Abstract
A 59-year-old man presented with appetite loss and jaundice was diagnosed as having middle bile duct carcinoma following close exploration. Pancreatoduodenectomy was scheduled. Upon laparotomy, four nodules which were grayish white in color and several millimeters in size were identified on the liver surface. Hepatic metastasis of cholangiocarcinoma was suspected and biopsy was performed. On frozen section diagnosis, malignant neoplasms were suspected so that surgical resection was discontinued. Histopathology of the permanent specimen, however, suggested that biliary microhamartoma (von Meyenburg complex) was most likely. Thereafter pancreatoduodenectomy was performed. Cholangiocarcinoma was moderately differentiated tubular adenocarcinoma in Stage III and its histologic features were different from those of the nodules of the liver. The patient had been given TS-1 orally for about one year as postoperative adjuvant chemotherapy. Serum level of CA19-9 elevated two years after the operation and TS-1 regimen resumed for suspected recurrence. The CA19-9 level once decreased, but started to elevate again three years after the operation. An abdominal CT scan suggested possible occurrence of lymph node or local metastasis, but no hepatic metastasis was demonstrated.
Biliary microhamartomas are rare and often pose a problem of differentiation from hepatic metastasis.
