[Gastrointestinal polyposis syndromes].

backgroundGastrointestinal polyposis syndromes are the second most common cause of hereditary colorectal carcinomas after Lynch syndrome (hereditary non-polyposis colon cancer, HNPCC). The detection of a causal germline mutation in an affected family member serves for differential diagnosis, assessment of the recurrence risk and predictive testing of healthy individuals at risk.

objectivesThe present article aims to provide an overview of the differential diagnosis of different gastrointestinal polyposis syndromes based on the endoscopic findings, polyp histology, extraintestinal phenotype and molecular genetic diagnostics. MATERIALS AND

methodsThe present article is based on a literature search on gastrointestinal polyposis syndromes.

resultsIn addition to familial adenomatous polyposis (FAP), there are further subtypes of adenomatous polyposis that can often only be distinguished by the detection of a causative germline mutation and are sometimes associated with different extracolonic manifestations. In hamartomatous polyposis syndromes, the clinical overlaps often cause differential diagnostic problems. Serratated polyposis syndrome is possibly the most frequent polyposis syndrome, although its cause is currently largely unexplained.

conclusionsEarly detection and correct classification of polyposis is crucial for adequate prevention and therapy. Access to multidisciplinary expert centres is useful for the care of families.