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MINDACT (Microarray In Node-Negative and 1 to 3 Positive Lymph Node Disease May Avoid Chemotherapy) is a prospective, randomized study comparing the 70-gene signature with the common clinical-pathological criteria in selecting patients for adjuvant chemotherapy in breast cancer with 0 to 3 positive nodes.

Launched and coordinated by BIG under its European Commission supported consortium, TRANSBIG and coordinated by the EORTC, this trial with a target of 6000 patients used microarray technology to better determine which women really need adjuvant chemotherapy.

Results of MINDACT’s pilot phase show that despite its logistical complexity, the trial is collecting high quality data and biological materials for translational research.

Detailed description of MINDACT


If you wish to access MINDACT biological material and genomic/clinical data, please contact Mrs. Sabine Corachan at:

Detailed information can be found in the following documents:

Policy for Access to MINDACT Biological Materials and Data.

Request Form: Biological Materials and/or Data.

Detailed description of MINDACT


Node-negative and 1-3 lymph node positive breast cancer is a cancer that has not or only minimally spread to the surrounding lymph nodes and has a lower risk of recurrence. Patients with this type of cancer are often prescribed chemotherapy, although physicians believe that approximately 15% of them do not require such treatment.

The aim of MINDACT was to evaluate the utility of adding the 70-gene signature MammaPrint® to standard clinico-pathological criteria in order to identify those patients with early-stage breast cancer who can be safely spared adjuvant chemotherapy without this significantly affecting their risk of disease recurrence.


The project partners predicted that using MammaPrint® would result in a more accurate assessment of the risk of recurrence in early breast cancer patients than the usual clinical and pathological assessment.
In particular, they predicted that in 10-20% of the women with node-negative and 1-to-3 node positive breast cancer chemotherapy, and the side-effects that come with it, could be safely avoided.


The study proved its main hypothesis and showed that using MammaPrint® has the potential to change the way doctors and patients make decisions about breast cancer. 
When analysing the data from all 6,693 patients enrolled in MINDACT, the trial showed that taking treatment decisions based on MammaPrint® rather than on the basis of the common clinico-pathological factors led to 14% less chemotherapy being prescribed

Among the 3,356 patients enrolled in the MINDACT trial who were categorised as having a high risk of breast cancer recurrence based on common clinico-pathological criteria (c-High), MammaPrint® identified 1.550 patients as having a low genomic risk.
This would amount to a 46% reduction in chemotherapy prescription.Five-year distant metastasis-free survival for this discordant c-High/g-Low group is in excess of 94 percent, whether patients received chemotherapy or not. Given the very good outcome without chemotherapy, the added value of chemotherapy in absolute numbers is small in these patients (1.5%), suggesting that chemotherapy could be safely omitted.

In short, MINDACT provides the highest level of evidence to show that using MammaPrint® can accurately identify patients who can safely avoid chemotherapy, thereby substantially reducing the prescription of chemotherapy in patients with node-negative and 1-to-3 node positive breast cancer.


Microarray analysis is a technology that reveals the individual genes expressed by a tumour and its potential aggressiveness. The MINDACT microarray test - MammaPrint® - examines 70 breast cancer genes that provide essential information to determine how breast cancer tumours are likely to behave (these genes are NOT hereditary breast cancer genes, but only those from the actual tumour).

The result of the test is dichotomous; the tumour cells are classified as either low or high genomic risk. When the majority of these genes are inactive, the tumour is considered to represent a low risk of recurrence.



Women aged 18–70 years with operable, invasive breast cancer, with 0 to 3 positive lymph nodes, no distant metastases, and whose frozen tumour sample was collected. 

Overall recruitment (completed): 6.693 patients between 2007 and 2011.


The trial is run by the European Organisation for Research and Treatment of Cancer (EORTC), the sponsor, under the Breast International Group (BIG) umbrella, and a great many other partners, both from academia and the private sector, and including the breast cancer patient advocacy network Europa Donna. Agendia is the biotechnology company that developed MammaPrint®.

  • A tissue sample from the patient was sent to the laboratory where it was subjected to both clinical risk assessment, on the basis of clinical and pathological factors using a modified Adjuvant!Online, and genomic risk assessment using the MammaPrint® test.

  • If both methods indicated a low risk of recurrence, chemotherapy was not recommended. If both methods suggested a high risk of recurrence, the patient was advised to have chemotherapy.

  • However, in cases where the tests disagreed, patients were randomly assigned to either be treated on the basis of the results of the clinical assessment, and some were treated on the basis of the results of MammaPrint®.

  • All patients involved in the trial are being closely monitored by doctors throughout the process and for at least 10 years.

  • The over 52,000 samples derived from these patients, including tissue, blood and serum, are stored in a biorepository for long-term storage, enabling future research.

  • Over 11.000 patients were screened between 2007 and 2011.

  • A “pilot” involving the first 800 patients enrolled was completed in 2010, indicating the viability of the trial in spite of its complex logistics.

  • Recruitment of 6.693 patients was completed in July 2011.

  • The primary results were presented on 18 April 2016, during the American Association for Cancer Research Annual Meeting.


112 hospitals in 9 countries are participating in this trial through 7 BIG collaborative groups (EORTC, BOOG, GOIRC, NCRI, SOLTI, Unicancer, WSG)


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), Association Le Cancer du Sein, Parlons-en!, the Brussels Breast Cancer Walk-Run and the American Women’s Club of Brussels, NIF Trust, Deutsche Krebshilfe, the Grant Simpson Trust and Cancer Research UK. This trial was also supported by the EORTC Charitable Trust. Whole genome analysis was provided in kind by Agendia. Total funding: approx. EUR 47 million.


- 70-Gene Signature as an Aid to Treatment Decisions in Early-Stage Breast Cancer, Cardoso F, van't Veer LJ, Bogaerts J, Slaets L, Viale G, Delaloge S, Pierga JY, Brain E, Causeret S, DeLorenzi M, Glas AM, Golfinopoulos V, Goulioti T, Knox S, Matos E, Meulemans B, Neijenhuis PA, Nitz U, Passalacqua R, Ravdin P, Rubio IT, Saghatchian M, Smilde TJ, Sotiriou C, Stork L, Straehle C, Thomas G, Thompson AM, van der Hoeven JM, Vuylsteke P, Bernards R, Tryfonidis K, Rutgers E, Piccart M; MINDACT Investigators, N Engl J Med. 2016 Aug 25;375(8):717-29. doi: 10.1056/NEJMoa1602253. Identifier: NCT00433589


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