Clinical Presentation and Survival Outcomes of B-cell versus T-cell Acute Lymphoblastic Leukemia

Background: Acute lymphoblastic leukemia (ALL) is associated with poor outcomes in adults, but limited data exist regarding the comparative impact of B-cell versus T-cell immunophenotype in the modern treatment era. Methods: We conducted a retrospective study to adult ALL patients treated at our institution between January 2017 and August 2023. Baseline characteristics, mutational profiles, treatment responses, and survival outcomes were compared across B-cell versus T-cell immunophenotype ALL. Results: A total of 160 patients were diagnosed with ALL and treated at our institution between 01/2017 and 08/2023. Among them, 124 were B-cell (77%), and 36 were T-cell ALL (23%). Among the cohort, B-cell ALL was associated with older age at diagnosis (median 61 vs. 38 years), higher prevalence of high-risk cytogenetics (35% vs. 0%), and more frequent TP53 mutations (20% vs. 0%) ( P = 0.06). In addition, initial disease burden was higher in B-cell patients, including greater bone marrow blast percentage, lower hemoglobin, and lower platelet count (all P < 0.01). Despite these adverse features, there were no statistically significant differences in composite complete response (CCR) rates (72% vs. 84%, P = 0.2), minimal residual disease (MRD) negativity, or cytogenetic response between B-cell and T-cell ALL. Conclusion: Our findings suggest that incorporating MRD assessment and targeted therapies in the contemporary treatment era leads to more comparable outcomes in adult B-cell and T-cell ALL than what was historically reported. These results support the need for further immunophenotype-specific risk stratification in future studies.