Money spent on cancer research tends to have wide-ranging implications outside of cancer. It produces a ton of understanding about gene regulation, cellular integrity, etc. Personally I would prefer the money not be earmarked for cancer research, but for understanding evolution, growth, and development of organisms composed of cells, in a way that those discoveries led to treatments. But the way it works right now has also had a huge benefit across many non-cancer research areas.
I suspect that the amount spent is still far too large for the direct results.