[Risk of a second malignant neoplasm after successful treatment of a malignant tumour in children (author's transl)].

One boy, given radiotherapy and cytostatic drugs for a rhabdomyosarcoma died nine years later of acute leukaemia. A girl, who had received radiotherapy for an inoperable suprasellar tumour and also given cytostatic drugs, fell ill seven years later with a glioblastoma. Among a total of 750 children with malignant neoplasm observed by the authors, a permanent cure rate of about 50% is to be expected among about 300 children treated recently. If this rate applies to the entire Federal Republic of Germany, about 1,000 children are likely to be cured annually. In these circumstances it is likely that 80-160 children treated in any one year will develop a second neoplasm or leukaemia 20 years later, most commonly as a late sequela of the treatment.