GPT and cancer: In other cancers that invade the liver, measurable changes have been noted in liver function serum markers alanine transaminase (ALT), aspartate transaminase (AST), total bilirubin (TBIL), gamma glutamyltransferase (GGT), alkaline phosphatase (ALP), albumin (ALB), and carcinoembryonic antigen (CEA) [44,45,46].