Caveat: I am not qualified to evaluate any scientific studies.

I would never dispute the fact that marijuana is being used to successfully treat more and more conditions. Given time and study medical professionals, with help from scientists, will reach a consensus on cannabis and cancer. When they do, the PDQ will reflect that. Why rush it? Thankfully, all Colorado cancer patients are eligible, no questions asked: it's proper for government scientists to wait for consensus when writing summaries, but in the meantime, tumor patients who want to pursue treatment with cannabis have immediate safe access. That seems like wisdom to me.