How do I know if I have lung cancer?

 Early detection of lung cancer is generally difficult because typically the cancer itself will not accompany any initial symptoms. Often the cancer is detected on routine chest scans or CT scans for other reasons. The only way to know for sure is to have a biopsy performed, in which tiny tissue from the area is removed and tested for cancer cells, while at the same time determining if the cancer is benign or malignant.