The long-term results of the MINDACT (EORTC 10041/BIG3-04) study were presented today in the ASCO virtual meeting. MINDACT tests the 70-gene signature MammaPrint to help identifying breast cancer patients who would do not need adjuvant chemotherapy. In 2016, the results of the primary endpoint (distant metastasis free survival (DMFS)) at 5 years median follow up were presented. Dr Fatima Cardoso, the principle investigator of the study, presented the updated results with 8.7 years of median follow-up, with more than 90% of patients followed for at least 5 years. 6693 patients were enrolled in the randomised MINDACT study between 2007-2011. The DMFS was assessed at 5 years for 644 clinical high and genomic low risk patients who were randomised to follow the genomic risk assessment and received no chemotherapy. In addition, a secondary analysis was conducted to evaluate DMFS and overall survival in the same population of clinical high and genomic low population depending on whether chemotherapy was administered or not.
The present analysis confirms that MINDACT is a positive de-escalation study, as the primary DMFS endpoint at 5 years is continually met in clinical high and genomic low risk patients who receive no chemotherapy. The outcome of the “intention to treat” population are shown in the table below.
At 8 years, the estimated DMFS gain for chemotherapy administration in Clinical-High/Genomic-Low is 2.6% and must be balanced with the treatment’s harmful side effects.
A subgroup analyses was performed regarding the effect of chemotherapy per age group. This analysis showed that: a) omitting chemotherapy in Clinical-High/Genomic-Low postmenopausal women continues to be safe, (DMFS gain 0.2% ± 2.3%), and a fully preserved performance of MammaPrint to forego adjuvant chemotherapy is demonstrated; b) in premenopausal women the difference seen might be clinically relevant (DMFS gain 5% ± 2.8%); importantly, this effect may possibly be related to chemotherapy-induced ovarian function suppression.
“The present analysis clearly proves that chemotherapy can safely be avoided for postmenopausal women, classified as high risk of relapse by traditional clinico-pathological factors, but with a MammaPrint test of low risk, confirming the clinical utility of this genomic test, ” said Dr Fatima Cardoso, Principal Investigator of the Study and Director of the Breast Unit at the Champalimaud Clinical Centre, Lisbon, Portugal.
MINDACT was supported by grants from the European Commission Framework Programme VI (FP6-LSHC-CT-2004-503426, “TRANSBIG Network of Excellence”), the Breast Cancer Research Foundation, the U.S. National Cancer Institute, the European Breast Cancer Council-, Pharmaceutical/Biotech Company, U.S. National Institutes of Health
- Session Type: Oral Abstract Session
- Session Title: Breast Cancer—Local/Regional/Adjuvant
- Track: Breast Cancer—Local/Regional/Adjuvant
- Subtrack: Adjuvant Therapy
- Abstract #: 506
- Clinical Trial Registry Number: NCT00433589
- Citation: J Clin Oncol 38: 2020 (suppl; abstr 506)
- DOI: 10.1200/JCO.2020.38.15_suppl.506
Research support: Funding
MINDACT was supported by grants from the European Commission Framework Programme VI (FP6-LSHC-CT-2004-503426, “TRANSBIG Network of Excellence”), the Breast Cancer Research Foundation, Novartis, F. Hoffman La Roche, Sanofi-Aventis, Eli Lilly, Veridex, the U.S. National Cancer Institute, the European Breast Cancer Council-Breast Cancer Working Group (BCWG grant for the MINDACT biobank), the Jacqueline Seroussi Memorial Foundation (2006 JSMF award), Prix Mois du Cancer du Sein (2004 award), Susan G. Komen for the Cure (SG05-0922-02), Fondation Belge Contre le Cancer (SCIE 2005-27), Dutch Cancer Society (KWF), The Netherlands Genomics Initiative – Cancer Genomics Centre (2008-2012), Association Le Cancer du Sein, Parlons-en!, the Brussels Breast Cancer Walk-Run and the American Women’s Club of Brussels, NIF Trust, German Cancer Aid, the Grant Simpson Trust and Cancer Research UK, La Ligue Nationale Contre Le Cancer. This trial was also supported by the EORTC Cancer Research Fund. Whole genome analysis was provided in kind by Agendia.
Role of the funding sources
The funders had no role in study design, data collection, data analysis, data interpretation, or writing of the report. The corresponding author had full access to all the data in the study and had final responsibility for the decision to submit for publication.
We are grateful to all patients and families who participated in this study.
We are grateful to the European Commission Sixth Framework Programme (FP6-LSHC-CT-2004-503426), the European Community Seventh Framework Programme (HEALTH-F2-2009-223175 to the Collaborative Oncological Gene-environment Study), the Breast International Group (BIG) AISBL, F. Hoffmann-La Roche, Novartis, Sanofi-Aventis, for supporting this independent EORTC Study.
Special thanks to:
All national coordinating centers and BIG Groups participating in MINDACT (EORTC-BCG, GOIRC, NCRI-BCSG, SOLTI, UNICANCER-UCBG, WSG).
Steering Committee members: Karen Benn, Jan Bogaerts, Fatima Cardoso, Eva Ciruelos, Sabine Corochan, Julia Cuny, Lorena de la Pena, Suzette Delaloge, Mauro DeLorenzi, Aleksandra Dudek-Peric, Inge Eekhout, Oleg Gluz, Vassilis Golfinopoulos, Theodora Goulioti, Nadia Harbeck, Valérie Hilal, Susan Knox, Jerome Lemonnier, Michał Ławniczak, Luca Marini, Erika Matos, Peppi Morales, Kirsten Murray, Urlike Nitz, Rodolfo Passalaqua, Martine Piccart, Jolanda Remmelzwaal, Isabel Rubio, Emiel Rutgers, Mahasti Saghatchian, Leen Slaets, Christos Sotiriou, Carolyn Straehle, Mark Straley, Nathalie Theron, Alastair Thompson, Konstantinos Tryfonidis, Renata Todeschini, Milanka Urunkar, Laura van ’t Veer, Giuseppe Viale.
Fellows: Kim Aalders, Jacques Bines, Philippe Bedard, Ivana Bozovic, Sofia Braga, Carlos Castaneda, Aleksandar Celebic, Camelia Colichi, Carmen Criscitiello, Lissandra Dal Lago, Gaston Demonty, Caroline Drukker, Fei Fei, Michela Lia, Sherene Loi, Stella Mook, Camilo Moulin, Roman Sreseli, Gustavo Werutsky.
EORTC & BIG Project and Data Managers: Sabine Corachan, Aleksandra Dudek-Peric, Lorraine Wheeler, Nicolas Dif, Giovanna Rizzetto, Melanie Beauvois, Livia Meirsman, Hilde Breyssens, Nuria Decker, Kristel Engelen, Anita Akropovic, Jillian Harrison, Frederic Henot, Miet Celis, Britt De Jongh, Inge Delmotte, Valéry Daubie, Roel Goossens, Nils Helsen, Laetitia Hourt, Sven Janssen, Virginie Soete, Kaat Vansevenant, Catherine Hermans.
All the many academic institutions and collaborators participating in TRANSBIG as well as the scientific or logistical support from Guus Hart, SIB, IEO, Adjuvant!Online, Agendia (Guido Brink, Arno Floore, Bernhard Sixt, and all team), IBBL, IDDI (Marc Buyse), and World Courier