Selected aspects of genetic counselling for BRCA1 mutation carriers

Genetic counselling is a process which should explain to the patient all problems caused by development of hereditary disease in the family or risk of such disease [1]. Within counselling the patient should obtain full information about: the disease, its course, possibilities of treatment, genetics, risk of disease for particular family members including planned/unborn children, proceeding (which takes into account actual knowledge, convictions, life priorities) which allow to apply optimal prophylactics, treatment and adaptation to actual life situation [1,2].Dynamic development of molecular genetics made possible the diagnosis of a large number of diseases which hereditary background was until recently unknown. Hereditary neoplasms including breast and ovarian cancers belong to this group of disorders. The oldest report on familial breast cancer was made in about 100 BC in the medical literature of ancient Rome [3]. The first report on familial aggregation of breast cancer in modern times was published in 1866 by Broca, who described 10 cases of breast cancer in four generations of his wife's family [4]. However, only in the middle of the 1990s was it proved at a molecular level that a significant number of breast and ovarian cancers have hereditary monogenic aetiology [5,6] and testing of BRCA1 and BRCA2 mutations became a common diagnostic tool to identify persons with high risk of these cancers. It has been estimated that in BRCA1 or BRCA2 carriers the risk of breast cancer reaches up to 80%, and of ovarian cancer 40% [7]. But, what is more important, early prophylactics allow this risk to be decreased to levels slightly exceeding population risk [8-10]. In Poland, thanks to the detection of founder mutations in the BRCA1 gene [11], which constitute a very high ratio of all detectable BRCA1 and BRCA2 mutations [11-16], as well as setting up a network of hereditary cancer units, diagnosis of persons with high risk of breast/ovarian cancers has become relatively