However , patients with G/C alleles of IL-18 -137 were correlated with a lower clinical stage ( AOR = 0.59 ; 95 % CI = 0.39-0 .89 ; p = 0.01 ) , smaller tumor size ( AOR = 0.56 ; 95 % CI = 0.35-0 .87 ; p = 0.01 ) , and non-lymph node metastasis ( AOR = 0.51 ; 95 % CI = 0.32-0 .80 ; p = 0.003 ) .