The quantitative methylation analysis of the 12 studied genes in the present cohort showed higher methylation proportion for the primary tumor tissue versus matched normal tissue and the differences were significant for APC, BIN1, BMP6, BRCA1, CST6, ESR-b, P16, PTEN and TIMP3 promoter regions (P < 0.05, P < 0.05, P < 0.01, P < 0.0001, P < 0.01, P < 0.01, P < 0.05, P < 0.05, P < 0.01; respectively). The gene discussed is PTEN; the disease is neoplasm.