Photochemotherapy of Cutaneous Graft-versus-Host Disease May Reduce Concomitant Visceral Disease

Background: Photochemotherapy may be used to treat cutaneous graft-versus-host disease (GvHD). Animal models show that in the days after photochemotherapy and antigen provocation, cells with an antigen-specific suppressive phenotype are elicited in the lymphoid organs. In GvHD, host antigens are present not only in the skin treated by photo chemotherapy but also in the visceral tissues. Objective:The aim of this paper was to evaluate the effect on visceral acute GvHD (aGvHD) of photochemotherapy of the skin. Methods: We retrospectively evaluated 33 patients with aGvHD of the skin, the liver, and/or the gastrointestinal tract treated with photochemotherapy for their aGvHD of the skin and did a long-term follow-up of 10 years on survival. Results: The complete response (CR) to photochemotherapy was 39%, the complete and partial response was 64% and the 6-month survival was 64%. Total body irradiation (TBI) before hematopoietic stem cell transplantation predisposed for CR of aGvHD of the liver and the gastrointestinal tract (p = 0.045). In the TBI group, the accumulated dose (numbers of treatments) for CR of visceral aGvHD increased with the body surface area affected by disease, from 8 (min max:5-14) for skin disease stage 1 to 10.5 (6-33) for stage 2 and 13 (11-21) for stage 3 (p = 0.04). Skin disease stage 1 showed a trend to be associated with CR in visceral disease at 28, 56, and 100 days (p = 0.07). Overall CR in visceral disease predicted a better 10-year overall survival (p = 0.0036). Finally, after TBI aGvHD of the gastrointestinal tract without anti-thymocyte globulin (ATG), clearance of T cells and dendritic cells responded better than aGvHD of the liver and aGvHD of the gastrointestinal tract with ATG (p = 0.01). Conclusion: Photochemotherapy after ionizing irradiation regulates the cell-mediated immunity in the viscera, and the systemic efficacy increases when the skin itself is less affected by disease. ATG modulates the regulatory effect of the gastrointestinal tract. (C) 2016 S. Karger AG, Basel