Tumour Markers Flashcards
What is sensitivity?
Ability to detect those with disease
What is specificity?
Ability to detect those without disease
What are the classes of tumour markers?
Cell-surface glycoproteins Oncofetal proteins Hormones Enzymes Immunoglobulins Nucleic acids
What are the cell surface glycoproteins?
Carcino-embryonic antigen (CEA)
CA125
CA19.9
What are the oncofetal proteins?
hCG
A-feto-protein (aFP)
What enzymes are tumour markers?
Acid phosphatase Alkaline phosphatase Lactate dehydrogenase Neurone specific enolase Intermediate metabolites 5-hydroxyindoleacetic acid Vanillyl mandelic acid
What hormones are tumour markers?
Thyroglobulin,
Antidiuretic hormone,
Adrenocorticotrophic hormone
What immunoglobulins are tumour markers?
Bence Jones Protein
Light Chains
How are nucleic acids used as tumour markers?
RNA + DNA detected Tumour specific (eg Philadelphia chromosome) or tissue specific (eg detection of tyrosinase expression in blood)
When can tumour markers be used for screening?
In high risk groups eg use of aFP to detect hepatocellular carcinoma in pts with hepatitis
What conditions cause a raise in CEA?
Colorectal!!
Pancreatic, gastric, breast, lung cancer
Smoking, IBS, hepatitis, pancreatitis, gastritis
When is CA125 raised?
Endometriosis, pregnancy, menstruation + ovarian cancer
What tumour markers are diagnostic in young males with widespread mets?
Serum LDH, aFP, BhCG
To diagnose chemo sensitive germ cell tumours
What does an aFP level >500 indicate?
Hepatocellular carcinoma or germ cell tumours (non-seminomatous testicular cancer)
How can you measure prognosis in testicular cancer?
Concentrations of hCG or aFP
How can you monitor response to chemo for germ cell tumours?
Concentrations of hCG + aFP
What is aFP?
Glycoprotein produced in normal fetal yolk sac, liver + intestines
Undetectable in normal individuals after 1 y/o
When is aFP raised?
Hepatitis, hepatocellular carcinoma, cancers containing yolk sacs (teratomas)
High levels = poor prognosis
When are immunoglobulins used as tumour markers?
Measure of paraproteinaemias (myeloma + Waldenstrom’s macroglobulinaemia)
Non-Hodgkins Lymphoma
Where is the Bence Jones protein found + what does it indicate?
Measured in urine
Occurs in myeloma
What cancers are CA19.9 + CA15.3 linked to?
- 9 = pancreatic
15. 3 = breast
What tumours cause a raise in Bombesin?
SCLC
Gastric
Neuroblastoma
