Long-term consequences of growth hormone replacement and cranial radiation on pituitary function

Abstract

This thesis covers the consequences of cranial irradiation of non-pituitary tumors, eg nasopharyngeal carcinoma, on pituitary function. In chapter 2 we have performed a meta-analysis of available data reported in literature on pituitary function after cranial radiotherapy for head and neck and non-pituitary tumours. In this study, we found a 0,66 (CI 0,55-0,76) prevalence of hypopituitarism of any kind in a group of studies with a high level of heterogeneity. In chapter 3 the results of a cohort study are presented, we found that 62% of these had developed hypopituitarism during a variable period after cranial irradiation. Pituitary insufficiency of any form was present in 55% of cases within 5 years after radiotherapy, and amounted to 75% and 90% of patients after 10 and 15 years, respectively. Chapter 4-8 adress the consequences of long-term rGH replacement. rGH replacement can be safely initiated in adult patients with severe GHD and has to be monitored throughout the years, enabling to make individual adaptations based upon alteration in e.g. MS and bone mass for each patient every year. It has to be noted that the long-term effects on quality of life should be more carefully addressed in future research.