Hypoechoic foci on EUS are simple and strong predictive factors for neoplastic gallbladder polyps

Background: EUS is an accurate imaging modality for delineating gallbladder (GB) structures; however, its clinical use in differentiating neoplastic GB polyps from nonneoplastic polyps is limited. Thus, we sought to characterize neoplastic GB polyps by analyzing unique EUS features. Our analysis revealed variably shaped, relatively hypoechoic portions in the core of polyps compared with general background echogenicity. Objective: Our purpose was to make a differential diagnosis between neoplastic and nonneoplastic GB polyps of less than 20 mm by use of EUS variables, including hypoechoic foci. Design: Retrospective single-center study. Setting: University teaching hospital. Patients: Patients (n = 88) underwent preoperative EUS and cholecystectomy for GB polyps smaller than 20 mm. Results: Hypoechoic foci were found in 30 of 33 patients (91%) with neoplastic polyps and 6 of 55 (11%) with nonneoplastic polyps. In a multivariate analysis, hypoechoic foci were the only significant predictive factor for neoplastic polyps (odds ratio [OR] 55.4, 95% CI, 8.26-371, P < .001); the sensitivity and specificity were 90% and 89%, respectively. In addition, polyps >15 mm had an increased risk of malignancy (OR 21.7, 95% CI, 2.35-201, P = .007), as did those with hypoechoic foci (OR 10.9; 95% CI, 1.01-117, P = .049). Limitations: Retrospective review of selected patients from a tertiary medical center. Conclusions: The presence of hypoechoic foci on EUS is a strong predictive factor for neoplastic polyps. EUS may be useful in developing a treatment strategy for GB polyps.