Abstract
A 41-year-old woman was visited for examination of the gallbladder. Ultrasonography revealed nodular lesions of 10 mm in the gallbladder fundus and body, with the body lesions showing a higher signal intensity than the fundus lesions on high b-value diffusion-weighted MRI (DWI). We performed open cholecystectomy, suspecting of gallbladder cancer. Pancreaticobiliary maljunction (PBM) was diagnosed by intraoperative cholangiography. In the resected specimen, well-differentiated adenocarcinoma had spread to the entire mucosa, within which the nodular lesions in the fundus consisted of poorly differentiated adenocarcinoma, while the nodular lesions in the body consisted of endocrine cell carcinoma. We subsequently diagnosed adenoendocrine cell carcinoma of the gallbladder complicated by PBM. This case showed a variety of histological types with differing degree of differentiation. Differences in tissue were moreover reflected in signal intensity.
