title: Cytogenetic findings and clinical features in acute leukemia and transient myeloproliferative disorder in Down's syndrome.
abstract: Cytogenetic, immunologic, and electron microscopic studies were performed on the blast cells of 28 pediatric patients with Down's syndrome, 13 with acute leukemia (DS-AL) and 15 with transient myeloproliferative disorders (DS-TMD). Clonal chromosome abnormalities were found in the cells of all patients with DS-AL but not those with DS-TMD. The younger ages and higher hemoglobin concentrations, platelet counts, and WBC counts of DS-TMD patients provided a clinical contrast with the frankly leukemic cases. Myelodysplastic syndrome, characterized by a small percentage of leukemic blast cells, was observed in 11 of the 13 patients with DS-AL compared with none in the DS-TMD group. Electron microscopy disclosed a positive platelet peroxidase reaction in each of the 11 DS-TMD patients and in nine of the 13 DS-AL patients. Immunologic studies revealed antiplatelet-megakaryocyte antigens on the blast cells of the majority of patients in both study groups. Our findings suggest that the blast cells in cases of DS-AL and DS-TMD arise from cells of the megakaryocytic lineage or from a myeloid progenitor with the capacity for megakaryocytic differentiation. The high risk of the development of AL in patients with DS who are less than 3 years old may be related to increased megakaryocyte proliferation in this age group.
authors.affiliation: Division of Hematology/Oncology, Saitama Children's Medical Center, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Hayashi
authors.forename: M
authors.initials: M
authors.lastname: Eguchi
authors.forename: K
authors.initials: K
authors.lastname: Sugita
authors.forename: S
authors.initials: S
authors.lastname: Nakazawa
authors.forename: T
authors.initials: T
authors.lastname: Sato
authors.forename: S
authors.initials: S
authors.lastname: Kojima
authors.forename: F
authors.initials: F
authors.lastname: Bessho
authors.forename: S
authors.initials: S
authors.lastname: Konishi
authors.forename: T
authors.initials: T
authors.lastname: Inaba
authors.forename: R
authors.initials: R
authors.lastname: Hanada
mesh_terms: D000208:Acute Disease; D000911:Antibodies, Monoclonal; D001773:Blood Cells / Q000648:ultrastructure; D001853:Bone Marrow / Q000648:ultrastructure; D002675:Child, Preschool; D003582:Cytogenetics; D004314:Down Syndrome / Q000097:blood / Q000235:genetics* / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D007231:Infant, Newborn; D007938:Leukemia / Q000097:blood / Q000235:genetics* / Q000473:pathology; D008297:Male; D008854:Microscopy, Electron; D009196:Myeloproliferative Disorders / Q000097:blood / Q000235:genetics* / Q000473:pathology
chemical_list: D000911:Antibodies, Monoclonal