Large bay windows through which a soft light enters, comfortable sofas, unlimited coffee. Sylvie, Marc, Nadine and Ichan* are waiting in the hall of the “Interception” building at the back of Gustave-Roussy, the first European center for the fight against cancer, located in Villejuif (Val-de-Marne). They are not sick, but they have been identified as being at high risk of developing a tumour. The objective of the program in which they have agreed to participate: to prevent them from having, one day, to cross the doors of the huge building made of neighboring organ pipes, where patients suffering from cancer are treated.

“The idea of ​​the concept of “Interception” is to prevent the disease from occurring, or, failing that, to identify it at such early stages that the patient will be cured, without sequelae. is about the prevention of the future: we are not there yet, but we are building everything we need to get there”, explains Dr Suzette Delaloge, oncologist at Gustave-Roussy and project manager. Eventually, all you have to do is complete an online questionnaire to find out your risk and be offered advice or even medication to reduce it, as well as personalized screening. The stakes are immense. Despite progress in treatment, which should further illustrate the congress of the European Society of Medical Oncology being held this weekend in Paris, cancer remains the leading cause of death in France, with approximately 160,000 deaths per year. However, scientists estimate that 75% of people who develop a tumor would be identifiable in previous years as being at high risk of falling ill.

Paradoxically, prevention is not very successful: “Participation in organized screening is collapsing, vaccination against the papillomavirus does not attract, it is quite catastrophic”, regrets Dr Delaloge. Hence the idea of ​​adapting these measures to the real risk of each person, to make them more acceptable. “In the case of breast cancer, the women most at risk would have a mammogram a year, and the others could postpone this examination for several years”, illustrates the geneticist Olivier Caron, member of the “Interception” team.

Sylvie, Marc, Nadine and Ichan were referred here by their doctor because they are heavy smokers – at least one pack a day, for more than thirty years. Their day promises to be busy. Marc, 45, a nightclub manager, tries out the elliptical trainer, which reproduces the movement of running. After a few minutes, he must stop… “We assess their cardiovascular and muscular capacity, to then see how to increase their physical activity on a daily basis”, explains Elodie, the sports coach. While waiting for their turn, Sylvie, Nadine and Ichan answer a questionnaire on their diet. The opportunity to demystify some fake news: no, royal jelly or essential oils do not protect against cancer… Everyone will have a screening scan, and attend a conference on the risks associated with tobacco. At the end of the day, they leave with personalized advice – diet, sport, appointment with a tobacco specialist and calendar of the next scans.

Similar programs exist for breast, colon and mouth cancers. A questionnaire made available to general practitioners in the region allows them to identify, among their patients, those most at risk of developing one of these tumours, often because of their family history, their weight or their medical history. 800 Ile-de-France residents have already taken part. Soon, certain tumors of the blood and of the pancreas will be added. “We only take into account the cancers for which we can propose an action: prevention, screening, or a research program”, specifies Suzette Delaloge. His team is teeming with projects. In the case of pancreatic cancer, which is often detected much too late, participants will wear a blood glucose measuring patch several times a year for a few days. The appearance of type 2 diabetes would indeed be a sign that the pancreas is suffering, which may be linked to a tumour.

In the coming months, other cancer centers, hospitals and clinics will offer a similar service. “We are pioneers, but we need equal access to this type of program throughout the territory. In addition, we need to have a great diversity of participants whose future we can follow, in order to continue to refine our evaluation. risks”, emphasizes Prof. Fabrice Barlesi, Managing Director of Gustave-Roussy. Because it will of course be necessary to measure the impact of the proposed measures, even if these are already all based on validated data.

Scientists are also working to develop new screening tools, such as biomarkers in the blood and in the stool to identify, among smokers, those most at risk of falling ill. Significant inflammation, a drop in immunity, dysregulation of the microbiota could prove to be precursor signals. If this were confirmed, the researchers are already planning to block the tumor process with short-term immunotherapies to restore immunity, or drugs to modify the intestinal flora. “People at high risk present both a favorable context for the emergence of deleterious mutations in their cells and a failing immunity that does not eliminate these mutated cells. We can therefore play on several tables. We will see in the long term which one will be the most effective according to the profile of each”, explains Suzette Delaloge. After precision medicine, it is perhaps the era of precision prevention that is beginning to dawn.

*Names have been changed.