Cancer Antigen 19-9
(CA 19-9)

Sample type:

Uses:

Precautions:

Blood should be drawn using standard venipuncture techniques and the serum should be separated from the red blood cells as soon as practical. Avoid grossly hemolytic, lipemic or turbid samples.
Plasma samples collected in tubes containing EDTA, heparin, or oxalate may interfere with test procedures and should be avoided.
Specimens should be capped and may be stored up to 48 hours at 2-8°C, prior to assaying. Specimens held for a longer time can be frozen at -20°C. Thawed samples must be mixed prior to testing.
The wash procedure is critical. Insufficient washing will result in poor precision and falsely elevated absorbance readings.

Interfering Factors:

Patients known to be genotypically negative for Lewis blood group antigens will be unable to produce the CA 19-9 antigen even in the presence of malignant tissue.

Pre analytical errors:

1) Wrong Labeling of the Containers.

2) Errors in Specimen Preparation.

3) Inappropriate Laboratory Test Requisition.

4) Inadequate Volume.

Corrective action:

1) Make correct Labeling of the Containers.

2) No errors in Specimen Preparation.

3) Appropriate Laboratory Test Requisition.

4) Adequate Volume.

Post analytical errors:

1) Failure in reporting.Erroneous

2) Validation of analytical data.

3) Improper data entry.

Corrective action:

1) Write correct report.

2) All analytical data should be valid

3) Proper data entery.

Reference range:

The normal range of CA 19-9 is between 0 and 37 U/mL (units/milliliter).