Alpha-Fetoprotein (AFP), Peritoneal Fluid
Use
The Alpha-Fetoprotein (AFP) test in peritoneal fluid is used as an adjunct to cytology to differentiate between malignancy-related ascites and benign causes of ascites formation. It provides important information in conjunction with clinical evaluation, especially in patients with a history of hepatocellular carcinoma (HCC) when the cause of peritoneal fluid accumulation is uncertain. AFP concentrations in peritoneal fluid are assessed to aid in diagnosing ascites related to malignancies like HCC, where elevated levels of AFP can be suspicious of malignancy.
Special Instructions
The test should not be ordered using peritoneal washings as they are not an approved specimen type for this assay. An electronic Oncology Test Request form (T729) should be completed if not ordering electronically. The preferred container is a plain, plastic screw-top tube with a specimen volume of 2 mL, and the minimum volume required for testing is 0.5 mL.
Limitations
Peritoneal fluid AFP concentration should not be used as absolute evidence for the presence or absence of malignant disease. Results should be interpreted alongside clinical evaluation and other diagnostic procedures. In some immunoassays, high concentrations of analyte can lead to a hook effect, resulting in inaccurate measurements. Human anti-mouse antibodies (HAMA) can also interfere with the assay.
New York Approved
Methodology
Immunoassay (Multiplex Protein Panel)
Biomarkers
LOINC Codes
- 49761-0
- 49761-0
- 39111-0
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Body Fluid
Volume
2 mL
Minimum Volume
0.5 mL
Container
Plain, plastic, screw-top tube
Collection Instructions
Sources include peritoneal, abdominal, ascites, and paracentesis (peritoneal washings are not acceptable).
Causes for Rejection
Gross hemolysis
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 7 days |
| Refrigerated | 7 days |
| Frozen | 90 days |