Q: As a child my penis had a fair colour just like the rest of my body. After the age of 20, my penis glans and scrotum became a fairly rich tanned colour. I assumed this was normal and didn't worry about it. Then at the age of 40, suddenly the area of my inner thighs started becoming dark as my penis. Is this normal for some people? Or is it some skin pigmentation? It did get itchy around the age of 40, but that went away. I am not sure if that correlates with the discoloration or is a coincidence. I had a skin scrape and there is apparently nothing fungal down there. Is there a name for darkening of the penis?

A:The changes in the colour of skin of genitalia from puberty onward is just normal. The groin area pigmentation may follow tinea cruris, friction of undergarments and above 40s due to acanthosis nigricans. Acanthosis nigricans may have association with obesity, or endocrine disorders like diabetes mellitus, rarely due to underlying malignancy.