How Can Penis Spots With Blotching Be Treated?

I have a blotchy section of brown spots on the head of my penis, some big some small, all less then a centimeter in diameter. They appeared some time ago, maybe 2 years ago, but have only recently become visible enough for me to worry and be embarrassed. They are less visible when the penis is erect but bother me nonetheless. I just want to first know what it is & 2nd know what steps to take if anything can be done to remove or at least lessen their appearance.