> We should activate the natural inmune defences instead of extremely invasive chemotherapy.

Yeah, it's a shame researchers don't work on immunotherapies for cancer, I bet they could do some nifty shit with engineered t-cells.

Is there a pattern to these increases? Is it because so many other diseases have been prevented or cured that it causes more people to live long enough to get some form of cancer?

Yep. And for the smashed to pulp extremities I would suggest a fast regrowth of an arm or a leg, preferably in a week or so.

More seriously: cancer is no joke and so are the treatments.