Skin cancer has become so common in recent years I think most people could name at least a few of the signs to look for when wondering if a "spot" is cancerous or not. But the ABCD rule -- asymmetry, border irregularity, color irregularity, and large diameter -- has actually become somewhat dangerous. How is that possible? A study out of Australia shows that often melanomas (the fastest growing and most deadly form of skin cancer) do not have any of the ABCD characteristics, and actually go so far as to be completely opposite (regular borders, even color, symmetrical, etc). They are, though, usually itchy or bleeding and elevated.

So what's the best way to be safe? Have any growing or changing skin lesion checked by a professional asap, whether it fits any symptom set or not.