L19 Tumor markers and Tutorial Flashcards
List characteristics of an ideal tumor marker. (5)
- High sensitivity and high specificity
- Organ-specific
- Discriminatory to identify tumor from benign states
- Correlate with mass, stage, prognosis
- Short half-life
Which of the following is incorrect?
A. PSA can be used for population-based screeening for CA prostate
B. AFP is good for screening for high risk groups e.g. Hep B carreirs for HCC
C. CA 125 can aid diagnosis of CA ovaries
D. Serial CEA can be used for diagnosis of CRC
E. In CA breast, ER/PR in anti-estrogen therapy and HER2 in transtuzumab can be used for prediction of treatment response
D
- Serial CEA is for monitoring of treatment response and detection of recurrence/relapse
The normal range of AFP?
Any circumstances with elevated AFP in healthy individuals?
Normal range: <10 mcg/L
CA if > 1000
Pregnancy! <500 mcg/L
Newborn! >10000 mcg/L > normalized in 1 year
Clinical use of AFP (when is AFP elevated)?
Benign: acute or chronic hepatitis, cirrhosis
Malignant: HCC, hepatoblastoma, NSGCT (non-seminomatous germ cell tumor) (together with HCG, LDH)
Where can CEA be found? (Carcinoembryonic antigen)
GI tract, breast, head and neck, lung
What is the normal range of CEA?
It is for the screening of CRC - T/F?
Normal < 3mcg/L (non-smoker); <5 mcg/L (smoker)
Benign conditions rarely >10 mcg/L
NOT for screening CRC
What is the clinical use of CEA (when is CEA elevated)?
Benign : IBD, cirrhosis
Malignancy: CRC, CA stomach, lung (not elevated in some CA lung!)
Clinical uses of HCG (human chorionic gonadotrophin)? (3)
- Early pregnancy: urine HCG
- Trophoblastic disease: Hydatidiform moles
- Germ cell tumor (e.g. choriocarcinoma) > placenta
Which of the following about HCG is incorrect?
A. It may be interfered by analytic interferences like heterophile Ab
B. The half life of HCG is around 5-7 days
C. Non-pregnant women (premenopause): <1 IU/L
D. Post-menopausal women: <7 IU/L
E. Men: < 2 IU/L
B
- t1/2: should be 36-48 hours
Clinical use for PSA (when will PSA be elevated)? (9)
Malignant
- CA prostate
Non-malignant
- BPH
- Prostatitis
- UTI
- urinary obstruction
Preanalytical factors
- Urological manipulation: TURP (Transurethral resection of the prostate)
- DR examination
- Prostate massage
- Ejaculation
- Invasive procedures (prostate biopsy, cystoscopy, transrectal USG, etc.)
Which of the following about PSA is correct?
A. Normal value is <4 ug/L
B. there is an age-specific range
C. Protstate health index (PHI) can improve the diagnostic performance of PSA
D. PPV (positive predicted value) of traditional PSA cutoff >4 ug/L is only 30%, meaning that only 30% of +ve cases are true +ve (elevated PSA).
E. % free pSA, p2PSA, PSA velocity and denisity can improve the diagnostic performance of PSA
All of the above
Clinical use of Cancer Antigen 125 (CA 125)?
- Epithelial ovarian Ca
- Primary Peritoneal CA
- Benign: endometriosis, pleural effusion
How CA 125 is measured to lower any analytical interference?
It can be used to assess adnexal mass (lump around uterus) together with other markers and USG such as?
Test is done during 1st half of menstrual cycle (CA 125 increases during menses)
Other markers: ROMA, RMI
Canter antigen 15-3 clinical use? (2)
How many times the cutoff represents metastasis?
- CA breast, lung, GIT, liver
- Benign: breast, liver disease
5x
Thyroglobulin clinical use? (2)
- It is considered together with [anti-Tg]
- Stimulated Tg or suppressed
- CA thyroid
- Thyrotoxicosis factitia (caused by exogenous TH)