The aim of this study was to investigate growth and final height in young adults after therapy for malignant diseases. Final height and weight was studied in 50 long-term survivors (LTS) of childhood cancer (aged 17-31 years; 30 men, 20 women) 3-18 years after treatment for malignant diseases (7 acute lymphoblastic leukemia, 20 lymphoma, 8 sarcoma, 15 malignant central nervous system [CNS] tumours). None of the LTS had been treated with growth hormone (GH). A decrease in final height SDS (Standard deviation score) occurred in both LTS of malignant CNS tumours (median height SDS at diagnosis, 0.3; range, -0.9 to 2.2; median final height SDS, -1.3; range, -3.9 to 1.9; p < 0.01) and LTS of lymphoma (p < 0.05) or leukemia (p < 0.05). However, only LTS who received cranial (p < 0.05) or craniospinal (p < 0.001) irradiation (XRT) exhibited reduced final heights. LTS who had received XRT not involving the CNS or had received no XRT at all presented no reduction in final height. LTS of CNS tumours treated with high craniospinal XRT doses (24 to 56 Gy) reached lower (p < 0.01) final heights when compared with LTS of leukemia who received lower cranial XRT doses (18 to 24 Gy). Final height SDS correlated with chronological age at initiation of therapy (p < 0.05). No correlation was found between the cumulative doses of applied chemotherapeutic agents and the final height of LTS. During follow-up LTS developed an increase in weight for height index (WFH) which occurred independent of XRT. In conclusion, cranial and craniospinal XRT especially in young children with malignancies resulted in a decrease in final height SDS. As 6 of 15 LTS of malignant CNS tumours exhibited a final height SDS below -2 SD, analysis of pituitary function and substitution of GH after diagnosis of GH deficiency should be considered for these patients at a young age. Others factors not directly related to XRT are responsible for the increased risk for obesity in LTS of childhood cancer.