Cerebellar pilocytic astrocytoma

At the Dana-Farber/Children's Hospital Cancer Care,our team knows that you’re probably very concerned about your child’s tumor. It might ease your mind to know that this kind of cancer has a very high cure rate and that we’ve developed innovative treatments for children with low grade glioma. Learning more about this condition may help you feel more confident and informed as we work towards healing your child.

We understand you want to know more about cerebellar pilocytic astrocytoma, and will have many questions including:

• What is it?
• What can we do about it?
• How will it affect my child long-term?

We’ve provided some answers to these questions here, and when you meet with our experts, we can talk with you more about your child’s diagnosis and treatment.

What is cerebellar pilocytic astrocytoma?

A cerebellar pilocytic astrocytoma is a brain tumor arising from a type of cell found in the central nervous system known as a glial cell. These tumors originate from a specific type of glial cell called an astrocyte. Astrocytes make up the supportive network of the brain, providing structural support and several other functions. These cells are named for their star-like appearance. Cerebellar pilocytic astrocytoma grows in the rear part of the brain known as the cerebellum, which controls balance and coordination.

Cerebellar pilocytic astrocytoma is a grade I tumor, which means it often remains in a small focal area. It is different than grade 2 astrocytoma (fibrillary astrocytoma) which tend to spread out into the surrounding areas. It’s important to note that cerebellar pilocytic astrocytoma does not develop into cerebellar fibrillary astrocytoma.

How could this tumor affect my child’s mental abilities?

No. The cerebellum does not control conscious thinking or mental abilities. So pressure on the cerebellum from cerebellum astrocytoma will not affect the child’s mental abilities.

Causes

What causes cerebellar pilocytic astrocytoma?

The cause of cerebellar pilocytic astrocytoma is still under intensive study.  Achromosomal abnormality involving a gene called BRAF, is implicated in a large percentage of these tumors.

BRAF is a gene that is part of a chain of molecules that receives messages from the surrounding environment of the cell and is partly responsible for  sending messages to tell a cell to divide.

In cerebellar pilocytic astrocytoma, the molecule BRAF has an error that tells the nucleus to keep dividing. This is caused by a chromosomal abnormality. The uncontrolled division is responsible for cerebellar pilocytic astrocytoma.

Fortunately, the BRAF mutation is a local mutation. This means that it is an error only present in the tumor cells, and it is not a systemic problem affecting other cells of the body.

Symptoms

What are the symptoms of a cerebellar pilocytic astrocytoma?

Due to the relatively slow growth rate of cerebellar pilocytic astrocytoma, a child with this tumor tend to have symptoms for many months before being seen by a doctor. Some children, however, have a more sudden onset of symptoms and are related to blockage of the flow of cerebral spinal fluid. The following are the most common symptoms of a cerebellar pilocytic astrocytoma, however, each child may experience symptoms differently:

• More that 90 percent of children have increased pressure within the brain, causing:
  • headache (generally upon awakening in the morning)
  • vomiting
  • fatigue
• Most affected children have difficulty with balance and coordination.
• Many children have vision problems, such as seeing double.

The symptoms of a tumor may resemble other conditions or medical problems. Always consult your child's physician for a diagnosis.

Questions to ask your doctor

We understand that you know what’s best for your child, and that you play an important role in the care of your child. Our team will work with you to help your child through the treatment and on through recovery. By asking questions of your child’s doctor, you can help facilitate a conversation between you and your child’s care team. Sometimes, it’s helpful to write your questions down, so you can remember them for the appointment. There are several questions you can ask your child’s doctor, such as:

• How do you decide treatment recommendations?
• How long will treatment last?
• What are the possible short and long-term complications of treatment? How will they be addressed?
• How will my child’s long-term health be affected by the cancer and treatment?
• What resources are available to my child and the rest of my family?