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  • Stages of Brain Cancer

    Brain cancer is staged to help doctors and patients determine the best treatment strategy for each patient’s unique case. The term “staging” refers to the assessment of vaiours tumor characteristics, including but not limited to the location, size, and number of tumors.

    Below you will find both an overview of the brain tumor grading system and what is known as the collaborative staging system.


    Brain cancer grading describes the type, aggression, and size of a tumor.

    • Grade I: These tumors are non-cancerous and very slow-growing. Grade I tumors can typically be cured with surgery.
    • Grade II: These tumors are slow-growing, but may spread to other tissues.
    • Grade III: These tumors grow quickly. Grade III tumors will likely spread to other tissues. Under a microscope, Grade III brain cancer cells appear irregular. That is, they do not resemble the healthy cells located in surrounding tissues.
    • Grade IV: These tumors are fast-growing, they spread aggressively, and their cells are very irregular in appearance.
    • Grade V: This grade describes highly aggressive, large tumors whose cells appear extremely irregular under a microscope.


    This collaborative staging guide describes brain cancers across a spectrum beginning at 05 and ending at 99. Each numerical indicator denotes the location and/or how widespread the brain cancer has become. Below you will find a list of some of the more notable points on the collaboartive staging spectrum:

    • 05: Benign (non-cancerous) tumors.
    • 10: These tumors are located only in the cerebral hemispheres, which include the frontal, occipital, parietal, and temporal lobes.
    • 15: These tumors may develop in any location within the brain.
    • 20: These tumors have developed in at least one side of the cerebellum and the brain stem.
    • 30: These tumors are confined to parts of the brain known as the ventricles. Stage 30 tumors are beginning to spread into other areas of the brain.
    • 40: These tumors have begun to spread across the midline of the brain. Furthermore, stage 40 tumors have spread into multiple areas of the brain, including the contralateral hemisphere and corpus callosum (areas located in the central parts of the brain).
    • 50: These tumors are located in both cerebral hemispheres.
    • 60: These tumors have spread beyond the brain into the bones surrounding the brain (skull), major brain blood vessels, meninges, various nerves in the brain, and the spinal cord/canal.
    • 70: These tumors are located in, but not limited to the following areas: cells in the cerebral spinal fluids, nasal cavities, posterior pharynx (back of throat), and outside of the central nervous system.
    • 95: At this stage, the primary tumor can no longer be assessed. That is, the cancer has spread so significantly that the original site where the tumor first arose can not be identified.
    • 99: In this stage, the primary tumor cannot be assessed and the cancer’s metastasis is significant enough to render the assessement of all tumors practically impossible.

    The complete collaboartive staging guide can be found in the fourth addition of the American Joint Committee on Cancer (AJCC) Manual for Staging Cancer. The collaborative staging system is used in conjunction with the grading system (above) to help doctors and patients develop the most comprehensive treatment startegy possible.

    When the grading system and collaborative staging guide are used in conjunction, physicians and patients are able to manage their cancer treatment in the most effective way, thereby providing patients with the best possible prognosis. The brain is an extremely specialized organ, which is why staging brain cancer can be so much more complex than staging other cancer types.