Flashcards in Lab Assessment of Tumor Markers Deck (17):
A 63 yo Caucasian man has a PSA of 5.2 on routine physical exam. DRE reveals a smooth enlarged prostate w/out focal nodulatrity. What do you recommend as further work up? Diagnosis?
%free PSA is 28% suggesting he has a 16-25% probability of cancer
Dx: Prostate bx
How do you explain rising PSA in patients with a UTI?
PSA peaks until UTI is treated
What pre-analytical factors affect PSA?
1. Biologic variation
- total PSA 6-30%
- free PSA 13-15%
- %fPSA 8-15%
2. Prostate manipulation
- DRE delay 1 wk
- needle bx has 5-50xincrase, wait 6 weeks
- ejaculation - abstain 24-48 hours
3. Exercise (avoid biking)
4. Prostatitis (significant increase - treat with 4-6 wks with abx)
5. Drugs (Finasteride for treatment of BPH: 50% decrease of PSA)
What is the purpose of a PCA3 assay?
aid in clinical decisions for when to re‐biopsy patients previously biopsy‐ negative for prostate cancer
Should the PCA3 assay be used?
clinical validity is INADEQUATE to inform decisions on when to REBIOPSY previously biopsy negative pts for prostate cancer or to inform initial decisions on whether to biopsy.
Does not help in determining whether it is indolent or aggressive.
A pt with known HCC who is a carrier of HBV has AFP conc which are high but stable in the 1000s. On most recent visit his AFP is 58.
What is the high dose hook (prozone) effect? How do you identify this effect?
• This is due to the excess amount of antigen biding to either capture or labeled antibody and prevent the formation of the “sandwich” complex.
• How to identify high dose hook effect ?
Assay specimens at TWO dilutions
When should you use CA125?
indicated as a ONE TIME TEST for use as an aid in the detection of RESIDUAL OVARIAN CARCINOMA in patients who have UNDERGONE FIRST LINE THERAPY and would be considered for diagnostic second‐look procedures
Interpretation: At the time of second look, surgical procedures might be deferred in patients with CA125 levels which remain in the normal range.
An assay value greater than _____ is indicative of residual disease
What causes elevation of CA125 in non-cancer conditions?
– First trimester of pregnancy
– Congestive heart failure
– Liver cirrhosis
– Uterine myofibroma
– Benign ovarian tumors
What causes elevation of CA125 in non-gyn cancers?
– Liver cancer
– Lung cancer
– Breast cancer
– Pancreatic cancer
What percent of healthy subjects have CA125 levels greater than 35U/mL?
What is HE4 used for?
monitor recurrence or progressive disease in pts with epithelial ovarian cancer
elevated less frequently than CA125 in benign disease so its BETTER
Where does HE4 come from?
normally expressed in many tissues including the female reproductive tract
What is the ROMA algorithm?
ROMATM (HE4 + CA125)
What is ROMA used for?
ROMA is used to startify woman into LIKELIHOOD groups for finding cancer on surgery
it should only be used as an ADJUNCT test
What is OVA1 algorithm?
OVA1TM: CA125 + Prealbumin + Apolipoprotein A‐1 + β2‐ microglobulin + Transferrin