Non-Small Cell Lung Cancer: Stages

What does the stage of a cancer mean?

The stage of a cancer is how much cancer there is and how far it has spread in your body. Your healthcare provider uses exams and tests to find out the size of the tumor and where it is. Scans can also show if the cancer has grown into nearby areas, and if it has spread to other parts of your body. The stage is one of the most important things to know when deciding how to treat the cancer.

The TNM system for non-small cell lung cancer (NSCLC)

The most commonly used system to stage non-small cell lung cancer (NSCLC) is the TNM system from the American Joint Committee on Cancer. Be sure to ask your healthcare provider to explain the stage of your cancer to you in a way you can understand.

The first step in staging is to find the value for each part of the TNM system. Here's what the letters stand for in the TNM system:

  • T tells how large a tumor is and whether it has grown into nearby tissues.

  • N tells whether the lymph nodes near the tumor have cancer in them.

  • M tells whether the cancer has spread ( metastasized) to other organs in the body, like the brain, bones, bone marrow, or liver.

Numbers or letters after T, N, and M provide more details about each of these factors.

What are the stage groupings for NSCLC?

The T, N, and M values from the TNM system are used to put these cancers into stage groupings. The groupings give an overall description of your cancer. A stage grouping is listed as a Roman numeral and can have a value of I (1), II (2), III (3), or IV (4). The higher the number, the more advanced the cancer is.

Below are the stage groupings for NSCLC and what they mean.

Occult (hidden) cancer

This means you have cancer cells in your sputum (the mucus from the lungs) or other lung fluids, but the main tumor can't be found on other tests or scans. The cancer has not spread to your lymph nodes or to other parts of your body.

You may hear your healthcare provider use these TNM terms for this stage: TX, N0, M0.

Stage 0 or carcinoma in situ

The cancer is very tiny and is only in the cells lining your air passages. It has not spread deeper into lung tissues or spread outside the lungs.

You may hear your healthcare provider use these TNM terms for this stage: Tis ( in situ ), N0, M0.

Stage I

In stage I, the cancer has not spread to lymph nodes or other parts of the body. This stage is divided into sub-groups using letters and numbers.

Stage IA1. The cancer is 1 of these:

  • The tumor is only in the lung. It's not bigger than 3 cm (centimeters) across. The part of the tumor that's deeper in the lung tissues is no more than 1/2 cm across. The TNM terms for this stage are T1mi (mi stands for minimally invasive), N0, M0.
  • The tumor is only in the lung and is not more than 1 cm across. It has not spread into the sac-like membrane around the lungs or to the main airways (the bronchi). The TNM terms for this stage are T1a, N0, M0.
Stage IA2. The tumor is only in the lung and is bigger than 1 cm, but less than 2 cm across. It has not spread into the sac-like membrane around the lungs or to the main airways (the bronchi). The TNM terms for this stage are T1b, N0, M0.

Stage IA3. The tumor is only in the lung. It's bigger than 2 cm, but less than 3 cm across. It has not spread into the sac-like membrane around the lungs or to the main airways (the bronchi). The TNM terms for this stage are T1c, N0, M0.

Stage IB. The tumor has not spread outside the lungs and is one or more of these:

  • Bigger than 3 cm, but less than 4 cm across
  • Grown into one of the bronchi but is not within 2 cm of the carina. The carina is where the windpipe splits into the left and right bronchi. The tumor is not larger than 4 cm across.
  • Grown into the sac-like membrane around the lungs and is not larger than 4 cm across
  • Partly blocking the airways and is not larger than 4 cm across
The TNM terms for this stage are T2a, N0, M0.

Stage II

This stage is divided into subgroups using letters and numbers.

Stage IIA. The tumor has not spread outside the lungs and is one or more of these:

  • Bigger than 4 cm, but less than 5 cm across

  • Grown into one of the bronchi but not within 2 cm of the carina. The tumor is larger than 4 cm but less than 5 cm across.

  • Grown into the sac-like membrane around the lungs. The tumor is larger than 4 cm but less than 5 cm across.

