Ultraviolet B irradiation - A new therapeutic concept for the management of oral manifestations of graft-versus-host disease

Ultraviolet irradiation inhibits the proliferative responses of lymphoid ce lls to mitogens and alloantigens by inactivation of T lymphocytes and antig en-presenting cells. Its immunosuppressive capacity led to the introduction of UV irradiation into clinical practice for the treatment or dermatologic manifestations of chronic graft-versus-host disease. The cumulative experi ence with psoralen-UV-A rays in the treatment of cutaneous and oral graft-v enus-host disease was the incentive for the application of oral UV-B rays i n 2 patients with oral graft-versus-host disease signs and symptoms after a llogeneic marrow transplantation. Intraoral UV-B irradiation (0.02 mJ/cm(2) ) was administered 2 or 3 times per week on an ambulatory basis; the dose w as increased by 0.02 mJ/cm(2) every fourth session. Both patients responded early and satisfactorily, displaying only minimal side effects at a relati vely low cumulative dose. Intraoral UV-B proved a valuable modality in the treatment of resistant chronic oral graft-versus-host disease.