Photochemotherapy in cutaneous T cell lymphoma and parapsoriasis en plaques. Long-term follow-up in forty-three patients

Abstract

Forty-three patients with clinical plaque- and tumor-stage mycosis fungoides, the erythrodermic/Sézary syndrome variant of mycosis fungoides, and parapsoriasis en plaques were treated with oral psoralens and ultraviolet A (PUVA). Pretreatment skin biopsies, evaluated by light microscopy, revealed seventeen diagnostic, seventeen suggestive, and nine nonspecific specimens. Clinical and histologic parameters were followed for an average of 38.4 months (range, 4-67 months). Twenty-five patients had complete clearing, and fourteen did not respond. Most patients in the complete-response group had either plaque lesions of mycosis fungoides or parapsoriasis en plaques prior to PUVA. Most patients in the no-response group had either tumor lesions or the erythrodermic/Sézary mycosis fungoides at the start of PUVA. In the no-response group the treatment modalities used prior to PUVA were twice the number used in the complete-response group. Patients in the complete-response group had clearing of their lesions after an average PUVA dose of 117 joules/cm2. Relapse occurred in seventeen patients after an average remission time of 6.3 months and responded to additional PUVA. Patients whose skin remained clear after the first course of PUVA continued to have clear skin for up to 58 months, with an average complete remission of 29.5 months by the end of the study period. Histologic evaluation before PUVA and at clearing revealed a definite trend toward a normal microscopic picture, but at least a mild inflammatory infiltrate usually persisted. At the end of the study period, the lesions of ten patients had entirely cleared for an average of 44 months, the lesions of five had cleared during a second course of PUVA, five had stable limited-plaque disease while receiving maintenance PUVA, eleven were undergoing electron beam radiation therapy or chemotherapy for progressive disease, ten had died, and two patients were lost to follow-up. Therefore, in the early stage of mycosis fungoides, PUVA may induce significant disease-free intervals. Prior treatment with a variety of modalities, the patient's age, and/or the duration of disease may affect response to PUVA.