Lymphocyte subsets in pediatric acute lymphoblastic leukemia and their prognostic value.

To study the changes of lymphocyte subsets in children with acute lymphoblastic leukemia (ALL) at initial diagnosis and compare them with those of healthy children and patients who have achieved complete remission (CR). Furthermore, we aim to analyze the prognostic significance of lymphocyte subsets in these patients. From May 2011 to December 2015, 405 children with ALL were enrolled in this study. Peripheral blood was collected at the time of diagnosis, and lymphocyte subsets were detected by flow cytometry. Then, the percentages of lymphocyte subsets in each group were compared. In addition, survival and prognostic factor analyses were performed to determine the prognostic value of lymphocyte subsets. Lymphocyte subsets in children with ALL were dramatically different from those in healthy children and patients achieving CR. Additionally, lymphocyte subsets were correlated with different minimal residual disease and risk parameters. Furthermore, percentages of CD3+ T cells and CD4+ T cells and the ratio of CD4/CD8 were associated with different clinical outcomes. Multivariate analysis demonstrated the percentage of CD4+ T cell as an independent predictor for clinical prognosis. Lymphocyte subsets in pediatric ALL undergo dramatic changes and were related to prognosis, especially CD4+ T cells.