PUVA treatment of erythrodermic and plaque type mycosis fungoides.

Five patients with plaque type mycosis fungoides (MF) and five patients with erythrodermic MF responded favorably to oral psoralen photochemotherapy (PUVA). The mean total UVA irradiation dose was less for erythrodermic than for plaque type MF, but the mean number of treatments to achieve clearing was greater in the erythrodermic patients. Histologic examination at clearing revealed persistence of an inflammatory infiltrate in the lower dermis in most cases. Subsequent recurrent lesions in five patients revealed a more extensive dermal inflammatory infiltrate, although findings were not always diagnostic of MF due to a lack of epidermal involvement. Resumption of more intensive PUVA therapy again resulted in clinical clearing in all five patients. The follow-up period for six patients who received long-term PUVA maintenance ranged from 1 1/2 to 3 1/2 years. During PUVA therapy, five of ten patients developed epithelial malignancies or premalignancies, and one patient developed a malignant fibrous histiocytoma. Most of these patients had received prior treatment with electron beam and topical nitrogen mustard.