CA 19‑9, Pleural Fluid
Also known as: Cancer Antigen 19-9, Carbohydrate Antigen 19-9
Use
Carbohydrate Antigen 19‑9 (CA 19‑9) measured in pleural fluid may aid in evaluating suspected malignancy, but it is not specific and should not be used as the sole diagnostic basis; results must be interpreted alongside cytology, imaging, and clinical findings. Low or negative results (e.g. <20 U/mL) may be misleading in Lewis nonsecretor individuals or non‑CA 19‑9- secreting tumors, and CA 19‑9 may also be elevated in benign conditions such as liver cirrhosis, pancreatitis, gallstones, and cholecystitis. Interference from heterophile antibodies (HAMA) may occur and must be considered. (Source: Mayo Clinic Laboratories)
Special Instructions
Not provided.
Limitations
Not provided.
Methodology
Immunoassay (Multiplex Protein Panel)
Biomarkers
CA 19‑9
Protein
LOINC Codes
- 19163-5 - Cancer Ag19-9 Plr-aCnc
- 19163-5 - Cancer Ag19-9 Plr-aCnc
- 39111-0 - Bdy site
Result Turnaround Time
Not provided.
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
Causes for Rejection
Samples <0.5 mL may be rejected
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 7 days |
| Refrigerated | 14 days |
| Frozen | 90 days |
Other tests from different labs that may be relevant