- Tumor Marker is a biological substance synthesized and released by cancer cells and found in an increased amount in blood, other body cells when there is a presence of cancer.
- These are the abnormally produced molecules of tumor cells such as surface antigens, cytoplasmic proteins, enzymes and hormones.
- Tumor markers can be measured in serum (or plasma).
- Tumor markers support the diagnosis of cancers, besides being useful for monitoring the response to therapy and for the early detection of recurrence
- Oncofetal Oncogenes:-
- Produced during fetal life
- Present in serum of fetus
- Decreases or disappears after birth
- Reappears in cancer patients because of reactivation of certain genes like:-
- AFP(alpha-fetoprotein) : Hepatocellular cancer, Germ Cell cancer
- CEA(Carcinoembryonic antigen)- Colorectal, GI, Pancreatic, lung cancer
- Hormonal Markers:-
- Calcitonin-Thyroid Cancer
- Growth Hormone and Prolactin- Pituitary adenoma, renal and lung cancer
- Parathyroid hormone – liver, renal, breast and lung cancer
- HCG – Teratoma of testes, choriocarcinoma.
- Carbohydrate markers:-
- High molecular weight glycoproteins
- Usually abbreviated as CA for Carbohydrate Antigen
- CA 125 – Ovarian and Endometrial cancer
- CA 549 – Breast and Ovarian Cancer
- Proteins Markers:-
- Beta Microglobulin- Multiple myeloma, B-Cell lymphoma
- C-Peptide: Insulinoma
- Ferritin: Leukemia, Liver lung and breast cancer
- Immunoglobulin/Bence Jones Protein: Multiple Myeloma
- PSA-Prostate Specific Antigen: Prostate cancer.
- Enzymes Marker:-
- Amylase: Pancreatic cancer
- Alkaline Phosphatase: Leukemia, Sarcoma, Bone and Liver Cancer
- Lactate dH: Lymphomas, Leukemia, Liver Cancer.
- Clinical Significance:-
- Differential diagnosis in symptomatic individuals
- Clinical staging of Cancer
- Prognosis of disease
- Evaluation of success of treatment
- Detection of recurrence of Cancer
- Monitoring of response to therapy