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PTD - 206

Test Directory -  Chromogranin A/B

Clinical Indications

Chromogranin A is produced by a variety of normal and malignant neuroendocrine and sympathetic neuronal cells and may serve as a clinically useful marker for hormone-negative endocrine neoplasia.
Elevated levels of Chromogranin A are seen in neuroendocrine tumours, including phaeochromocytoma, medullary carcinoma of thyroid, pancreatic islet cell adenoma, carcinoid tumour, anterior pituitary adenoma, carotid body tumour, small cell carcinoma of the lung and neuroblastoma. 

Minor increases are seen in essential hypertension. Chromogranin A concentrations rise markedly in patients with renal failure. Chromogranin B  measurements complement Chromogranin A and are useful in evaluation of falsely elevated levels of Chromogranin A which may be found in patients with decreased renal function and treatment with proton pump inhibitors.

Request Form

Combined Pathology Blood form (Yellow/Black)

Availability

Analysed by Clinical Biochemistry, Charing Cross Hospital if specific criteria met.

Specific Criteria

Investigation of suspected neuroendocrine tumour, if specifically requested by a Consultant. 

Turnaround Time

3 weeks

Specimen

Large purple top (EDTA) tube
Samples must be transported to laboratory immediately.
Yellow top (SST) tubes should not be used.

Volume

2 ml

Causes for Rejection

Not meeting specific criteria for analysis.

Reference Range

Chromogranin A: Less than 60 pmol/L
Chromogranin B: Less than 150
pmol/L

Lab. Handling

Processing: Centrifuge and aliquot within 15 minutes of venepuncture into 2 tubes and freeze at    -20C in separating freezer (CB40), active frozen rack 110.
Referral: CGA and send or NOCGA and save in separating freezer (CB40), at -20C in the saved frozen rack.

     

Version 1.1 / August  2015                                                                                                     Approved by: Consultant Biochemist