CD4 Lymphopenia As a Risk Factor for Febrile Neutropenia and Early Death After Cytotoxic Chemotherapy in Adult Patients with Cancer

Background: Lymphopenia is frequently observed in patients with cancer and correlates with the risk of febrile neutropenia and early death after chemotherapy. The phenotype of the depleted lymphocyte populations was investigated in the current study.

Methods: Peripheral blood lymphocyte subsets (CD3, CD4, CD8, CD19, CD56) were quantified on Day 1 using fluorescence-activated cell sorting in a prospective study of 213 patients with cancer treated with chemotherapy in a single oncology ward during 12 months. Correlations between lymphocyte phenotype, clinical characteristics, and the risk of febrile neutropenia and early death within 31 days after chemotherapy were investigated in univariate and multivariate analyses.

Results: Total lymphocyte count and CD3, CD4, and CD8 lymphocyte subsets were significantly lower in patients who experienced febrile neutropenia. Total lymphocyte count and CD3, CD4, CD8, CD19, and CD56 lymphocyte subsets were significantly lower in patients who died within 31 days after chemotherapy. Using logistic regression, CD4 lymphopenia (< 450/muL; odds ratio [OR] = 2.9, 95% confidence interval [CI] = 1.5-5.9) and the dose of chemotherapy (OR = 3,9, 95% CI = 2.0-7.8) were both identified as independent risk factors for febrile neutropenia. Fifty-four percent of patients with both risk factors experienced febrile neutropenia. CD4 lymphocyte count < 450/muL was also an independent risk factor for early death (OR = 7.7, 95% CI = 1.7-35). Thirteen percent of patients with a CD4 lymphocyte count </= 450/muL died within 31 days after chemotherapy. Eighty-seven percent (14 of 16) of patients who died before Day 31 had a CD4 lymphocyte count < 450/muL.

Conclusions: A low CD4 count was an independent risk factor for febrile neutropenia and early death in patients receiving cytotoxic chemotherapy.