EXTRACORPOREAL PHOTOPHERESIS OF CUTANEOUS T-CELL LYMPHOMA IS ASSOCIATED WITH REDUCTION OF PERIPHERAL CD4-LYMPHOCYTES( T)

Background: Extracorporeal photopheresis (ECP) has been successfully i ntroduced for the treatment of cutaneous T-cell lymphoma; however, the mechanism(s) of its action is (are) unknown. Objective: To investigat e the effects of ECP on the immune system of patients with cutaneous T -cell lymphoma. Methods: Clinical response and changes of lymphocyte s ubpopulations in 20 patients with cutaneous T-cell lymphoma under ECP monotherapy or combined regimens were evaluated and compared after 3, 6 and 12 ECP cycles. Results: Thirteen of 20 patients showed a greater than or equal to 50% reduction of skin lesions after 6-12 ECP cycles, An overall T-lymphocyte reduction was assessed with a balanced CD4+ T -helper and CD8+ T-suppressor cell decrease in responders. In contrast , there was a trend of CD4+ T-helper cell increase in nonresponders wh ich could result from the failure of treatment to control the natural course of the disease, The CD4+/CD8+ ratios were 1.6 at baseline and 1 .4 after 12 cycles in responders, while they increased from 1.7 to 4.1 in nonresponders, respectively (p=0.047). In addition, there was an o verall decrease in the CD57+/CD8+ T-cell subpopulation mostly due to a reduction in the responder group. Conclusion: The marked differences detected in certain T-cell subpopulations suggest an effect of ECP on peripheral T lymphocytes and, especially, on CD4+ cells.