title: Absence of terminal deoxynucleotidyl transferase expression identifies a subset of high-risk adult T-lymphoblastic leukemia/lymphoma.
abstract: Terminal deoxynucleotidyl transferase (TdT) can be downregulated in minimal residual disease of T-acute lymphoblastic leukemia/lymphoma (T-ALL/LBL) after chemotherapy. TdT-negative T-ALL/LBL cases are rare and have not been well characterized. We studied the clinicopathologic features of de novo T-ALL/LBL patients treated at our institution during 2003-2011, with an emphasis on immunophenotype and survival of TdT-negative versus TdT-positive cases. Absence of TdT expression was defined as <10% lymphoblasts positive. Seven (12%) TdT-negative cases were identified from a cohort of 59 de novo T-ALL/LBL. The TdT-negative and TdT-positive cases were similar with regard to gender, percentage of patients with a high leukocyte count (>100 × 10(9)/l), central nervous system involvement, and an abnormal karyotype. However, patients with TdT-negative T-ALL/LBL had a significantly higher rate of disease progression and shorter overall survival. Although not statistically significant, TdT-negative T-ALL/LBL cases were associated with an older median age and higher percentage of 'early T precursor' (ETP) immunophenotype than TdT-positive cases. Absence of TdT expression identifies a subset of high-risk T-ALL/LBL that overlaps with, but is not identical to, the ETP leukemia, providing additional prognostic value.
authors.affiliation: Department of Hematopathology, University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhou
authors.forename: Xiangshan
authors.initials: X
authors.lastname: Fan
authors.forename: Mark
authors.initials: M
authors.lastname: Routbort
authors.forename: C
authors.initials: C
authors.lastname: Cameron Yin
authors.forename: Rajesh
authors.initials: R
authors.lastname: Singh
authors.forename: Carlos
authors.initials: C
authors.lastname: Bueso-Ramos
authors.forename: Deborah A
authors.initials: DA
authors.lastname: Thomas
authors.forename: Denái R
authors.initials: DR
authors.lastname: Milton
authors.forename: L Jeffrey
authors.initials: LJ
authors.lastname: Medeiros
authors.forename: Pei
authors.initials: P
authors.lastname: Lin
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D004253:DNA Nucleotidylexotransferase / Q000378:metabolism*; D005260:Female; D006801:Humans; D016130:Immunophenotyping; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D054218:Precursor T-Cell Lymphoblastic Leukemia-Lymphoma / Q000378:metabolism* / Q000473:pathology; D011379:Prognosis; D015996:Survival Rate
chemical_list: D004253:DNA Nucleotidylexotransferase