Community-based research drives innovation in major fields of public health, HIV/AIDS being the most emblematic example (Demange, Henry & Préau, 2012), and hepatitis. However, this type of research appears to be more difficult to develop in certain specific diseases, such as cancer (Shankand, Saïas & Friboulet, 2009). This article proposes various approaches concerning current citizen mobilization in relation to cancer research, including potential new levers to the development of participative and community-based research based on the recent creation of the Seintinelles platform, designed to federate researchers and citizens concerned by the problem of cancer. This reflection will be supported by more global issues concerning health democracy.