Long‐term effects of cranial irradiation on endocrine function in children with brain tumors a prospective study

This study prospectively evaluated the endocrine function of 11 children treated with cranial irradiation (CRT) for brain tumors. All tumors were remote from the hypothalamic‐pituitary axis. Children were studied before treatment and at 3, 6, and 12 months after the completion of CRT. T4, thyroid‐stimulating hormone, prolactin, plasma cortisol, and urinary follicle‐stimulating hormone and lueteinizing hormone values were normal before and after treatment in all patients. Growth hormone (GH) deficiency was identified in 0 of 7 patients before treatment, in 2 of 7 patients 3 months post‐CRT, in 9 of 11 patients 6 months post‐CRT, and in 7 of 8 patients 12 months post‐CRT. Growth deceleration was identified in five of seven prepubertal patients. GH deficiency is an extremely common sequelae of CRT, beginning as early as 3 months after the completion of CRT. The deficit is progressive over time.