An unusual long-term outcome of a child with primary myelofibrosis harboring a JAK2 mutation.

We report an extremely rare case of a female child who presented the onset of primary myelofibrosis (PMF) harboring JAK2 (Janus Kinase 2 gene) mutation (JAK2V617F) when she was 15 months old. She was monitored over 25 years, a period in which she was treated with spleen radiotherapy and recombinant interferon α. She also underwent splenectomy when she was 13 years old, due to massive splenomegaly, anemia and various infection disease episodes. The longstanding evolution of the patient enabled us to verify that there were no complications related to post-splenectomy events and/or blast transformation. To the best of our knowledge, this is the first reported case of severe PMF with JAK2 mutation in a child. We provide evidence that a better quality of life and long survival in pediatric PMF may be provided by splenectomy.