Pituitary and Hypothalamic Tumor Syndromes in Childhood

Excerpt

Central nervous system (CNS) tumors are the second commonest childhood malignancy, with 10% of these affecting the suprasellar and/or intrasellar regions. Survival has increased significantly over the last decade as a result of improved multimodality cancer therapies and better supportive care. Measurements of serum prolactin, α-fetoprotein, and β-hCG as well as baseline pituitary function tests are essential at diagnosis prior to commencement of any therapy. Craniopharyngiomas and low-grade gliomas account for most of these tumors, whilst other histological subtypes such as pituitary adenomas, germinomas, and hamartomas are rare. Non-neoplastic masses include pituitary hyperplasia and Rathke’s cleft cysts. Neurological syndromes and endocrine dysfunction are often present at diagnosis, and may be missed if not sought for. Post-diagnosis, endocrinopathies can evolve over decades secondary to tumor and/or treatment, necessitating long-term follow-up of such patients. Treatment of endocrine dysfunction is crucial not just to avoid the fatal consequences of untreated secondary adrenal insufficiency and/or diabetes insipidus, but also to improve quality of survival, and should be closely supervised by a pediatric endocrinologist with experience in the management of such patients. Growth hormone therapy in replacement doses in particular has not been shown to increase the risk of tumor recurrence. The “hypothalamic syndrome”, including variable hypothalamic dysfunction (e.g., sleep-wake cycle disturbances, temperature dysregulation, adipsia, and behavioral disorders) and hypothalamic obesity, is a common and as yet untreatable sequela of both tumor and treatment. The latter is caused by dysregulation of a network anorexigenic and orexigenic hormone signals which is only beginning to be elucidated. For complete coverage of all related areas of Endocrinology, please visit our on-line FREE web-text, WWW.ENDOTEXT.ORG.