Final height and insulin-like growth factor-1 in children with medulloblastoma treated with growth hormone.

PURPOSE: Medulloblastoma is a highly malignant childhood brain tumor. Survival from medulloblastoma is increasing. This study was performed to examine growth outcomes, insulin-like growth factor-1(IGF-1), and response to growth hormone (GH) treatment in children with medulloblastoma.
METHODS: Retrospective analysis of 34 children treated with GH for medulloblastoma was performed. We evaluated serum IGF-1 and insulin-like growth factor binding protein-3 concentrations. Further, we examined growth status and changes with GH treatment according to treatment modality.
RESULTS: GH deficiency was observed in 28 patients (82 %). The initial height at the start of GH treatment was -2.35 ± -1.53 standard deviation score (SDS) and increased to -1.85 ± -1.28 SDS by 1 year, -1.64 ± -1.46 SDS by 2 years, and -1.42 ± -1.49 SDS by 3 years after GH treatment. The final height was -1.54 ± -1.06 SDS. Gender, surgical method, tumor location, tumor size, and type of radiation did not correlate with height gain. A younger age at the initiation of GH treatment correlated with height gain. The initial serum IGF-1 concentration was -1.73 ± -0.42 and increased significantly to -0.74 ± -0.21 SDS by 1 year after GH treatment. The serum IGF-1 SDS increment correlated significantly with height gain.
CONCLUSIONS: Beginning GH treatment at a younger age was an important prognostic factor for growth outcome. Serum IGF-1 increment correlated with height gain during GH treatment. Thus, early GH treatment and analysis of serum IGF-1 might be helpful for improving final height or growth outcome.