  • Partly blocking the airways. The tumor is larger than 4 cm but less than 5 cm across.

The TNM terms for this stage are T2b, N0, M0.

Stage IIB can be any of these:

1. The tumor is not bigger than 3 cm across. It has not spread into the sac-like membrane that surrounds the lung or to the main airways (the bronchi). It has spread into nearby lymph nodes on the same side as the cancer. It has not spread to other parts of the body. The TNM terms for this stage are T1a or T1b or T1c, N1, M0.

2. Or the tumor is one or more of these:

  • It's bigger than 3 cm, but less than 5 cm across.

  • It has grown into one of the bronchi but not within 2 cm of the carina. The tumor is less than 5 cm across.

  • It has grown into the sac-like membrane that surrounds the lung and is less than 5 cm across.

  • It's partly blocking the airways and is less than 5 cm across.

It also has spread into nearby lymph nodes on the same side as the cancer. It has not spread to other parts of the body. The TNM terms for this stage are T2a or T2b, N1, M0.

3. Or the tumor is one or more of these:

  • It's bigger than 5 cm, but less than 7 cm across.

  • It has grown into the sac-like membrane that surrounds the lung, the chest wall, the phrenic nerve, or the sac-like membrane that surrounds the heart

  • There are two or more tumors in the same lobe of the lung.

It has not spread into nearby lymph nodes or to other parts of the body. The TNM terms for this stage are T3, N0, M0.

Stage III

This stage is divided into subgroups using letters and numbers.

Stage IIIA can be any of these:

1. The tumor is no bigger than 3 cm across. It has not spread into the sac-like membrane that surrounds the lung or to the main airways (the bronchi). It has spread to lymph nodes between the lungs or around the place where the windpipe (trachea) splits into the two main bronchi on the same side as the cancer. It has not spread to other parts of the body. The TNM terms for this stage are T1a or T1b or T1c, N2, M0.

2. Or the tumor is one or more of these:

  • It's bigger than 3 cm, but less than 5 cm across.

  • It has grown into one of the bronchi but not within 2 cm of the carina. The tumor isn't larger than 5 cm across.

  • It has grown into the sac-like membrane that surrounds the lung and isn't larger than 5 cm across.

  • It's partly blocking the airways and isn't larger than 5 cm across.

It has also spread to lymph nodes between the lungs or around the place where the windpipe (trachea) splits into the two main bronchi on the same side as the cancer.

It has not spread to other parts of the body. The TNM terms for this stage are T2a or T2b, N2, M0.

3. Or the tumor is one or more of these:

  • It's bigger than 5 cm, but less than 7 cm across.

  • There are two or more tumors in the same lobe of the lung.
  • It has grown into the sac-like membrane that surrounds the lung, the chest wall, the phrenic nerve, or the sac-like membrane that surrounds the heart.

It has also spread to lymph nodes inside the lung or around the place where the bronchi enter the lung on the same side as the cancer.

It has not spread to other parts of the body. The TNM terms for this stage are T3, N1, M0.

4. Or the tumor is one or more of these:

  • It's bigger than 7 cm across.

  • It has grown into the space between the lungs, the windpipe (trachea), the place where the windpipe (trachea) splits into the two main bronchi, the heart, large blood vessels near the heart, the esophagus, the diaphragm, or the spine.

  • There are two or more tumors in the same lobe of the lung.

It may have spread to lymph nodes inside the lung, around the place where the bronchi enter the lung, or both. Nodes with cancer are on the same side as the main tumor. It has not spread to other parts of the body. The TNM terms for this stage are T4, N0 or N1, M0.

Stage IIIB can be any of these:

1. The tumor is no bigger than 3 cm across. It has not spread into the sac-like membrane that surrounds the lung or to the main airways (the bronchi). It has spread to lymph nodes between the lungs, around the place where the windpipe (trachea) splits into the two main bronchi in the lung that doesn't have the main tumor, or both. It has spread to lymph nodes near either collarbone. It has not spread to other parts of the body. The TNM terms for this stage are T1a or T1b or T1c, N3, M0.

2. Or the tumor is one or more of these:

  • It's bigger than 3 cm, but less than 5 cm across.

