A 50-year-old white woman had widespread hypopigmented macules, some of them having become confluent, especially on the upper and lower extremities. The lesions were asymptomatic and no scales could be noted. She stated that the lesions had been present for one year. A biopsy was taken of a hypopigmented macule.

The findings histopathologically were as follows: the cornified layer was normal, a few lymphocytes were present in the lower part of the surface epidermis in association there with but a tad of spongiosis, and some lymphocytes were noticeable around venules of the superficial plexus. The patient was thought originally to have "hypopigmented mycosis fungoides" on the basis of both clinical and histopathologic attributes. When we saw the patient in consultation, it was our judgment that, clinically and histopathologically, the diagnosis was pityriasis alba and not mycosis fungoides. In the ensuing two years, the lesions had disappeared largely, a phenomenon that the patient attributed to the effects of sunbathing.