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PubMed1991

[Late effects on the hypothalamo-pituitary function after the treatment of parasellar tumors].

Long term follow-up of patients submitted to treatment of parasellar tumours region is important for the detection of late therapeutic complications. In this study the authors conducted an evaluation of six patients with craniopharyngioma, one with germinoma, one with meningioma, and one epidermoid cyst. All above tumours were localized at parasellar region. Six out of nine patients had been treated both by surgery and by radiotherapy and the other three surgically only, on an average 3.8 +/- 3.2 years before this observation was carried out. Five patients were female with their ages average 24.3 +/- 18.8 years old. Evaluation consisted: in the first place, an intravenous infusion of thyrotropin-releasing hormone (TRH, 200 micrograms), gonadotropin-releasing hormone (GnRH, 100 micrograms), and insulin tolerance test (0.1 IU/Kg, regular insulin); and secondly, in measurements of pituitary hormones secretion at different time points--0, 20, 40, 60 and 80 minutes. We found both diminished response of growth hormone and cortisol in all the patients. Seven out of nine patients did not have adequate response to follicle-stimulating hormone. Three out of nine responded unsatisfactory to luteinizing hormone. Four out of nine showed inadequate responses to prolactin as well as, two out of eight to thyrotropin. We concluded that: (a) growth hormone and cortisol deficiency are the most frequent finding in these patients; (b) post-radiotherapy lesions can be located in the hypothalamus or pituitary, or even in both; (c) hypophysial and hypothalamic cells sensitivity to irradiation is different, according to their respective hormones; and (d) it is necessary a frequent endocrinologic follow-up of patients to detect late hormonal deficiencies.

Adolescent↗

PubMed1992

Stereotactic radiosurgery for pineal region tumors.

Our present treatment strategy for treating pineal region tumors is shown in Figure 5. We believe that stereotactic biopsy should be the first procedure in pineal region tumors so that a histologic diagnosis can be obtained. Based on the biopsy findings, the appropriate subsequent therapy, whether microsurgery, fractionated irradiation, or stereotactic radiosurgery, can be administered. Although our experience currently is limited to nine patients, we have found that stereotactic radiosurgery is a valuable alternative to microsurgery in the treatment of selected pineal region tumors.

Adolescent↗

PubMed1976

Prolactin-secreting pituitary tumor in early adolescence: hormonal and electron microscopical studies.

A 13-year-old boy was evaluated for an enlarged sella. There were no consistent visual field defects, and carotid arteriograms and pneumoencephalograms showed no extrasellar abnormality. The endocrine workup demonstrated a subnormal growth hormone reserve. The only other, but most striking abnormality, was an excessively high serum prolactin level, which was partially suppressed with levodopa. A chromophobe pituitary tumor was removed that had histological features suggestive of malignant neoplasm. Characteristics of a prolactin-secreting tumor were confirmed by electron microscopy. The serum prolactin levels decreased substantially after surgery and further after a course of pituitary irradiation; however, they continue to be elevated above normal. Prolactin determinations play in integral part in the evaluation for a possible pituitary tumor-not only for diagnostic purposes, but also to provide a parameter of future tumor activity in an established case. Electron microscopical studies are helpful in identifying the tumor as source of the excessive prolactin secretion.

Adenoma, Chromophobe↗

PubMed2001

Long-term Karnofsky performance status and neurological outcome in patients with neurohypophyseal germinomas.

