Oral photochemotherapy in lichen planus (LP) and mycosis fungoides (MF): ultrastructural modifications of the infiltrating cells.

Six patients (5 with mycosis fungoides and 1 with lichen planus) treated with PUVA, were subjected to biopsy of lesional skin before and during oral photochemotherapy. Ultrastructurally, a reduction in the density of cellular infiltrate was observed in the superficial dermis. In the same areas, necrotic cellular changes were observed. PUVA therapy exercises its beneficial effect by direct destruction of these cells.