Complex Karyotype with >= 3 Cytogenetic Alterations is a New Marker of Worse Prognosis in Adult T-Cell Acute Lymphoblastic Leukemia (T-ALL)

Background No standardized and widely accepted cytogenetic classification with prognostic impact for adult T-ALL has been proposed to date. Methods Patients with abnormal karyotypes (65/139, 47%) were classified according to the number of chromosomal alterations (Chun K. et al., 2009). Cohort 216 adults T-ALL patients/NCT00853008-NCT01540812/PETHEMA cooperative group. Prognostic impact of karyotype on event-free survival (EFS), overall survival (OS), and cumulative incidence of relapse (CIR) were assessed. Additionally, next-generation sequencing (NGS) experiments were done. Results Greater than three cytogenetic abnormalities were associated with lower rates of both complete remission (CR, 77% vs. 94%; p=0.032) and minimal residual disease (MRD) level Conclusions Compared to BCP-ALL, a lower cut-off to define complex karyotypes based on the presence of ≥3 cytogenetic alterations allows the identification of T-ALL patients with poor prognosis. Interestingly, molecular analyses of patients carrying ≥3 cytogenetic alterations revealed a unique molecular profile that could contribute to understanding the underlying molecular mechanisms of resistance and to evaluate novel targeted therapies (e.g. IL7R-directed) that might improve the response to treatment and outcome of adult T-ALL patients. Funding ISCIII (PI19/01828), co-funded by ERDF/ESF, \"A way to make Europe\"/\"Investing in your future\".