Familial tumor risk syndromes

In 2022 about 2,7 million people in Europe developed cancer (source ECIS - European Cancer Information System). Cancer is caused by changes in the genetic material of individual cells, which allow cells to grow uncontrollably and spread to other parts of the body. These changes usually occur in the course of life due to errors in cell division or external influences (radioactive and UV radiation, alcohol, cigarette smoke, chemicals, certain infections). The likelihood of their occurrence increases with age, so tumor diseases usually occur sporadically and at an older age.

At least 5-10% of all tumors are hereditary. Hereditary tumor risk syndromes are caused by disease-causing variants in genes that play a role in the processes of tumor development. If such a pathogenic variant is present, the probability of developing certain tumor entities increases significantly compared to the general population. Hereditary tumor risk syndromes include e.g. familial breast and ovarian cancer, familial colorectal cancer, Li-Fraumeni syndrome and multiple endocrine neoplasia.

Indicators of a hereditary tumor risk syndrome

Depending on the underlying genetic alteration, certain constellations of tumors and associated physical abnormalities may occur in affected individuals and families. Essential general characteristics of a tumor risk syndrome are

- Occurrence of cancer at a young age (before the age of 51)

- Several different tumors in one individual

- Accumulation of tumors in the family (especially at a younger age)

- Occurrence of rare tumors

- Conspicuous fine tissue/molecular pathological features of the cancer

Genetic counseling and diagnostics

Genetic diagnostics can identify causative germline variants. This enables estimation of the likelihood of developing cancer, adapted follow-up or early detection, and the use of specific oncological therapies (e.g. PARP or checkpoint inhibitors). Most tumor risk syndromes follow an autosomal dominant mode of inheritance, i.e. are statistically inherited by half of the offspring regardless of gender. If a tumor risk syndrome is detected in a family, there is the possibility of targeted genetic testing for family members. Afterwards, carriers of the familial variant can be offered adapted preventive measures. In addition to high-quality diagnostics, comprehensive genetic counseling is important. This helps to avoid the negative psychosocial effects of a diagnosis, strengthen the self-efficacy of those affected and ensure ideal management regarding early detection and therapy.