Cancer as a legacy

Breast cancer in men is rare

Very rarely, breast cancer can also occur in men – there are 50 cases per year in Switzerland. If a man develops breast cancer, this always results in a genetic test. This is because men can also pass on the defective gene to their children. The BRCA2 gene is particularly frequently affected. However, the recommendations for prevention are “less clear” than for women, as the gene occurs much less frequently in men, says Esther Birindelli. It is recommended to go for prostate screening at the age of 40 instead of 50, because prostate cancer is more common in men with this risk gene.

Many of Esther Birindelli’s consultations are not with cancer patients, but with people seeking advice who want to know whether they carry cancer genes because cancer runs in their family. In such cases, it draws up a risk profile that includes information on lifestyle as well as the family tree. If there is an increased risk, the specialist applies to the health insurance company for a cost approval for a genetic test from the blood. This costs around 4,000 francs.

Genetic analysis for diagnosis and therapy

If a mutation is found in a tumor, a blood test can be used to determine whether it is hereditary. Other tests of tumor genes influence treatment: such tests are now available for more than 400 disease-causing genes. “It is rather rare for us to examine tumor tissue or cells for all known changes,” says Achim Weber, Deputy Director of the Institute of Pathology and Molecular Pathology. As a rule, the aim is to find the right therapy with a genetic test. “For many types of cancer, we know exactly which genes we need to look at,” explains Achim Weber. In most cases, the changes in the genetic material are random, which occurs more frequently with increasing age. The defective genes are then found in the tumor cells. Rather rarely, the mutations affect egg and sperm cells (germ cells) and can then be passed on to the next generation.

Several types of cancer are known to have a hereditary cause, including certain forms of stomach, bowel, prostate and pancreatic cancer as well as malignant melanoma. But it is often complex. In addition to BRCA1 and BRCA2, other genes are known to increase the risk of breast cancer. “You have to think carefully beforehand about what you want to test and what the consequences are,” emphasizes specialist Esther Birindelli. She would therefore like to know during the human genetics consultation: What can reassure the person being tested? Is a negative result for the two most important genes enough for her, or does she want to have all of them tested? What would be the consequences of a positive result? Would the person concerned take preventive measures? Who in the family do you inform and who not?

Who do you want to inform?

A test for a hereditary predisposition to cancer is always a family matter. Breast cancer, for example, can be passed on to offspring with a 50 percent risk. Second-degree relatives such as aunts or uncles are therefore also affected – depending on from whom the defective gene was transmitted. Esther Birindelli recommends that people who are willing to test should talk to their family in advance. If someone does not want to know the result, she advises them not to bring up the subject of the test in future. In the other case, she recommends passing on the detailed report at the end: “Then the person – or the doctor treating them – knows straight away which gene they need to look for.” And even if a further search is unnecessary.