First of all, a bit of a fact check on the source. Winthrope University is a very new state college. It has no medical school....it does have a very recently opened hospital. Certainly not anywhere near the top tier of research institutions. Nor is Dr. Katz one of the top research scientists in the field. AND prostate cancer is NOT bladder cancer.
It is never a bad idea to have a really good, healthy diet and life style. However, whatever has gone wrong in the basic cells that cause cancer (bladder or any other) probably started many many years ago. If a "supplement" or an herbal concoction were to do any good it would have to be used then. But there is no scientific proof that these have any beneficial effects at any time. By the time the cancer has started, long before it becomes obvious, it is too late. Herbs and vitamins are not going to reverse it.
As I mentioned, a good healthy diet and lots of fluids cannot hurt and may even help the body fight off the cancer. The better shape you are in the better prepared your body is to fight back.
IMHO, you would be wasting your money.
Sara Anne