Technical recommendations from a large-scale French Delphi consensus: A step toward European harmonization of ctDNA analysis
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.
Related
- French validation of the short version of the ASA questionnaire: An exploration of the socio-technical imaginaries and cosmology of Socially Interactive Agent evaluation
- Expert Consensus-Based Clinical Practice Guidelines for Care and Weaning Procedures in Tracheostomized ICU Patients after Invasive Mechanical Ventilation: A Joint Statement by the Intensive Care Physiotherapy Society (SKR) and the French Intensive Care Society (SRLF)
- The Management of Type 1 Diabetes in Adults. The Updated 2026 Consensus Report by the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD)
- [Translation into French and republication of: "French recommendations for the use of Imaging in Giant Cell Arteritis"].
- The management of type 1 diabetes in adults. The updated 2026 consensus report by the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD)
BibTeX
@article{harle2026technical,
title = {{Technical recommendations from a large-scale French Delphi consensus: A step toward European harmonization of ctDNA analysis}},
author = {Alexandre Harlé and Léa Payen and Alexandra Lespagnol and Nicolas Goardon and Juliette Albuisson and Marie-Christine Etienne-Grimaldi and Anne Pradines and Alexandre Atkinson and Simon Cabello Aguilar and Alain Morel and Etienne Rouleau and Romain Boidot and Céline Callens and Charline Caumont and Louise-Marie Chevalier and Sophie Cotteret and Clotilde Descarpentries and Julie Dremaux and Marie-Dominique Galibert-Anne and Paul Hofman and Lucie Karayan-Tapon and Ludovic Lacroix and Aude Lamy and Pierre-Jean Lamy and Cédric Lemarechal and Jacqueline Lehmann-Che and Jonathan Lopez and Jean-Baptiste Oudart and Alexis Overs and Anaïs Pujals and Isabelle Soubeyran and Gaëlle Tachon and Anne Tallet and Marie-Pierre Wissler},
journal = {European Journal of Cancer},
year = {2026},
month = oct,
doi = {10.1016/j.ejca.2026.116791},
url = {https://hal.science/hal-05693316v1},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Technical recommendations from a large-scale French Delphi consensus: A step toward European harmonization of ctDNA analysis
AU - Alexandre Harlé
AU - Léa Payen
AU - Alexandra Lespagnol
AU - Nicolas Goardon
AU - Juliette Albuisson
AU - Marie-Christine Etienne-Grimaldi
AU - Anne Pradines
AU - Alexandre Atkinson
AU - Simon Cabello Aguilar
AU - Alain Morel
AU - Etienne Rouleau
AU - Romain Boidot
AU - Céline Callens
AU - Charline Caumont
AU - Louise-Marie Chevalier
AU - Sophie Cotteret
AU - Clotilde Descarpentries
AU - Julie Dremaux
AU - Marie-Dominique Galibert-Anne
AU - Paul Hofman
AU - Lucie Karayan-Tapon
AU - Ludovic Lacroix
AU - Aude Lamy
AU - Pierre-Jean Lamy
AU - Cédric Lemarechal
AU - Jacqueline Lehmann-Che
AU - Jonathan Lopez
AU - Jean-Baptiste Oudart
AU - Alexis Overs
AU - Anaïs Pujals
AU - Isabelle Soubeyran
AU - Gaëlle Tachon
AU - Anne Tallet
AU - Marie-Pierre Wissler
PY - 2026
DA - 2026/10/16
JO - European Journal of Cancer
DO - 10.1016/j.ejca.2026.116791
UR - https://hal.science/hal-05693316v1
AB - 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.
SN - 0959-8049
ER -