Prognostic significance of leukopenia during the induction phase in adult B cell acute lymphoblastic leukemia

The association between chemotherapy-induced leukopenia and clinical outcome has been reported for several types of cancer. The objective of the current study was to evaluate the association of chemotherapy-induced leukopenia during the induction phase with the clinical outcome of adult B cell acute lymphoblastic leukemia (B-ALL). Fifty-one cases of B-ALL, age ≥14 years, were reviewed. The variables under consideration included age, sex, the initial white blood cell (WBC) count (WBC-0), as well as the WBC counts on days 8 (WBC-8), 15 (WBC-15), and 22 (WBC-22) during induction therapy, early bone marrow responses on day 15 during induction therapy, immunophenotype, and cytogenetics. Univariate analysis revealed that WBC-15 ≥0.40×109/L was significantly associated with inferior event-free survival (EFS) (hazard ratio [HR]=2.95, P=0.004) and overall survival (OS) (HR=2.92, P=0.015). On multivariate analysis, high WBC-15 (≥0.40×109/L) remained an independent prognostic factor for EFS (HR=3.29, P=0.014) and OS (HR=3.29, P=0.038). Our results suggested that WBC-15 may contribute to refinements in the current risk stratification algorithms for adult B-ALL.