Abstract
The differential immunophenotypic characteristics of early T precursor (ETP) acute lymphoblastic leukaemia/lymphoma (ALL) remain incompletely characterized. The study group (n = 142) included 106 (74·7%) men and 36 (25·3%) women with a median age of 34·9 years (range, 2–79) at diagnosis. Patients were subtyped by flow cytometry immunophenotyping as follows: 33 (23·2%) ETP; 32 (22·5%) early non-ETP; 60 (42·2%) thymic; and 17 (12·1%) mature. Excepting definitional markers, there was a significant differential expression of the markers CD2, CD10, CD33 and TdT between ETP-ALL and non-ETP-ALL. Positive CD33 expression (≥20% of leukaemic blasts) was detected in 21/33 (63%) ETP-ALL compared with 17/95 (17·9%) non-ETP-ALL (P < 0·001). Notably, targeted anti-CD33 therapy with IMGN779 resulted in significant growth inhibition and increased apoptosis in ETP-ALL cells in vitro. An 11-marker T-ALL immunophenotype score discriminated reliably between ETP and non-ETP ALL. Longitudinal analysis of ETP-ALL cases in this study demonstrated that the immunophenotype may be occasionally dynamic but is largely stable over the disease course. In summary, identification of ETP-ALL might be enhanced by using an 11-marker T-ALL immunophenotype score. CD33 expression is frequent in ETP-ALL, and in vitro data suggest that exploring anti-CD33 therapy in ETP-ALL is warranted.
Original language | English (US) |
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Pages (from-to) | 538-548 |
Number of pages | 11 |
Journal | British Journal of Haematology |
Volume | 186 |
Issue number | 4 |
DOIs | |
State | Published - 2019 |
Keywords
- CD10
- CD33
- T-cell
- flow cytometry
- immunophenotype
- lymphoblastic leukemia/lymphoma
- targeted therapy
ASJC Scopus subject areas
- Hematology
MD Anderson CCSG core facilities
- Biostatistics Resource Group