Understanding Brain Cancer: Stages

What “Stages” Mean

Once a brain tumor has been found, it’s important to know what stage it is. Knowing what stage your cancer is tells you how serious it is. The stage of brain cancer depends on the size of the cancer, lymph node involvement and if there is any spread of the tumor. It helps your doctor plan the right course of treatment.

The TNM staging system is used for all types of cancer, not just brain cancer. The letters TNM describe the amount and spread of cancer in your body.

  • T: indicates how large the tumor is.
  • N: indicates whether the cancer has spread to surrounding lymph nodes.
  • M: indicates metastasis, which means that cancer has spread to other body parts.

Stages are usually often labeled using Roman numerals 0 through IV (0-4). Higher numbers mean cancer has spread and the cancer is more advanced.

Brain tumors are grouped by grade. The term grade refers to the way the tumor cells look under a microscope:

Grade I: Tissue is benign. Cells look almost normal. They grow slowly.

Grade II: Tissue is malignant. Cells look less normal than in Grade I.

Grade III: Tissue is malignant. Cells look very abnormal. These abnormal cells are actively growing.

Grade IV: Tissue is malignant. Cells look the most abnormal and grow very quickly.

It is possible for a low-grade tumor to become a high-grade tumor over time. This change is more common in adults than in children.

Next: I’ve received my diagnosis. What do I do now? What questions do I need to ask my doctor? 

Back to “Understanding Brain Cancer: An Introduction”