[Combined chemoradiotherapy of tumors in the child]

The high chemosensitivity of pediatric tumors along with their natural propensity for an early distant dissemination have stimulated the interest for chemo-radiation combinations in children since the mid 50s. Following the early experiments in nephroblastomas on the interaction of Actinomycin-D and radiotherapy, multiple national and international studies have been conducted since the mid 70s with considerable success: nowadays most pediatric tumors enjoy a long term survival in excess of 70%. Like their adult counterparts, these associations aim to induce an early control of the primary tumor and distant spreading (spatial cooperation) but also, more specifically in children, to limit the toxicity on normal tissues when treatment intensity can be further reduced. The association of an initial chemotherapy followed by local radiation at a dose and in a volume adapted to the response to chemotherapy along with associated prognostic factors has become widely tested in national and international studies conducted in Hodgkin's disease, Ewing's sarcoma, medulloblastomas, and brain tumors in the very young. Conversely, concomitant associations have remained limited to high-risk subgroups (parameningeal rhabdomyosarcomas for example) due to their potential hazards.