white spots/patches on glans??

i have these weird white spots/patches on the head of my penis. I'm in my late twenties and i've had this problem for many years now. I haven't been sexually active for a year so i dont think it's STD. i have no problem retracting my foreskin whatsoever and it doesn't hurt so it haven't bothered me at all. It just looks weird and.. discolored. I've noticed the discoloration has very slowly gotten worse and it doesn't seem to go away, any ideas on what it could be??

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There could be a relatively simple explanation for this such as Vitiligo . However, I would suggest a cautious approach, as, I know from bitter personal experience that if what turns out to be a severe skin condition develops from this it is much more difficult to deal with the longer it is left untreated.
Therefore get your GP / Family Doctor to check this for you, go to a Dermatologist or GUM Clinic at a General Hospital near you when you are able to make an appointment