Chromogranin A

Additional Information:

UFHPL Epic order code: LAB2212

CPT Code(s):


Specimen Requirements:

Important: No radioisotopes should be administered to the patient within 48 hours prior to venipuncture.
Special Instructions: Values obtained with different assay methods should not be used interchangeably in serial testing. It is recommended that only one assay method be used consistently to monitor each patient’s course of therapy.

Type: Serum or plasma

Container/Tube: Lavender-top tube (EDTA), green-top tube (heparin), red-top tube or gel-barrier tube
  • Separate plasma or serum from cells immediately to avoid a false elevation of homocysteine. After one hour at room temperature, a 10 percent increase may be seen. Transfer plasma and serum to a plastic transport tube. Homocysteine results increase by approximately 35 and 75 percent for samples not centrifuged and/or not separated from the clot for periods of four and 24 hours, respectively. Serum values are expected to be higher than plasma values. Slightly higher values are observed in nonfasting patients.

Sample Volume: 2 mL

Minimum Volume: 1 mL (Repeat testing is not possible with this specimen volume.)

Storage: Refrigerate specimens after collection; samples are stable for up to 10 days refrigerated.

Stability (collection to time of analysis/testing):

  • Refrigerated: 10 days
Rejection Criteria:

  • Non-EDTA or nonheparinized plasma received
  • Frozen red-top tube received
  • Radioactive isotopes administered within 48 hours prior to venipuncture
  • Grossly hemolyzed specimen


This test is used to detect neuroendocrine cancers.


Chromogranin A levels canR be elevated in patients with severe renal failure.1 Elevated levels of CgA are also common in patients on treatment with proton pump inhibitors.2

This procedure may be considered by Medicare and other carriers as investigational and, therefore, may not be payable as a covered benefit for patients.

Results for this test are designated to be for research purposes only by the manufacturer. The performance characteristics of this product have not been established. Results for this test should not be used as absolute evidence of presence or absence of malignant disease without confirmation of the diagnosis by another medically established diagnostic product or procedure. Values obtained with different assay methods or kits cannot be used interchangeably.


Radioimmunoassay (RIA)

Reference Values:

0 – 5 nmol/L