Chronic graft-versus-host disease.

Chronic graft-versus-host disease is the most common late, non-relapse complication of transplantation yet it is also one of the least studied. It is the primary cause of morbidity and mortality of long-term survivors of allogeneic bone marrow transplants. Like acute graft-versus-host disease, it does have a strong antitumor effect. The recent National Institutes of Health sponsored Chronic Graft-versus-Host Disease Consensus Conference has proposed new criteria for diagnosis and staging, pathology, biomarkers, response and supportive care. New understanding of the pathophysiology of chronic graft-versus-host disease (i.e. the role of B cells) is already having an impact on therapy. Novel agents such as pentostatin, mycophenolate mofetil, rituximab, extracorporeal photochemotherapy, etc. are improving the outcome of steroid refractory chronic graft-versus-host disease.