when you said comes and goes,,, that is already a sign that is not a Skin cancer,,, Skin cancer Grows and are different what you described. there are only 3 types of skin cancer, Melanoma which is the most Aggressive one and 2 carcinomas which are not as aggressive as melanoma, and they do grow and don't disappear like yours,, so keep positive attitude and pray,,,
Hi, you may want to take a look at the related discussions listed alongside your post. Only your Dr can tell, but unless they've uncovered something, doubt it's skin cancer but I'm not a Dr.