dunno man, just had melanoma removed from my ear and if it had moved to my lymph nodes I had a 50% chance of dying within 5 years. thankfully it didn't but it was caused by sun damage incurred in my youth. I'll be wearing sunscreen and mostly avoiding direct sunlight.
It has a lot to do with the individual's makeup. My mom came from a pale lineage and had the same story as the parent comment - except for the luck part. Melanoma was common in her family and was tightly tied to excessive time in the sun as children.
