Laboratory: Clinical Biochemistry  (SENDOUTS)
Test Name:
Test Code: PHRP
Clinical Information:
Parathyroid hormone-related peptide (PTHrP) testing is used in the assessment of patients with hypercalcemia of unknown origin and in suspected humoral hypercalcemia of malignancy.
PTHrP is produced by most tissues and is structurally similar to PTH, allowing it to bind to the same receptors. Hypercalcemia of malignancy, a common complication of cancer, is caused by elevations of PTHrP. This leads to hypercalcemia by stimulating calcium resorption from bone and reabsorbtion in the kidneys. PTHrP also plays a significant role in osteolysis in bony metastases, particularly in breast cancer.
Collection Devices:
Specimen Required:

Plasma: 1.0 mL
Pediatric Plasma: 0.7 mL

Collect blood in an ice-cooled EDTA tube and send immediately to lab on ice for processing.
Stability 30 days frozen.
Reference Values:
≤ 4.2 pmol/L
For more information:
PTHrP  - Mayo Medical Laboratories 
Within 2 Weeks
See Also:
More Information:
Spin down in a refrigerated centrifuge or in chilled centrifuge cups.  Separate and freeze within 2hr of collection.  Store and send EDTA plasma frozen in a plastic vial to Mayo Medical Laboratories (MML).  If the specimen thaws, it is unsuitable for analysis.