SHOW ME SOME DATA! TROLL
BTW, Welcome to FR. :D
Well, my ever-cordial newbie FRiend, for starters, 90% of lung cancer cases occur among smokers. Lung cancer is a preventable disease -- just as you're not likely to get HIV if you don't have sex with someone who is HIV+, you're also not likely to get lung cancer if you don't smoke. And if you do still get lung cancer even though you don't smoke (that other 10%), it's probably because you've inhaled asbestos fibers or radon or some other completely avoidable carcinogen.
Source: http://www.ctsu.ox.ac.uk/~tobacco/
So yes, lung cancer and HIV/AIDS are both avoidable diseases. So what?