Plasma pancreatic polypeptide, PP, human pancreatic polypeptide
This test measures a substance in your blood called pancreatic polypeptide. Pancreatic polypeptide is secreted by cells in your pancreas.
People who have neuroendocrine tumors have higher levels of this substance. These tumors can be functional or nonfunctional. Nonfunctional tumors are more common. They are called nonfunctional because they secrete substances that do not cause symptoms. That means they may not produce any symptoms until they have grown large.
You may need this test if your doctor suspects that you have a pancreatic neuroendocrine tumor. When these tumors cause symptoms, they can seem similar to many other common digestive problems. Symptoms of nonfunctional pancreatic neuroendocrine tumors include:
Jaundice, or yellow discoloration of the skin
If you have already been diagnosed with a pancreatic neuroendocrine tumor, you may need this test to help your doctor decide on the best treatment for you.
Your doctor may also order other tests to look for other substances in your blood that rise if you have a pancreatic neuroendocrine tumor. These substances are called biochemical tumor markers.
Your doctor may also order an imaging test that takes a picture of your pancreas. He or she may also order a biopsy, in which he or she will take a small piece of the tumor and examine it under a microscope.
Many things may affect your lab test results. These include the method each lab uses to do the test. Even if your test results are different from the normal value, you may not have a problem. To learn what the results mean for you, talk with your health care provider.
Pancreatic polypeptide is measured in picograms per milliliter (pg/mL). Normal results increase with age and range from less than 228 pg/mL in your 20s to less than 332 pg/mL in your 70s.
A high blood level may mean you have:
A pancreatic neuroendocrine tumor
Another type of endocrine pancreatic tumor
The test requires a blood sample, which is drawn through a needle from a vein in your arm.
Taking a blood sample with a needle carries risks that include bleeding, infection, bruising, or feeling dizzy. When the needle pricks your arm, you may feel a slight stinging sensation or pain. Afterward, the site may be slightly sore.
Eating before the test will cause pancreatic polypeptide levels to rise.
You will need to fast for eight hours before this test. Be sure your doctor knows about all medicines, herbs, vitamins, and supplements you are taking. This includes medicines that don't need a prescription and any illicit drugs you may use.