A biopsy is when the surgeon removes a piece of the tumour. This can then be examined by a doctor who studies cell types (pathologist). They do tests to find out the type and grade of the tumour and check for biomarkers.
There are different ways to take a brain biopsy. Your surgeon will explain what to expect in your situation. Sometimes it is only safe to remove a tiny part of the tumour to look at under the microscope. But often the biopsy is taken as part of a larger operation to remove the tumour.
You usually have a biopsy taken under a general anaesthetic. But sometimes a local anaesthetic is used. During the operation the surgeon may take the biopsy:
- through a small hole they drill in the skull (burr hole)
- by removing a small area of skull over the tumour (craniotomy). This is called an open biopsy.
The surgeon uses scans taken before and sometimes during the operation to guide them while taking the biopsy.