The level of CEA > 5 ng / ml was defined as abnormal (CEA (+)), while the cutoff for the CA 19 - 9 was set at 37 U / mL (CA 19 - 9 (+)).
Nồng độ CEA > 5 ng / ml là tiêu chuẩn CEA (+). Nồng độ CA 19-9 > 37 U / mL là tiêu chuẩn CA 19-9 (+).