Non-Small Cell Lung Cancers: Non-small cell lung cancer accounts for 80 percent of lung cancers. Up to 50 percent of non-small cell lung cancers are considered adenocarcinomas. This type of lung cancer is often seen in non-smokers and is the lung cancer type most commonly found in women. Non-small cell lung cancer usually begins in the periphery (outer parts) of the lungs, and it can be present for a long time before it is diagnosed.