Pediatric Schwannomatosis

Schwannomatosis is a very rare form of neurofibromatosis that has only recently been recognized and appears to affect about 1 in 40,000 individuals. It is less well understood than NF1 and NF2, and features may vary greatly between patients.

Neurofibromatosis Type 1 (NF1) is a life-long condition usually diagnosed early in life, often within the first year. NF1 is diagnosed based on specific skin, ocular and other physical findings, and genetic blood testing in selected cases. Half of all children who have NF1 inherited the disease from an affected parent, while the other half has no family history, meaning that the disease occurs spontaneously. 

Neurofibromatosis Type 2 (NF2) is less common and is also an autosomal dominant disorder. NF2 is a genetic condition that causes noncancerous growths on nerves that send balance and sound impulses from the inner ear to the brain. It affects about 1 in 25,000 babies in the U.S. The gene change that causes NF2 is on chromosome 22.

The distinguishing feature of schwannomatosis is the development of multiple schwannomas, tumors of the peripheral nervous system that arise in the nerve sheath and that are composed of Schwann cells.

The healthcare provider will ask about your child’s symptoms, health history and developmental milestones. They may also ask about your family’s health history and they will give your child a physical exam. Your child may also have tests, such as:

• Genetic tests. These are blood tests. They check for health conditions that tend to run in families.
• MRI. This test uses large magnets, radio waves, and a computer to make images of the inside of the body.
• CT scan. This test uses a series of X-rays and a computer to create images of the inside of the body. A CT scan shows more detail than a regular X-ray.
• Electroencephalogram (EEG). This test records the brain's electrical activity through sticky pads (electrodes) attached to the scalp.
• Eye exam. This is done to check for growths on the retina, cataract, or excess pressure in the eye.
• Biopsy. A small sample of tissue from a tumor or skin lesion may be taken. This is checked with a microscope.

About one-third of patients with schwannomatosis have tumors only on a single part of the body, such as an arm, a leg or a segment of the spine. The number of schwannomas on a patient can vary widely.

There is no currently accepted medical treatment or drug for schwannomatosis, but surgical management is often effective. When tumors are completely removed, pain usually subsides, although it may recur if new tumors form. When surgery is not possible, ongoing monitoring and management of pain in a multidisciplinary pain clinic is advisable.

Schwannomatosis is a lifelong condition that has no cure. Your child’s healthcare providers will work to prevent deformities or keep them to a minimum. They will also work to help your child make the most of his or her abilities. You can help your child strengthen his or her self-esteem and be as independent as possible. Physical and occupational rehabilitation, plus extra support in school, can help a child function as well as possible.