We report the outcome of growth hormone (GH) therapy in 34 children (17 boys and 17 girls) with brain tumors in whom hypopituitarism developed. The types of tumors included the following: craniopharyngiomas (18); germinomas (four); astrocytomas (three); chromophobe adenomas (three); medulloblastomas (two); glioma (one); dermoid (one); retinoblastoma (one); and metastatic rhabdomyosarcoma from the pelvis (one). Ninety-four percent of the patients were GH deficient post-tumor therapy, which consisted of surgery with and without radiotherapy. Twenty-four of 34 patients received GH. Eight of 24 patients receiving GH had recurrence of tumor; 16 were tumor free eight to 72 months after initial therapy. Eleven patients had 12 recurrences. Patients with tumor recurrence had a considerably lower growth rate during the first year of GH therapy than those without recurrence (mean, 3.5 +/- 1.3 cm/yr v 6.2 +/- 2.5 cm/yr). Three of 11 patients with recurrence had not received GH therapy; however, one was receiving testosterone intramuscularly monthly at the time of a second recurrence. Thus, 24 of 34 patients with brain tumors and hypopituitarism received GH therapy. Eight (33%) of 24 had tumor recurrence, compared with three (30%) of ten who did not receive GH. The data suggest that GH therapy is probably not associated with increased rate of tumor recurrence.