Bile duct adenomatosis of the liver: a misleading finding on surgical exploration of the abdomen.

A patient found to have the unusual condition of bile duct adenomatosis of the liver is discussed. The liver was "peppered" with small subcapsular nodules, which microscopically appeared as multilocular cysts, lined with cuboidal cells similar to those of normal bile ducts. This benign condition most likely is developmental in etiology, and may present early in life as polycystic liver disease, or later when discovered as an incidental finding at laparotomy or autopsy. Its differentiation from metastatic disease by the surgeon on gross examination of liver alone may not be possible.