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Stages of Non-Small Cell Lung Cancer

After lung cancer has been diagnosed, tests are done to find out if cancer cells have spread within the lungs or to other parts of the body.

The process used to find out if cancer has spread within the lungs or to other parts of the body is called staging. The information gathered from the staging process determines the stage of the disease. It is important to know the stage in order to plan treatment. Some of the tests used to diagnose non-small cell lung cancer are also used to stage the disease. For more information, see the General Information section.

Other tests and procedures that may be used in the staging process include the following:

  • MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body, such as the brain. This procedure is also called nuclear magnetic resonance imaging (NMRI).
  • CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, such as the brain, abdomen, and lymph nodes, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
  • PET scan (positron emission tomography scan): A procedure to find cancer cells in the body. A small amount of radioactive glucose (sugar) is injected into a vein. The PET scanner rotates around the body and makes a picture of where glucose is being used in the body. Malignant tumor cells show up brighter in the picture because they are more active and take up more glucose than normal cells do.
  • Bone scan: A procedure to check if there are rapidly dividing cells, such as cancer cells, in the bone. A very small amount of radioactive material is injected into a vein and travels through the bloodstream. The radioactive material collects in the bones with cancer and is detected by a scanner.
  • Pulmonary function test (PFT): A test to see how well the lungs are working. It measures how much air the lungs can hold and how quickly air moves into and out of the lungs. It also measures how much oxygen is used and how much carbon dioxide is given off during breathing. This is also called lung function test.
  • Bone marrow aspiration and biopsy: The removal of bone marrow, blood, and a small piece of bone by inserting a hollow needle into the hipbone or breastbone. A pathologist views the bone marrow, blood, and bone under a microscope to look for signs of cancer.

There are three ways that cancer spreads in the body.

Cancer can spread through tissue, the lymph system, and the blood:

  • Tissue. The cancer spreads from where it began by growing into nearby areas.
  • Lymph system. The cancer spreads from where it began by getting into the lymph system. The cancer travels through the lymph vessels to other parts of the body.
  • Blood. The cancer spreads from where it began by getting into the blood. The cancer travels through the blood vessels to other parts of the body.

Cancer may spread from where it began to other parts of the body.

When cancer spreads to another part of the body, it is called metastasis. Cancer cells break away from where they began (the primary tumor) and travel through the lymph system or blood.

  • Lymph system. The cancer gets into the lymph system, travels through the lymph vessels, and forms a tumor (metastatic tumor) in another part of the body.
  • Blood. The cancer gets into the blood, travels through the blood vessels, and forms a tumor (metastatic tumor) in another part of the body.

The metastatic tumor is the same type of cancer as the primary tumor. For example, if non-small cell lung cancer spreads to the brain, the cancer cells in the brain are actually lung cancer cells. The disease is metastatic lung cancer, not brain cancer.

The following stages are used for non-small cell lung cancer:

Occult (hidden) stage

In the occult (hidden) stage, cancer cannot be seen by imaging or bronchoscopy. Cancer cells are found in sputum or bronchial washings (a sample of cells taken from inside the airways that lead to the lungs). Cancer may have spread to other parts of the body.

Stage 0

In stage 0, abnormal cells are found in the lining of the airways. These abnormal cells may become cancer and spread into nearby normal tissue. Stage 0 may be adenocarcinoma in situ (AIS) or squamous cell carcinoma in situ (SCIS).

Stage I

In stage I, cancer has formed. Stage I is divided into stages IA and IB.

  • Stage IA:

    The tumor is in the lung only and is 3 centimeters or smaller. Cancer has not spread to the lymph nodes.

  • Stage IB:

    The tumor is larger than 3 centimeters but not larger than 4 centimeters. Cancer has not spread to the lymph nodes.

    or

    The tumor is 4 centimeters or smaller and one or more of the following is found:

    • Cancer has spread to the main bronchus, but has not spread to the carina.
    • Cancer has spread to the innermost layer of the membrane that covers the lung.
    • Part of the lung or the whole lung has collapsed or has developed pneumonitis.

    Cancer has not spread to the lymph nodes.

Stage II

Stage II is divided into stages IIA and IIB.

  • Stage IIA:

    The tumor is larger than 4 centimeters but not larger than 5 centimeters. Cancer has not spread to the lymph nodes and one or more of the following may be found:

    • Cancer has spread to the main bronchus, but has not spread to the carina.
    • Cancer has spread to the innermost layer of the membrane that covers the lung.
    • Part of the lung or the whole lung has collapsed or has developed pneumonitis.
  • Stage IIB:

    The tumor is 5 centimeters or smaller and cancer has spread to lymph nodes on the same side of the chest as the primary tumor. The lymph nodes with cancer are in the lung or near the bronchus. Also, one or more of the following may be found:

    • Cancer has spread to the main bronchus, but has not spread to the carina.
    • Cancer has spread to the innermost layer of the membrane that covers the lung.
    • Part of the lung or the whole lung has collapsed or has developed pneumonitis.

    or

    Cancer has not spread to the lymph nodes and one or more of the following is found:

    • The tumor is larger than 5 centimeters but not larger than 7 centimeters.
    • There are one or more separate tumors in the same lobe of the lung as the primary tumor.
    • Cancer has spread to any of the following:
      • The membrane that lines the inside of the chest wall.
      • Chest wall.
      • The nerve that controls the diaphragm.
      • Outer layer of tissue of the sac around the heart.

