Hepatocolangiocarcinoma combinado. Claves para su diagnóstico anatomopatológico

Combined hepatocellular-cholangiocarcinoma is a rare primary hepatic tumour, characterized by unmistakable, intimately mixed elements of both hepatocellular carcinoma and cholangiocarcinoma. We report 2 cases in which the preoperative diagnosis was cholangiocarcinoma (case 1) and hepatocellular carcinoma (case 2). However, the microscopy of the surgical specimen revealed components of typical hepatocellular carcinoma as well as cholangiocarcinoma in both cases. Moreover, case 2 showed areas of undifferentiated cells expressing stem cell markers. As the classification of these tumours has recently changed, histopathological keys for their correct diagnosis would prove helpful. To this end, we have reviewed the pertinent literature in search of such diagnostic aids.