I definitely think young people who tan should take skin cancer more seriously. My dad just recently got skin cancer from years of being outside on the farm, and although it's not the most life threatening skin cancers, it could easily become melanoma.
If you want to look tan, you can get spray tans. I'm guilty of not wearing sun screen all the time in the sun, since I don't burn easily, but since this happened to my dad I'm going to.

Great to hear your friends cancer didn't spread, I hope she will be completely cancer free soon.