Staging is the process by which your cancer specialists determine how far your cancer has spread (or its stage).

Non-small cell lung cancer is divided into four stages. Stage 1 indicates that the tumor is limited to a small area within the lung; this is early stage. Stage 4 indicates that the cancer has spread through the bloodstream to areas in the body distant to where the cancer started. As the stage number increases, the prognosis for the patient worsens, because the tumor is harder to cure. Unfortunately, the majority of patients with lung cancer do not seek medical attention until the disease has reached stage 3 and 4. This is because lung cancer typically has no symptoms until it has reached this stage.

Small cell lung cancer is staged using the terms “limited” or “extensive” disease. Limited disease is when the tumor is limited to the chest and can be contained within a radiation port. Extensive disease indicates that the cancer has spread beyond this port or to distant areas in the body.

It is important for doctors to put patients into the proper stage. In this way, they can tell patients what the best treatment is for them. Stages 3 and 4 usually require treatments that affect the whole body. It is also important to classify patients into these stages so doctors can figure out whether new treatment methods are working. If patient groups weren't made uniform by this method, there would be no way of studying the problem scientifically.

Doctors look at three major items when determining the stage; T-Tumor growth and extent; N-Lymph Node involvement; M-distant Metastasis (spread). Often your physicians gather this information while seeking confirmation of the diagnosis. You may undergo additional tests to assist with staging. These may include a CT scan, MRI, bone scan or PET scan.