Is there any studies on cancer from people who smoked there own tobacco and not store bought products ?
The closest you will find to answering this are studies done with cigar smokers. It's not "grow your own tobacco" but its about as chemical free as you are going to get. All cause mortality decreases in people that smoke 1 to 2 cigars per day. This is not the same for cigarettes. But then again, you inhale cigarette smoke along with hundreds of toxic chemicals. Pipe tobacco is on par with cigarettes because they add tons of flavoring agents to tobacco smoke.
Another interesting fact about cigar smokers is that emphysema increases with cigar usage(starting about about 3-5 cigars) until you smoke about 6-7 per day and then it drops like a rock. Why is that? I don't know but if I was a researcher I would love to find out. And here is the problem I have with society. We have so demonized tobacco that we refuse to investigate any possible benefits from it. True, commercial cigarettes increase your risk of cancer, but cigars lower your risk of death from all causes... so let's fund some studies.. of I forgot... there's NOTHING good about tobacco!