Astrocytoma

Astrocytoma is a type of tumour that can develop in the brain and spinal cord. It starts in the astrocytes of the central nervous system (CNS). Astrocytes are a type of glial cell, which is why astrocytoma may also be called a type of glioma. Astrocytomas are found in the cerebellum, cerebrum, central areas of the brain, brain stem and spinal cord.

Astrocytomas can be classified as low or high grade, depending on how the tumour cells look and how quickly they grow and spread.

Low grade means that the tumour cells are growing slowly. Low-grade astrocytomas have cells that look similar to normal cells in the brain and spinal cord (called the CNS). Most low-grade tumours are grade 1 or non-infiltrating (which means they haven't grown into surrounding tissues). Some low-grade tumours are grade 2 (called diffuse astrocytoma or fibrillary astrocytoma).

• Grade 1 tumours are considered to be benign (non-cancerous) because they grow slowly and do not grow into nearby tissue. These include pilocytic astrocytoma that occur in the cerebellum and subependymal giant cell astrocytomas (SEGAs) that occur in ventricles and are often associated with tuberous sclerosis.
• Grade 2 tumours grow slowly but can grow into nearby tissue. They have the potential to turn into grade 3 tumours.

High grade means that the tumour cells are growing rapidly. The most common grade 3 tumour is anaplastic astrocytoma. The most common grade 4 tumour is glioblastoma (also called glioblastoma multiforme, or GBM).

The healthcare team will suggest treatments based on your child's needs and work with you to develop a treatment plan. Treatment for astrocytoma depends on:

• the grade of the tumour
• the location of the tumour
• how far the tumour has grown or spread
• if the tumour can be surgically removed (is resectable)
• your child's age, neurological condition and general health

Low-grade astrocytomas are generally treated with surgery, chemotherapy, radiation therapy, targeted therapy or a combination of these treatments. If the tumour is completely removed with surgery, no other treatments may be needed. If the tumour is not completely removed, other treatments may be offered such as active surveillance, chemotherapy, radiation therapy or targeted therapy. Children with neurofibromatosis type 1 (NF1) or small tumours that are found accidentally may be treated with active surveillance.

High-grade astrocytomas are generally treated with surgery to remove as much of the tumour as possible. Even if the tumour is completely removed, chemotherapy and radiation therapy are used after surgery to reduce the risk of the brain tumour coming back. In some cases, targeted therapy may also be used.

Recurrent astrocytomas have come back after treatment. Treatment of recurrent astrocytomas depends on where the tumour is, what treatments were used previously and the grade.

• Recurrent low-grade astrocytomas are treated with surgery, radiation therapy, chemotherapy or targeted therapy. These treatments may be given alone or in combination.
• Recurrent high-grade astrocytomas are treated with surgery, chemotherapy or targeted therapy. Radiation therapy can sometimes be used again. Doctors may suggest that the child enrol in a clinical trial.

Surgery is the main treatment for astrocytomas that can be easily removed. The goal is to remove as much of the tumour as possible without damaging the surrounding healthy tissue. In general, astrocytomas in the cerebellum and cerebrum can be easily removed. Astrocytomas involving the optic nerves, hypothalamus, thalamus, brain stem and spine can be harder to remove.

If the tumour is in a place where it can't be removed with surgery, the doctor will try to get a biopsy of the tumour to find out its type and grade. Surgery may also be used to drain fluid buildup from the brain.

If the doctor can remove all of a low-grade tumour, no further treatment may be needed. If the tumour can’t be completely removed, other treatments can be used, such as radiation therapy or chemotherapy.

For high-grade tumours, surgery is usually followed by radiation therapy, with or without chemotherapy.

Find out more about surgery for childhood brain and spinal cord tumours.

Active surveillance involves watching the tumour with regular tests and exams to check if it is growing or causing symptoms. Active surveillance may be used for some low-grade astrocytomas. It may be an option for children with neurofibromatosis type 1 (NF1) or for small tumours that are found accidentally and aren't causing any symptoms.

