Gallbladder polyps

This week we have two excellent images of gallbladder polyps. The first image is brought to us by Drs. Maureen Joyner and Sean Lowe, the second image by Drs. Ibithal Alattas and Elizabeth Iledare.  Gallbladder polyps can easily be confused with stones, but there are two key differences to help you distinguish them. First, polyps are soft tissue masses, so they will not cause the shadowing that is typically seen with stones.  Second, polyps are adherent to the wall of the gallbladder and will not be mobile if you have the patient change position. The position of polyps can be important as they can cause acute cholecystitis if they are lodged in the neck of the gallbladder.  

The vast majority of polyps seen on US are benign, so we shouldn’t frighten our patients, but it’s important that we arrange appropriate outpatient follow-up for radiology performed ultrasound imaging to formally characterize the polyp.  In a recent study of patients with biopsied polyps seen on ultrasound, significant predictors of malignancy included age >52, presence of associated gallstones, polyp size >9mm, evidence of liver invasion, or wall thickening.  

Reference:

Gallbladder Lesions Identified on Ultrasound. Lessons from the Last 10 Years.

Konstantinidis IT, Bajpai S, Kambadakone AR, Tanabe KK, Berger DL, Zheng H, Sahani DV, Lauwers GY, Fernandez-Del Castillo C, Warshaw AL, Ferrone CR.

J Gastrointest Surg. 2011 Nov 23. [Epub ahead of print] PMID:22108768