Extracorporeal photochemotherapy is a modality that has been established for the management of cutaneous Tcell lymphoma. In this treatment method leukocyteenriched peripheral blood is exposed to ultraviolet-A in an extracorporeal system in the presence of psoralen. Today extracorporeal photochemotherapy is the treatment of choice especially for Sezary syndrome, in which the circulating phase of the cutaneous T-cell lymphoma dominates the clinical picture.