Some cancers now have a 100% cure rate if they're caught early enough, Grumpy, which is certainly a big improvement on the way things were not so many years ago. So progress is definitely being made.
At one time it would have seemed impossible to rid the world of smallpox but it has now been achieved. Cancer is more difficult to deal with because
(a) it's not really a single disease but a big collection of diseases with similar characteristics ; and
(b) there's usually no obvious external agent, such as a virus or bacterium, involved in its development. (However it is now recognised that some viruses, such as Epstein-Barr, cause cancer).
There are plenty of ongoing trials for the treatments of cancer, which will hopefully lead to things getting better in the future. (I ought to know because I'm taking part in one!)