Lung Cancer Stages: Stage 0 Through Stage 4
After the type of lung cancer is determined, the type is then assigned a lung cancer stage. The stage indicates how much the cancer has spread in the body (for example, to the lymph nodes or to distant organs like the brain). Stages for non-small cell lung cancers are different from small cell lung cancers. The stages listed below are taken from the National Cancer Institute’s lung cancer staging information:
Small Cell Lung Cancer Stages
Limited stage: In this form, small cell lung cancer is limited to one side of the chest, typically in the lungs and lymph nodes. About one in three people with small cell lung cancer have limited stage cancer upon the first diagnosis.
Extensive stage: This refers to small cell lung cancer that has spread throughout one lung, spread into both lungs, to lymph nodes on the other side of the chest or to other body parts. About two in three people with small cell lung cancer have extensive stage cancer upon first diagnosis.
Non-Small Cell Lung Cancer Stages
Occult (hidden) stage: In this stage, cancer cells appear in a sputum cytology exam or other test, though no tumor location can be found.
Stage 0 (carcinoma in situ): In this lung cancer stage, cancer cells are only found in the top layer of cells lining air passages and has not crept deeper into the lungs or spread beyond the air passages.
Stage I: A small lung cancer tumor (less than 3 centimeters across) is discovered, but has not spread to surrounding lung membranes, lymph nodes, or the main bronchial branches of the lungs.
Stage II: There are several ways that stage II lung cancer may be diagnosed. One is that the lung cancer has spread to lymph nodes near the lungs.
- Stage IIA: If the tumor is between 3 centimeters and 5 centimeters, the lung cancer is defined as stage IIA. Other factors can lead to this classification as well.
- Stage IIB: If the lung cancer tumor is between 5 centimeters and 7 centimeters, it is categorized as Stage IIB. Other factors can lead to this classification as well.
Stage III: As in stage II lung cancer, stage III has several definitions. One is that the lung cancer is found in both the lung and lymph nodes in the middle of the chest. Stage III lung cancer is divided into two subsets.
- Stage IIIA: This defines a lung cancer that has spread on the same side of the chest from where it started.
- Stage IIIB: This defines a lung cancer in which the cancer has spread to either the opposite side of the chest or above the collar bone.
Stage IV: This is the most advanced stage of lung cancer. The cancer can be any size, but two of these three things have happened:
- The cancer has spread to the opposite lung from where it began.
- Cancer cells have been discovered in the fluid surrounding the lung.
- Cancer cells have been discovered in the fluid surrounding the heart.