This is a gallbladder involved by well differentiated invasive adenocarcinoma with mucinous differentiation. Without apparent adenocarcinoma in situ or epithelial dysplasia in the nearby surface mucosal surface, it ould be impossible to tell whether this involvement is primary or by direct extension of an ampullary, biliary or pancreatic adenocarcinoma.

 腺癌。

 腺癌

 腺癌

     腺癌。