How common is lung cancer in non smokers? And is it true only a certain type of lung cancer is genetic? And if so which type?

Scientists and. Lung cancer experts are gaga about this: women, non-smoking asians have epidermal growth factor receptor defects maybe 5% of lung cancers, and alk is another molecular detected marker. At the extreme this is about 15%, more likely 5%. Wonderful science. Associated with adenocarcinoma phenotype, not squamous or small cell. It's the tobacco that's the low hanging fruit.
Lung cancer. Of all lung cancers 97% are smoking related. 3 % in non smokers. Regd the genetic basis of lung cancer, to the best of my knowledge, there is no genetic variant. Sonetimes we see several cases in families but still primarily it is smoking associated.
See below. Most lung cancer patients are smokers or former smokers; however, 15 % of patients with lung cancer have never smoked. The biology of lung cancer in never smokers is strikingly different; mostly adenocarcinomas and are oncogene addicted (egfr, alk and ros positive); it is important to see a lung cancer expert to be able to explore potential personalized treatment in these situations.
Lower. There are still some alveolar cell and adenocarcinomas in non smokers but less squamous. Some nonsmokers did have second hand or other exposures.