COMBINED HEPATOCELLULAR-CHOLANGIOCARCINOMA - A CLINICOPATHOLOGICAL STUDY

Combined hepatocellular-cholangiocarcinoma (HCC-CC) is an uncommon for m of primary liver cancer having features of both hepatocellular and b iliary epithelial differentiation. We reviewed 21 cases of this tumour diagnosed between 1972 and 1996 (patient age range 16-79 years; mean patient age 49.7 years; 18 male and three female patients). Histologic ally, the majority (n = 18) of tumours were 'mixed' tumours, in which areas of hepatocellular and biliary epithelial differentiation were in timately mixed within the same rumours. Two patients had separate tumo urs in which discrete nodules of HCC and CC occurred in the same liver s. One patient had a 'fibrolamellar' tumour that histologically simula ted the fibrolamellar variant of HCC, but some of the tumour cells wer e mucin-producing cells. Of the 21 cases, mucin was demonstrable in 16 and, in the few mucin-negative rumours, electron microscopic studies confirmed the presence of the dual differentiation. The tumours freque ntly exhibited an invasive character with frequent venous permeation, direct invasion into adjacent liver parenchyma and tumour microsatelli te formation, similar to that of ordinary HCC. Histological evidence o f cirrhosis or chronic hepatitis was present in 77.8% of patients and 75% of patients were hepatitis B surface antigen positive. Raised seru m alpha-fetoprotein (AFP) levels (above 300 ng/mL) were present in 61. 5% of patients and AFP was detected immunohistochemically in 55% of ru mours. The overall survival times of patients with HCC-CC were short. In conclusion, HCC-CC showed clinical and pathological features more a kin to those of ordinary HCC than to CC.