What are the chances that mid-back pain when you sit and move certain ways is lung cancer? or does cancer cause dull constant pain, not just when sit?

Why lung cancer?: Back pain is common, lung cancer is rather uncommon, especially in a 32 year old person!. So I would think of common causes first. Most back pains are muscular or disc related and go away in 2-3 weeks. There is no special feature to back pain that points towards Lung cancer as the underlying cause.

Very, very low: Dx of lung cancer is rarely if ever based on a back pain presentation. Stop worrying yourself about that. Do consider an exam to determine the problem - but expect it to be muscular or weight related. Whatever it is, try to follow tx recommendations. If you smoke - cut down or quit and ask the Dr for ways to evaluate your lung health. It's a good way to start the New Year - living healthily!.