I have dark patches on my lower leg that I thought was do to using my legs to realign 4x8 sheets of melamine, which I incurred scrapes and cuts do to the sharp edges. I took care of that, but then the dark patches came, thinking it was the result of using my legs for leverage to align the sheets. They seem to get better and sometimes worse. They are located in the shin area. Is this a sign of skin cancer or organ disease of some type. Thank you for a response. I have a family doctor who I like, I m afraid to see him