a small trendP = .06
A study observed a small trend for higher levels of serum folate in the group of patients with methylated tumours, compared to those with unmethylated tumours ( P = .06); moreover it was observed a trend for association between serum folate/vitamin B12 levels and gene promoter methylation: higher serum folate/vitamin B12 levels were strongly associated with promoter methylation of P16 and had an association (trend) with promoter methylation of MLH1 and MLH2 genes [ 127 ].