I guess this dark patch has been there for awhile, but it seems to be getting slightly bigger over the past 6 months. I just turned 40 and I'm wondering if its cancer, std or just a pigmented small piece of my penis shaft. It bothers me because I don't know what it is. If you look very closely at it, it does seem to have some small bumps on it and when you pinch the soft penis skin together it seems to be slightly raised. Definately an eraser head sized, pigmented darker color, mole-looking patch that I want checked out.

Any suggestions or anyone with simliar description.
thx!