The most common symptom of schwannomatosis is usually chronic pain – which can occur in any part of the body – caused by tumors called schwannomas pressing on nerves. Although neurological symptoms can also occur, many people with schwannomatosis experience pain as the only symptom for several years before the source of the pain is identified. For this reason, the condition is often difficult to diagnose.

People with schwannomatosis may also experience neurological and other symptoms including:

• Numbness or tingling
• Weakness, including facial weakness
• Bowel dysfunction or difficulty urinating
• Vision changes
• Headaches

Clinical Features

The main clinical feature of schwannomatosis is the development of schwannomas, tumors that grow on nerves. These tumors develop from Schwann cells, which support and protect nerve cells and serve as insulation needed to conduct information. While schwannomas are the same type of tumors that develop in people with NF2, schwannomatosis lacks many of the clinical features common in people with NF2. An important distinction is that individuals with schwannomatosis don’t develop tumors on the acoustic nerve that cause hearing loss in people with NF2. Also, other types of tumors that can occur in people with NF2 (including meningiomas, ependymomas, and astrocytomas) don’t occur in those with schwannomatosis, with rare exceptions. Features of NF1, such as learning problems and café-au-lait spots, are also not present in people with schwannomatosis. The condition also doesn't produce the visible skin tumors that occur in people with NF1 and some individuals with NF2.