curing a child of JMML. With HSCT, recent research studies have found the survival rate to be approximately 50%. Relapse is a significant risk after HSCT for children with JMML. It is the greatest cause of death in JMML children who have had stem cell transplants. Relapse rate has been recorded as high as 50%. Many children have been brought into remission after a second stem cell transplant. After bone marrow transplant, the relapse rate for children with JMML may be as high as 50%. Relapse often occurs within a few months after transplant and the risk of relapse drops considerably at the one-year point after transplant. A significant number of JMML patients do achieve complete remission and long-term cure after a second bone marrow transplant, so this additional therapy should always be considered for children who relapse. Frequency JMML accounts for 1–2% of childhood leukemias each year; in the United States, an estimated 25-50 new cases are diagnosed each year, which also equates to about 3 cases per million children. There is no known environmental cause for JMML. Since about 10% of patients are diagnosed before 3 months of age, it is thought that JMML is a congenital condition in these infants History Juvenile myelomonocytic leukemia (JMML) is a myelodysplastic and myeloproliferative disorder. The diagnostic criteria were originally laid down by Neimeyer et al. in 1997 and 1998 and were incorporated in the WHO classification in 2008. See also List of cutaneous conditions Hematologic disease List of cancer types References External links Chronic myeloid leukemia Epidermal nevi, neoplasms, and cysts Pediatric cancers Rare cancers