Most lung cancers are classified as non-small cell lung cancer (NSCLC). About half of these are squamous cell carcinomas (SCC). SCC is sometimes called epidermoid carcinoma is more prevalent in men and arises in the lining of the large air passageways, or bronchi. Another common type of NSCLC is adenocarcinoma, which occurs at the outer edges of the lung. A small percentage of NSCLC are large-cell carcinomas, which usually develop in the smaller bronchi. Non-small cell lung cancer that begins at the top of the lung sometimes spreads to the nerves and blood vessels leading to the arm.
All three subtypes of NSCLC develop differently. Treatment are often based on the location of the particular cancer and its rate of spread.
About one in four malignancies involving the lungs are diagnosed as small cell lung cancer (SCLC). There are several types of SCLC or oat cell cancer, including a mix of small cell and other cell types. These cancers grow rapidly – doubling in cell number about every 30 days—and spread quickly to lymph nodes and other organs than the non-small cell type.