Hypopituitarism After Radiotherapy for Extracranial Head and Neck Cancers in Pediatric PatientsBhandare, Niranjan, MS*; Kennedy, Laurence, MD†; Malyapa, Robert S., MD, PhD*; Morris, Christopher G., MS*; Mendenhall, William M., MD*American Journal of Clinical Oncology: December 2008 - Volume 31 - Issue 6 - p 567-572 doi: 10.1097/COC.0b013e318172dc9f Original Article: Pediatric Buy Abstract Author InformationAuthors Article MetricsMetrics Objectives: To investigate the incidence of postradiation therapy (postRT) hypopituitarism (hp-pit) in pediatric patients treated for extracranial head and neck tumors. Methods: We retrospectively reviewed 30 pediatric patients treated with RT for extracranial head and neck tumors between 1970 and 2000. RT doses to the hypothalamic-pituitary axis were estimated by re-evaluating the treatment plans. Results: Clinical hp-pit was observed in 16 (53.3%) patients; the median detection latency was 3.3 years and the median dose to the pituitary was 40.7 Gy. Univariate analysis of clinical hp-pit revealed that the total dose to the pituitary was significant (P = 0.034) as was the patient's age at the time of RT (P = 0.018) showing higher susceptibility and more damage in younger patients. Though fractionation (P = 0.018) and adjuvant chemotherapy (P = 0.016) were significant in univariate analysis, the total dose received by patients in these 2 groups was higher than the median dose for all patients. A limited multivariate analysis with 3 variables indicated that the total dose to the pituitary was significant, but chemoradiation and fractionation were not. The 5- and 10-year rates of freedom from clinical hp-pit were 42% and 37%, respectively. Conclusions: Clinical manifestations of late radiation toxicity to the hypothalamic–pituitary axis were observed among the pediatric patients with hormone deficiencies. The development of hp-pit depends on the total dose received by the hypothalamic-pituitary axis and the age of the patient. Dependence on chemoradiation and fractionation were inconclusive. Relatively long latency before clinical manifestations indicates that periodic testing after RT in pediatric patients is necessary for early detection and management of hormonal deficiencies. From the Departments of *Radiation Oncology and †Endocrinology, University of Florida College of Medicine, Gainesville, Florida. Reprints: William M. Mendenhall, MD, 2000 SW Archer Road, P.O. Box 100385, Gainesville, FL 32610-0385. E-mail: firstname.lastname@example.org. © 2008 Lippincott Williams & Wilkins, Inc.