If the white spots are flat (rather than raised or puffy), this may be
a condition called vitiligo. Vitiligo on and around the penis is
fairly common, and is not indicative of anything harmful or malignant.
"Vitiligo is a rather common skin condition affecting about 1 percent
of the world's population. Vitiligo is marked by the loss of skin
pigment, leaving patches or whole areas of the body completely white.
It affects both sexes and people of all races and all ages. The white
patches of skin are caused by the loss of cells that produce melanin
(melanocytes), which is responsible for providing skin pigment. Why
those melanocytes disappear, though, has not yet been determined."
Go Ask Alice
"Vitiligo, in which your skin can be blotchy or even very white in
areas where it loses its pigment. While vitiligo is not dangerous
(except that it predisposes you to sunburn), it can make you very
self-conscious. Vitiligo can affect skin anywhere on your body, but
the penis is an especially common location. A dermatologist or
urologist can examine your penis and tell you if you have this
condition. Unfortunately, there is no good treatment to restore the
"Vitiligo (vit-ill-eye-go) is a pigmentation disorder in which
melanocytes (the cells that make pigment) in the skin, the tissues
that line the inside of the mouth and nose and genital and rectal
areas (mucous membranes), and the retina of the eyes are destroyed. As
a result, white patches of skin appear on different parts of the body.
The hair that grows in areas affected by vitiligo may turn white.
The cause of vitiligo is not known, but doctors and researchers have
several different theories. One theory is that people develop
antibodies that destroy the melanocytes in their own bodies. Another
theory is that melanocytes destroy themselves. Finally, some people
have reported that a single event such as sunburn or emotional
distress triggered vitiligo; however, these events have not been
scientifically proven to cause vitiligo."
The MedHelp page linked above is worth reading in its entirety. It
contains quite a bit of good information about vitiligo.
Another good source of info is the American Vitiligo Research
Foundation. Here's a page of vitiligo questions and treatments:
American Vitiligo Research Foundation
Many years ago I had a close friend who had vitiligo in his genital
area. He called the white spots "nega-freckles." My friend's solution
to the problem was to dab each white spot with a bit of self-tanning
cream (the kind that gives the appearance of a suntan without the
Google search strategy:
Google Web Search: "vitiligo" + "penis"
Google Web Search: 'hypopigmentation" + "penis"
I hope this helps! Please keep in mind that Google Answers is not a
source of authoritative medical advice, and the material I've
presented should not be viewed as a diagnosis nor as a substitute for
the services of a qualified medical professional. Let me know if
anything is unclear; I'll be glad to offer further assistance before
you rate my answer.