As ultra athletes we tend to spend a great deal of time outdoors whether training or racing.
We need to be very much aware of what we can be susceptible to as we enjoy the freedom of walking (or, running, hiking, strolling, etc) through the great outdoors.
Melanoma is a deadly form of skin cancer, which generally starts from a mole that is changing quite rapidly anywhere on the body. After all, Bob Marley died from a melanoma under the nail on the big toe of his right foot!
So if you have a mole that's 'doing things': enlarging, changing colour (especially black or mottled), thickening, ragged outlines etc., then go to the doctor. NOW. Not tomorrow: NOW, and you might just have saved your life.
It's one of the diseases that particularly affects people with an outdoor lifestyle: runners, walkers, swimmers, gardeners etc. It affected 1 in 1,500 in the 1930s: now it affects 1 in 50, and unless diagnosed early there is a very high death rate, up to 25%.