Cancer markers are proteins that may be produced by cells that show increased turnover. Cancer markers have variable test sensitivities and specificities and should be taken and interpreted within the context of the patients' medical history. Tumour MarkersDescription Colon & Lungs (Carcinoembryonic Antigen – CEA)CEA may be elevated in selected cases of cancers of the large intestine & lung Smokers may also have mild elevations. Liver (Alpha fetoprotein – AFP)Liver cancer marker test (AFP), together with Liver Function Test, is recommended for people with known Hepatitis B infection. Pancreas (CA 19.9)Serum CA19-9 levels may be elevated in up to:a) 80% of patients with pancreatic cancerb) 54-89% of patients with stomach cancerc) 64% of patients with colorectal cancerThis test is also used to monitor patients who have recovered from pancreatic cancer. Nose (EBV)EBV is linked to the development of nasopharyngeal carcinoma (NPC), risk of which may be increased if you: have a family history of NPC are a smoker consume high quantities of salted vegetables, meat & fish high in nitrosamines Prostate (PSA) – for males onlyIn Singapore, adenocarcinoma of the prostate is the 6th most common cancer among men. Screening with PSA has the potential of early detection and treatment of organ-confined disease. Testicular (Beta HCG) – for males onlyElevated Beta HCG levels may indicate testicular cancer in men. Marker Ovarian (CA125) – for females onlyCA125 is a protein that may be elevated in cases of ovarian cancer. Breast (CA15.3) – for females onlyThe CA15.3 test is used to monitor metastatic breast cancer and early recurrence of breast cancer.