Tumour markers cancer Flashcards
What are the minimal requirements for a tumour marker to be used in cacner
Reliable, quick, cheap assay
High sensitivity >50% and specificity >95%
High predicitve calue of postiie and negative results
What is hCG
Glycoprotein physiologically made by syncitiotrophoblast of placenta - pregnancy
What cancers does hCG have 100% sensitivity for
Testicular
Placental choriocarcinomas and hydatiform moles
Is 50% sensitive to Non semanous germ cell, 7-14% for seminonmous germ cell tumours
Extermely accurate as to whether cancer has been treated
What is AFP
Synthesised by foetal yolk sac, liver and intestine
Albumin liek carrier protein
When is AFP elevated
Moderately - pancreatic, biliary, gastric, bronchial cancers
Non malignant hepatic disease
Increased = hepatocellular carcinoma and GCT of testses, ovary and midline structures incl mediastinum and pineal gland that contain yolk sac tissue
Can increase as result of chemo
What cancers is PLAP increased in
Isoenzyme of ALP
Elevated in seminoma nad ovarian dysgerminoma
Slight increase in smokers
What is CA19-9 and where is it mader
Epithelium of foetal stomach, intestine and pancreas
Can be elevated in mucinous tumour of ovary
What is CA19-9 used to monitor and what is it most accurate for
Monitor response to treatment in gastric and pancreatic cancer
Not usfeul in screening pancreatic cancer
Not good for how bulky tumour is, >10,000 = metastatic disease
What tumour marker rises in cholestasis
CA19-9 - exclusively exreted by bile
What is inhibin used for
Secreted by granulosa cells incl sertolic ells and inhibits pituitary FSH
Useful marker for granulosa cell tumours in ovary - over oestradiol
When is CEA raised
GI tract carcinomas
Severe benign liver disease
Inflammatory lesions esp GI
Infection
Trauma
Infarction
Collagen disease
Renal impairment
Smoking
What can be used to determine response to treatment in widespread metastatic tumours
CEA
What is CA15-3 useful for
Determining severity of disease eg staging of breast cacner
What can CA15-3 detect before other tests can
Leve during follow up can detect relapse 2-9 months before clinical signs and symptoms develop
When is CA-125 useful in ovarian cancer and less useufl
90% + IN STAGE ii/iv, 50% earlier - only helpful to diagnose late stage ovarian disease
positive 80% of time in ovarian cacner, much less in intra abdominal tumours
CA125 what most useful for
Prognostic factor
Monitor response to chemo and detection of relaspe
RMI index for pelvic mass
What indicates a good response to treatment in CA125
> 7 fold fall in CA125
What RMI requires referral to oncology
> 200
<200 surgery by gynaecologist then refer to onc
What is SCC ass antigen
Glycoprotein used for monitoring SC cervical cancer - 70-85% sensitive and head and neck SC - 60^
Also NSCLC (not routine use)
More for treatment response and relapse
What is PSA
Serine protease produced by prostate epithelium to liquefy fel surrounding spermatazoa -> fully mobile
What is an elevated PSA
> 4
what is used in screening for medullary carcinoma of thyroid
Calcitonin and calcitonin gene related peptide
What hormones can be used to detect neuroblastoma
Catecholamine metabolites
Vanillylmandelic acid
homovanillic acid
What does LDH measure
Buk of tumour
Does this as measures necrosis (intracellular enxyme) - ass with rapid growing tumours
What crisis can LDH be useful in predicting the risk of
Identifies patients at risk of tumour lysis syndrome
What tumour marker used in myeloma and NHL
Beta 2 microglobulin
What tumour marker used in myeloma
Monoclonal paraproteins
What tumour marker is used for papillary and follicular thyroid cacner
thyrodglobulin
What cancers does neurone-sepcific enolase monitor
Neuroblastoma, SCLC
How often are tumour markers checked
With each cyle of chemo to check resposne
After treatment:
3 monthly for 2 yeras
6 monthly for 3 years
Non after 5 years
