Complete remission of idiopathic myelofibrosis following donor lymphocyte infusion after failure of allogeneic transplantation: demonstration of a graft-versus-myelofibrosis effect.

A patient with idiopathic myelofibrosis (IM) in the osteosclerotic phase received an allogeneic stem cell transplant. Hemopoietic engraftment was rapid, and full donor chimerism was observed on day +70. However, a few months later, replacement of donor hemopoiesis by the patient's 20q- cell clone was observed, followed by reappearance of the blood IM features, marrow fibrosis and osteosclerosis. At 8 months from transplant donor lymphocytes were infused, which induced chronic GVHD. This resulted in normalization of the blood, with disappearance of the fibrosis and osteosclerosis, effects which persisted 20 months later. This case provides evidence for a graft-versus-disease effect in IM.