The compound, Quercetin is the compound from onions and apple peels and it works proven against cancer cells. It has been tested in labs numerous times (reaction tubes ofcourse) against cancer cells. It has low-toxicity and it does not affect normal cells. In theory, it's a 100% cancer cure (I'll tell you more on request). I don't know how long it takes for effect. I would expect it to work immidiately. I don't know if it will completely demolish the cancer, hopefully yes.
It's an experimental cancer treatment. I can't guarantee you it will work and I don't know against which cancers it is (most) effective.
I can tell you it's worth trying. Considering that Quercetin is already in your diet (if you eat onions or apple peels, you eat quercetin) and it's cheap ($20) and it has low toxicity. You do have to dissolve it in the Vitamin C + water, as instructed.