CDKN2A and metastatic malignant neoplasm in the lymph nodes: Comparison of methylation profiles of the 12 breast cancer candidate genes in the paired lymph node metastasis to the matched normal tissue showed significantly higher methylation levels for APC, BMP6, BRCA1 and P16 genes (P < 0.05 and P < 0.01, P < 0.0001, P < 0.05; respectively).