α-Fetoprotein (AFP), Tumor Marker
Also known as: AFP, Serum, Alpha-Fetoprotein (AFP), Serum, Tumor Marker
Use
The most important application of AFP testing in cancer management is for testicular cancer. Although not present in pure seminoma,1 elevated serum AFP is closely associated with nonseminomatous testicular cancer.2-4 The measurement of AFP in serum, in conjunction with serum hCG, is an established regimen for monitoring patients with nonseminomatous testicular cancer.5-8 In addition, monitoring the rate of AFP clearance from serum after treatment is an indicator of the effectiveness of therapy.9,10 Conversely, the growth rate of progressive cancer can be monitored by serially measuring serum AFP concentration over time.11 Serial serum AFP testing is a useful adjunctive test for managing nonseminomatous testicular cancer.
Special Instructions
If patient is pregnant, include gestational age on the test request and order test 010801. Different assay methodologies should not be used interchangeably for serial testing. Recommended to use one assay method consistently for monitoring therapy. This test is for one-time use only; for serial monitoring, use test 480012. Patients on high-dose biotin should stop 72 hours before collection due to potential interference.
Limitations
AFP values can vary depending on the test procedure used. Different procedures' results cannot be directly compared and may lead to erroneous interpretations. Erroneous findings may occur in samples from patients treated with monoclonal mouse antibodies. Interference can occur due to high titers of antibodies to streptavidin and ruthenium, though additives minimize these effects. Results should be assessed with the patient's history and other findings. Determining AFP for general cancer screening is not recommended.
Methodology
Immunoassay (ECLIA)
Biomarkers
LOINC Codes
- 53962-7
- 53962-7
Result Turnaround Time
1 day
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.7 mL (Note: This volume does not allow for repeat testing.)
Container
Gel-barrier tube (preferred) or red-top tube
Collection Instructions
If a red-top tube is used, transfer separated serum to a plastic transport tube.
Patient Preparation
Patients should be cautioned to stop biotin consumption at least 72 hours prior to the collection of a sample.
Storage Instructions
Room temperature
Causes for Rejection
Citrate plasma specimen; improper labeling
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 14 days |
| Refrigerated | 14 days |
| Frozen | 14 days |