title: Development of T-cell acute lymphoblastic leukemia in a patient in very long lasting complete remission of juvenile myelomonocytic leukemia.
abstract: Juvenile myelomonocytic leukemia (JMML) occurs with an incidence of 1.2 per million children a year, and represents 18% to 30% of all myelodysplastic (MDS) and myeloproliferative (MPS) disorders in the age group below 15, being by far the most common MDS/MPS in children younger than 4 years. The only therapeutic approach which results in a definitive cure of patients with JMML is myeloablative chemo-therapy/radio-therapy, followed by allogeneic hematopoietic cell transplantation. Few cases of transformation of JMML in acute lymphoblastic leukemia have been reported. We describe a child with JMML diagnosed at the age of 4 months in whom complete remission was achieved with 13-cis retinoic acid and cytosine-arabinoside and was sustained for 7 years with no maintenance therapy. Ninety-eight months after the diagnosis of JMML was established, overt T-cell leukemia developed. Treatment with acute lymphoblastic leukemia (ALL)-directed chemotherapy induced complete restoration of normal hemopoiesis, but testicular involvement persisted. The patient died after transplantation with unrelated cord blood. This case suggests that JMML is a true stem cell disorder and that stem cell transplantation should be considered, even in patients with a very favorable clinical course.
authors.affiliation: Federal Research Center for Pediatric Hematology, Oncology, and Immunology, Moscow, Russian Federation. amaschan@mail.ru
authors.forename: Alexei A
authors.initials: AA
authors.lastname: Maschan
authors.forename: Lili A
authors.initials: LA
authors.lastname: Khachatrian
authors.forename: Galina G
authors.initials: GG
authors.lastname: Solopova
authors.forename: Elena Yu
authors.initials: EY
authors.lastname: Ossipova
authors.forename: Luidmila V
authors.initials: LV
authors.lastname: Baidun
authors.forename: Svetlana V
authors.initials: SV
authors.lastname: Dmitrieva
authors.forename: Mikhail A
authors.initials: MA
authors.lastname: Maschan
authors.forename: Igor B
authors.initials: IB
authors.lastname: Resnik
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D017809:Fatal Outcome; D006801:Humans; D007223:Infant; D054429:Leukemia, Myelomonocytic, Juvenile / Q000150:complications / Q000175:diagnosis / Q000628:therapy; D008297:Male; D054218:Precursor T-Cell Lymphoblastic Leukemia-Lymphoma / Q000150:complications* / Q000175:diagnosis / Q000628:therapy; D012074:Remission Induction; D013997:Time Factors