Yes, melanoma can grow like wildfire. It killed my dad (who was the owner of a longtime interstate business and worked mostly outside) in just over 4 months. He discovered a lump in his chest in September (not last year). It was in the area of a small protruding injury he thought he had gotten while leaning over one of his machines so he had put a bandage on it. He had it checked by his dr later that month and it was determined to be malignant melanoma. A large tumor which had grown deep into his chest was removed and he was completely healed from surgery by the first of December. He had a cat scan and everything was clear so he went back to work. By the third week of January, he was having trouble breathing and was admitted to the hospital with pneumonia. By the end of January, he was dead, due to the rapid spread of melanoma to his lungs. By the time I arrived at his bedside, he had been in intensive care on a bipap machine for 3 days at which time his doctor gave him a week to live. He lived 5 days after that diagnosis.
Melanoma kills by spreading through the cancer stages as a rapid fire rate (before many people detect any abnormalities concerning enough to get them to a doctor):
My dad was neither fair-skinned nor light-haired, tolerated the sun well (or so he thought) and was a self-made man with incredible business smarts. At 73, he was still working only because he enjoyed it. This could happen to anyone of any age (but usually to those over 50 who may have endured many years of sun exposure) who isn’t paying close attention to changes and abnormalities on/in their body.
I spent a lot of time in the sun when I was younger (mostly boating/waterskiing) but I haven’t done so for about 15 years. When I must be out there in the middle of the day, I wear 50+ sunscreen and 70-100 on my face and I do all my yardwork between 4 pm and 8 pm (depending upon season).