From 1975 to 1997, thirty seven newly diagnosed children aged 2 mos. to 14.3 years with diffuse medulla oblongata or pontine tumours were referred to the Centre Léon Bérard. Surgical biopsies were performed in 9 patients. All but one received radiation therapy. The mean dose of radiation was 53 Gy. Thirty two received chemotherapy. All patients died, one from related toxicity, and the rest from progressive disease. Relapses always occurred in the radiotherapy field. Medulla oblongata and pontine tumours would appear to have the worst outcome of all brain stem gliomas and should be separately analysed.