Cancer stages

Stage IV cancer

Stage IV cancer, also known as stage 4 cancer, is a serious disease that requires immediate expert care. Patients who have been diagnosed with stage IV cancer may consider getting a second opinion to confirm the diagnosis and explore treatment options.

At Cancer Treatment Centers of America® (CTCA), we use a variety of tools, tests and procedures to confirm your stage IV diagnosis, determine where your cancer may have spread and develop a comprehensive treatment plan designed specifically for you. Stage IV cancer patients also may be eligible to participate in available clinical trials. Chat with us to set up an appointment with one of our cancer experts.

What is stage IV (stage 4) cancer?

Stage IV cancer is sometimes referred to as metastatic cancer, because it often means the cancer has spread from its origin to distant parts of the body. This stage may be diagnosed years after the initial cancer diagnosis and/or after the primary cancer has been treated or removed.

When a cancer metastasizes to a different part of the body, it is still defined by its original location. For instance, if breast cancer metastasizes to the brain, it is still considered breast cancer, not brain cancer. Many stage IV cancers have subcategories, such as stage IVA or stage IVB, which are often determined by the degree to which the cancer has spread throughout the body.

Liquid cancers, or blood cancers, such as leukemia, lymphoma or multiple myeloma, are staged differently than most other cancers because they may not always form solid tumors. Liquid cancers may be staged by a variety of factors, including:

  • The ratio of healthy blood cells to cancerous cells
  • The degree to which lymph nodes, the liver or spleen may be swollen
  • Whether the cancer has resulted in blood disorders such as anemia

Stage IV cancer is determined in the five most common cancers this way:

Stage IV (stage 4) breast cancer

The cancer has spread beyond the breast, underarm and internal mammary lymph nodes to other parts of the body near to or distant from the breast. Metastatic breast cancer most often spreads to the bones, brain, lungs and/or liver.

Learn more about breast cancer stages

Stage IV (stage 4) lung cancer

The cancer has spread beyond the lungs or from one lung to the other. Metastatic lung cancer most often spreads to the adrenal glands, bones, brain and/or liver.

Learn more about lung cancer stages

Stage IV (stage 4) prostate cancer

The cancer is found in other parts of the body, even after the prostate has been removed. Metastatic prostate cancer usually travels to the adrenal glands, liver, bones and/or lungs.

Learn more about prostate cancer stages

Stage IV (stage 4) colorectal cancer

The cancer has spread to one or more organs that are not near the colon. Metastasized colorectal cancer most commonly spreads to the liver, lungs and/or bones.

Learn more about colorectal cancer stages

Stage IV (stage 4) melanoma

The cancer cells have spread beyond the skin and local lymph nodes to distant lymph nodes, organs and/or other areas of skin. Metastasized melanoma may be found in the bones, brain, liver or lungs.

Learn more about melanoma stages

Most cancers are staged using some form of the TNM system. Doctors may also use the TNM system to help determine the extent of certain cancers in each stage. The TNM system stands for:

  • T (tumor), or the size of the original tumor
  • N (node), or whether the cancer is present in the lymph nodes
  • M (metastasis), or whether the cancer has spread to other parts of the body

Some cancers, especially liquid cancers, are staged using different established protocols. The Binet and Rai systems, for instance, are used to stage certain types of leukemia.

Cancers of the central nervous system (CNS) are graded rather than staged. Grade IV brain and spinal cancers are considered very aggressive and fast-growing. Tumors that have spread to the CNS from another location in the body are much more common than primary brain or spinal column tumors.