Currently, brain biopsy can be performed by open biopsy or stereotactic biopsy. Open biopsy can be easily performed for superficial lesions on the surface of the cerebral cortex. However, for small lesions, especially deep in the brain parenchyma, open biopsy can be difficult to obtain accurate tissue samples.

Tissue or cell samples can be taken from any part of the body. How the tissue is taken depends on where the tumor is and what type of cancer is suspected. For example, the methods used for a skin biopsy are very different from those used for a brain biopsy. Some types of biopsies remove an entire organ from the body. These biopsies are only performed by surgeons. Other types of biopsies remove tumor samples through a small needle or through an endoscope. These biopsies are usually performed by surgeons, but can also be performed by other doctors.