Solutions for optimal care and research for children and adolescents with extremely rare cancers developed within the Joint Action for Rare Cancers (JARC)

Very rare cancers in children and adolescents pose a unique challenge for optimal care and research. Due to their rarity and diversity, there is a lack of standardized treatments and limited data to guide clinical decision-making. This paper aims to provide solutions for addressing these challenges through a multidisciplinary approach involving clinicians, researchers, and patient advocates. In recent years, members of the European Cooperative Study Group for Paediatric Rare Tumors (EXPeRT) and members of the European Society of Pediatric Oncology (SIOPE) clinical council worked within the EU Joint Action on Rare Cancers (JARC) and the Paed Can European Reference Network (ERN) on solutions to improve the care and research in the field. This includes a better classification, more financial resources, higher awareness and support by stakeholders, an international database, as well as harmonized diagnostic and therapeutic guidelines. Further research projects in the field of molecular biology, a better collaboration between medical oncologists and pediatricians, and a general strategy to facilitate access to modern therapies are urgently needed.