AFP and cholangiocarcinoma: The serum level of AFP peaks during embryogenesis and rapidly decreases after birth but re-increases in the presence of hepatocellular cancer or germ cell tumors, making it an evaluable biomarker for these two types of malignancies.342 Cells with high AFP levels exhibit stem-like properties in pancreatic cancer, cholangiocarcinoma, and hepatocellular cancer, making it a potential CSC marker for these types of cancer.343–345