Children's Health

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Tests used to diagnose and stage MEN syndromes depend on the symptoms and the patient's family history. They may include:

• Physical exam and history.
• Blood chemistry studies.
• Ultrasound.
• MRI.
• CT scan.
• PET scan.
• Fine-needle aspiration (FNA) or surgical biopsy.

See the General Information section for a description of these tests and procedures.

Other tests and procedures used to diagnose MEN syndromes include the following:

• Genetic testing: A test to analyze DNA and check for a genetic alteration that may indicate an increased risk for developing a specific disease or disorder.
• Blood hormone studies: A procedure in which a blood sample is checked to measure the amounts of certain hormones released into the blood by organs and tissues in the body. An unusual (higher or lower than normal) amount of a substance can be a sign of disease in the organ or tissue that makes it. The blood may be checked for abnormal levels of thyroid-stimulating hormone (TSH). TSH is made by the pituitary gland in the brain. It stimulates the release of thyroid hormone and controls how fast follicular thyroid cells grow. The blood may also be checked for high levels of the hormone calcitonin or parathyroid hormone (PTH).
• Radioactive iodinescan (RAI scan): A procedure to find areas in the body where thyroid cancer cells may be dividing quickly. Radioactive iodine (RAI) is used because only thyroid cells take up iodine. A very small amount of RAI is swallowed, travels through the blood, and collects in thyroid tissue and thyroid cancer cells anywhere in the body. Abnormal thyroid cells take up less iodine than normal thyroid cells do. Areas that do not take up the iodine normally are called cold spots. Cold spots show up lighter in the picture made by the scan. They can be either benign (not cancer) or malignant, so a biopsy is done to find out if they are cancer.
• Sestamibi scan: A type of radionuclide scan used to find an overactive parathyroid gland. A small amount of a radioactive substance called technetium 99 is injected into a vein and travels through the bloodstream to the parathyroid gland. The radioactive substance will collect in the overactive gland and show up brightly on a special camera that detects radioactivity.
• Angiogram: A procedure to look at blood vessels and the flow of blood. A contrast dye is injected into a blood vessel. As the contrast dye moves through the blood vessel, x-rays are taken to see if there are any blockages.
• Venous sampling for an overactive parathyroid gland: A procedure in which a sample of blood is taken from veins near the parathyroid glands. The sample is checked to measure the amount of parathyroid hormone released into the blood by each gland. Venous sampling may be done if blood tests show there is an overactive parathyroid gland but imaging tests don't show which one it is.
• Somatostatin receptor scintigraphy: A type of radionuclide scan that may be used to find tumors. A small amount of radioactive octreotide (a hormone that attaches to tumors) is injected into a vein and travels through the blood. The radioactive octreotide attaches to the tumor and a special camera that detects radioactivity is used to show where the tumors are in the body. This procedure is also called octreotide scan and SRS.
• MIBG scan: A procedure used to find neuroendocrine tumors, such as pheochromocytoma. A very small amount of radioactive material called MIBG is injected into a vein and travels through the bloodstream. Pheochromocytoma cells take up the radioactive material and are detected by a device that measures radiation.
• Blood catecholamine studies: A procedure in which a blood sample is checked to measure the amount of certain catecholamines released into the blood. Substances caused by the breakdown of these catecholamines are also measured. An unusual (higher- or lower-than-normal) amount of a substance can be a sign of disease in the organ or tissue that makes it. Higher-than-normal amounts may be a sign of pheochromocytoma.
• Twenty-four-hour urine test: A test in which urine is collected for 24 hours to measure the amounts of catecholamines in the urine. Substances caused by the breakdown of these catecholamines are also measured. An unusual (higher- or lower-than-normal) amount of a substance can be a sign of disease in the organ or tissue that makes it. Higher-than-normal amounts may be a sign of pheochromocytoma.
• Pentagastrin stimulation test: A test in which blood samples are checked to measure the amount of calcitonin in the blood. Calcium gluconate and pentagastrin are injected into the blood and then several blood samples are taken over the next 5 minutes. If the level of calcitonin in the blood increases, it may be a sign of medullary thyroid cancer.