Prevalence

• Gallbladder polyps can be common and are usually found by ultrasound, according medicine.net. Usually they are small and do not exhibit symptoms. Cholesterol polyps make up 50 to 60 percent of gallbladder polyps, according to the "Gallbladder Tumor" overview on medscape.com. The presence of cholesterol polyps is called cholesterosis.
  
  

Size

• Generally, cholesterol polyps are multiple lesions and usually smaller than 10 mm, said medscape.com.
  
  

Cause

• Cholesterol polyps could originate from a cholesterol metabolism defect, according to the "Gallbladder Tumor" overview.
  
  

Other gallbladder polyps

• Cholesterosis with fibrous dysplasia of gallbladder, adenomyomatosis, hyperplastic cholecystosis and adenocarcinoma are the four other types of gallbladder polyps.
  
  

Malignant or benign tumors

• Polyps can benign or malignant. Cholesterol polyps are the most common benign non-neoplastic (pseudotumors), according to the website uptodate.com. Adenomatous polyps are potentially malignant, according to medscape.com.
  
  

Potentially problematic

• Although not usually cancerous, "(o)ccasionally, cholesterol polyps can slough off and cause biliary colic from cystic duct obstruction or acute pancreatitis by blocking the common bile duct," says medscape.com.