Radiotherapy management of paediatric cancers with synchronous metastasis.

Cancer in childhood represent 1% of all the new diagnosed cancers. About 30% of children with cancer receive radiation therapy, representing about 600 to 700 patients per year in France. As a consequence, paediatric cancers with synchronous metastasis is a very rare situation in oncology, with usually poor standard of care. However, considerable efforts are made by paediatric oncology scientific societies to offer trials or treatment consensus despite these rare situations. The article proposes to synthesize the radiotherapy management of both primary tumour and synchronous metastasis in the most "common" childhood or adolescent cancers.