Clinical relevance of molecular diagnostics in gastrointestinal (GI) cancer: European Society of Digestive Oncology (ESDO) expert discussion and recommendations from the 17th European Society for Medical Oncology (ESMO)/World Congress on Gastrointestinal Cancer, Barcelona

Background and scope In the epoch of precision medicine and personalised oncology, which aims to deliver the right treatment to the right patient, molecular genetic biomarkers are a topic of growing interest. The aim of this expert discussion and position paper is to review the current status of various molecular tests for gastrointestinal (GI) cancers and especially considering their significance for the clinical routine use. Methodology Opinion leaders and experts from diverse nationalities selected on scientific merit were asked to answer to a prepared set of questions about the current status of molecular diagnostics in different GI cancers. All answers were then discussed during a plenary session and reported here in providing a well-balanced reflection of both clinical expertise and updated evidence-based medicine. Results Preselected molecular genetic biomarkers that are described and disputed in the current medical literature in different GI cancers were debated, and recommendations for clinical routine practice were made whenever possible. Furthermore, the preanalytical variations were commented and proposals for quality controls of biospecimens were made. Conclusion The current article summarises the recommendations of the expert committee regarding prognostic and predictive molecular genetic biomarkers in different entities of GI cancers. The briefly and comprehensively formulated guidelines should assist clinicians in the process of decision making in daily clinical practice.