Have shoulder aches for a few months . could it be lung cancer? shoulder isn't painful. i'm a non smoker

Low on diff dx: In medicine, we often think of many possibilities for specific symptoms, called a "differential diagnosis list" and lung cancer for shoulder aches would be way down on the list, if even on the list at all. I would see a dr and get the shoulder evaluated, properly diagnosed and then the best treatment would occur. Good luck.

Unlikely but: Given that you are a non-smoker it is unlikely that your pain is due to lung cancer. However, we definitely see lung cancer in never smokers. I advice that you see your primary care physician for a physical exam. Most likely it will be something else but it is better just to be seen by pcp.