Low absolute NK cell counts in peripheral blood are associated with inferior survival in patients with mantle cell lymphoma.

Abstract

Background: Although risk stratification of mantle cell lymphoma (MCL) is most frequently performed using the simplified MCL International Prognostic Index (sMIPI), the identification of host-related factors and tumor microenvironment, including absolute monocyte counts (AMC) and peripheral blood T lymphocyte subsets, especially absolute natural killer cell counts (ANKC) has been suggested to be critical in the prediction of prognosis and the guidance of treatment.

Objective: This study was aimed at investigating whether peripheral blood ANKC and AMC at diagnosis had an impact on MCL prognosis.

Methods: A total of 92 newly diagnosed MCL patients was enrolled in this retrospective study. Flow cytometric analysis was conducted on fresh peripheral blood samples with a FACSCalibur flow cytometer (BD Biosciences, San Jose, CA, USA).

Results: The median follow-up was 42 months (range, 2-144 months) and the median overall survival (OS) of all cases was 45 months. High AMC (> 0.6 × 109/L) was the parameter associated with inferior progression free survival (PFS) (P= 0.044) and poor OS (P= 0.028) while low ANKC (⩽ 0.1 × 109/L) was associated with unfavorable OS (P= 0.023) by univariable analysis. Multivariable analysis revealed that only low ANKC (⩽ 0.1 × 109/L) was statistically significant in worse OS (P= 0.009) independent of sMIPI.

Conclusions: Low ANKC (⩽ 0.1 × 109/L) proved to be a significant predictor of inferior OS in patients with MCL.