A thorough and accurate diagnosis is the first step in developing a brain cancer treatment plan. A multidisciplinary team of experts uses a variety of tests and tools for diagnosing brain cancer, evaluating the disease and customizing a treatment plan based on each individual patient’s disease and situation. Throughout treatment, imaging tests track the size of the tumor(s) and monitor response to treatment, so the treatment plan may be modified as needed.
Common tools used for diagnosing brain cancer include:Biopsy
Whenever possible, a full surgical resection of the cancerous tissue is performed. If such a resection threatens neurological function, a lesser resection, or simple biopsy, is performed.
A biopsy for brain cancer involves the removal of a small amount of the cancerous brain tissue. This helps evaluate the tumor in order to develop a treatment plan. A needle biopsy may be performed for tumors in difficult-to-reach or critical areas of the brain.Lab tests
The main lab test for brain cancer is advanced genomic testing, which analyzes a tumor’s genomic profile to look for DNA alterations that may be causing the cancer to grow. By identifying the mutations (changes) in a cancer cell"s genome, doctors may better understand the tumor’s behavior and tailor treatment based on these findings.Nuclear medicine bone scan
By capturing images of bones on a computer screen or on film, a nuclear medicine bone scan may reveal the location of the cancer, as well as whether the brain cancer has spread to the bone. To perform the scan, a small dose of radioactive material is injected into a blood vessel, where it travels through the bloodstream, gathers in the bones, and is detected by a scanner through nuclear imaging.Angiography
This procedure uses X-rays to obtain multiple, detailed, 3-D images of the blood vessels in the brain. An angiography may be used to plan the surgical resection of a tumor near an area of the brain with many blood vessels. Sometimes, this test is used to embolize (close off) blood vessels feeding a tumor prior to surgery.Other imaging tests
Imaging tests for brain cancer produce pictures of the brain to determine the location and grade of brain tumors. A contrast agent may be used to distinguish normal and abnormal brain tissue.
Imaging tests used in brain cancer diagnosis include:
MRI (magnetic resonance imaging): MRIs are used to look for brain and spinal cord tumors because they tend to provide greater detail than CT scans. However, for the bones and skull, MRI does not provide the same image quality as CT scans and, therefore, may not show the effects of tumors on the skull.
CT (computed tomography) scan: CT scans create detailed images of the body’s soft tissues and may be performed when MRI is not an option, such as with overweight or claustrophobic patients. CT scans also show greater detail of bone structures near the tumor.
PET (positron emission tomography) scan: PET scans are more often used for fast-growing, high-grade tumors. Following treatment, a PET scan may be performed to determine whether tumor tissue remains.
Next topic: How is brain cancer treated?