title: [Relapse of biphenotypic leukemia confirmed by molecular study].
abstract: A 60-year-old woman was admitted to our hospital to receive treatment for relapse of biphenotypic leukemia 4 years after her initial presentation. Bone marrow examination revealed 53.5% lymphoblasts, which were classified as ALL-L2 with a normal karyotype. Lymphoblast surface markers were positive for cells of both B-cell and myeloid lineage. Immunoglobulin heavy chain and T-cell receptor gene rearrangements were investigated with PCR. Clonal rearrangement of TCR delta V delta 2-D delta 3 was detected. The same clonal rearrangement of TCR delta was found using frozen initial leukemic cells. Rather than secondary leukemia, the patient's leukemia was confirmed as relapse of the initial clone. Detection of the clonal rearrangement was also useful as a patient-specific marker for minimal residual disease.
authors.affiliation: Department of Gastroenterology and Hematology, Hokkaido University Graduate School of Medicine.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Onozawa
authors.forename: Satoshi
authors.initials: S
authors.lastname: Hashino
authors.forename: Koh
authors.initials: K
authors.lastname: Izumiyama
authors.forename: Masakatsu
authors.initials: M
authors.lastname: Yonezumi
authors.forename: Kouji
authors.initials: K
authors.lastname: Chiba
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kondo
authors.forename: Junji
authors.initials: J
authors.lastname: Tanaka
authors.forename: Masahiro
authors.initials: M
authors.lastname: Imamura
authors.forename: Masahiro
authors.initials: M
authors.lastname: Asaka
mesh_terms: D005260:Female; D015329:Gene Rearrangement, T-Lymphocyte / Q000235:genetics; D006801:Humans; D008875:Middle Aged; D018365:Neoplasm, Residual; D010641:Phenotype; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics*; D012008:Recurrence