Prognostic Significance of Leukopenia at the Time of Diagnosis in Acute Myeloid Leukemia

We investigated the clinical significance of leukopenia at the time of diagnosis in a cohort of 225 patients with newly diagnosed acute myeloid leukemia (AML) at a single institution. Leukocyte count was treated as a continuous variable and, using a receiver operating characteristic curve (ROC), a cutoff of 3,600/μL had the best sensitivity and specificity for remission (complete remission [CR]), relapse-free survival [RFS], and overall survival [OS]). In a multivariable model, leukopenia at diagnosis had no effects on CR (hazard ratio [HR] = 2.02; confidence interval [CI], 0.9-4.3; P = .07), RFS (HR = 0.93; CI, 0.5-1.5; P = .8), or OS (HR = 1.05; CI, 0.7-1.5; P = .7). No differential expression of cell surface molecules (CD34, c-Kit, CXCR4, PECAM, VLA2, VLA-, VLA4, VLA5, and FLT3) was observed on simultaneously obtained marrow and blood blasts in the high- vs. low-leukocyte groups. We conclude that leukopenia at diagnosis carries no prognostic significance in AML.