Long-term posttreatment Karnofsky Performance Status (KPS) and neurological status of 16 patients with neurohypophyseal (NH) germinomas were retrospectively analysed, in order to deduce the best treatment modality to achieve a good outcome. The average age at treatment was 15.5 years (rouge 6-26) and they were followed up for 107.3 months (26-209). The KPS averaged 81.5 (0-100). Three patients were below 60 in the KPS. The first one had hemiparesis due to a delayed cerebrovascular accident (CVA), and the second became indifferent and inactive with recent memory loss. The third died from marginal recurrence of tumour and subsequent systemic metastasis. The low scores were all more or less attributable to complications related to irradiation: delayed CVA, diffuse cortical atrophy and inappropriate selection of irradiation field, respectively. The second case had the tumour origin at the hypothalamus, which indicates intraparenchymal tumour location as another factor to worsen the quality of life (QOL). Visual field and acuity, and EOM impairment were observed in eight and five patients, respectively. It improved in all patients but one. The visual and EOM dysfunction recovered satisfactorily and was not a disabling factor. The intraparenchymal lesion resulting in hemiparesis and higher cortical dysfunction due to either irradiation-related complications or tumour invasion is a major determining factor of lower KPS. Irradiation related complications are considered to be avoidable by reducing radiation dosage with appropriate chemotherapy and/or proper selection of irradiation field. Patients with smaller tumour size of less than 20 mm had higher KPS. Accordingly, repeated studies of tumour markers and neuroimages are required in patients with idiopathic diabetes insipidis, in order to detect the tumour, if present, at the small-sized and early stage.

Adolescent↗

PubMed1978

Endocrine dysfunction in the diencephalic syndrome of emaciation in infancy.

A 10-month-old boy with the clinical features of the diencephalic syndrome of emaciation due to a suprasellar spongioblastoma is described. The patient showed high basal levels of growth hormone (GH greater than 80 muU/ml on several occasions). In addition, elevated concentration of plasma testosterone (125.5 ng/100ml) was combined with a relatively high LH-increase to LHRH (45.6 mU/ml). After completion of irradiation basal GH-levels had been normalized, and GH responses to insulin induced hypoglycemia (IIH) and propranolol-glucagon (PG) were adequate. Complete clinical remission of emaciation occurred soon after radiation therapy and went parallel with the normalization of GH-regulation.

Astrocytoma↗

PubMed1996

Proopiomelanocortin, its derived peptides, and the skin.

Proopiomelanocortin (POMC) is a protein synthesized predominately in the pituitary gland but also in a variety of other tissues, including the skin. Through enzyme-mediated cleavage that varies among cell types, POMC can give rise to at least eight distinct peptides whose biologic roles are incompletely delineated. Although blood-borne pituitary-derived bioactivity for the skin was first recognized 80 years ago and the responsible neuropeptides isolated 20-40 years ago, our understanding of POMC-derived peptides in skin is still rapidly evolving. In particular, recent work in cultured human and murine skin-derived cells has demonstrated POMC gene expression as well as modulation of POMC and many of its derived peptides in response to physiologic signals including ultraviolet irradiation and cytokines. Immunoreactivity for these peptides has also been detected in normal skin and hair follicles, strongly suggesting cutaneous synthesis in vivo. Candidate autocrine or paracrine functions include enhanced melanogenesis, immunomodulation, and effects on cell cycle regulation and differentiated function in both the epidermis and its appendages. This article reviews recent data concerning POMC gene expression and regulation, protein processing, signal transduction, and biologic functions relevant to cutaneous biology.

Gene Expression↗

PubMedDate not supplied

[Effect of discontinuous short-wave electromagnetic field irradiation on the state of the endocrine glands].

A study was made of the effect of interrupted EMF SW of 500 and 250 V/m on endocrine glands of male rats. The following changes were noted: activation of neurosecretion in hypothalamus, inhibition of adrenocorticotropic and gonadotropic functions of hypophysis and adrenal cortex, degenerative and dystrophic changes in testes. The observed disorders were aggravated as the intensity of the field and duration of exposure increased.

Animals↗

PubMed2002

Inhibition of recovery of spermatogenesis in irradiated rats by different androgens.

