Long-term safety of trioxsalen bath PUVA treatment: an 8-year follow-up of 149 psoriasis patients.

A thorough clinical follow-up study with regard to the occurrence of degenerative skin changes and cutaneous carcinomas was undertaken in 1982 in 149 patients with moderate to severe psoriasis treated with PUVA baths (trioxsalen + UVA). The PUVA treatment had been commenced between 1974 and 1978. With trioxsalen baths a high sensitivity to UVA is obtained. The initial UVA dosage is therefore as low as 0.04-0.08 J/cm2 and in the majority of the patients the maximum daily dose was about 1.0 J/cm2. The accumulated UVA dosage was low. Thus 89% of the patients had received less than 50 J/cm2 in 5-8 years of bath PUVA treatment. No degenerative skin changes were found on PUVA-exposed skin that were not also seen on the facial skin not exposed to PUVA. Two patients showed mild mottling of exposed skin. Otherwise no PUVA-related degenerative changes were observed. No carcinomas were found on bath PUVA-treated skin.