Low absolute CD4⁺ T cell counts in peripheral blood are associated with inferior survival in follicular lymphoma

Host immunity and tumor microenvironment significantly influence follicular lymphoma (FL) outcomes. Lymphopenia has been identified as a negative prognostic factor for FL. However, there is limited data regarding prognostic value of peripheral blood T lymphocyte subsets, especially absolute CD4⁺ T cell counts (ACD4C) in FL. We studied 127 consecutive FL patients to investigate whether peripheral blood ACD4C or absolute monocytes (AMC) at diagnosis had an impact on FL prognosis. In our cohort, both low ACD4C and high AMC were the parameters associated with inferior progression-free survival (PFS) (P = 0.021 and P = 0.013, respectively) and inferior overall survival (OS) (P = 0.020 and P = 0.005, respectively) by univariate analysis. Multivariate analysis revealed that only low ACD4C was statistically significant in worse PFS (hazard ratio, 2.811; 95 % confidence interval, 1.137−6.950; P = 0.025) and shorter OS (hazard ratio, 3.393; 95 % confidence interval, 1.037−11.105; P = 0.043) independent of FLIPI-2. Evaluation of blood ACD4C could be a useful indicator of outcome in previously untreated FL patients.