Lung cancer staging is the assessment of the extent to which lung cancer has spread from its original source. The information gathered from the staging process determines the stage of the disease, which assists the doctor in understanding the seriousness of the cancer, providing an optimal treatment plan, identifying potential clinical trials for viable treatment options, and even providing chances of survival (prognosis).
The staging system most often used for lung cancer is the American Joint Committee on Cancer (AJCC) TNM system, which is based on 3 key pieces of information:
- The size and extent of the main tumor (T)
- The spread to nearby (regional) lymph nodes (N)
- The spread (metastasis) (M) to other organs of the body
After determining a diagnosis of small cell (SCLC) or non-small cell lung cancer (NSCLC), additional testing determines if the cancer cells have spread (metastasized) within the chest or to other parts of the body. Information gathered determines the stage of the disease and the treatment plan.
Staging Small Cell Lung Cancer
Additional tests and procedures that may be used in the small cell lung cancer staging process include:
- Laboratory tests
- 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.
- MRI (magnetic resonance imaging)
- Endoscopic ultrasound (EUS)
- Lymph node biopsy: The removal of all or part of a lymph node. A pathologist views the tissue under a microscope to look for cancer cells.
- Radionuclide bone scan
Stages of Small Cell Lung Cancer:
Small cell lung cancer falls under one of two categories: limited and extensive.
In limited-stage small cell lung cancer, cancer is found in one lung, the tissues between the lungs, and nearby lymph nodes only. Alternatively, extensive-stage small cell lung cancer has spread outside of the lung in which it began or to other parts of the body.
Staging Non-Small Cell Lung Cancer
Additional tests and procedures that may be used in the non-small cell lung cancer staging process include:
- Lymph node biopsy
- Mediastinoscopy: A surgical procedure to look at the organs, tissues, and lymph nodes between the lungs for abnormal areas. An incision (cut) is made at the top of the breastbone, and a mediastinoscope is inserted into the chest. A mediastinoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue or lymph node samples, which are checked under a microscope for signs of cancer.
- Anterior mediastinotomy: A surgical procedure to look at the organs and tissues between the lungs and between the breastbone and heart for abnormal areas. This is also called the Chamberlain procedure.
Stages of Non-Small Cell Lung Cancer:
The American Cancer Society created a table that helps convert your TNM status into a stage.
Stage |
Stage grouping |
Stage description* |
Occult (hidden) cancer |
TX N0 M0 |
The main tumor can’t be assessed for some reason, or cancer cells are seen in a sample of sputum or other lung fluids, but the cancer isn’t found with other tests, so its location can’t be determined (TX). The cancer is not thought to have spread to nearby lymph nodes (N0) or to distant parts of the body (M0). |
0 |
Tis N0 M0 |
The tumor is found only in the top layers of cells lining the air passages, but it has not invaded deeper into other lung tissues (Tis). The cancer has not spread to nearby lymph nodes (N0) or to distant parts of the body (M0). |
IA1 |
T1mi N0 M0 |
The cancer is a minimally invasive adenocarcinoma. The tumor is no larger than 3 centimeters (cm) across, and the part that has invaded into deeper lung tissues is no more than ½ cm across. The cancer has not spread to nearby lymph nodes (N0) or to distant parts of the body (M0). |
OR |
||
T1a N0 M0 |
The tumor is no larger than 1 cm across, it has not reached the membranes that surround the lungs, and it does not affect the main branches of the bronchi (T1a). The cancer has not spread to nearby lymph nodes (N0) or to distant parts of the body (M0). |
|
IA2 |
T1b N0 M0 |
The tumor is larger than 1 cm but no larger than 2 cm across. It has not reached the membranes that surround the lungs, and it does not affect the main branches of the bronchi (T1b). The cancer has not spread to nearby lymph nodes (N0) or to distant parts of the body (M0). |
IA3 |
T1c N0 M0 |
The tumor is larger than 2 cm but no larger than 3 cm across. It has not reached the membranes that surround the lungs, and it does not affect the main branches of the bronchi (T1c). The cancer has not spread to nearby lymph nodes (N0) or to distant parts of the body (M0). |
IB |
T2a N0 M0 |
The tumor has one or more of the following features (T2a):
The cancer has not spread to nearby lymph nodes (N0) or to distant parts of the body (M0). |
IIA |
T2b N0 M0 |
The tumor has one or more of the following features (T2b):
The cancer has not spread to nearby lymph nodes (N0) or to distant parts of the body (M0). |
IIB |
T1a/T1b/T1c N1 M0 |
The tumor is no larger than 3 cm across, has not grown into the membranes that surround the lungs, and does not affect the main branches of the bronchi (T1). It has spread to lymph nodes within the lung and/or around the area where the bronchus enters the lung (hilar lymph nodes). These lymph nodes are on the same side as the cancer (N1). The cancer has not spread to distant parts of the body (M0). |
OR |
||
T2a/T2b N1 M0 |
