically in 12 (22.6%) of 53 patients and the mean size was 23 mm (range, 10-37 mm). Remaining 41 polyps (77.4%) were verified as nonneoplastic by the stability in size on follow-up images (n = 18) or pathologic examinations (n = 23). A univariate analysis of all variables revealed that the presence of adjacent GB wall thickening (P < 0.001), larger size (≥ 17 mm, P < 0.001), older age (> 57 years, P = 0.002), the absence of hyperechoic foci in the polyp (P = 0.003), CT visibility (P = 0.014), sessile shape (P = 0.017), solitary polyp (P = 0.025), and irregular surface (P = 0.048) were significant predictors for a neoplastic polyp. In a multivariate analysis, larger size (≥ 17 mm) was a significant and independent predictor for a neoplastic polyp (P = 0.008).

The rate of malignancy is low in GB polyps even 10mm or larger (15.1%). Polyp size 17 mm or larger was the strongest predictor for a neoplastic polyp. CT visibility was a predictor for a neoplastic polyp, in addition to the established predictors. Also, polyps with inner hyperechoic foci preferred to be a nonneoplastic polyp.

Follow-up US examinations are recommended for GB polyps less than 17 mm. Cholecystectomy would be reserved for polyps 17 mm or larger.

Lee, B, Lee, J, Byun, J, Kim, Y, US Characteristics to Predict Neoplasm in Gallbladder Polyps 10 mm or Larger.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14016588.html