PUVA therapy: current concerns in Japan

Photochemotherapy using methoxsalen in combination with long-wave ultraviol et light (PUVA) is an essential modality in the treatment of various skin d iseases. Major therapeutic regimens include oral: topical and water-deliver y methods. An adequate regimen should be chosen regarding cases of disease, extent of involvement and the age of patients. In Japan, however, treatmen t techniques and protocols have not yet been standardized. PUVA therapy may be a first choice in the early stages of mycosis fungoides and a second ch oice or an adjunctive measure in other diseases, such as psoriasis, vitilig o and atopic dermatitis, which have been disabling or resistant to conventi onal treatments. Japanese guidelines for PUVA therapy of psoriasis are bein g prepared to be produced. Risks and benefits must be weighed and the patie nt orientation is necessary to complete the treatment and also to minimize side-effects. Although possible risks for skin cancers in Japanese patients have been reported to be much lower, a careful monitoring of the patient's skin changes is recommended. While action mechanisms are not completely un derstood, recent investigations suggest that both antiproliferative and imm unomodulatory effects are involved. This review article deals with the rece nt progress in clinical and basic research on PUVA therapy, focusing on our current concerns. (C) 1999 Elsevier Science Ireland Ltd. All rights reserv ed.