Therapy by omission: observation as a strategy in JMML

In this issue of Blood, Neven et al 1 challenge the longstanding dogma that nearly all patients with juvenile myelomonocytic leukemia (JMML) should proceed to hematopoietic stem cell transplantation (HSCT) shortly after diagnosis.The authors analyzed a cohort of 161 patients diagnosed with JMML in France over a 20-year period starting in 2001.Their data suggest that nearly one-third of patients with newly diagnosed JMML can safely avoid HSCT with little to no therapy at all.These observations will lead to pediatric oncologists rethinking their approach to treatment for patients with JMML.