Unique dataset sheds new light on long-term survival in invasive breast cancer

How do treatments and socio-economic conditions affect the long-term survival chances of women with breast cancer?

October 1, 2025

That is one of the central questions in the doctoral research of Eva Kimpe, affiliated with the Interuniversity Centre for Health Economics Research (I-CHER) and the Research Centre for Digital Medicine (Vrije Universiteit Brussel).

For this study, Kimpe was able to link three national databases to map the long-term effects after a breast cancer diagnosis: the Belgian Cancer Registry (BCR), the InterMutualistic Agency (IMA), and the Crossroads Bank for Social Security (CBSS). This unique dataset brings together information on medical pathways, healthcare costs, socio-economic background, and survival status of all Belgian women diagnosed with breast cancer in 2010. By combining this information, it became possible to conduct analyses at the individual patient level rather than relying only on regional averages or estimates.

The main question was to what extent women, after treatment for breast cancer, experience a life expectancy comparable to that of the general population of the same age. The results are striking. “Age at diagnosis proves to be an important factor. We observed that the older a woman is at diagnosis, the less likely it is that her life expectancy will return to the level of women of the same age without breast cancer,” says Eva Kimpe. The type of treatment also plays a crucial role. “Women who received the then ‘gold standard’ treatment — a pathway consisting of surgery followed by chemo- and radiotherapy — had the greatest chance of seeing their survival return to the level of the general population.” Socio-economic factors also proved decisive. “Women who, at the time of diagnosis, were entitled to increased reimbursement — an indicator of financial vulnerability — were less likely to fully recover in the long term compared with women without this status,” Kimpe continues.

The study thus shows that health inequality continues to play an important role even within cancer care. “Our results highlight how important it is for policy to continue focusing on accessible care and targeted screening programs, so that especially women in vulnerable positions are diagnosed in time and given better chances of recovery,” says Prof. Koen Putman {i}.

“We must, however, emphasize that the results apply to women diagnosed in 2010,” says Prof. Dr. Mark De Ridder {ii}. “New treatments, such as immunotherapy and high-precision radiotherapy, will undoubtedly also have an impact in the future,” concludes Prof. De Ridder.

Because the dataset is continuously updated, it will also be possible to map out 15- and 20-year survival in the future.

Reference:

Eva Kimpe, Sven Van Laere, Sara-Lise Busschaert, Max Lelie, Ellen Tisseghem, Xavier Rygaert, Kurt Barbé, Pieter Cornu, Mark De Ridder, Koen Putman, Factors associated with long-term survival of invasive breast cancer patients in Belgium: a population-based cohort study, International Journal of Epidemiology, Volume 54, Issue 4, August 2025, dyaf123, https://doi.org/10.1093/ije/dyaf123

Contact:

Eva Kimpe: +32 494 70 15 47, Eva.Kimpe@vub.be

Prof. Dr. Koen Putman[i]: Koen.Putman@vub.be

Prof. Dr. Mark De Ridder [ii]: Mark.DeRidder@uzbrussel.be

{i} Full Professor of Health Services Research and Dean of the Faculty of Medicine and Pharmacy
{ii} Full Professor of Radiotherapy at the Faculty of Medicine and Pharmacy and CEO of UZ Brussel