[Diagnostic molecular biology in breast cancer].

Studies of molecular genetic changes in breast carcinoma are slowly improving our understanding of the biological process which leads to a normal breast epithelial cell becoming a carcinoma cell with invasive and metastatic properties. Carriers of germ-line mutations in the breast cancer susceptibility genes BRCA1 and BRCA2 are particularly prone to develop breast cancer. Genetic screening and counselling programs have been established to identify individuals at high risk and provide intervention to reduce the suffering and mortality associated with breast cancer. In the future, the identification of specific molecular genetic changes in tumours may be applied as diagnostic and prognostic tools. An improved understanding of the molecular genetic mechanisms underlying the development of breast cancer may eventually yield novel therapeutic strategies, attacking specific genetic changes in the tumour.