A major discovery has been made which explains that changes in genes may cause a significant number of cases of breast cancer.
Experts from the University of Michigan Comprehensive Cancer Centre in the US found that two distinctive genetic rearrangements have been found which could trigger between five and seven per cent of all instances of the disease.
This phenomenon has been witnessed before, and it was linked to blood cancers and rare tumours of soft tissue.
However, it was reported that these changing genes could now also be responsible for some prostate and lung cancer cases.
Published in the online version of Nature Medicine, the researchers looked at the genetic sequencing of 89 breast cancer cell lines and tumours. Recurrent patterns in the MAST kinase and Notch family genes were then found by the experts.
Professor Arul Chinnaiyan explained that the "exciting" thing about this study is that the gene fusions and rearrangements provide targets for new medication and treatments.
"This is a great example of why treating cancer is so challenging. There are so many different ways genes get recombined and so many molecular subtypes, that there's not one solution that will work for all of them," he stated.
"The research provides additional evidence that these types of genetic rearrangements seem to be a significant cause of solid tumours."
Professor Chinnaiyan went on to say that each of the rearrangements were cloned and then introduced to normal breast cell lines, and it was then that the cancer-causing effects appeared.
News of the breakthrough comes after breast cancer screening guidelines in Canada were revised.
The Canadian Task Force on Preventive Health Care told the Canadian Medical Association Journal that an end should be brought to routine mammography screening for those aged between 40 and 49, as the small risk of the disease among that group was outweighed by the chances of over-diagnosis and overtreatment.