A case of undifferentiated carcinoma of the gallbladder with anomalous arrangement of the pancreaticobiliary ductal system

Anomalous junction of the pancreaticobiliary duct (AJPBD) is a congenital a nomaly associated with gallbladder carcinoma. Especially patients with nonc ystic dilatation and without dilatation of the biliary tract are at risk of gallbladder carcinoma. A 56-year-old woman with advanced gallbladder cance r associated with AJPBD but without dilatation of the biliary tract was tre ated at our hospital. Although histologically cancer cells remained in the layer of the proprial mucosa, extensive metastases to lymph nodes including the paraaorta and peripancreas were detected. According to the TNM classif ication this case was of Stage IVB. The cancer consisted of medullary round cells, and was diagnosed as undifferentiated carcinoma. After surgery poor prognosis was expected, but three years have elapsed with no recurrence. T he case is of interest because of two points of discrepancy: the primary ca ncer did not show deep invasion but demonstrated extensive lymph node metas tases; the cancer was histologically malignant but prognosis was relatively good.