why elephants rarely get cancer?

Here's a more interesting question: Why does cancer never get cancer??

I know, mind blown.

Interesting topic, and at the end I kinda felt you stopped in the middle of it, like a cliffhanger.

Evolutionarily speaking, I would indeed expect larger animals and longer-lived animals to have less cancer, just as I would expect taller buildings to have better earthquake and wind resistance tricks: it's a problem they have to solve in the process of getting bigger/taller/longer-lived.