Based on the results of univariate logistic regression, the history of estrogen therapy (yes vs. no, OR = 2.712, 95%CI: 1.163–6.325), soybean intake (≥1 vs. <1 time/week, OR = 0.420, 95%CI: 0.233–0.758), and regular sports (≥1 vs. <1 time/week, OR = 0.606, 95%CI: 0.392–0.938) are significantly related with OPRM1 hypermethylation in tumor tissue DNA. This evidence concerns the gene OPRM1 and neoplasm.