Lineage switch with t(6;11)(q27;q23) from T-cell lymphoblastic lymphoma to acute monoblastic leukemia at relapse.
We present a patient with T-cell lymphoblastic lymphoma (T-LBL) harboring t(6;11)(q27;q23) that converted to acute monoblastic leukemia at relapse. A 27-year-old man developed T-LBL with a mediastinal mass. He exhibited several recurrences in the central nervous system and marrow. A fifth relapse occurred in the marrow, with 42.8% blasts with CD4, CD5, CD7, CD10, CD33, CD34, HLA-DR and cytoplasmic (cy) CD3. While achieving complete remission with nelarabine, sixth relapse occurred in the marrow with 6.8% blasts, which had characteristics of monoblastic features, 2 months later. Marrow blasts were positive for myeloperoxidase, CD4, CD33, CD56, CD64, and HLA-DR, but were negative for cyCD3, CD5, CD7, CD10, and CD34. Marrow cells at both the 5th lymphoid and 6th myeloid relapses had t(6;11)(q27;q23) and the same MLL-MLLT4 fusion transcript. In addition, the MLL-MLLT4 fusion sequences documented in the initial mediastinal cells were the same as seen in peripheral blood cells at the 6th relapse. The patient continues 7th remission after one course of gemtuzumab ozogamicin therapy followed by cord blood transplantation for more than 3 years. Sequential phenotypic and cytogenetic studies may yield valuable insights into the mechanism of leukemic recurrence and possible implications for treatment selection.
Department of Hematology, Kumamoto University School of Medicine, Kumamoto.
Yusuke
Y
Higuchi
Department of Hematology, Kumamoto University School of Medicine, Kumamoto.
Kenji
K
Tokunaga
Department of Hematology, Kumamoto University School of Medicine, Kumamoto.
Yuko
Y
Watanabe
Department of Hematology, National Institute of Kumamoto Medical Center, Kumamoto.
Toshiro
T
Kawakita
Department of Hematology, National Institute of Kumamoto Medical Center, Kumamoto.
Naoko
N
Harada
Department of Hematology, Kumamoto University School of Medicine, Kumamoto.
Shunichiro
S
Yamaguchi
Cancer Center, Kumamoto University Hospital, Kumamoto.
Kisato
K
Nosaka
Department of Hematology, Kumamoto University School of Medicine, Kumamoto.
Hiroaki
H
Mitsuya
Department of Hematology, Kumamoto University School of Medicine, Kumamoto; Department of Hematology, International Medical Center, Saitama Medical University, Saitama, Japan. Electronic address: ktcnasou@saitama-med.ac.jp.
Norio
N
Asou
D000328:Adult; D002880:Chromosomes, Human, Pair 11; D002896:Chromosomes, Human, Pair 6; D006801:Humans; D059785:Karyotype; D007948:Leukemia, Monocytic, Acute / Q000235:genetics* / Q000473:pathology; D015458:Leukemia, T-Cell / Q000235:genetics* / Q000473:pathology; D008297:Male; D012008:Recurrence; D014178:Translocation, Genetic
Lineage switch; MLL-MLLT4 (AF6); T-cell lymphoblastic lymphoma; acute monoblastic leukemia; t(6;11)(q27;q23)