The foundational problem with cancer is that multicellular organisms rely on tight control of the cell division cycle and there are hundreds of ways that can go off kilter. The record of understanding and treatment is impressive, certainly, but the correct mental model is more ‘think of all the problems that can go wrong with a rocket launch - from contaminated fuel to software glitches’ than ‘here’s a list of cancers of different cell and organ types’.

Just as attacking such problems with rocket launches involves hundreds of different approaches, that’s the situation for cancer. I’d also point out that this is why it was really not trivial to identify microbial and viral causes of disease in the 19th century - especially since we now know that certain kinds of infectious disease can themselves result in cancer initiation. It’s definitely a hard set of problems.

I would also add, there was a concerted effort by industry to promote ‘inherent genetic malfunction’ as the cause of cancer in the late 1990s and early 2000s, but the reality is that exposure to industrial carcinogens tracks closely with a wide variety of cancers (skin, digestive tract, etc.). This was a very deceptive and dishonest approach to avoiding regulation.