Mayo Clinic doctors use the latest diagnostic tests to help determine the best treatment plan for you. In tests that involve radiation, specialists carefully monitor doses to avoid the risk of radiation overexposure. Tests to diagnose islet cell tumors may include:
- Ultrasound. Ultrasound is an imaging method that uses high-frequency sound waves to form images on a screen to identify tumors in the pancreas and other organs.
- Endoscopic ultrasound (EUS). For more-detailed images, an ultrasound probe is passed through a flexible tube (endoscope) into your stomach. Sound waves are directed toward the pancreas, and a computer translates them into images, which identify small tumors and help determine the disease stage.
- Computerized tomography (CT) scans. CT scans generate 2-D or 3-D images that may reveal whether cancer has invaded other tissues or organs.
- Magnetic resonance imaging (MRI). An MRI creates detailed images of the pancreas and can identify small abnormalities seen in 2-D and 3-D views.
- Somatostatin receptor scintigraphy (SRS). This procedure, also called Octreoscan, uses imaging combined with a radioactive hormone that is injected into a vein to locate tumors throughout the body.
- Positron emission tomography (PET). To perform a PET scan, doctors inject a radioactive type of sugar (glucose) into your bloodstream. The scan helps show if a tumor has spread, because tumors typically pick up the sugar and appear on the image as "hot spots."
- Biopsy. In a biopsy, a pathologist removes a small tissue sample and looks at it under a microscope for cancer cells.
- Laparoscopy. If tissue can't be easily obtained by a biopsy, your doctor may use laparoscopy. After guiding a tiny camera into the abdomen, the doctor can determine whether the tumor has spread outside the pancreas and can also remove a tissue sample.
Read more about ultrasound, CT scan, PET scan, MRI and biopsy on MayoClinic.com.