A biopsy is a type of surgery in which a sample of the tumour is taken. It is the best way to get an accurate diagnosis, because sometimes brain scans do not give enough information about the type of tumour. The best way to find out the type of tumour is for a pathologist to study the tumour cells under a microscope. In this case, the diagnosis is made a few days after the biopsy. A biopsy is often done as part of surgery to remove the tumour.
For detailed information about surgery, please see the "Treatment" section.
The neurosurgeon removes a small sample of brain tumour tissue. The neurosurgeon then gives the tumour sample to a pathologist. After studying the tissue, the pathologist will know what type of tumour it is, and whether it is cancer.
In some cases, the surgeon will remain in the operating room while the tissue is being studied. This is called an intra-operative biopsy or quick section. Once the surgeon knows the type of tumour, they will then make a decision. They may choose to remove the rest of the tumour right away.
The other option is to end the operation, because radiation or chemotherapy would be better treatments. The intra-operative biopsy will tell the type of tumour, but the diagnosis will be confirmed a few days later after the pathologist has had more time to study the tissue sample.
What types of biopsies are there?
There are two types of biopsies: an open and a closed biopsy. Depending on the location of the tumour and the risks involved, the neurosurgeon will determine the best type of biopsy that is required.
In an open biopsy, a small part of the skull is cut away so that the surgeon can remove the tumour tissue. The bone is then replaced.
In a closed biopsy, a special stereotactic frame will be placed on your child’s head before a scan is done to show exactly where the tumour is. The surgeon will make a small hole in the skull. A thin probe is used to take a small sample of tumour.
What happens after the biopsy?
Your child will go to the Post Anaesthetic Care Unit, also called the PACU. You may also hear this unit called the Recovery Room. Specially trained nurses will watch your child. These nurses will check your child's breathing, heartbeat, temperature, and blood pressure regularly.
Your child will wake up soon after the biopsy. You may be with your child as soon as she wakes up.
What are the risks and side effects of a biopsy?
Like any invasive surgery, a biopsy has some risks. These include risks of complications from anaesthetic, risks of complications from surgery, and late effects from surgery. Most side effects of biopsy are minor and transient, meaning that they will go away after a short time.
Your child may have some side effects from the anaesthetic. For example, your child may feel dizzy, grumpy, have a sore throat and cough, or feel sick to the stomach. These types of side effects are usually minor.
There is a very small chance that your child may have a serious problem during or after the biopsy, such as a reaction to the anaesthetic, brain injury, or cardiac arrest. The anaesthesiologist will watch your child very closely and will be ready to deal with these problems. If your child has a serious problem during or after the anaesthetic he or she may have to stay at the hospital longer.
There is a small amount of risk from surgery, including risks of infection, bleeding (hemorrhage) and fluid build-up (edema). If your child experiences swelling, she may also have headaches associated with the swelling.
There is a chance that the scar from the biopsy may trigger seizures later on.
Your child's doctor will help you to understand the risks associated with surgery as well as the potential benefits.
What should I tell my child?
To help your child be less nervous, explain what will happen in simple words that they can understand. Tell them that they need to have an operation so that the doctors can find out how to make them get better. Let them know that the operation involves making a cut to take away part of the bone so that the doctors can remove tissue from their brain. Tell them that they will be asleep during the operation and will not feel any pain.
Sometimes biopsies are done when the child is awake, if the tumour is located in an area of the brain that controls language. If this is the case for your child, let them know that they will be awake but that they will have pain medication and will not feel any pain. Your treatment team will provide you with more information on how you can prepare your child for a biopsy.