Pancreastatin

Test Code

10498

CPT Codes
83520<br>This test is not available for New York patient testing

Preferred Specimen

2 mL serum collected in a serum separator tube (SST)

Patient Preparation
Patients must be fasting 10-12 hours prior to collection of specimens. Patient should not be on any medications that may influence Insulin levels, if possible, for at least 48 hours prior to collection.

Minimum Volume

1 mL

Instructions

Use a serum separator tube and allow samples to clot for 2 hours at room temperature or overnight at 4° C before centrifugation for 15 minutes at approximately 1000xg and freeze immediately. Collect the supernatant for assaying.

Transport Temperature

Frozen

Specimen Stability

Room temperature: Unacceptable
Refrigerated: Unacceptable
Frozen: 6 months

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Specimens received unfrozen • Specimens received at refrigerated temperatures • Specimens outside of listed stability

Methodology
Enzyme Immunoassay (EIA)

FDA Status
The performance characteristics of the listed assay was validated by BioAgilytix Diagnostics. The US FDA has not approved or cleared this test. The results of this assay can be used for clinical diagnosis without FDA approval. BioAgilytix Diagnostics is a CLIA certified, CAP accredited laboratory for performing high complexity assays such as this one.

Setup Schedule

Set up: Varies; Report available: 7 business days

Report Available

7 Days

Reference Range

0.0-246.0 pg/mL

Clinical Significance

Pancreastatin (PST), also called chromogranin A amide, is a 49-amino acid peptide that was first isolated from porcine pancreas. Pancreastatin is one of a number of biologically active peptides produced by proteolysis of the precursor molecule chromogranin A (CGA). It was first described as an inhibitor of insulin secretion, but since then many different effects have been reported. Pancreastatin is functional in humans in vivo, affecting both carbohydrate and lipid metabolism. Indeed, its actions are potent and specific. Pancreastatin is cleaved from CHGA in hormone storage granules in vivo, and its plasma concentration varies in human disease. The pancreastatin region of CHGA gives rise to three naturally occurring human variants, one of which (Gly297Ser) occurs in the functionally important carboxyl terminus of the peptide and substantially increases the peptide s potency to inhibit cellular glucose uptake. These observations establish a role for pancreastatin in human intermediary metabolism and disease and suggest that qualitative hereditary alterations in pancreastatin's primary structure may give rise to individual differences in glucose disposition. Historically analysis of pancreastatin levels has been utilized as a biomarker to establish diagnosis, and in prediction of disease recurrence, potential outcome, and efficacy of therapy in neuroendocrine tumors (NETs). However, there is growing literature on the limitations of use of monoanalytes, such as PST & Chromogranin A, for NET assessment, although conversely Chromogranin A and derived peptides are still perceived as most valuable markers of NETs. Concurrently there is increasing body of evidence on the importance of bioactive peptide fragments of Chromogranin A, including PST, in a spectrum of regulatory activities, important to maintaining homeostasis, involving the endocrine, immune, and cardiovascular systems. Hence the use of PST testing, and knowledge on the clinical implications is actively evolving towards a broader testing population.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.