Polypoid Lesions of the Gallbladder: Disease Spectrum with Pathologic Correlation

Abstract

Gallbladder polyps are seen on as many as 7% of gallbladder ultrasonographic images. The differential diagnosis for a polypoid gallbladder mass is wide and includes pseudotumors, as well as benign and malignant tumors. Tumefactive sludge may be mistaken for a gallbladder polyp. Pseudotumors include cholesterol polyps, adenomyomatosis, and inflammatory polyps, and they occur in that order of frequency. The most common benign and malignant tumors are adenomas and primary adenocarcinoma, respectively. Polyp size, shape, and other ancillary imaging findings, such as a wide base, wall thickening, and coexistent gallstones, are pertinent items to report when gallbladder polyps are discovered. These findings, as well as patient age and risk factors for gallbladder cancer, guide clinical decision making. Symptomatic polyps without other cause for symptoms, an age over 50 years, and the presence of gallstones are generally considered indications for cholecystectomy. Incidentally noted pedunculated polyps smaller than 5 mm generally do not require follow-up. Polyps that are 6-10 mm require follow-up, although neither the frequency nor the length of follow-up has been established. Polyps that are larger than 10 mm are typically excised, although lower size thresholds for cholecystectomy may be considered for patients with increased risk for gallbladder carcinoma, such as patients with primary sclerosing cholangitis.

Tumefactive Gallbladder Sludge at US:Prevalence and Clinical Importance

“…In clinical practice, when tumefactive sludge is incidentally detected at US examination, observation, short-term follow-up with US, or further evaluation with additional imaging modalities usually is performed. This may include contrast material-enhanced US, computed tomography (CT), and magnetic resonance (MR) imaging (1,2). However, no clinical guidelines have been published regarding the treatment of patients with tumefactive sludge seen at US, and to our knowledge, no study exists regarding the rate of malignancy in patients found to have tumefactive sludge at US.…”

“…The institutional review board granted approval for the study and waived the requirement for U ltrasonography (US) has a primary role in the imaging of gallbladder diseases including polyps, cholelithiasis, and sludge (1). Although gallbladder polyps and gallstones are relatively common, with a prevalence of 3%-7% and 10%, respectively, at abdominal US, biliary sludge is quite rare in asymptomatic healthy adults (2,3), with a reported prevalence of 0.18%-0.27% (4,5). However, its incidence can be higher in specific clinical situations such as pregnancy (6), total parenteral nutrition (7), rapid weight loss (8), and prolonged fasting in the intensive care unit (9).…”

The EFSUMB Guidelines and Recommendations for the Clinical Practice of Contrast-Enhanced Ultrasound (CEUS) in Non-Hepatic Applications: Update 2017 (Long Version)

“…Polypoid gallbladder lesions are commonly seen on US (2.6 % -12.1 % of cholecystectomy specimens) [456]. In primary sclerosing cholangitis and gastrointestinal polyposis syndromes, 60 % of gallbladder polyps are malignant [457].…”

“…In primary sclerosing cholangitis and gastrointestinal polyposis syndromes, 60 % of gallbladder polyps are malignant [457]. Malignancy in gallbladder polyps between 6 -10 mm is extremely rare, while polyps > 10 mm are regarded as preinvasive adenomas and papillary neoplasms [456,458]. Adenomas have a wider vascular stalk, thought to be significant, that is best seen on CEUS [456,459].…”

“…Malignancy in gallbladder polyps between 6 -10 mm is extremely rare, while polyps > 10 mm are regarded as preinvasive adenomas and papillary neoplasms [456,458]. Adenomas have a wider vascular stalk, thought to be significant, that is best seen on CEUS [456,459]. It remains unclear if CEUS can contribute to the differentiation between polyps, adenomas and noninvasive gallbladder carcinoma [441,460].…”