Stage III

Stage III is divided into stages IIIA, IIIB, and IIIC.

  • Stage IIIA:

    The tumor is 5 centimeters or smaller and cancer has spread to lymph nodes on the same side of the chest as the primary tumor. The lymph nodes with cancer are around the trachea or aorta, or where the trachea divides into the bronchi. Also, one or more of the following may be found:

    • Cancer has spread to the main bronchus, but has not spread to the carina.
    • Cancer has spread to the innermost layer of the membrane that covers the lung.
    • Part of the lung or the whole lung has collapsed or has developed pneumonitis.

    or

    Cancer has spread to lymph nodes on the same side of the chest as the primary tumor. The lymph nodes with cancer are in the lung or near the bronchus. Also, one or more of the following is found:

    • The tumor is larger than 5 centimeters but not larger than 7 centimeters.
    • There are one or more separate tumors in the same lobe of the lung as the primary tumor.
    • Cancer has spread to any of the following:
      • The membrane that lines the inside of the chest wall.
      • Chest wall.
      • The nerve that controls the diaphragm.
      • Outer layer of tissue of the sac around the heart.

    or

    Cancer may have spread to lymph nodes on the same side of the chest as the primary tumor. The lymph nodes with cancer are in the lung or near the bronchus. Also, one or more of the following is found:

    • The tumor is larger than 7 centimeters.
    • There are one or more separate tumors in a different lobe of the lung with the primary tumor.
    • The tumor is any size and cancer has spread to any of the following:
      • Trachea.
      • Carina.
      • Esophagus.
      • Breastbone or backbone.
      • Diaphragm.
      • Heart.
      • Major blood vessels that lead to or from the heart (aorta or vena cava).
      • Nerve that controls the larynx (voice box).
  • Stage IIIB:

    The tumor is 5 centimeters or smaller and cancer has spread to lymph nodes above the collarbone on the same side of the chest as the primary tumor or to any lymph nodes on the opposite side of the chest as the primary tumor. Also, one or more of the following may be found:

    • Cancer has spread to the main bronchus, but has not spread to the carina.
    • Cancer has spread to the innermost layer of the membrane that covers the lung.
    • Part of the lung or the whole lung has collapsed or has developed pneumonitis.

    or

    The tumor may be any size and cancer has spread to lymph nodes on the same side of the chest as the primary tumor. The lymph nodes with cancer are around the trachea or aorta, or where the trachea divides into the bronchi. Also, one or more of the following is found:

    • There are one or more separate tumors in the same lobe or a different lobe of the lung with the primary tumor.
    • Cancer has spread to any of the following:
      • The membrane that lines the inside of the chest wall.
      • Chest wall.
      • The nerve that controls the diaphragm.
      • Outer layer of tissue of the sac around the heart.
      • Trachea.
      • Carina.
      • Esophagus.
      • Breastbone or backbone.
      • Diaphragm.
      • Heart.
      • Major blood vessels that lead to or from the heart (aorta or vena cava).
      • Nerve that controls the larynx (voice box).
  • Stage IIIC:

    The tumor may be any size and cancer has spread to lymph nodes above the collarbone on the same side of the chest as the primary tumor or to any lymph nodes on the opposite side of the chest as the primary tumor. Also, one or more of the following is found:

    • There are one or more separate tumors in the same lobe or a different lobe of the lung with the primary tumor.
    • Cancer has spread to any of the following:
      • The membrane that lines the inside of the chest wall.
      • Chest wall.
      • The nerve that controls the diaphragm.
      • Outer layer of tissue of the sac around the heart.
      • Trachea.
      • Carina.
      • Esophagus.
      • Breastbone or backbone.
      • Diaphragm.
      • Heart.
      • Major blood vessels that lead to or from the heart (aorta or vena cava).
      • Nerve that controls the larynx (voice box).

Stage IV

Stage IV is divided into stages IVA and IVB.

  • Stage IVA:

    The tumor may be any size and cancer may have spread to the lymph nodes. One or more of the following is found:

    • There are one or more tumors in the lung that does not have the primary tumor.
    • Cancer is found in the lining around the lungs or the sac around the heart.
    • Cancer is found in fluid around the lungs or the heart.
    • Cancer has spread to one place in an organ not near the lung, such as the brain, liver, adrenal gland, kidney, bone, or to a lymph node that is not near the lung.
  • Stage IVB:

    Cancer has spread to multiple places in one or more organs that are not near the lung.

Non-small cell lung cancer can recur (come back) after it has been treated.

The cancer may come back in the brain, lung, or other parts of the body.

This information is not intended to replace the advice of a doctor. Navigating Care disclaims any liability for the decisions you make based on this information. This information was sourced and adapted from Adapted from the National Cancer Institute's Physician Data Query (PDQ®) Cancer Information Summaries on www.cancer.gov.