Growth hormone replacement therapy in children with medulloblastoma: Use and effect on tumor control

Purpose: Progress has been made in the treatment of medulloblastoma, the mo st common childhood malignant brain tumor: However, many long-term survivor s will have posttherapy growth hormone insufficiency with resultant linear growth retardation. Growth hormone replacement therapy (GHRT) may significa ntly improve growth, but there is often reluctance to initiate GHRT because of concerns of an increased likelihood of tumor relapse. Patients and Methods: This study retrospectively reviewed the use of GHRT f or survivors of medulloblastoma in 11 neuro-oncology centers in North Ameri ca who received initial treatment for disease between 1980 and 1993 to dete rmine its impact on disease control. A Landmark analysis was used to evalua te the relative risk of relapse in surviving patients. Results: Five hundred forty-five consecutive patients less than 15 years of age at diagnosis were identified. Six-year progression-free survival (mean +/- SD) was 40% +/- 5% in children less than 3 years of age at diagnosis c ompared with 59% +/- 3% for older patients. Older patients with total or ne ar-total resections (P =.003) and localized disease at diagnosis (P <.0001) had the highest likelihood of survival. One hundred seventy patients (33% +/- 3% of the cohort) received GHRT. GHRT use varied widely among instituti ons, ranging from 5% to 73%. GHRT was begun a mean of 3.9 years after diagn osis, later in children younger than 3 years at diagnosis (5.4 years). By L andmark analyses, for those surviving 2, 3, and 5 years after diagnosis, th ere was no evidence that GHRT increased the rate of disease relapse. Conclusion: This large retrospective review demonstrates that GHRT is under utilized in survivors of medulloblastoma and is used relatively late in the course of the illness. GHRT is not associated with an increased likelihood of disease relapse. J Clin Oncol 19:480-487. (C) 2001 by American Society of Clinical Oncology.