Depigmented patches on forearms

Case #1

A man, aged 25 years, presents with patchy areas of depigmentation on his forearm, umbilicus, and groin. The centers of the lesions are hypopigmented, and the borders are hyperpigmented. The patient states that, initially, the lesions had been expanding but following that period, the lesions did not increase in size for several years. Upon further questioning, the patient admits ...