Gallbladder polyps are growths that protrude from the lining of the inside of the gallbladder. Polyps can be cancerous, but they rarely are.
The size of a gallbladder polyp can be a useful predictor of whether it's cancerous (malignant) or noncancerous (benign). Gallbladder polyps that are less than 1/2 inch (about 10 millimeters) in diameter are unlikely to be cancerous and generally don't require treatment. However, your doctor may suggest follow-up examinations to look for changes in gallbladder polyps that may be an indication of cancer. This can be done using standard abdominal ultrasound or endoscopic ultrasound.
Gallbladder polyps larger than 10 millimeters (mm) in diameter are more likely to be cancerous. Treatment of larger gallbladder polyps may include surgical removal of the gallbladder (cholecystectomy). Polyps larger than 18 mm in diameter may pose a significant risk of being malignant. Your doctor may also recommend cholecystectomy if you have a gallbladder polyp of any size accompanied with gallstones.