title: The evolution of juvenile myelomonocytic leukemia in a female patient with paternally inherited neurofibromatosis type 1.
abstract: The most common myeloid malignancy seen in children with neurofibromatosis type 1 (NF-1) is juvenile myelomonocytic leukemia (JMML), a myeloproliferative disease. The vast majority of these children have inherited the neurocutaneous disease from an affected mother; boys are more often affected than girls. We present the rare finding of a 7-year-old girl with NF-1 who developed JMML. She inherited her NF-1 from the father. At the time of her initial presentation, clonogenic assays of bone marrow mononuclear cells did not show the spontaneous growth of granulocyte-macrophage colony-forming units or hypersensitivity to granulocyte-macrophage colony-stimulating factor that is characteristic of this disorder. After 1 month, repeat evaluations of the patient's clinical and laboratory test results became fully consistent with those for a diagnosis of JMML. This illustrates the stepwise evolution of this myeloproliferative disorder in NF-1 and the importance of close follow-up and reassessment of these patients. Our case is only the second report of JMML in a girl who inherited NF-1 from her father.
authors.affiliation: Department of Pediatrics, The Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: Elaine W
authors.initials: EW
authors.lastname: Leung
authors.forename: Wilma
authors.initials: W
authors.lastname: Vanek
authors.forename: Mohamed
authors.initials: M
authors.lastname: Abdelhaleem
authors.forename: Melvin H
authors.initials: MH
authors.lastname: Freedman
authors.forename: Yigal
authors.initials: Y
authors.lastname: Dror
mesh_terms: D001853:Bone Marrow / Q000473:pathology*; D002648:Child; D005260:Female; D006801:Humans; D015477:Leukemia, Myelomonocytic, Chronic / Q000150:complications* / Q000175:diagnosis* / Q000473:pathology; D009190:Myelodysplastic Syndromes / Q000150:complications; D009196:Myeloproliferative Disorders / Q000150:complications; D009456:Neurofibromatosis 1 / Q000150:complications* / Q000235:genetics / Q000473:pathology