A hereditary tumor syndrome is suspected if there is a high incidence of cancer in a family and/or tumors also occur at a younger age. First-degree relatives of patients with a hereditary tumor disease have an increased risk of also developing a tumor and receive recommendations for a suitable screening program. Hereditary tumor diseases include, for example, hereditary colorectal cancer without polyposis (Lynch syndrome), various polyposis syndromes, hereditary stomach cancer, breast and ovarian cancer or syndromes with a broad tumor spectrum, such as Li-Fraumeni syndrome.