On Monday, December 1, 2025, the French National Registry of Childhood Cancers (RNCE) held its annual investigators’ meeting at the Faculty of Medicine of Université Paris Cité – Villemin campus (Paris). This event brought together investigators involved in the collection of incidence data on childhood and adolescent cancers across metropolitan France and the overseas departments.

The day opened with an introduction by Brigitte Lacour, who presented the general context, recent news from the RNCE, its history, and future perspectives. This session provided an opportunity to retrace the development of the registry and to highlight the importance of the collective work carried out since its creation.

The morning continued with a review of the registry’s organization and data collection methods, which are essential to ensuring the quality and consistency of the data. General data collection guidelines were presented, along with specific procedures for hematological malignancies, solid tumors, and treatment-related data. These discussions helped harmonize practices and address investigators’ questions.

The afternoon was devoted to presentations of scientific work conducted using RNCE data, including GEOCAP environmental case–control studies based on the geolocation of children’s and adolescents’ residences, and the COHOPER follow-up cohort. These presentations illustrated the richness of the collected data and their major contribution to research and knowledge on childhood and adolescent cancers.

This annual meeting was also marked by a special moment on the occasion of the retirement of Brigitte Lacour, Director of the Childhood Solid Tumor Registry since its creation in 2000. A key figure of the RNCE, she has made a major contribution to the structuring, development, and national and international recognition of the registry. The entire team wishes to acknowledge her scientific commitment, constant dedication, and decisive role in ensuring the quality of the data produced by the RNCE. The registry extends its sincerest thanks to her.

A Collective Dynamic in the Service of Children’s and Adolescents’ Health

This day highlighted the crucial role of investigators in the functioning of the RNCE and the need to maintain a strong collaborative dynamic, which is essential for epidemiological surveillance and research on childhood and adolescent cancers.