Breast International Group

The Breast International Group, commonly known as BIG, was a Belgian not-for-profit organisation created to coordinate international academic research in breast cancer. Its roots lay in a collaborative framework proposed during the early 1990s by oncologists Martine Piccart and the late Aron Goldhirsch. The initiative was developed during the mid-1990s and became a Belgian legal entity in 1999, with headquarters in Brussels. BIG was designed to address fragmentation in breast cancer research. Rather than operating as a conventional pharmaceutical company or commercial clinical-research contractor, it brought together independent academic research groups to develop and conduct large, multinational studies. Its network enabled investigators to share scientific ideas, recruit patients across borders, reduce duplication, collect biological samples, and evaluate questions that were clinically important but not always commercially attractive. Trials could be conducted with pharmaceutical-industry partners, but BIG's operating principles emphasized academic control of study data, scientific independence, patient interests, and publication of results regardless of outcome. At its peak, BIG connected almost 60 academic research groups across Europe, Canada, Latin America, Asia, and Australasia. Its projects involved several thousand hospitals and research centres and included cooperation with the United States National Cancer Institute and the NCI's National Clinical Trials Network. The organisation's work covered early and metastatic breast cancer, different biological subtypes, treatment de-escalation, hereditary disease, male breast cancer, older patients, and patient-centred survivorship questions. BIG-associated studies helped influence breast cancer treatment and clinical guidelines. BIG 1-98 contributed evidence supporting aromatase inhibitors for hormone-receptor-positive disease. The SOFT and TEXT trials informed endocrine-treatment decisions for premenopausal women. HERA and APHINITY examined trastuzumab-based treatment for HER2-positive breast cancer, while MINDACT provided evidence that genomic testing could help some women with early breast cancer avoid chemotherapy. OlympiA evaluated adjuvant olaparib in patients with high-risk, BRCA-mutated, HER2-negative early breast cancer. Other programmes, including POSITIVE, AURORA, EXPERT, and the International Programme of Breast Cancer in Men, addressed questions involving pregnancy, metastatic disease biology, radiotherapy, and under-researched patient groups. The organisation also coordinated or participated in European Commission-supported programmes such as TRANSBIG, EURECA, INTEGRATE, and Path-for-young. Later operating support included the BIG-SCOPE and BIG-SPARK grants. BIG's philanthropic unit, BIG against breast cancer, raised funds for academic trials and research programmes that were less likely to receive commercial support. Patient involvement became a formal part of BIG's research model. Early cooperation with Europa Donna helped bring patient representatives into study steering committees, including the MINDACT programme. In 2019, BIG established a Patient Partnership to support meaningful involvement of people affected by breast cancer in study design and conduct. Patient representatives were subsequently given seats on the Executive Board. Martine Piccart chaired BIG for more than two decades. In its final years, David Allan Cameron chaired the organisation's Executive Board, while Hans Wildiers served as president of BIG against breast cancer. In December 2025, BIG announced that prolonged financial and economic pressures had led its Executive Board to approve collective redundancies and the closure of the legal entity by the end of 2026. The pressures cited included reduced grants and subsidies, declining study-related income, weaker fundraising returns, and wider economic and geopolitical difficulties. BIG stated that responsibilities for ongoing studies would be transferred to other partners so that research continuity, study integrity, and support for participating patients and investigators could be maintained.

The Breast International Group emerged from concerns that breast cancer research was too fragmented across national and institutional boundaries. During the early 1990s, oncologists Martine Piccart and Aron Goldhirsch promoted a framework in which academic investigators could meet regularly, compare emerging evidence, coordinate research questions, and conduct trials across multiple countries. The initiative was developed during the mid-1990s and incorporated as a Belgian legal entity in 1999, establishing its headquarters in Brussels. BIG's central contribution was organisational rather than commercial. It created a mechanism through which independent academic groups could collaborate on studies requiring large patient populations, long follow-up, international recruitment, and shared scientific infrastructure. Its governance and research policies sought to preserve academic control of study data and ensure that trial results would be published according to scientific standards, whether or not the findings supported a sponsor's expectations. Commercial partnerships were possible, but scientific independence and the interests of patients remained core principles. The network expanded from a European initiative into a global breast cancer research organisation. At its peak, it connected almost 60 academic groups across Europe, Canada, Latin America, Asia, and Australasia, with several thousand hospitals and research centres participating in its studies. BIG also worked with the United States National Cancer Institute and the NCI's National Clinical Trials Network. Many studies collected biological specimens, allowing clinical trials to support later translational and molecular research. Its portfolio covered hormone-receptor-positive, HER2-positive, triple-negative, metastatic, hereditary, and early breast cancer. BIG 1-98 helped establish the role of aromatase inhibitors in hormone-receptor-positive disease. SOFT and TEXT shaped treatment discussions for premenopausal women. HERA and APHINITY investigated trastuzumab-based treatment in HER2-positive breast cancer. MINDACT examined whether genomic testing could identify patients who might safely avoid chemotherapy. OlympiA studied adjuvant olaparib in patients with high-risk early breast cancer carrying BRCA mutations. Other academic programmes examined temporary interruption of endocrine therapy for pregnancy, molecular evolution in metastatic disease, possible omission of radiotherapy, male breast cancer, and treatment questions affecting older patients. BIG also participated in European Commission-supported projects, including TRANSBIG, EURECA, INTEGRATE, and Path-for-young, and later received operating support through BIG-SCOPE and BIG-SPARK. Its philanthropic arm, BIG against breast cancer, helped fund research questions that were important to patients but not necessarily commercially attractive. Patient participation developed over time. BIG worked with Europa Donna at an early stage to involve patients in study steering committees, with MINDACT being an important example. In 2019, the organisation created a formal Patient Partnership. Patient representatives were later given two places on the Executive Board, reflecting a shift toward conducting research with patients rather than merely for them. Martine Piccart chaired BIG for more than 20 years. In its final period, David Allan Cameron chaired the Executive Board and Hans Wildiers served as president of BIG against breast cancer. In December 2025, BIG announced that prolonged financial pressure, declining grant and study-related income, reduced fundraising returns, and broader economic and geopolitical conditions had made a sustainable long-term future impossible. It planned collective redundancies and closure of the legal entity by the end of 2026. Responsibilities for active studies were to be transferred to other partners, with the stated aim of protecting research continuity and participating patients. The planned closure marked the end of more than 25 years of international academic coordination led by BIG.