  • It has grown into one of the bronchi but not within 2 cm of the carina. The tumor isn't larger than 5 cm across.

  • It has grown into the sac-like membrane that surrounds the lung but isn't larger than 5 cm across.

  • It's partly blocking the airways but isn't larger than 5 cm across.

It has also spread to lymph nodes between the lungs, around the place where the windpipe (trachea) splits into the two main bronchi in the lung that doesn't have cancer, or both. It has spread to lymph nodes near the collarbones on either side of the body. It has not spread to other parts of the body. The TNM terms for this stage are T2a or T2b, N3, M0.

3. Or the tumor is one or more of these:

  • It's bigger than 5 cm, but less than 7 cm across.

  • It has grown into the sac-like membrane that surrounds the lung, the chest wall, the phrenic nerve, or the sac-like membrane that surrounds the heart.

  • There are two or more tumors in the same lobe of the lung.

It has also spread to lymph nodes between the lungs or around the place where the bronchi enter the lung. The nodes with cancer are on the same side as the main tumor. It has not spread to other parts of the body. The TNM terms for this stage are T3, N2, M0.

4. Or the tumor is one or more of these:

  • It's bigger than 7 cm across.

  • It has grown into the space between the lungs, the windpipe (trachea), the place where the windpipe (trachea) splits into the two main bronchi, the heart, large blood vessels near the heart, the esophagus, the diaphragm, or the spine.

  • There are two or more tumors in the different lobes of the same lung.

It has spread to lymph nodes between the lungs or around the place the windpipe (trachea) splits into the two main bronchi. Nodes with cancer are on the same side as the main tumor. It has not spread to other parts of the body. The TNM terms for this stage are T4, N2, M0.

Stage IIIC can be either of these:

1. The tumor is one or more of these:

  • It's bigger than 5 cm, but less than 7 cm across.

  • It has grown into the sac-like membrane that surrounds the lungs, the chest wall, the phrenic nerve, or the sac-like membrane that surrounds the heart.

  • There are two or more tumors in the same lobe of the lung.

It has spread to lymph nodes between the lungs or around the place the windpipe (trachea) splits into the two main bronchi in the lung without cancer. It has spread to lymph nodes near the collarbones on either side of the body. It has not spread to other parts of the body. The TNM terms for this stage are T3, N3, M0.

2. Or the tumor is one or more of these:

  • It's bigger than 7 cm across.

  • It has grown into the space between the lungs, the windpipe (trachea), the place where the windpipe (trachea) splits into the two main bronchi, the heart, large blood vessels near the heart, the esophagus, the diaphragm, or the spine.

  • There are two or more tumors in the different lobes of the same lung.

It may have spread to lymph nodes between the lungs or around the place where the windpipe (trachea) splits into the two main bronchi in the lung without cancer. It has spread to lymph nodes near the collarbone on either side of the body. It has not spread to other parts of the body. The TNM terms for this stage are T4, N3, M0.

Stage IV. This stage is divided into subgroups using letters and numbers.

Stage IVA can be either of these:

1. The tumor can be any size and may have grown into nearby tissues or lymph nodes. It's also one of these:

  • It has spread to the other lung.

  • Cancer cells have been found in the fluid around the lung.

  • Cancer cells have been found in the fluid around the heart.

The TNM terms for this stage are any T, any N, M1a.

2. Or the tumor can be any size and may have grown into nearby tissues or lymph nodes. It has also spread to one tumor outside the chest, such as a distant lymph node or another organ like the liver, bone, or brain. The TNM terms for this stage are any T, any N, M1b.

Stage IVB. The tumor is any size and may have grown into nearby tissues or lymph nodes. It has spread to more than one tumor outside the chest, such as a distant lymph node or another organ like the liver, bone, or brain. The TNM terms for this stage are any T, any N, M1c.

Talking with your healthcare provider

Once your cancer is staged, talk with your healthcare provider about what the stage means for you. Ask your healthcare provider to explain the details of your cancer to you in a way you can understand. Ask any questions and talk about your concerns.