We previously showed that exogenous testosterone (T) inhibited GnRH-antagonist-stimulated spermatogenic recovery in irradiated rats through an androgen-receptor-mediated action. In the present study, we tested whether the inhibition is attributable to T, a specific androgenic metabolite of T, or a general property of androgens in this system. In addition, we also tested whether estradiol-17beta (E2), a metabolite of T, is similarly inhibitory. Rats irradiated with 5 Gy were treated with a GnRH antagonist during wk 3-7. Neither irradiation nor GnRH-antagonist treatment produced biologically significant changes in the relative intratesticular levels of several androgenic metabolites. Next, groups of rats, irradiated and treated with GnRH antagonist as above, were given various doses of one of the following androgens: T, 5alpha-dihydrotestosterone, 7alpha-methyl-19-nortestosterone, methyltrienolone, or E2. The percentage of tubules showing differentiation (tubule differentiation index) was increased to 68% by the GnRH antagonist, from a value of 0.1% in irradiated-only rats at 13 wk after irradiation. All of the added androgens inhibited spermatogenic recovery, lowering the tubule differentiation index to between 0.4-36%, but no inhibition was observed with the addition of E2. Of all the androgen treatments tested, T (given as daily injections of T propionate) minimally inhibited spermatogenic recovery while maintaining androgen-responsive tissue weights, and might be most useful in clinical studies. Hormonal measurements in androgen-treated rats were most consistent with the androgen inhibition of spermatogenic recovery in irradiated rats being a combined result of a direct inhibitory effect of all androgens on the testis and an indirect effect through the pituitary by raising levels of FSH, which seems to add to the inhibition of spermatogenic recovery.

Androgens↗

PubMedDate not supplied

[The use of nuclear magnetic resonance in the diagnosis of hypophyseal adenomas (preliminary report)].

The paper is concerned with the use of a new tomographic method based on the principle of nuclear magnetic resonance (NMR-tomography) in the diagnosis of adenohypophyseal diseases. A NMR-tomograph with a resistive magnet (0.234 T) was employed. Altogether 15 patients with the most common types of hypothalamo-hypophyseal diseases including Itsenko-Cushing disease (6) of various degrees of severity, hyperprolactinemic hypogonadism (8), and one patient with acromegaly were investigated. NMR-tomography was shown to possess a high informative value permitting assessment of the presence of adenohypophyseal pathology without irradiation of a patient. NMR-tomography combined with routine methods of examination of patients with hypothalamohypophyseal pathology (roentgenography, computerized tomography, hormonal investigation) made it possible to improve considerably early diagnosis of pituitary adenomas and to specify the volume and type of tumor growth.

Acromegaly↗

PubMed1987

A case of Klinefelter's syndrome associated with hypothalamic-pituitary dysfunction caused by an intracranial germ cell tumor.

A 17 year-old boy was admitted to the hospital because of thirst, polyuria (5-61/day), delayed sexual development and muscle weakness. He appeared obese, had an eunuchoidal body habitus and was excessively tall. Chromosomal analysis revealed a 47XXY karyotype. Serum cortisol was 1.3 microgram/dl, LH, 10.4 mIU/ml, FSH, 2.0 mIU/ml, and testosterone, 10 ng/dl. Endocrinological dynamic tests indicated diabetes insipidus and hypopituitarism of a hypothalamic type. Brain CT disclosed the existence of a tumor shadow around the calcified pineal body, extending towards the suprasellar region. Replacement therapy with glucocorticoid and DDAVP was started. The patient complained of a headache and plasma AFP and hCG concentrations were 868 ng/ml and 68.6 IU/ml respectively. A hCG- and AFP- producing germ cell tumor was suspected and radiation therapy with 60Co was performed. Plasma AFP and hCG were decreased with significant clinical improvement. Soon after irradiation, he started to complain of a headache and had elevated AFP and hCG levels. Right hemiparesis and unconsciousness suddenly appeared and he died of left thalamic bleeding. This is the first case of Klinefelter's syndrome associated with intracranial germ cell tumor. Plasma testosterone levels fluctuated in parallel with the change in plasma hCG levels. This shows that the Leydig cells in this patient could respond to some extent to tumor-producing hCG.

Adolescent↗

PubMed1995

Anterior pituitary function in patients with nonfunctioning pituitary adenoma: results of longitudinal follow-up.

