Fibrolamellar carcinoma of the liver: a distinct entity within the hepatocellular tumors. A review.

Fibrolamellar carcinoma (FLC) of the liver is a clinicopathologic type of hepatocellular carcinoma (HCC) with a favorable prognosis with long-term survival. At variance with the usual HCC, FLC occurs predominantly in young people, both male and female, usually without preexisting liver disease. The distinctive pathologic features of FLC are presented and reviewed. Both gross and microscopic findings suggest that FLC is the malignant counterpart of focal nodular hyperplasia that may arise from preexisting focal nodular hyperplasia. The storage of copper and fibrinogen inside tumor cells is a peculiarity of FLC, and it appears to be in a close relationship with the oncocytic appearance of FLC cells having a deeply eosinophilic, finely granular, mitochondrion-rich cytoplasm. All other immunohistological and ultrastructural findings strongly support the high degree of differentiation of FLC.