Lung Cancer Home > Lung Cancer Stages
Stages for non-small cell lung cancer are divided into the following stages:
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 assessed.
In stage 0 lung cancer (carcinoma in situ), cancer is limited to the lung and is found only in a few layers of cells. It has not grown through the top lining of the lung.
In stage I lung cancer (or stage 1 lung cancer), the cancer is in the lung only, with normal tissue around the tumor. Stage I is divided into stages IA and IB, based on the size of the tumor.
In stage II lung cancer (or stage 2 lung cancer), cancer has spread to nearby lymph nodes or to the chest wall (the ribs and muscles that make up the area of the body between the neck and the abdomen), the diaphragm (the thin muscle below the lungs and heart that separates the chest from the abdomen), the mediastinal pleura (the thin membrane that covers the outside of the lungs in the area near the heart), or the parietal pericardium (the outer layer of tissue that surrounds the heart). Stage II is divided into stage IIA and stage IIB, based on the size of the tumor and whether it has spread to the lymph nodes.
In stage III lung cancer (or stage 3 lung cancer), cancer has either:
- Spread to the lymph nodes in the mediastinum (the middle area between the lungs that contains the heart, major blood vessels, and other structures)
- Spread to the lymph nodes on the opposite side of the chest or in the lower neck.
Stage III is divided into stage IIIA (which is sometimes treated with surgery) and stage IIIB (which is rarely treated with surgery).