title: Juvenile myelomonocytic leukemia characterized by cutaneous lesion containing Langerhans cell histiocytosis-like cells.
abstract: We present a 1-year-old boy who developed a cutaneous lesion on the trunk and hepatosplenomegaly. Laboratory examination showed leukocytosis with peripheral blasts, atypical monocytosis, anemia, hyper IgG, and a mild elevation of C-reactive protein. Clinical features and skin biopsy findings matched the diagnostic criteria of both juvenile myelomonocytic leukemia (JMML) and Langerhans cell histiocytosis (LCH). Histopathology revealed atypical mononuclear cells that had infiltrated around vessels throughout the dermis in a skin biopsy specimen. These cells were CD1a (+), S-100 (+), CD68 (+), CD207 (-), lysozyme (+), and myeloperoxidase (-). The diagnosis of JMML was confirmed by detection of spontaneous colony formation and granulocyte-macrophage colony-stimulating factor hypersensitivity in vitro, and a somatic NRAS point mutation. Transplantation of bone marrow from an HLA-matched unrelated donor was performed, and the marrow was successfully engrafted. The cutaneous lesion and hepatosplenomegaly were improved at the time of discharge. It is often difficult to distinguish between JMML and LCH-like infiltrates by assessing clinical and light microscopic features of various cutaneous lesions. In the current case, molecular biological analysis enabled us to develop a precise diagnosis.
authors.affiliation: Department of Pediatrics and Child Health, Kurume University School of Medicine, 67 Asahi-machi, Kurume, Fukuoka, 830-0011, Japan. ohzono_shyuuichi@kurume-u.ac.jp.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Ozono
authors.affiliation: Department of Pediatrics and Child Health, Kurume University School of Medicine, 67 Asahi-machi, Kurume, Fukuoka, 830-0011, Japan.
authors.forename: Hiroko
authors.initials: H
authors.lastname: Inada
authors.affiliation: Department of Pediatrics and Child Health, Kurume University School of Medicine, 67 Asahi-machi, Kurume, Fukuoka, 830-0011, Japan.
authors.forename: Shin-Ichiro
authors.initials: SI
authors.lastname: Nakagawa
authors.affiliation: Department of Pediatrics and Child Health, Kurume University School of Medicine, 67 Asahi-machi, Kurume, Fukuoka, 830-0011, Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Ueda
authors.affiliation: Department of Pediatrics, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Matsumura
authors.affiliation: Department of Pediatrics, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors.forename: Seiji
authors.initials: S
authors.lastname: Kojima
authors.affiliation: Department of Dermatology, Kurume University School of Medicine, Kurume, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Koga
authors.affiliation: Department of Dermatology, Kurume University School of Medicine, Kurume, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Hashimoto
authors.affiliation: Department of Pathology, Kurume University School of Medicine, Kurume, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Oshima
authors.affiliation: Department of Pediatrics and Child Health, Kurume University School of Medicine, 67 Asahi-machi, Kurume, Fukuoka, 830-0011, Japan.
authors.forename: Toyojiro
authors.initials: T
authors.lastname: Matsuishi
mesh_terms: D044466:Asian People; D016026:Bone Marrow Transplantation; D002675:Child, Preschool; D020405:Dermis / Q000473:pathology; D006085:Graft Survival; D006646:Histiocytosis, Langerhans-Cell / Q000175:diagnosis / Q000473:pathology / Q000628:therapy; D006801:Humans; D007564:Japan; D054429:Leukemia, Myelomonocytic, Juvenile / Q000175:diagnosis / Q000473:pathology / Q000628:therapy; D008297:Male; D012878:Skin Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000628:therapy; D014184:Transplantation, Homologous