Pheochromocytoma and Paraganglioma in Children

Pheochromocytoma and paraganglioma are rare tumors that come from the same type of nerve tissue.

Pheochromocytoma forms in the adrenal glands. There are two adrenal glands, one on top of each kidney in the back of the upper abdomen. Each adrenal gland has two parts. The outer layer of the adrenal gland is the adrenal cortex. The center of the adrenal gland is the adrenal medulla. Pheochromocytoma is a tumor of the adrenal medulla. The adrenal glands make important hormones called catecholamines. Adrenaline (epinephrine) and noradrenaline (norepinephrine) are two types of catecholamines that help control heart rate, blood pressure, blood sugar, and the way the body reacts to stress. Some pheochromocytomas release extra adrenaline and noradrenaline into the blood and cause symptoms.

Paraganglioma forms outside the adrenal glands near the carotid artery, along nerve pathways in the head and neck, and in other parts of the body. Some paragangliomas make extra catecholamines called adrenaline and noradrenaline. The release of extra adrenaline and noradrenaline into the blood may cause symptoms.

Some tumors do not make extra adrenaline or noradrenaline and do not cause symptoms. These tumors may be found when a lump forms in the neck or when a test or procedure is done for another reason. Signs and symptoms of pheochromocytoma and paraganglioma occur when too much adrenaline or noradrenaline is released into the blood. These and other symptoms may be caused by pheochromocytoma, paraganglioma, or other conditions. Check with your child’s doctor if your child has any of the following:

• High blood pressure.
• Headache.
• Heavy sweating for no known reason.
• A strong, fast, or irregular heartbeat.
• Feeling shaky.
• Being extremely pale.
• Dizziness.
• Being irritable or nervous.

These signs and symptoms may come and go but high blood pressure is more likely to occur for long periods of time in young patients. These signs and symptoms may also occur with physical activity, injury, anesthesia, surgery to remove the tumor, eating foods such as chocolate and cheese, or while passing urine (if the tumor is in the bladder).

Anything that increases your chance of getting a disease is called a risk factor. Having a risk factor doesn't mean that you will get cancer; not having risk factors doesn’t mean that you will not get cancer. Talk with your child’s doctor if you think your child may be at risk.

The risk of pheochromocytoma or paraganglioma is increased by having any of the following inherited syndromes or gene changes:

• Multiple endocrine neoplasia type 1 (MEN1) syndrome.
• Multiple endocrine neoplasia type 2 syndrome (MEN2A and MEN2B).
• von Hippel-Lindau disease (VHL).
• Neurofibromatosis type 1 (NF1).
• Carney-Stratakis dyad (paraganglioma and gastrointestinal stromal tumor [GIST]).
• Carney triad (paraganglioma, GIST, and pulmonary chondroma).

Changes in certain genes including the VHL, NF1, RET, SDHD, SDHB, SDHA, MAX, and TMEM127 genes. More than half of the children and adolescents diagnosed with pheochromocytoma or paraganglioma have an inherited syndrome or gene change that increased the risk of cancer. Genetic counseling (a discussion with a trained professional about inherited diseases) and testing is an important part of the treatment plan.

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

• Physical exam and history.
• PET scan.
• CT scan (CAT scan).
• MRI (magnetic resonance imaging).

Other tests and procedures used to diagnose pheochromocytoma and paraganglioma include the following:

Plasma-free metanephrines test: A blood test that measures the amount of metanephrines in the blood. Metanephrines are substances that are made when the body breaks down adrenaline or noradrenaline. Pheochromocytomas and paragangliomas can make large amounts of adrenaline and noradrenaline and cause high levels of metanephrines in both the blood and urine.

Blood catecholamine studies: A procedure in which a blood sample is checked to measure the amount of certain catecholamines (adrenaline or noradrenaline) 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 or paraganglioma.

Twenty-four-hour urine test: A test in which urine is collected for 24 hours to measure the amounts of catecholamines (adrenaline or noradrenaline) or metanephrines 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 or paraganglioma.

MIBG scan: A procedure used to find neuroendocrine tumors, such as pheochromocytoma and paraganglioma. A very small amount of a substance called radioactive MIBG is injected into a vein and travels through the bloodstream. Neuroendocrine tumor cells take up the radioactive MIBG and are detected by a scanner. Scans may be taken over 1-3 days. An iodine solution may be given before or during the test to keep the thyroid gland from absorbing too much of the MIBG.

Somatostatin receptor scintigraphy: A type of radionuclide scan that may be used to find tumors. A very 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.

Treatment of pheochromocytoma and paraganglioma in children may include the following:

• Surgery to completely remove the tumor.
• Combination chemotherapy, high-dose 131I-MIBG, and targeted therapy for tumors that have spread.

Before surgery, drug therapy with alpha-blockers to control blood pressure and beta-blockers to control heart rate are given. If both adrenal glands are removed, life-long hormone therapy to replace hormones made by the adrenal glands is needed after surgery.

Treatment of recurrent pheochromocytoma and paraganglioma in children may include the following:

• A clinical trial that checks a sample of the patient's tumor for certain gene changes. The type of targeted therapy that will be given to the patient depends on the type of gene change.