GGTLC1 and hepatocellular carcinoma: Gamma‐glutamyl transpeptidase to alkaline phosphatase ratio combined with gamma‐glutamyl transpeptidase to aspartate aminotransferase ratio and alanine aminotransferase to aspartate aminotransferase ratio were effective diagnostic markers of alpha‐fetoprotein‐negative hepatocellular carcinoma, especially in patients with good liver function, early stage or small size.