TTF1 and hepatocellular carcinoma: Some of the histochemical markers used for HCC diagnosis include pCEA, CD10, alpha fetoprotein (AFP), hepatocyte paraffin1 (hepPar1), cytoplasmic thyroid transcription factor-1 (TTF1), glutamine synthetase, GPC3, CK8 and CK18, but unfortunately none of them is specific of early stage HCC.