How long does someone survive with non-small cell lung cancer?

Depends on stage: The long term prognosis of lung cancer depends on the stage of the cancer. The stage (1-4) depends on the size of the tumor and whether it has spread outside of the lung to lymph nodes, the lining of the chest wall (pleura) or other organs (liver, brain, etc). Some of this information may be determined by x ray test (ct scan, pet scan) and some may require biopsies to determine.

Depends on Stage: The answer to that question depends greatly on how advanced the cancer is when it is diagnosed. That, in turn, depends on how big the tumor is, where it is located, whether it has spread locally or all over the body. Generally, the earlier you catch the cancer, the longer the survival is. That is not a 100% "take it to the bank" rule, but it is a general pattern. A number of tests find out stage.