• 2025

  Closure announced

  [1]Breast International Groupen.wikipedia.org

  BIG announced planned collective redundancies and the closure of its legal entity by the end of 2026, with ongoing studies expected to move to other partners.

• 2019

  Patient Partnership established

  [1]Breast International Groupen.wikipedia.org

  BIG created a formal programme to involve people affected by breast cancer in research design and conduct.

• 1999

  BIG becomes a Belgian legal entity

  [1]Breast International Groupen.wikipedia.org

  The organisation was formally established as a Belgian not-for-profit entity and headquartered in Brussels.

• 1990

  Collaborative framework proposed

  [1]Breast International Groupen.wikipedia.org

  Martine Piccart and Aron Goldhirsch proposed a new international model for academic breast cancer collaboration during the early 1990s.

A scientifically independent, patient-oriented international coordinator of academic breast cancer research, focused on large collaborative trials and clinically important questions across the disease spectrum.

• Clinical trial

  BIG 1-98

  A major academic trial evaluating endocrine-treatment strategies for postmenopausal women with hormone-receptor-positive early breast cancer. Its findings contributed to the adoption of aromatase inhibitors as an important treatment option in this setting.

• Clinical trial

  HERA

  An international study of trastuzumab after standard treatment for HER2-positive early breast cancer. The trial generated evidence that supported trastuzumab-based treatment and helped improve outcomes for eligible patients.

• Clinical trial

  MINDACT

  A trial examining whether the MammaPrint genomic test could help identify women with early breast cancer who might safely avoid chemotherapy. Its results supported more selective use of chemotherapy for some patients with clinically high-risk but genomically low-risk disease.

• Clinical trial

  APHINITY

  A large study evaluating dual HER2 blockade with trastuzumab and pertuzumab in early HER2-positive breast cancer. The programme contributed evidence on how intensified anti-HER2 treatment could improve outcomes for selected patients.

• Clinical trial

  OlympiA

  An international study of adjuvant olaparib for patients with high-risk, HER2-negative early breast cancer and inherited BRCA mutations. The results showed a clinically meaningful reduction in the risk of death and helped establish a role for adjuvant PARP-inhibitor treatment in this population.

• Clinical trial

  POSITIVE

  A patient-centred study investigating whether selected women with hormone-receptor-positive breast cancer could temporarily interrupt endocrine therapy to attempt pregnancy without compromising treatment goals.

• Molecular research programme

  AURORA

  A molecular screening and research programme focused on understanding how metastatic breast cancer evolves. Its purpose was to identify biological insights that could support the development of better future treatments.

• Clinical trials

  SOFT and TEXT

  These linked studies examined endocrine-treatment strategies for premenopausal women with hormone-receptor-positive breast cancer. Their findings influenced decisions concerning ovarian suppression and the choice of endocrine therapy.

• BIG against breast cancer

  International

  BIG against breast cancer was the organisation's philanthropic unit. It raised funds for academic trials and research programmes addressing patient-centred questions that were not always eligible for commercial financing.

  Outcome. Supported the broader BIG research portfolio and helped sustain studies focused on clinically important but commercially underfunded questions.

  Source

• 2025

  Decision to close the organisationStrategy

  Background

  BIG reported prolonged financial and economic pressure, including reduced availability of grants and subsidies, declining study-related income, lower fundraising returns, and wider economic and geopolitical challenges.

  Action taken

  The Executive Board decided to proceed with collective redundancies, cease operations, and close BIG as a legal entity by the end of 2026.

  Aftermath

  BIG arranged for scientific and operational responsibility for ongoing studies to move to other partners in order to preserve study integrity and continued support for patients and investigators.

  Source

1. 1Breast International Groupen.wikipedia.org
2. 2The Breast International Group: a new spirit of collaboration in breast cancer research for the new millenniumdoi.org
3. 3Overcoming Barriers to Clinical Trials Cooperation: The Breast International Group Exampledoi.org
4. 4The Breast International Group (BIG) Patient Partnershipdoi.org
5. 5BIG against breast cancerbigagainstbreastcancer.org