Cancer staging is the process of gathering information to determine the location and extent of the lung cancer and if it has spread to other parts of the body. 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.
After determining a diagnosis of small cell or non-small cell lung cancer, additional testing determines if the cancer cells have spread within the chest or to other parts of the body. Information gathered determines the type and stage of your lung cancer and your individualized lung cancer treatment plan.
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:
- Limited-Stage Small Cell Lung Cancer
- In limited-stage small cell lung cancer, cancer is found in one lung, the tissues between the lungs, and nearby lymph nodes only.
- Extensive-Stage Small Cell Lung Cancer
- In extensive-stage small cell lung cancer, cancer has spread outside of the lung in which it began or to other parts of the body.
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:
- Occult (hidden) stage: In the occult (hidden) stage, cancer cells are found in sputum (mucus coughed up from the lungs), but no tumor can be found in the lung by imaging or bronchoscopy, or the primary tumor is too small to be checked.
- Stage 0 (Carcinoma in Situ): In stage 0, abnormal cells are found in the innermost lining of the airways. These abnormal cells may become cancer and spread into nearby normal tissue. Stage 0 is also called carcinoma in situ (localized).
- 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.
- Stage IB: One or more of the following is true:
- The tumor is larger than 3 centimeters.
- Cancer has spread to the main bronchus of the lung, and is at least 2 centimeters from the carina (where the trachea joins the bronchi).
- Cancer has spread to the innermost layer of the membrane that covers the lungs.
- The tumor partly blocks the bronchus or bronchioles and part of the lung has collapsed or developed pneumonitis (inflammation of the lung).
- 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 or smaller and cancer has spread to nearby lymph nodes on the same side of the chest as the tumor.
- Stage IIB (1):
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
- Stage IIB (2)
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, IIIC:
- Stage IV: Stage IV is divided into stages IVA and IVB.