Background: Gallbladder polyps are a risk factor for gallbladder cancer and can be an indication for cholecystectomy. Previous research has shown variable but generally poor accuracy of ultrasound in the diagnosis of gallbladder polyps. 

Methods: A search of the MEDLINE, PubMed, and Cochrane databases using the keywords “gallbladder,” “polyp,” “ultrasound,” “pathology,” and “diagnosis,” returned 1,816 articles, which were narrowed down to 14 primary sources.

Results: Of the 1,251 patients who were diagnosed with gallbladder polyp on ultrasound, 191 were confirmed as true polyps by pathology, and 85 were found to be malignant polyps. Of the 14,848 with a negative ultrasound, 30 had a true polyp on pathology. For true gallbladder polyps, standard ultrasound has a sensitivity of 70.9%, specificity of 79.9%, PPV of 15.3% (7.4% for malignant polyps), and NPV of 99.9%.

Conclusion: A systematic review of previous studies find that standard ultrasound has a very low PPV for gallbladder polyps (15.3% true polyps, 7.4% for malignant polyps). Further studies of imaging modalities and management guidelines is warranted.

A systematic review of transabdominal ultrasound in the diagnosis of gallbladder polyps.