Studies of anterior pituitary function in patients treated for nonfunctioning pituitary adenomas have been limited by their short duration. The purpose of the present study was to examine pituitary function longitudinally among three types of patients: those with complete tumor removal (group A); those with subtotal or partial adenomectomy (group B); and those in group B who underwent additional radiation therapy (group C). The subjects were 33 patients whose anterior pituitary function was evaluated by provocative tests such as insulin induced hypoglycemia, thyrotropin releasing hormone administration test and luteinizing hormone releasing hormone administration test. They underwent preoperative evaluation and postoperative reevaluations at 2 weeks, 3 months, 6 months and annually thereafter, for over 10 years. Anterior pituitary function was restored within a year after surgery, if at all. No additional function was restored after one year from treatment. In group A, no one developed impairment of anterior pituitary function after one year from surgery. In group B, however, new impairment was noted at intervals, due to tumor regrowth. In Group C, deficiencies developed after one year, irrespective of tumor regrowth. In conclusion, lifelong endocrinological follow-up is recommended for patients receiving postoperative irradiation, and for patients with potential for tumor regrowth. On the other hand, patients with total adenomectomy may be exempted from periodic endocrinological follow-up if they do not need postoperative hormonal replacement therapy.

Adenoma↗

PubMed2001

Autoimmune hypothyroidism coexisting with a pituitary adenoma secreting thyroid-stimulating hormone, prolactin and alpha-subunit.

A 44-year-old woman presented to her GP with excessive tiredness. She had positive thyroid microsomal and thyroglobulin autoantibodies and was found to have an elevated serum thyroid-stimulating hormone (TSH) concentration of 8.37 (normal = 0.15-3.5)mU/L and a low normal total thyroxine (T4) of 86 (reference range 60-145)nmol/L. She was rendered symptom free on a dose of 150 microg of thyroxine per day. However, her TSH failed to return to normal, and following a further increase in her thyroxine dose she was referred to the endocrine clinic for further assessment. Her TSH at this stage was 14mU/L, free T4 (fT4) 28 (normal = 10-27)pmol/L and free T3 (fF3) 10 (normal = 4.3-7.6)pmol/L. She denied any problems with adherence to her medication. Her serum prolactin was elevated at 861 (normal = 60-390)mU/L. A pituitary tumour was suspected and an MRI scan showed a macroadenoma of the right lobe of the pituitary, extending into the suprasellar cistern. The tumour was resected trans-sphenoidally. Electron microscopy showed a dual population of neoplastic cells compatible with a thyrotroph cell and prolactin-secreting adenoma. Immunocytochemistry and cell culture studies confirmed the secretion of TSH, prolactin and alpha-subunit. Postoperative combined anterior pituitary function tests did not demonstrate any deficiency of anterior pituitary hormones. A repeat MRI scan showed no significant residual tumour; however, her serum TSH and prolactin levels remained high and she was given a course of pituitary irradiation. This case illustrates the difficulty of diagnosing a TSHoma when it coexists with autoimmune hypothyroidism. We believe the combination of pathologies reported here is unique.

Adrenocorticotropic Hormone↗

PubMedDate not supplied

Male reproductive system in patients exposed to ionizing irradiation in the Chernobyl accident.

Twelve men with different forms and stages of chronic radiation dermatitis caused by accidental exposure to beta and gamma irradiation during and after the Chernobyl atomic power plant accident were examined. Two patients had impotentia coeundi, and the others reported various impairments of sexual function. One patient had aspermia, two patients had azoospermia, one had oligospermia, and four had normal sperm counts. In three samples abnormal forms of spermatozoa were increased. Sperm motility was decreased in 3 samples and was normal in another. Hormonal analyses demonstrated low testosterone plasma levels in two patients, an increase of follicle stimulating hormone (FSH) levels in six patients, and a decrease of luteinizing hormone (LH) in one patient. In one patient who showed an increase of plasma prolactin level, associated with low testosterone and LH, a microadenoma of the pituitary gland (prolactinoma) was detected. It would appear that there is an association between accidental exposure to ionizing radiation of varying severity and the impairment of exocrine and endocrine testicular function, sometimes resulting in long-lasting physiological and psychological problems.

