i have big black patch on left hand on upper part the same on left thigh at middle part. it was not my birth mark but when i was 5 yrs old it started with a small pigment and spread to large extent. different doctors have different views,,,,,some say its incurable,its GOD s gift...some say it can be treated... some say its blue skin disorder . till now there is no such ill effect other than pimples on patched hand. could u tell what is it? i can send u my sample pic if needed.....