EFFICACY OF GROWTH-HORMONE REPLACEMENT THERAPY IN CHILDREN WITH ORGANIC GROWTH-HORMONE DEFICIENCY AFTER CRANIAL IRRADIATION

We evaluated the growth response of 20 childhood cancer survivors who received growth hormone (GH) replacement therapy (0.3 mg/kg/week) for at least 12 months. In all subjects, GH deficiency was associated with cranial irradiation and was documented with growth charts, bone age, and somatomedin C levels; at least one GH stimulation test was availab le for 14 children. Pretreatment overall growth velocity was 3.3 +/- 0 .5 cm/year (mean +/- SE) over a 3-year period. After GH replacement, g rowth velocity was 8.6 +/- 0.6 cm/year during the first year (n = 20), 7.2 +/- 0.5 cm/year during the second year (n = 17), 5.9 +/- 0.6 cm/y ear during the third year (n = 11), and 6.1 +/- 0.6 cm/year during the fourth year (n = 7). Growth response, tabulated by age at onset of GH replacement, was compared with the response in GH-naive children with idiopathic GH deficiency (data obtained through the Genentech Inc. Na tional Cooperative Growth Study Summary, September 1991); the growth v elocity fell within the range described for idiopathic GH deficiency a djusted for either chronological or bone age. We conclude that childre n with GH deficiency after cranial irradiation for neoplastic diseases respond to GH replacement therapy as well as children with idiopathic GH deficiency.