The tumor has one or more of the following features (T2):
The cancer has also spread to lymph nodes within the lung and/or around the area where the bronchus enters the lung (hilar lymph nodes). These lymph nodes are on the same side as the cancer (N1). The cancer has not spread to distant parts of the body (M0). |
|
OR |
||
T3 N0 M0 |
The tumor has one or more of the following features (T3):
The cancer has not spread to nearby lymph nodes (N0) or distant parts of the body (M0). |
|
IIIA |
T1a/T1b/T1c N2 M0 |
The cancer is no larger than 3 cm across, has not grown into the membranes that surround the lungs, and does not affect the main branches of the bronchi (T1). The cancer has spread to lymph nodes around the carina (the point where the windpipe splits into the left and right bronchi) or in the space between the lungs (mediastinum). These lymph nodes are on the same side as the main lung tumor (N2). The cancer has not spread to distant parts of the body (M0). |
OR |
||
T2a/T2b N2 M0 |
The tumor has one or more of the following features (T2):
The cancer has spread to lymph nodes around the carina (the point where the windpipe splits into the left and right bronchi) or in the space between the lungs (mediastinum). These lymph nodes are on the same side as the main lung tumor (N2). The cancer has not spread to distant parts of the body (M0). |
|
OR |
||
T3 N1 M0 |
The tumor has one or more of the following features (T3):
The cancer has also spread to lymph nodes within the lung and/or around the area where the bronchus enters the lung (hilar lymph nodes). These lymph nodes are on the same side as the cancer (N1). The cancer has not spread to distant parts of the body (M0). |
|
OR |
||
T4 N0 or N1 M0 |
The tumor has one or more of the following features (T4):
The cancer may or may not have spread to lymph nodes within the lung and/or around the area where the bronchus enters the lung (hilar lymph nodes). Any affected lymph nodes are on the same side as the cancer (N0 or N1). The cancer has not spread to distant parts of the body (M0). |
|
IIIB
|
T1a/T1b/T1c N3 M0 |
The cancer is no larger than 3 cm across, has not grown into the membranes that surround the lungs, and does not affect the main branches of the bronchi (T1). The cancer has spread to lymph nodes near the collarbone on either side of the body, and/or has spread to hilar or mediastinal lymph nodes on the other side of the body from the main tumor (N3). The cancer has not spread to distant parts of the body (M0). |
OR |
||
T2a/T2b N3 M0 |
The tumor has one or more of the following features (T2):
The cancer has spread to lymph nodes near the collarbone on either side of the body, and/or has spread to hilar or mediastinal lymph nodes on the other side of the body from the main tumor (N3). The cancer has not spread to distant parts of the body (M0). |
|
OR |
||
T3 N2 M0 |
The tumor has one or more of the following features (T3):
The cancer has spread to lymph nodes around the carina (the point where the windpipe splits into the left and right bronchi) or in the space between the lungs (mediastinum). These lymph nodes are on the same side as the main lung tumor (N2). The cancer has not spread to distant parts of the body (M0). |
|
OR |
||
T4 N2 M0 |
The tumor has one or more of the following features (T4):
The cancer has spread to lymph nodes around the carina (the point where the windpipe splits into the left and right bronchi) or in the space between the lungs (mediastinum). These lymph nodes are on the same side as the main lung tumor (N2). The cancer has not spread to distant parts of the body (M0). |
|
IIIC |
T3 N3 M0 |
The tumor has one or more of the following features (T3):
The cancer has spread to lymph nodes near the collarbone on either side of the body, and/or has spread to hilar or mediastinal lymph nodes on the other side of the body from the main tumor (N3). The cancer has not spread to distant parts of the body (M0). |
OR |
||
T4 N3 M0 |
The tumor has one or more of the following features (T4):
The cancer has spread to lymph nodes near the collarbone on either side of the body, and/or has spread to hilar or mediastinal lymph nodes on the other side of the body from the main tumor (N3). The cancer has not spread to distant parts of the body (M0). |
|
IVA |
Any T Any N M1a |
The cancer can be any size and may or may not have grown into nearby structures (any T). It may or may not have reached nearby lymph nodes (any N). In addition, any of the following is true (M1a):
|
OR |
||
Any T Any N M1b |
The cancer can be any size and may or may not have grown into nearby structures (any T). It may or may not have reached nearby lymph nodes (any N). It has spread as a single tumor outside of the chest, such as to a distant lymph node or an organ such as the liver, bones, or brain (M1b). |
|
IVB |
Any T Any N M1c |
The cancer can be any size and may or may not have grown into nearby structures (any T). It may or may not have reached nearby lymph nodes (any N). It has spread as more than one tumor outside the chest, such as to distant lymph nodes and/or to other organs such as the liver, bones, or brain (M1c). |
*The following additional categories are not listed in the table above:
- T0: There is no evidence of a primary tumor.
- NX: Nearby lymph nodes cannot be assessed due to lack of information.