Gallbladder polyps: Can they be cancerous?

Gallbladder polyps are growths that protrude from the lining of the inside of the gallbladder. They typically cause no noticeable symptoms and are often detected on imaging studies done for other reasons. Polyps can be cancerous, but they rarely are. About 95% of gallbladder polyps are benign.

The size of a gallbladder polyp can help predict whether it's cancerous (malignant) or noncancerous (benign). Small gallbladder polyps that are less than 1/2 inch — about 10 millimeters (mm) — in diameter are unlikely to be cancerous and generally don't require treatment.

However, even for smaller polyps, your doctor would suggest follow-up examinations to look for changes that may be an indication of cancer. This is commonly done using standard abdominal ultrasound or, less commonly, with an endoscopic ultrasound or a CT scan. If a gallbladder polyp increases in size by 2 mm or more, your doctor may recommend surgical removal of the gallbladder (cholecystectomy).

Gallbladder polyps larger than 1/2 inch (about 10 mm) in diameter are more likely to be cancerous or turn into cancer over time, and those larger than 3/4 inch (18 mm) in diameter may pose a significant risk of being malignant. Treatment of larger gallbladder polyps includes surgical removal of the gallbladder (cholecystectomy). Again, malignant polyps are extremely rare. Only about 5% of gallbladder polyps are cancerous.

Your doctor may also recommend cholecystectomy if you have a gallbladder polyp of any size accompanied with gallstones or for a polyp greater than 1/3 inch (about 8 mm) if you have a condition known as primary sclerosing cholangitis.