Cancer causes changes in cells that are otherwise healthy. The cells grow too quickly, without dying off. Healthy cells in the body usually die at a certain stage in their life cycle, thereby preventing a buildup of too many cells. In cancer, however, cells continue to grow and multiply. As a result, tumors develop. The two main types of lung carcinoma are small-cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC), depending on how they appear under a microscope. NSCLC is more common than SCLC
同步放化療 .