While a single-nucleotide polymorphisms study (SNPs) has shown that the GG genotype and G allele of rs28416520 within the PIWIL1 gene promoter CpG 67 region are associated with an increased risk of gastric cancer [31], the impact of SNPs of PIWIL1 gene on EOC risk has not been studied. This evidence concerns the gene PIWIL1 and gastric cancer.