Technical recommendations from a large-scale French Delphi consensus: A step toward European harmonization of ctDNA analysis
Year: 2026
Type: article
Abstract: BACKGROUND: Circulating tumour DNA (ctDNA) testing by liquid biopsy has become a cornerstone of precision oncology, yet technical heterogeneity across laboratories continues to hamper reproducibility and clinical reliability. METHODS: To address this challenge, the Groupe Français de Cytogénétique Oncologique (GFCO) conducted the largest European Delphi consensus initiative to date on technical standardization of ctDNA analysis, involving 39 high-volume molecular platforms (71 % response rate). RESULTS: Using iterative anonymous surveys and live voting, we established 37 recommendations (≥80 % agreement) spanning pre-analytical, analytical, bioinformatics, and post-analytical phases. Key consensus points include mandatory use of unique molecular identifiers (UMIs) with preference for ligation-based incorporation (95-100 %), double centrifugation with high-speed second spin, systematic positive controls mimicking ctDNA characteristics, leukocyte aliquot preservation for clonal haematopoiesis evaluation, and explicit reporting of variant allele frequency, CHIP risk, and limitations of negative results. These recommendations demonstrate more than 90 % alignment with recent ESMO (2022), ELBS (2025), ISLB (2025), and AMP/CAP guidelines while providing more prescriptive, operationally oriented specifications on critical steps (e.g., UMI implementation, plasma storage, centrifugation parameters) that address real-world gaps repeatedly identified in European external quality assessment schemes. CONCLUSIONS: By offering a robust, ready-to-implement framework that complements and refines existing international standards, this consensus paves the way for broader harmonization of ctDNA testing across Europe and beyond, ultimately strengthening confidence in liquid biopsy results for routine diagnostic and theragnostic applications in oncology.
Source: European Journal of Cancer
Authors: Alexandre Harlé, Léa Payen, Alexandra Lespagnol, Nicolas Goardon, Juliette Albuisson, Marie-Christine Etienne-Grimaldi, Anne Pradines, Alexandre Atkinson, Simon Cabello Aguilar, Alain Morel, Etienne Rouleau, Juliette Albuisson, Alexandre Atkinson, Romain Boidot, Simon Cabello Aguilar, Céline Callens, Charline Caumont, Louise-Marie Chevalier, Sophie Cotteret, Clotilde Descarpentries, Julie Dremaux, Marie-Christine Etienne-Grimaldi, Marie-Dominique Galibert-Anne, Nicolas Goardon, Alexandre Harlé, Paul Hofman, Lucie Karayan-Tapon, Ludovic Lacroix, Aude Lamy, Pierre-Jean Lamy, Cédric Lemarechal, Jacqueline Lehmann-Che, Alexandra Lespagnol, Jonathan Lopez, Alain Morel, Jean-Baptiste Oudart, Alexis Overs, Léa Payen, Anne Pradines, Anaïs Pujals, Etienne Rouleau, Isabelle Soubeyran, Gaëlle Tachon, Anne Tallet, Marie-Pierre Wissler
Institutions: Centre National de la Recherche Scientifique, Institut de Cancérologie de Lorraine, CRAN, Université de Lorraine, Hospices Civils de Lyon, Centre Hospitalier Universitaire de Rennes, Centre François Baclesse, Centre Georges François Leclerc, Université Côte d'Azur, Centre Antoine Lacassagne, Laboratoire de Recherche Translationnelle en Oncologie, Institut universitaire du cancer de Toulouse Oncopole, Centre Hospitalier Universitaire de Montpellier, Institut de Cancérologie de l'Ouest, Institut Gustave Roussy, Institut Curie, Centre Hospitalier Universitaire de Bordeaux, Centre Eugène Marquis, Centre Hospitalier Universitaire de Lille, Centre Hospitalier Universitaire Amiens-Picardie, Université de Rennes, Centre Hospitalier Universitaire de Nice, Centre Hospitalier Universitaire de Poitiers, Centre Hospitalier Universitaire de Rouen, Université de Bretagne Occidentale, Université de Bretagne Occidentale, Assistance Publique – Hôpitaux de Paris, Centre Hospitalier Universitaire de Reims, Centre Hospitalier Universitaire de Besançon, Centre Hospitalier Universitaire Henri-Mondor, Hôpitaux Universitaires Henri-Mondor, Institut Bergonié, Centre Léon Bérard, Centre Hospitalier Universitaire de Tours
Language: English
Subfield: Cancer Research
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $4,270
OpenAlex ID: W7161148619