Parathyroid Cancer: Diagnosis

Approved by the Cancer.Net Editorial Board, 06/2017

ON THIS PAGE: You will find a list of common tests, procedures, and scans that doctors use to find the cause of a medical problem. Use the menu to see other pages.

Doctors use many tests to find, or diagnose, a tumor. They also do tests to learn if a tumor has spread to another part of the body from where it started. If this happens, it is called metastasis. For example, imaging tests can show if the tumor has spread. Imaging tests show pictures of the inside of the body. Doctors may also do tests to learn which treatments could work best.

For most types of tumors, a biopsy is the only sure way for the doctor to know whether an area of the body has cancer. In a biopsy, the doctor takes a small sample of tissue for testing in a laboratory. If a biopsy is not possible, the doctor may suggest other tests that will help make a diagnosis.

This list describes options for diagnosing this type of tumor. Not all tests listed below will be used for every person. Your doctor may consider these factors when choosing a diagnostic test:

  • The type of tumor suspected

  • Your signs and symptoms

  • Your age and medical condition

  • The results of earlier medical tests

In addition to a physical examination, the following tests may be used to diagnose a parathyroid tumor:

  • Blood/urine tests. Many types of blood or urine tests may be done if a person has problems with their parathyroid. The most common test is a serum calcium test. Elevated serum calcium levels can suggest the presence of a parathyroid tumor or hyperplasia, which are overactive cells, on 1 or more glands. Another common laboratory test looks for elevated levels of the parathyroid hormone (PTH) and phosphorus levels in the blood. Doctors may suspect parathyroid cancer if these blood tests find a very high level of calcium and/or PTH.

  • Computed tomography (CT or CAT) scan. A CT scan creates a 2-dimensional picture of the inside of the body using x-rays taken from different angles. A computer combines these images into a detailed, cross-sectional view that shows any abnormalities or tumors. A CT scan can be used to measure the tumor’s size. Sometimes, a special dye called a contrast medium is given before the scan to provide better detail on the image. This dye can be injected into a patient’s vein or given as a pill to swallow.

  • Sestamibi/SPECT scan. SPECT is a type of CT scan (see above), and it stands for “single proton emission computerized tomography.” A sestamibi/SPECT scan is a procedure in which a specific protein, called sestamibi, is mixed with a radioactive material and injected into the patient’s vein. A parathyroid tumor will absorb the material, and the tumor will be visible on an x-ray of the neck. A sestamibi/SPECT scan may be recommended if laboratory tests show an elevated level of PTH or it may be used to evaluate parathyroid cancer that has spread to distant parts of the body or come back after treatment. See the Stages section for a full description of these stages.

  • Ultrasound. An ultrasound uses sound waves to create a picture of the internal organs. An ultrasound is very useful for locating a tumor in or around the thyroid gland. However, it has limitations if the tumor is located lower in the neck or upper chest.

  • Magnetic resonance imaging (MRI). An MRI uses magnetic fields, not x-rays, to produce detailed images of the body. MRI can be used to measure the tumor’s size. A special dye called a contrast medium is given before the scan to create a clearer picture. This dye can be injected into a patient’s vein or given as a pill to swallow.

  • Surgery. Removing the entire tumor during a surgical operation is the most common way to diagnose both benign and cancerous parathyroid tumors. The tumor is then analyzed by a pathologist. A pathologist is a doctor who specializes in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease. Parathyroid cancer is usually suspected before an operation based on a high serum calcium level, tumor size, and scans. A biopsy is generally not recommended as a separate procedure from surgery for a parathyroid tumor.

Often, test results showing a higher level of PTH or obvious symptoms of hypercalcemia are signs that cancer may be present. Imaging, such as a CT scan, can also show if cancer has developed. In some instances, a biopsy of the neck can be done, if surgery is not recommended by surgeons experienced in treating parathyroid tumors.

After diagnostic tests are done, your doctor will review all of the results with you. If the diagnosis is a cancerous parathyroid tumor, these results can also help the doctor describe the tumor. This is called staging.

The next section in this guide is Stages. It explains the system doctors use to describe the extent of the disease. You may use the menu to choose a different section to read in this guide.