Interesting that you point to that, because in my own mind, when I want to think about the most spectacular achievements of humanity, my two first candidates are : "we walked on the moon" and "we eradicated smallpox". They are on pair to me, the glorious achievements of human minds overpowering Azathoth (gladly, Azathoth isn't fighting back).

And a cure for cancer, along side with going to Mars or doing a permanent base on the Moon, would be the next step of those two achievements.