RISKS OF BRAIN-TUMOR FOLLOWING TREATMENT FOR CANCER IN CHILDHOOD - MODIFICATION BY GENETIC-FACTORS, RADIOTHERAPY AND CHEMOTHERAPY

A cohort of 4,400 persons treated for various cancers of childhood in France and the UK was followed up over an extended period to assess ri sks of subsequent brain tumour in relation to the radiotherapy and che motherapy that the children received for their first cancer. Elevated risks of subsequent brain tumours were associated with first central n ervous system (CNS) tumour (two sided p = 0.0002) and neurofibromatosi s (two-sided p = 0.001). There was also elevated brain tumour risk (tw o-sided p = 0.003) associated with ionising radiation exposure, the ri sk being concentrated among benign and unspecified brain tumours. The radiation-related risk of benign and unspecified brain tumours was sig nificantly higher than that of malignant brain tumours (two-sided p le ss than or equal to 0.05); there was no significant change of malignan t brain tumour risk with ionising radiation dose (two sided p > 0.2). In general, there were no strong associations between alkylating agent dose and brain tumour risk, The only significant association between brain tumour risk and alkylating agent dose was in relation to compoun ds used (bleomycin, chloraminophen) that are thought not to deliver su bstantial doses to the brain: the statistical significance of the tren d with dose depended on a single case, and thus must be considered a w eak result. Int. J. Cancer 78:269-275, 1998. (C) British Crown copyrig ht 1998/NRPB-published with the permission of the Controller of Her Ma jesty's Stationery Office.