Building consensus for Molecular Tumor Board implementation in Europe: a Delphi procedure

Background: Molecular Tumor Boards (MTBs) integrate molecular and clinical data to guide precision oncology decisions, but their structure remains heterogeneous across Europe. This study developed consensus-based policy recommendations to support their harmonized implementation. Methods: A two-round Delphi process was conducted among 17 European MTB experts. Questionnaire items were derived from two reviews on clinical impact and implementation aspects. Experts rated items on a five-point Likert scale; consensus was defined as a Content Validity Index (CVI) ≥80% agreement (scores 4–5). Results: Across two rounds, 76 items were evaluated; 36 reached consensus, resulting in 15 recommendations across four domains: organizational aspects (n=8), testing (n=3), inclusion criteria (n=2), and clinical aspects (n=2). Key organizational standards include appointing a referent clinician, using standardized digital submission tools, online meeting formats, and decision-support systems. MTBs should be multidisciplinary. For testing, experts agreed that Next Generation Sequencing should be preferred, performed in certified laboratories, with variant interpretation supported by curated databases. Inclusion criteria and clinical aspects prioritize patients with metastatic or rare disease, ECOG 0–2, life expectancy ≥12 weeks, and exhaustion of standard therapies. Conclusions: This Delphi produced 15 recommendations to standardize MTBs across Europe, complementing existing frameworks with practical operational guidance for precision oncology. Public Interest Summary: Cancer treatment is becoming increasingly personalized thanks to new genetic and molecular technologies. Molecular Tumor Boards (MTBs) are expert groups that help health professionals choose the most appropriate treatments by combining genetic test results with clinical information. However, across Europe, MTBs are organized and used in very different ways, which can lead to unequal access and quality of care for patients. This study brought together 17 experts from different European countries to agree on practical recommendations for how MTBs should be heterogeneously organized. Using a structured consensus method, the experts reached 15 recommendations covering organization, testing, inclusion criteria, and clinical aspects. The results highlight the importance of multidisciplinary teamwork, standardized digital tools, high-quality genetic testing, and clear criteria for patient inclusion. These recommendations aim to support more consistent, fair, and effective use of precision cancer technologies across European health systems, ultimately improving patient care and decision-making.