Abstract
We reviewed the 4 cases of patients with carcinoma of the cystic duct based on the clinicopathological records. Histopathological findings (i. e., H. E. staining and cell proliferating potency assessed by MIB-1 staining) for both main and invasive regions of the carcinoma were compared to those of 12 patients with gallbladder carcinoma) and 6 patients with middle bile duct carcinoma, The US showed no swelling of the gallbladder in 3 cases, which were diagnosed later as atrophic gallbladder, adenomyomatosis of the gallbladder, and dystelectasis due to the carcinoma infiltration. The CT showed that in the 2 cases showing nodular-type, the tumors were enhanced by contrast medium. The direct cholangiography failed to demonstrate the right hepatic duct and gallbladder in a case of advanced carcinoma. The regions of biliary tree distal to the obstruction could be evaluated by MRCP. The angiography showed tumor stains in the 2 cases of advanced carcinomas. The pathology revealed that papillary adenocarcinoma predominated. The carcinoma of the cystic duct at advanced stages was observed to often invada into perineural space. The perineural invasion was more frequent in carcinoma of the cystic duct than in gallbladder carcinoma, the finding making cystic duct carcinoma rather similar to bile duct carcinoma. Thus, it is suggested that papillary carcinoma is transformed to tubular adenocarcinoma when extending out of the cystic duct. In this transformation, the carcinoma exhibited the high value of cell proliferating potency when assessed by MIB-1 staining. These results suggest that in carcinoma of the cystic duct the tumors extending out of the cystic duct become aggressive and therefore offer poorer prognosis.
