Background: T lymphocytes play an important role in the immunosurveillance of patients with hematologic malignancies. No study has so far examined the association between the number of lymphocyte subsets at diagnosis and overall survival (OS). We examined this relationship in adult patients with de novo acute myeloid leukemia (AML).
Methods: A longitudinal prospective study was conducted on 28 AML patients. Peripheral blood (PB) and bone marrow (BM) were obtained before chemotherapy to quantify the number of CD4+ and CD8+ T cells, natural killer (NK), invariant NKT (iNKT), and type-1 and type-2 dendritic cells. The Kaplan-Meier and Cox proportional hazard model were used to determine significant association between the number of each cell subtype and survival.
Results: BM counts of CD4+ lymphocytes >506.11/μL and CD8+ T lymphocytes >556.02/μL and a PB count of iNKT cells <0.2/μL were associated with poor OS by univariate analysis (P = 0.015, P = 0.009, P = 0.033 respectively). Multivariate analysis showed that an iNKT count <0.2 cells/μL is an independent prognostic factor for OS.
Conclusion: An iNKT cell number of <0.2/μL confers a poor prognosis in de novo AML patients.