Radiation and Hypothalamic Pituitary Function

Abstract

Abstract. Deficiency of one or more anterior pituitary hormones may follow treatment with external radiation when the hypothalamic-pituitary axis falls within the fields of radiation. Hypopituitarism has been described in patients who received radiation therapy for nasopharyngeal carcinoma, tumors of the pituitary gland or nearby structures, and primary brain tumors, as well as in children who underwent prophylactic cranial irradiation for acute lymphoblastic leukemia or total body irradiation (TBI) for a variety of tumors and other diseases.There is strong evidence that the hypothalamus is the major site of radiation-induced damage and a growing belief that the pathological basis for the damage is direct neuronal injury rather than vascular-mediated.As radiation therapy and chemotherapy for patients with tumors of the brain and surrounding structure improve, follow-up evaluation will need to focus less on the possibility of tumor recurrence and more on the delayed effects of therapy, including the endocrine effects. Pituitary hormone deficiencies are common and may not develop for many years.