Low NK cell counts in peripheral blood are associated with inferior overall survival in patients with follicular lymphoma.

Host immune responses influence follicular lymphoma (FL) outcomes. To test our hypothesis that immune cells in blood reflect that response, we assessed by peripheral blood flow cytometry in 75 untreated FL patients the absolute counts of: lymphocytes (ALC), CD4(+)T (ACD4C), CD8(+)T (ACD8C) and natural killer (ANKC) cells. Low ANKC was the only parameter associated with inferior overall survival by univariate analysis (p=0.02), and trended to significance in multivariable analysis with ACD4C (p=0.08). Five (24%) patients with low initial ANKC died, while one (2%) with normal/high ANKC has died. In conclusion, evaluation of blood ANKC may be a useful indicator of outcome in previously untreated FL patients.