title: Lineage switch at relapse of childhood acute leukemia: a report of four cases.
abstract: Lineage switch in acute leukemia is an uncommon event at relapse, and therefore rarely reported in the literature. Here, we have described the clinical laboratory features of four cases in which the cell lineage switched from acute lymphoblastic leukemia (ALL) to acute myeloid leukemia (AML). One patient was initially diagnosed with B-ALL, switched to T-ALL at the first relapse, and eventually, AML at the second relapse. A lineage switch represented either relapse of the original clone with heterogeneity at the morphologic level or emergence of a new leukemic clone. Further sequential phenotypic and cytogenetic studies may yield valuable insights into the mechanisms of leukemic recurrence, with possible implications for treatment selection.
authors.affiliation: Department of Pediatrics, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Meerim
authors.initials: M
authors.lastname: Park
authors.forename: Kyung Nam
authors.initials: KN
authors.lastname: Koh
authors.forename: Bo Eun
authors.initials: BE
authors.lastname: Kim
authors.forename: Ho Joon
authors.initials: HJ
authors.lastname: Im
authors.forename: Seongsoo
authors.initials: S
authors.lastname: Jang
authors.forename: Chan-Jeoung
authors.initials: CJ
authors.lastname: Park
authors.forename: Hyun-Sook
authors.initials: HS
authors.lastname: Chi
authors.forename: Jong Jin
authors.initials: JJ
authors.lastname: Seo
mesh_terms: D000208:Acute Disease; D001853:Bone Marrow / Q000473:pathology; D019070:Cell Lineage; D002648:Child; D002869:Chromosome Aberrations; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D016130:Immunophenotyping; D007223:Infant; D015470:Leukemia, Myeloid, Acute / Q000175:diagnosis* / Q000188:drug therapy / Q000473:pathology; D008297:Male; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000175:diagnosis* / Q000188:drug therapy / Q000473:pathology; D012008:Recurrence; D016879:Salvage Therapy; D014184:Transplantation, Homologous