Even More Complex

A study published in Nature in April made headlines since its authors concluded that breast cancer's genomic and transcriptomic landscape is so varied that it should really be classified as 10 distinct diseases. A new study published in Nature describes the mutational landscape of breast cancer in great detail, reports the UK Press Association. The researchers described nine new breast cancer oncogenes, bringing the total number of known breast cancer oncogenes to 40, and most of the tumors the team studied had different combinations of driver mutations. Team leader Mike Stratton, of the Wellcome Trust Sanger Institute, tells the Press Association that in 28 samples, there was only one driver mutation, and that the maximum number the team found in an individual case was six. "We found that breast cancer can be caused by more than 70 different combinations of mutations," Stratton adds. "If we consider three breast cancers, each with four driver mutations: they might share none of those driver mutations — so each is a different genetic 'animal'. They are different cancers driven by different genes. We need to classify them as carefully as we can. This study is a step towards that goal."