Genetic Counseling

Breast cancer is the most common cancer in women. In Switzerland, more than 6000 women are diagnosed with breast cancer, every year. An accumulation of breast cancer cases in the family, an age of onset below 45 years or the lack of hormone and antibody receptors on the tumor (so-called triple negative breast carcinoma) can indicate the presence of a hereditary breast and ovarian cancer syndrome (BRCA mutation). The ovarian cancer occurs less frequently. However, women with ovarian cancer are more likely to be carriers of a BRCA mutation.

Sections of DNA that are responsible for the production of proteins, are called genes. Humans have at least 20,000 genes distributed on our chromosomes. Chromosomes consist of kilometers of coiled strands of DNA. Each nucleus in our body contains a complete set of chromosomes. This consists of 46 chromosomes, or 23 pairs respectively. One pair forms the sex chromosomes, the gonosomes (XX in females, XY in males). The other 22 pairs are called body chromosomes or autosomes. When a child is conceived, half of the set (23 chromosomes) is passed from the mother and the other half is passed from the father. Thus, after fertilization, 46 chromosomes are again contained in one cell.

Genetic changes such as the BRCA mutation lead to a significantly higher risk of developing breast or ovarian cancer in the affected.If the genetic code of a cell changes, a tumor cell can develop from a normal cell. There are genes that suppress this tumor development: the so-called tumor suppressor genes. If these genes are altered, i.e. mutated, they can no longer perform their task properly and there is an increased susceptibility to tumor diseases. In most tumor diseases, a gene mutation occurs sporadically. This means that there is no familial accumulation. If a hereditary tumor disease is present, a gene mutation is detectable in all body cells. Mutations may be new, or have been inherited from one of the parents.

BRCA mutations are inherited autosomal dominant.An autosomal inheritance means, that the inheritance ist independent of gender, i.e. it occurs equally in males and females. Dominant means that one single altered gene is sufficient for the disease to be expressed. The risk of inheriting a BRCA mutation to offspring is 50%.

Affected individuals or their relatives can perform a genetic testing. Genetic changes in the nuclei of blood cells can be detected via a blood analysis. Prior to testing comprehensive genetic counseling should be provided to prepare the tested person for the consequences of a possible mutation detection. Knowledge of the presence of a mutation enables measures to be taken to detect cancer at an early stage or prevent it. Certain criteria must be met for the costs of the blood-analysis to be covered by health insurance. Prior to the test, the genetic counselour should obtain a cost approval from the health insurance company.

We will be happy to advise you individually and evaluate your cancer risk for breast and/or ovarian cancer together with you. If the criteria for genetic testing are met, or if you wish, we will carry out the testing. The consultation and testing is carried out in cooperation with the Department of Medical Genetics of the Kantonsspital Aarau, with which we have been working closely for many years.