I think that's an excellent observation. Some published studies suggest, exactly as you've highlighted, that the risk of getting lung cancer in never-smoking women is twice that in never-smoking men. To date there is no conclusive evidence as to why that is. There have been some questions about estrogen and the potential of estrogen and second-hand smoke but nothing conclusive.
We do know that in patients who were never smokers, we are more likely to detect abnormalities within the cancer itself, driver genes, genes that have become abnormal and that drive cancer and then are more susceptible to therapy that targets that particular genetic abnormality. We have seen that, and there are particular kinds of abnormalities that are more common in women, such as a special mutation called the epidermal growth factor receptor.
So we don't know why, but we do see this in clinical practice.