Non-small cell lung cancer (NSCLC) is a type of lung cancer that originates from the cells lining the bronchi and alveoli (the small air sacs in the lungs). It is called "non-small cell" because the cancer cells are larger than the small cell lung cancer cells. Non-small cell lung cancer (NSCLC) is caused by changes or mutations in the DNA of lung cells. These mutations can occur in normal lung cells to grow and divide uncontrollably, leading to the formation of a tumour.
