Analysis of clinical outcome and survival in pediatric patients undergoing extracorporeal photopheresis for the treatment of steroid-refractory GVHD.

Extracorporeal photopheresis (ECP) has been used for treatment of steroid-refractory graft-versus-host disease (GVHD) with encouraging results. However, only a few pediatric centers have experienced with ECP, mainly by technical difficulties of leukapheresis in children. We retrospectively analyzed 27 patients treated during 5 years with ECP for steroid-refractory acute and chronic GVHD. We performed an "off-line" approach using a continuous flow cell separator (Cobe Spectra) and a Ultraviolet A irradiator (UVAMATIC). Among acute GVHD patients, 11 of 21 obtained a complete remission (CR) and another 8 reached partial remission. In the chronic GVHD group, 3 patients obtained CR and another 2 were in partial remission. Disease-free survival probability was 43±9% in the whole group. The only variable that impacts on disease-free survival on multivariate analysis was achieving CR with ECP. We also found a better CD4/CD8 ratio after ECP. In detail, among CD4 lymphocyte population, an increase in the effector memory and T-regulatory population was found. We may conclude that ECP is a safe and effective steroid-refractory GVHD treatment using the ex-vivo collection method, even in small children. Clinical response favorably impacts on long-term survival and seems to be associated with peripheral blood lymphocyte subset changes generating peripheral tolerance.