|
|
Endocrine Dysfunction in Non-pituitary Intracranial Tumors« Back to Volume 23, Issue 1, March 2007 - Table of Contents It is well known that hypothalamic-pituitary dysfunction frequently follows pituitary neurosurgery (NS) and/or radiation therapy (RT). However, the frequency of hypothalamic-pituitary dysfunction after NS only--without RT for non-pituitary intracranial tumors--is unclear. Schneider and colleagues assessed the presence of endocrine alterations in patients treated for non-pituitary tumors. They studied 68 consecutive adult patients (28 female, 40 male, age 45.0 ± 1.8 years) with intracranial tumors who underwent NS only (n = 17) or in combination with RT and/or chemotherapy (CT) (n = 51). In 20.6% of the patients, peripheral endocrinopathy related to CT and/or RT was present. Hypopituitarism was found in 38.2% of the patients. Total pituitary hormone, multiple pituitary, and isolated pituitary hormone deficits were present in 16.2%, 5.8%, and 16.2% of patients, respectively. The most common pituitary deficits were, in decreasing order: LH/FSH 29.4%, GH 27.9%, ACTH 19.1%, TSH 17.7%, and diabetes insipidus 4.4%. Hyperprolactinemia was present in 13.2% of patients. The prevalence of hypopituitarism was higher in patients who underwent NS only and in those with tumors located closely to the sella turcica. Of interest, 33.3% of patients with tumors not directly neighboring the sella , who underwent NS only without RT , also showed hypopituitarism. Three of the patients had isolated pituitary hormone deficiency (2 had isolated GH deficiency and one had isolated LH/FSH deficiency). One patient had isolated primary hypogonadism. Hypopituitarism and/or peripheral endocrine deficiency occurred even after NS only, without RT, for intracranial tumors distant from the hypothalamic-pituitary region. Therefore, endocrine evaluation and follow-up of these patients should be performed on a regular basis. Editor’s CommentThis is a very interesting observational study that provides important information for physicians who care for cancer survivors who have been treated for brain tumors. The long-term complications and late effects of endocrine impairments and neuropsychological problems may become apparent many years after conclusion of treatment. Another recent study also showed that irradiation of adult intracranial tumors also puts patients at high risk of hypopituitarism, albeit less than the previously-mentioned patient groups.1 Many possible causes of hypothalamic-pi tuitary damage must be taken into account. The brain tumor itself might cause damage by mass effects or infiltration. Moreover, metastatic destruction of the hypothalamus or pituitary gland could play a role in some cases. Surgical interventions might disrupt the tumor site and surrounding brain tissue,as well as the pathway of access. The detrimental effects of cranial radiation are also well-recognized to impair hypothalamic-pituitary function. Chemotherapy may also play a role in hypothalamic-pituitary dysfunction. As could be expected, in the study of Schneider and colleagues, the prevalence of various degrees of hypopituitarism and/or peripheral endocrine deficiency was very high in patients who underwent surgery for tumors in close proximity to the hypothalamic-pituitary region. More than two-thirds of them were affected. However, more than a quarter of the patients with tumors not directly neighboring the hypothalamic-pituitary region also showed pituitary alterations. The authors observed that hypopituitarism and/or peripheral endocrine deficiency occurs even after NS only (without RT) for non-pituitary intracranial tumors. This is particularly important, as these patients with tumors not directly neighboring the hypothalamic-pituitary region treated with NS only (without RT) are not usually considered for endocrine evaluation. The signs and symptoms of hypopituitarism and/or periphera l endocrine deficiency are often nonspecific and can be masked by the sequelae of NS, RT, and CT. They are, therefore, likely to be overlooked if endocrine dysfunction is not actively sought. Gonadotropin deficiency, GH deficiency, and hyperprolactinemia are more common in these survivors, and the presence of signs and symptoms related to these hormone deficiencies should be assessed by further endocrine evaluation. These hypopituitary patients do not always complain and may show no signs and symptoms attributable to the endocrine deficits. Therefore, regular endocrine evaluation and follow-up should be performed throughout life, even in patients with non-hypothalamus-pituitary tumors who underwent NS only without RT. Yoshikazu Nishi, MD
Reference - (linked to
|
Volume 25 Number 1
June 2009
www.GGHjournal.com
ISSN 1932-9032
)