The stage of a cancer is basically how far the cancer has spread — if you have cancer, your doctor will probably tell you the number stage of your disease. Treatment is often decided according to the stage of a cancer.
Small cell lung cancer can be divided into two stages: limited diseases and extensive diseases. Limited disease means that the cancer is only seen in one lung, in nearby lymph nodes, and/or in fluid around the lung. Extensive disease means that the cancer has spread outside the lung to the chest and/or other parts of the body.
Staging for non-small cell lung cancer is a little more complicated. There are four stages and several subgroups.
- Stage 1: The cancer is localized.
- Stage 1A: The tumor is small (less than 3cm across).
- Stage 1B: Includes cancers that are larger or cancers that have grown into the main airway. Also includes cancers that have grown into the inner covering of the lung or caused a partial lung collapse.
- Stage 2: The cancer has reached the lymph nodes at the top of the lung.
- Stage 2A: The cancer is small, but has spread to the lymph nodes closest to the affected lung.
- Stage 2B: The cancer is larger and has spread to the lymph nodes closest to the affected lung OR there is no cancer in the lymph nodes but it has spread into the chest wall, the outer covering of the lung, the diaphragm, or the outer covering of the heart.
- Stage 3: The cancer has spread into the chest wall.
- Stage 3A: The cancer has spread farther away from the affected lung but is still on the same side of the body OR there is cancer only in the lymph nodes nearest to the affected lung but the cancer has also spread to the chest wall, the covering of the lung, or the middle of the chest.
- Stage 3B: The cancer has spread to the other side of the chest or above the collar bone OR there is more than one tumor in the lung OR the tumor has grown into another structure in the chest like the heart, the windpipe, the esophagus, or a blood vessel OR there is fluid collecting around your lungs that contains cancer cells.
- Stage 4: The cancer has spread to another part of the body from where it started, like the other lung, other organs, or your bones.