Can Endoscopic Ultrasonography Differentiate Nonneoplastic from Neoplastic Gallbladder Polyps?

Abstract

The present study aimed to clarify the endoscopic ultrasonography (EUS) features of nonneoplastic (cholesterol polyps and adenomyomatosis) and neoplastic (adenoma and adenocarcinoma) gallbladder polyps and to evaluate the effectiveness and limitation of EUS in the differential diagnosis of these lesions. We retrospectively compared EUS images with histologic findings in 29 surgical cases with gallbladder polyps with a diameter of 10 to 20 mm. Those cases were indicated for surgery based on the findings of a sessile appearance, a solitary lesion, low echogenicity, and/or a lobulated surface. Six of 10 cholesterol polyps were atypically seen as partially or completely hypoechoic due to predominant proliferation of glandular epithelia. Nine of 10 cholesterol polyps demonstrated an aggregation of hyperechoic spots, which represented multiple granules of cholesterosis. All adenomyomatoses (n = 10) showed multiple microcysts, which corresponded to proliferated Rokitansky-Aschoff sinuses. However, three of nine neoplastic lesions (three adenomas and six adenocarcinomas) showed one of these signs due to concomitant cholesterosis (n = 2) or proliferated Rokitansky-Aschoff sinuses (n = 1). In conclusion, 69% (20/29) of gallbladder polyps larger than 10 mm that were preoperatively suspected of malignancy were nonneoplastic. An aggregation of hyperechoic spots and multiple microcysts are considered to be important predictive factors for cholesterol polyps and adenomyomatosis, respectively. However, we should caution that these findings can also occur in neoplastic polyps when they contain a concomitant nonneoplastic component (cholesterosis or proliferated Rokitansky-Aschoff sinuses).

Management Strategies for Gallbladder Polyps: Is It Possible to Predict Malignant Gallbladder Polyps?

“…There are several studies that endoscopic ultrasonography (EUS) has improved accuracy of the differential diagnosis of GB polyps. 6,7,9,27,28 Since this was a retrospective study, some of the patients underwent EUS and we could not evaluate as uniform diagnostic modalities. However, there are many common factors that could predict malignant GB polyps.…”

Clinical practice guidelines for the management of biliary tract cancers 2015: the 2nd English edition

“…Several reports showed that polypoid lesion is highly likely to be cancerous if it is sessile and/or solitary, its diameter is equal to or greater than 10 mm, patient's age is equal to or greater than 60 years old, and/or it grows rapidly [28][29][30][31][32]. According to these results, when polypoid lesion of the gallbladder is sessile, has a diameter equal to or greater than 10 mm and/or grows rapidly, it is highly likely to be cancerous and should be resected by cholecystectomy [28][29][30][31][32][33][34][35][36].…”

Pre-operative predictive factors for gallbladder cholesterol polyps using conventional diagnostic imaging

“…It is well known that the size of a GB polyp is related to malignancy. Many studies have reported that a GB polyp ≥ 10 mm has a high risk of being a malignancy and this size is one of the criteria for surgical intervention [4,[11][12][13] . However, we also have observed that a benign polyp, such as a cholesterol polyp, can be as large as 10 mm.…”