A 57-year old Hispanic man had discolored patches on the upper and lower limbs for years. Most of the patches were situated on the forearms and the legs, those at the former site being hyperpigmented and those at the latter site both hyper- and hypopigmented, the ones with little pigment being nummular. A biopsy of a representative lesion was performed.

The findings by microscopy are those of mycosis fungoides, to wit, lymphocytes around venules of the superficial plexus, scattered in some dermal papillae, aligned as solitary units in loci of the epidermal basal layer and disposed in near clusters in foci of the spinous zone in company with paltry spongiosis, above which was a tad of parakeratosis.