Hereditary colorectal carcinoma. Current genetic diagnostics

Background: Approximately 5% of patients with colorectal carcinoma (CRC) have a monogenic hereditary tumor syndrome. These include Lynch syndrome and various gastrointestinal polyposis syndromes. Objective: The current possibilities of molecular genetic diagnostics are presented. Material and methods: Selective literature search and own expertise. Results: The new methods of high-throughput sequencing enable effective and comprehensive genetic diagnostics but also pose a challenge for the interpretation of the findings and counselling. The indications are usually based on clinical suspicion criteria. Other diagnostic entry points are conspicuous molecular pathological findings based on therapeutic indications and secondary findings. Conclusion: The identification of a causative germline mutation in an affected individual enables the correct differential diagnosis and subsequent predictive testing of asymptomatic at-risk relatives. This is of high clinical relevance as effective preventive measures exist.