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Breast cancer and fertility

Press release (11/10/2022) 

Breast cancer and fertility
Progress in research is bringing great hope to women who want to have childrenFertilité et cancer

Pink October is breast cancer awareness month. On this occasion, the Jules Bordet Institute is looking at links between breast cancer and fertility. Given the increase in breast cancers and the fact that women want to have children later and later in life, cases of patients diagnosed with breast cancer who do not yet have children but want to conceive are becoming more frequent.  This is why progress in research is so important. To understand the issues, discover the POSITIVE study and the testimony of one female patient. 

More and more cancers and delayed childbearing
You can be diagnosed with breast cancer at any age. At present more than 10,000 women are diagnosed with breast cancer every year in Belgium. The number of women diagnosed with breast cancer is in fact growing while at the same time there is a tendency for women to conceive their first child at a later age.  The result is that more and more women face a breast cancer diagnosis when they do not yet have children but have a strong desire to be pregnant. Faced with this situation there was an absence of any clear scientific answer that could be given to patients: Is it possible to cease treatment without running an excessive risk? Is it possible to conceive a child? Under what conditions? As Professor Martine Piccart, head of Scientific Research at the Jules Bordet Institute, explains "Research linked to pregnancy after breast cancer is limited. Achieving research progress on this subject and obtaining clear answers for all women who want to conceive despite having breast cancer is of capital importance!"

The POSITIVE study    
For all these women who want to have a child, the POSITIVE study is seeking to provide the answers. Conducted by the International Breast Cancer Study Group (IBCSG) under the aegis of the Breast International Group (BIG) in 20 countries, and with the close involvement of the Jules Bordet Institute, the study is monitoring 518 women aged between 30 and 40 with early stage hormonal breast cancer who want to become pregnant. Hormonal breast cancer means that estrogen receptors are present in the cancer cells, acting as "antennae" with the result that cancer cells are fed by estrogens. This is the case for two thirds of women diagnosed with breast cancer. The recommended treatment in this case is hormone therapy plus surgery and radiotherapy and sometimes chemotherapy. Hormone therapy is totally incompatible with pregnancy. The study is therefore seeking to observe the effects of ceasing hormone therapy for 24 months during which the patient can conceive a child and then resume treatment. At this stage of the study, which began in 2014, more than 300 babies have been born. The study is continuing by observing the effects of a long-term (10 years) interruption of hormone therapy. 

The initial results, with a median follow up of 41 months, will be presented at the Congress in San Antonio in the United States in December. 

A topical subject of pertinence to society that affects many women
Sandra is being treated for breast cancer at the Jules Bordet Institute. She explains: "I was diagnosed with breast cancer at the age of 33. As it was caught quite early, I had no doubt that I would recover. What was hardest for me, on the other hand, was fear of not being able to have children. Although it was quite an obstacle course as some of my ovaries had to be frozen, I became pregnant with my first child. Despite a second breast cancer a few years later, I was also able to have a second child. The message I would like to convey to all these women who face the very difficult experience of a cancer is to remain optimistic, positive and believe in science: today there are many solutions for being able to conceive a child, despite the illness." The artist Simona B. sought to express this same message of hope in creating a photographic work in which the stars are the women and children who are fighting or have fought breast cancer.  (Photo attached). A work full of optimism and joy that today has pride of place in a corridor in the area where patients attend for consultations at the Jules Bordet Institute. 

The POSITIVE study is sponsored by the BCSG and has benefitted from major financial support from the Baillet Latour Fund.  

  • About the Breast International Group (BIG)
    The Breast International Group (BIG) is a not- for-profit organisation for academic breast cancer research groups from around the world. It is based in Brussels, Belgium. 

    International cooperation is crucial in achieving significant progress in breast cancer research, avoiding duplication, sharing data, contributing to the most rapid development of the best treatment and improving patients' prospects of recovery. That is why BIG facilitates breast cancer research at international level by encouraging cooperation between its members and other academic networks and by cooperating with the pharmaceutical industry while being careful to retain its independence.

    BIG was founded in 1999 by Dr Martine Piccart and Dr Aron Goldhirsch with the aim of combating the fragmentation of European breast cancer research. Research groups from other parts of the world soon expressed an interest in joining the organisation and, two decades later, BIG has become a network of more than 50 research groups from around the world, united in a shared vision. These entities are attached to several thousand specialised hospitals, research centres and experts in cancerology of international renown in some 70 countries on six continents.   The BIG network is today behind more than 30 clinical studies, either current or being developed. BIG also works closely with the US National Cancer Institute (NCI) and North American breast cancer research groups (National Clinical Trials Network - NCTN). Together they represent a powerful force of integration in the field of breast cancer research. 

    The research carried out by BIG is in part supported by its philanthropic unit, known as  BIG against breast cancer, a name that is used to interact with the general public and donors and to raise funds for purely academic breast cancer research programmes and trials carried out by BIG

    You will find more information at