Does smoking marijuana cause cancer?

Does smoking marijuana cause cancer?

David G. Ostrow (Medical Marijuana Doctor) gives expert video advice on: What are some potential side effects from using medical marijuana?; Is marijuana a gateway drug?; Does marijuana cause brain damage? and more...

In the best study to date, which is out of the very large managed care system based in California, Kaiser Permanente, there was no elevation above that for non-smokers in general of any cancers, except the possible elevation in prostate cancer among men. But it wasn't a very big elevation and its mechanism is unknown.