Study type : Interventional Study design: Diagnostic,Prospective,Non Randomised,Blinded,Efficacy study~Further study details as provided by DBCG ( Danish Breast Cancer Cooperative Group):~Primary outcome measures:~Diagnostic outcome of a yearly screening with MR versus combined mammography and ultrasound of the breast measured by accuracy, sensitivity, specificity, positive and negative predictive values.~Secondary outcome measures:~Comparison of diagnostic outcome of MR versus combined mammography and ultrasound, in women with dense breast tissue compared with women with fatty breast tissue.~Comparison of the cancers found in women with BRCA gene mutations compared with the cancers found in the background population in respect of morphology, size, histological type, axillary lymph node status and grade.~Study start : January 2007. Expected completion 2010.~Women with BRCA gene mutations are more likely than others to develop the disease at a young age when breast density is higher than at older age.The tumours often are more rapidly developing with a short presymptomatic phase. These factors are known to reduce the effectiveness of screening with mammography and mammography seems to have a low sensitivity in women with BRCA gene mutations. Other studies have shown that more than 50% of the cancers appears as interval cancers between two mammography screening examinations and many have positive axillary nodes at the time of diagnosis.~Around 610 women are tested BRCA gene positive in Denmark in year 2006. These women are offered a yearly screening with mammography combined with ultrasound and a clinical examination. The trial will test whether this screening offer should be combined with or replaced by MR mammography.
The purpose of the study is to determine whether MR of the breast is a better screening tool than mammography combined with ultrasound of the breast in women with BRCA1 or BRCA2 gene mutations.