Assesment of genetic predisposition to breast and ovarian cancer (BRCA1-6 mutations)

Diagnosis of genetic predisposition to breast and ovarian cancerów (BRCA1-6 mutations)

Clinical significance

The mutations are found in every cellór of the body and can be passed from generation to generation inheriting autosomal dominantly. Scientists have identified more than 1,800 mutations in the BRCA1 gene. Many of these mutations are associated with an increased risk of breast and breast cancer in both men and women, as well as in several other typesóof cancer. Not everyone whoóinherits a mutation in the BRCA1 gene will develop cancerór, which is also heavily influenced by other genetic, environmental and lifestyle factors. Most BRCA1 gene mutations lead to a much shorter version of the BRCA1 protein, or prevent any protein from being made from a single copy of the gene, resulting in the introduction of a significant number of errorsóin repairing damaged DNA. As these defects accumulateóy, they can cause cellsóy to grow and divide uncontrollably to form tumors. Many of the same BRCA1 gene mutationsóthat increase the risk of breast cancer also increase the risk of ovarian cancer. Families with these mutations are believed to suffer from a combinationóof hereditary breast and ovarian cancer. Women with BRCA1 gene mutations have a 35 to 60 percent chance of developingóovarian cancer during their lifetime, compared to 1.6 percent in the general population. Sometimes cancers of other organsów (prostate, colon) run in the family. Indications for the study are: - diagnosis of casesów of familial breast cancer (at least 2-3 cases), especially diagnosed before the age of 50;- diagnosis of casesów of ovarian cancer (regardless of age), especially familial cases;- diagnosis of casesów of typical histological forms (medullary cancer), especially without estrogen receptorsós, even with a single incidence in the family;- diagnosis of casesów of atypical forms of breast cancer, especially bilateral, early cancer (before the age of 40.ż.), male breast cancer;- BRCA1 genotyping should be considered before the planned introduction of hormone replacement therapy, especially in young women with diagnosed benign lesions (cysts in the breast or ovaries);- BRCA1 genotyping is indicated between the diagnosis of breast cancer on imaging (confirmed by BAC) and the initiation of anticancer therapy, regardless of pedigree burden;- family studies: detection of BRCA1 gene mutation in a relative with breast or ovarian cancer, indicated testing of all asymptomatic relatives at the latestóź around. 20-30 years of age;