The Symptomatic Nature of Chronic Graft-Versus-Host Disease

Hi, my name is Dr Yi-Bin Chen. I direct the transplant and cell therapy program at Massachusetts General Hospital. So, let's talk a little bit about chronic graft versus host disease. When we transplant patients, graft-versus-host disease is a big complication, a major complication, that we discuss with patients. Quite simply, we do a transplant to have the donor hematopoietic system replace the recipient system, and in doing so, the donor's immune system reconstitutes in the recipient. We hope that new immune system does protect the recipient from infection, but also if there's any residual malignancy left, either then or in the future, that the donor's immune system can attack the residual malignancy, this graft versus malignancy effect. The main toxicity of that effect has always been graft-versus-host disease. So, that's where donor cells recognize the recipient's normal body is foreign. There are two flavors of graft versus host disease, acute and chronic.  

Acute is generally early and characterized by a skin rash, diarrhea, or liver test abnormalities. Chronic graft-versus-host disease mostly takes place after three to six months. The name chronic also means it's a bit more indolent, lasts a longer time. And if you look at all the series, when we start to treat chronic graft-versus-host disease, we generally don't expect a complete resolution or a complete response. And so, patients do deal with the burden of chronic graft-versus-host disease. If you look at large studies of transplant patients, it's the single most important factor that determines long-term quality of life. So we have a vested interest in trying to prevent it and treat it better. It is acknowledged over the last decade that we've made big leaps in the progress of the prevention of both acute and chronic graft-versus-host disease. So, I think all of us are grateful for that progress as we see improving outcomes for our patients and maybe a decreasing average burden of chronic graft-versus-host disease. But the truth is, we're transplanting more patients. We're transplanting older patients. There's an increasing number of survivors as therapy for malignancy improves. And so, the overall burden of chronic graft-versus-host disease going forward is not decreasing drastically, and we are treating many patients with this complication.