18 F-FDG PET/CT Findings Mimicking Gallbladder Metastasis From a Rectal Adenocarcinoma: Rare Synchronous Gallbladder and Rectal Cancer.

Abstract

Metastasis from rectal adenocarcinoma (RAC) to the gallbladder (GB) is rare. Differentiating GB metastasis from primary gallbladder cancer (GBC) is important for treatment planning. A patient diagnosed RAC with 18 F-FDG PET/CT found suspicious findings of GB metastasis. However, after surgery was found to be primary GBC. The incidence of multiple primary tumors (MPTs) varies 2.4%-8%. In this case report, we would like to present 18 F-FDG PET/CT findings of rare synchronous coexistence of GBC and RAC, and also that, although rare, metastasis from the RAC to the GB should definitely be kept in mind.