Lung cancer staging is used to describe the amount and extent of cancer in a patient’s body. This information helps physicians create an appropriate treatment plan and plays a role in determining a patient’s prognosis.
TNM staging for lung cancer
The most commonly used staging system for lung cancer is the TNM system from the American Joint Committee on Cancer (AJCC). It considers three key factors:
- Tumor (T) – The size of the tumor and whether or not it has invaded nearby tissues
- Lymph nodes (N) – Whether or not cancer has traveled to nearby lymph nodes
- Metastasis (M) – If and how far the cancer has spread (metastasized) to other structures in the body, such as the other lung, brain or liver
Based on this information, a patient’s lung cancer is staged from 0 to 4, with 4 being the most advanced.
Stages of non-small cell lung cancer
The stage of non-small cell lung cancer (the most common type of lung cancer) is determined at the time of diagnosis by reviewing a patient’s imaging scans. Physicians look at the images to see how large the tumor is and whether it has spread to surrounding structures in the lungs. If a biopsy was performed, the results will be considered as well. Following the TNM system guidelines, a physician will assign one of the following non-small cell lung cancer stages:
- Stage 0 – These cancers are referred to as “in situ,” meaning “in place.” The tumors have not grown into nearby tissues, and there are no signs of cancer outside the lung.
- Stage 1 – These tumors are small (less than 5 centimeters wide) and have not spread to any nearby lymph nodes.
- Stage 2 – These tumors are still small (less than 7 centimeters wide) but have started to spread to local lymph nodes or other nearby structures.
- Stage 3 – These cancers have spread to the lymph nodes in the center of the chest or other structures outside the lung.
- Stage 4 – These cancers have spread to more than one area in the other lung, the fluid surrounding the lung or additional organs elsewhere in the body.
Stages of small cell lung cancer
Small cell lung cancer—which accounts for about 15% of lung cancer cases—is also staged according to the TNM system. However, an additional staging system that labels the cancer as either limited stage or extensive stage is often used for treatment purposes.
- Limited stage – This refers to small cell lung cancer that is confined to one side of the chest, including cancer that that has not spread beyond the lung or has traveled to lymph nodes on the same side of the chest.
- Extensive stage – Most people with small cell lung cancer are diagnosed with extensive stage disease, which means cancer has spread beyond the lung and to other structures in the body, which may include the fluid surrounding the lung.
Treatment for lung cancer at Moffitt Cancer Center
Lung cancer stages help a physician determine which therapies might be most helpful for their patients. However, stages don’t take into account the fact that every patient responds differently to treatment and that an assigned cancer stage isn’t necessarily a predictor of a patient’s prognosis. Nobody understands this reality better than the multispecialty team in Moffitt Cancer Center’s Thoracic Oncology Program, where every patient receives an individualized treatment plan—regardless of the stage of their cancer. While our lung cancer specialists use evidence-based best practices to make their recommendations, we see our patients as much more than statistics, and we provide them with the tailored care they deserve.
Medically reviewed by Dr. Tawee Tanvetyanon.