Long-term photochemotherapy: histopathological and immunofluorescence observations in 243 patients

Skin biopsies of 243 patients treated with photochemotherapy (PUVA) for 1--4 years were examined histologically. Two hundred and six patients were examined retrospectively after total cumulative UV-A doses of 579 . 6 +/- 598 . 0 J/cm2 (mean +/- s.d.). An eosinophilic homogenization and a reduction of elastic fibres at the dermo--epidermal junction, and an increase of dermal macrophages were found as possible abnormalities. However, except for the increase of melanophages there was no statistically significant correlation between the incidence of these changes, the total UV-A dose applied and the skin type of the patients. Neither were such correlations found in thirty-seven patients biopsies twice after 394 . 8 +/- 267 . 6 J/cm2 and 808 . 5 +/- 458 . 9 J/cm2 (mean +/- s.d.), respectively. Studies with direct immunofluorescence techniques revealed no immunoglobulin deposits in PUVA treated skin in fifty-six patients after 469 . 2 +/- 370 . 2 J/cm2; antinuclear antibodies were observed in 4 . 6% of 129 patients after 169 J/cm2 (mean); in 11% of fifty-three patients reexamined after 381 J/cm2 (mean) and in 13 . 6% of twenty-two patients reexamined a second time after 643 J/cm2 (mean). Thirteen out of a total of 572 patients developed a peculiar mottling of skin in areas previously overdosed by PUVA. Subepidermal homogenization and reduction of elastic fibres were found in 45% of the patients, indicating that these changes indeed are a consequence of PUVA. Nuclear and cellular irregularities were found in 45% of the biopsies and 63% showed a disturbed epidermal architecture, but no carcinomas were observed. PUVA-induced mottling was reversible in 31%, partially reversible in 15%, but continued to be present in 54%.