Sometimes, a low-grade tumour can’t be completely removed with surgery. In these cases, active surveillance may be a treatment option. The child will be watched closely after surgery for any additional tumour growth. If the tumour starts growing again, more treatment will be needed. Unlike other brain tumours, low-grade astrocytomas that aren't completely removed with surgery may not regrow or cause symptoms for a long time.

Find out more about active surveillance for childhood brain and spinal cord tumours.

Radiation therapy uses high-energy rays or particles to destroy cancer cells. Radiation therapy is usually not given to children younger than 3 of age because it can damage developing brain cells. In these cases, doctors will try to delay giving radiation until the child is older. Sometimes, chemotherapy may be given first to delay radiation. Radiation therapy is also generally not used to treat children with neurofibromatosis type 1 (NF1) because their tumours respond better to other treatments.

Radiation therapy may be used:

• after surgery for tumours that were partially removed
• as a main treatment for tumours that are hard to remove with surgery (those in the brain stem, near the optic nerves, in the hypothalamus or thalamus)
• as an adjuvant therapy after surgery to prevent tumours from coming back

Radiation therapy may be used along with chemotherapy.

Find out more about radiation therapy for childhood brain and spinal cord tumours.

Chemotherapy uses drugs to destroy cancer cells. Different drugs and drug combinations are used to treat low-grade and high-grade astrocytomas.

For low-grade tumours, chemotherapy may be used when radiation therapy has to be delayed. Chemotherapy is given at regular intervals (every week to every 3 weeks) depending on the drugs that are used. Because low-grade tumours grow slowly, it takes chemotherapy longer to work. Chemotherapy may also be used after surgery if the tumour was not removed completely.

The most common chemotherapy drugs and drug combinations used to treat low-grade astrocytomas are:

• vinblastine
• carboplatin, with or without vincristine
• thioguanine (Lanvis), procarbazine (Matulane), lomustine (CeeNU, CCNU) and vincristine

Chemotherapy drugs used to treat recurrent low-grade astrocytomas include:

• vinblastine
• carboplatin and vincristine
• thioguanine, procarbazine, lomustine and vincristine
• temozolomide
• temozolomide, carboplatin and vincristine
• bevacizumab (Avastin and biosimilars) and vinblastine

For high-grade tumours, chemotherapy may be given along with radiation therapy to make radiation therapy more effective. Children younger than 3 years of age may be treated with chemotherapy to delay giving radiation therapy until they are older.

The most common chemotherapy drug used to treat high-grade astrocytoma is temozolomide. It is given during radiation therapy. After that treatment is complete, maintenance therapy with temozolomide and lomustine is given.

Other drugs that may be used to treat high-grade astrocytomas are:

• carmustine (BiCNU, BCNU)
• cisplatin
• procarbazine
• vincristine

Find out more about chemotherapy for childhood brain and spinal cord tumours.

Targeted therapy uses drugs to target specific molecules (such as proteins) on cancer cells or inside them to stop the growth and spread of cancer. Targeted therapy is sometimes used to treat astrocytomas.

Everolimus (Affinitor) and sirolimus (Rapamune) may be used to shrink or slow the growth of subependymal giant cell astrocytomas (SEGAs) that can't be completely removed with surgery.

Larotrectinib (Vitrakvi) may be used to treat an astrocytoma that has spread (metastasized) or that can't be removed with surgery and doesn't respond to other treatments.

Bevacizumab (Avastin and biosimilars) is a monoclonal antibody that may be used to treat astrocytomas.

Trametinib (Mekinist) is a MEK inhibitor that may be used to treat astrocytomas. It is given in combination with the BRAF inhibitor dabrafenib (Tafinlar).

Find out more about targeted therapy for childhood brain and spinal cord tumours.

Children with cancer may be treated in a clinical trial. Clinical trials look at new ways to prevent, find and treat cancer. Find out more about clinical trials.