What Is Pilocytic Astrocytoma?

Pilocytic astrocytoma (PA) is a slow-growing central nervous system tumor that originates from star-shaped cells in the brain and spinal cord called astrocytes. It is the most common pediatric tumor. It mainly occurs in young people under the age of 19.

The most common initial symptoms are headache, nausea, and seizure. PA generally has a good prognosis. Early treatment ensures that the tumor does not invade or press on surrounding tissues and cause permanent damage. 

This article discusses the symptoms, causes, diagnosis, and treatment of PA.

Pilocytic Astrocytoma Symptoms

PA may be benign, causing few, if any, symptoms, but generally symptoms vary based on the size, location, and extent of damage by the tumor. PA symptoms include:

• Headache (particularly in the morning or made better by vomiting)
• Unexplained vomiting 
• Vision problems, such as double vision, blurry vision, or loss of vision
• Difficulty walking or balancing
• Seizures
• Weight gain or loss
• Premature puberty
• Clumsiness
• Memory issues
• Confusion
• Fatigue 
• Changes in behavior

Causes

The exact cause of juvenile pilocytic astrocytomas is unknown, but they are more commonly associated with such genetic disorders as:

• Neurofibromatosis type 1 and type 2 (cause tumors to form on nerve tissue)
• Li-Fraumeni syndrome (a rare, inherited disorder that is caused by mutations (changes) in the TP53 gene)
• Tuberous sclerosis (a rare condition, causing mainly noncancerous tumors throughout the body)
• Nevoid basal cell carcinoma syndrome (a hereditary cancer syndrome characterized by a type of skin cancer known as basal cell carcinoma)
• Turcot syndrome (a rare, inherited disorder in which abnormal growths called polyps form on the inside walls of the colon and rectum, and tumors form in the brain)
  

Diagnosis

A diagnosis of pilocytic astrocytoma begins with a review of symptoms and your or your child's medical history. Next, your healthcare provider (commonly a pediatrician or pediatric neurologist) will perform a focused physical exam, checking how well the cranial nerves and reflexes function. Next, the provider may order the following tests to confirm or rule out a pilocytic astrocytoma diagnosis:

• Imaging scans: These include computed tomography (CT) and magnetic resonance imaging (MRI) scans. Imaging scans are immensely important in helping your provider determine the size and location of your pilocytic astrocytoma. Imaging scans may also help you rule in or rule out brain cancer by showing the presence or absence of specific tumor characteristics.
• Biopsy/Surgery: A biopsy involves taking a sample of the tumor tissue so that the cells can be analyzed under a microscope. This test is used to determine whether or not a tumor is an astrocytoma.
• Electroencephalograms (EEG): An EEG looks at the brain waves, which may give your provider clues about potential tumors that may be situated in the cerebral hemispheres of the brain.
• Genetic sequencing: Genetic sequencing involves taking samples of cancerous tissue and examining its genetic makeup to determine the properties of these tumor cells.
  

Treatment

Standard treatment is surgical resection of the tumor. The goal of surgery is to remove as much of the tumor as possible. The 10-year survival rate is approximately 95% if completely resected.

For completely removed tumors, a maximum of three-year surveillance imaging is recommended due to the minimal risk of recurrence.

Prognosis 

Your individual outlook depends on a number of factors, including:

• The extent and severity of your cancer at diagnosis
• Your overall health
• The kind of treatment you receive
• How your body responds to that treatment

The 10-year survival rate is approximately 95% if completely resected.

Summary

Pilocytic astrocytoma (PA) is a slow-growing, highly curable central nervous system tumor, most commonly seen in children, that originates from star-shaped cells in the brain and spinal cord called astrocytes.

A Word From Verywell

PA is a highly curable brain tumor that mainly develops in children. The signs of PA may be subtle at first and only begin to affect your or your child's quality of life when the tumors are large in size or pressing on vital tissues. Knowing the early signs and symptoms of PA ensures that you get timely treatment. Surgery alone usually leads to the resolution of your symptoms.