KLRD1 and central nervous system cancer: Patients with grade 3 glioma exhibiting a frequency of CD56+/CD94+ NK cells below a cut-off value of 7.2% were considered as the low CD56+/CD94+ NK cell group (n = 14; 7 oligodendroglioma, 7 astrocytoma), whereas patients with a frequency of CD56+/CD94+ NK cells above 7.2% were considered as the high CD56+/CD94+ NK cell group (n = 14; 6 oligodendroglioma, 8 astrocytoma).