Improving early breast cancer detection: focus on methylation.

The need for additional breast cancer screening tools is indisputably high, as one may conclude from the high rate of interval malignancies in women undergoing regular screening. DNA promoter methylation frequently occurs during breast carcinogenesis and is an early event in this process. Moreover, a field defect for methylation has been described and methylation values can reliably be assessed in limited amounts of DNA. Simultaneous detection of methylation of a panel of genes in breast fluids and/or blood derivatives could be both sufficiently specific and sensitive to be of additive value to current imaging-based screening methods. This review describes the recent developments in methylation detection in breast fluids, serum and plasma that paved the way for large prospective studies. These studies will provide us with the definite answer as to what will be the additive value of defining the methylation status of specific genes to current imaging-based screening methods.