Extracorporeal photochemotherapy in the treatment of severe graft-versus-host disease

Advances in posttransplant immunosuppression have to the present not been a ble to prevent the development of graft-versus-host disease (GVHD) in patie nts given related or unrelated stem cell grafts for cure of hematologic dis eases. Patients with GVHD not responding to first line therapy with cortico steroids remain at high risk of death due to severe infections or organ fai lure. Extracorporeal exposure of peripheral blood mononuclear cells to the photosensitizing agent 8-methoxypsoralen and ultraviolet A radiation has be en shown to be effective in treatment of selected T-cell mediated diseases, including cutaneous T-cell lymphoma and rejection after organ transplantat ion. Extracorporeal photochemotherapy (ECP) is also a safe and efficacious adjunct therapy for both acute and chronic extensive GVHD with skin and vis ceral involvement and resistance to conventional immunosuppressive therapy. A multicenter randomized study should help define the impact of ECP in the treatment of GVHD and overall survival of these patients.