The stage of a cancer indicates the extent to which a cancer has grown and spread in the body. Staging involves evaluation of a cancer’s size and its infiltration of surrounding tissue as well as the presence of metastases to lymph nodes and other organs. X-rays, CT scans, magnetic resonance imaging (MRI), positron emission tomography (PET), and bone scans are some of the tools available to identify and stage cases of lung cancer.
In general, the four main stages of lung cancer correspond to the following symptoms:
Stage I: The cancer is confined to the lung and is made up of fairly small tumor(s).
Stage II: Tumors have grown larger, reached the outer linings of the lung, or have spread to nearby lymph nodes.
Stage III: The tumors at this stage generally have either infiltrated organs near the lungs or have spread to more distant lymph nodes.
Stage IV: The cancer has spread from the lung to lymph nodes outside of the chest, fluid surrounding the heart and lungs, or other areas of the body.