They've yet to come up with anything except pumping you with poisons that merely give you an extra year or two to live while you suffer humiliating side-effects.
When you ask experts about why they've never come up with a cure, their answers are always the same "Cancer isn't one disease. It's a million different diseases. It would be like you want a single cure for infections." Well, infections do have a cure: antibiotics.
Another more modern excuse from top cancer researchers is that "Cancer is an evolutionary mechanism to protect the species gene pool". So is everything else we cure, right?
It seems the billions of dollars pushed into all this research is pointless. From the outside it looks as though these researchers don't try to understand what cancer even is, they just rely on trial and error and hope they find something that works.