What Are Malignant Peripheral Nerve Sheath Tumors?
Malignant peripheral nerve sheath tumors, also known as neurofibrosarcomas, are found in the protective lining, or myelin sheath, surrounding the peripheral (outside) nerves of the spinal cord — the nerves that reach out to the rest of the body. These rare cancerous tumors occur most commonly in the muscle, fat, nerves, and other soft tissue of the torso, arms, or legs.
What Are the Causes of Malignant Peripheral Nerve Sheath Tumors?
The exact causes of these tumors aren’t known, but they begin when a cell in the sheath develops a DNA mutation. They grow and divide much faster than normal. The excess of cells forms invasive, spreadable tumors.
Malignant peripheral nerve sheath tumors are most common in young adults and middle-aged adults, and more than half are found in people who have neurofibromatosis 1 (a non-cancerous condition that causes bone deformities).
Symptoms of Malignant Peripheral Nerve Sheath Tumors
In the early stages, malignant peripheral nerve sheath tumors may not have many symptoms. As a tumor grows and presses on the nerves, symptoms may include:
- Pain
- Weakness
- A growing lump or mass under the skin
Diagnosis and Testing
Diagnosing malignant peripheral nerve sheath tumors may include:
- Physical and neurological exams
- Imaging
- Biopsy
These same tests may be done to assess whether cancer has spread.
Treatment of Malignant Peripheral Nerve Sheath Tumors
These tumors are first attacked with surgery to remove them if possible, then with a combination of chemotherapy and radiation.
