Pleomorphic xanthoastrocytoma (PXA) is a rare, benign tumor that likely arises from astrocytes, cells in the nervous system that make up the supportive network for the brain. They typically occur in the cerebral hemispheres (the uppermost sections of the brain) and the leptomeninges, one of the layers covering the brain. They rarely develop in the spinal cord.
Patients with PXA are treated at Dana-Farber/Boston Children's Cancer and Blood Disorders Center through the Brain Tumor Center. Continue reading to learn more about PXA or visit the Brain Tumor Center homepage to learn about our expertise with this condition.
The most common symptom of PXA at diagnosis is the sudden onset of seizure activity. In fact, nearly 70 percent of children diagnosed with these tumors have seizures. Other, less common symptoms include:
- Signs of intracranial pressure, such as headache (generally upon awakening), nausea and vomiting
- Hemiparesis (weakness on one side of the body)
- Change in behavior
These tumors, which often occur in children and teenagers, appear to develop spontaneously. Very rarely do they transform into malignant tumors.
In addition to a complete physical exam, doctors diagnose PXA with:
- Diagnostic imaging
- Electroencephalogram (EEG), which records the brain’s continuous electrical activity and helps to identify and localize seizure activity to a particular section of the brain
- Biopsy
After all tests are completed, doctors will be able to outline the best treatment options.
The following treatments may be used alone or in combination to treat PXA:
- Neurosurgery to remove as much of the tumor as possible. If the tumor is completely removed, no other treatment is required other than serial MRIs to monitor for re-growth. A second surgical procedure may be performed if the tumor cannot be completely removed and increases in size, or if it comes back.
- Radiation therapy may be considered, but does not influence long-term outcomes.
- Biologic therapy
Doctors at Dana-Farber have discovered a mutation that occurs in over half of all patients with PXA and there are now new drugs that target this mutation available.
There can be side effects related to the tumor itself or its treatment. Knowing what these side effects are can help physicians prepare for and, in some cases, prevent these symptoms from occurring.
Recurrences can happen with PXAs. Radiation therapy should be considered for patients with recurrent disease whose tumor has been completely removed. If disease recurs in patients whose tumors have been incompletely removed, a second attempt at surgical removal is usually performed.
There is over a 90 percent survival rate for patients whose tumors have been completely removed. After incomplete removal, the long-term survival is still excellent although more therapy is required.