Accidents↗

PubMed1978

Rat differences in mammary tumor induction with estrogen and neutron radiation.

Young adult female rats of either the Sprague-Dawley stock or the ACI strain were each given an implant of a compressed pellet of 5 mg diethylstilbestrol (DES) and 15 mg cholestrol 2 days before irradiation with 0.4, 1.3, or 4.0 rads of 0.43-MeV neutrons. These rats were studied, along with appropriate irradiated and nonirradiated controls, until death or for a maximum of 48 weeks. Response differences between the strain and stock included the following: DES produced both pituitary tumors and mammary adenocarcinomas (MAC) in ACI rats only. Neutron radiation increased mammary fibroadenoma (MFA) formation in Srague-Dawley rats only. No interactions between DES and radiation on MAC formation in Sprague-Dawley rats or MFA formation in ACI rats were demonstrated. However, when DES and neutron radiation were combined, DES appeared to inhibit the MFA response to radiation in Sprague-Dawley rats. In contrast, DES appeared to act synergistically with neutron radiation on MAC formation in ACI rats. These results clearly demonstrate rat differences in mammary gland carcinogenesis in response to estrogen, to radiation, or to a combination of both agents.

Adenocarcinoma↗

PubMed1980

The microscopical structure and quantitative changes of pituitary cell populations in frogs (Rana esculenta L.) irradiated by ultraviolet light.

The percentage of cell populations of hypophysis pars distalis, their ultrastructure, degranulation phenomena and volume of cell nuclei easured by karyometry was examined in frogs, Rana esculenta L. irradiated by UV light. The observed changes, reflecting alterations of the secretory activity were most prominent in B2 cells producing gonadotropic hormones and in B3 cells probably responsible for the secretion of ACTH. A concomitant increase of the number of chromophobic cells was observed. The obtained results are discussed in relation to data from the existing literature.

Adrenocorticotropic Hormone↗

PubMed2002

Late health effects of childhood nasopharyngeal radium irradiation: nonmelanoma skin cancers, benign tumors, and hormonal disorders.

Nasopharyngeal radium irradiation (NRI) was widely used from 1940 through 1970 to treat otitis serosa in children and barotrauma in airmen and submariners. We assessed whether NRI-exposed individuals were at higher risk for benign tumors, nonmelanoma skin cancer, thyroid disorders, and conditions related to regulatory control of anterior pituitary hormones, such as growth and reproductive characteristics. We conducted a retrospective cohort study in 3,440 NRI-exposed and 3,088 nonexposed subjects, who as children were treated at nine ear, nose and throat clinics in The Netherlands between 1945 and 1981. Based on information from original medical records, we traced vital status through follow-up at municipal population registries. Disease status (including medical confirmation) and indicators of pituitary gland radiation damage were assessed from a self-administered questionnaire in 1997. The average radiation doses were 11, 7, and 1.5 cGy for pituitary, parotid, and thyroid gland, respectively, and 3.2 cGy for the facial skin. Among exposed subjects, 23 benign head and neck tumors were observed, compared with 21 among nonexposed subjects. Elevated risk of basal cell carcinoma of the head and neck area was observed in exposed subjects (odds ratio = 2.6; 95% confidence interval: 1.0-6.7). Exposed and nonexposed groups did not differ substantially with regard to thyroid disorders, height, and reproductive characteristics, although exposed males more frequently reported a history of fertility problems compared with nonexposed males (odds ratio = 1.4; 95% confidence interval: 1.0-2.1). We found no evidence of highly elevated risk of benign head and neck tumors, nonmelanoma skin cancer, thyroid disorders, or indicators of pituitary radiation damage after childhood NRI in The Netherlands.

Adolescent↗

PubMed1997

[Late effects of radiotherapy on the neuroendocrine system].

When the hypothalamic-pituitary axis (HPA) is included in the treatment field in children and adults, a variety of neuroendocrine disturbances are more common than has been appreciated in the past. Clinical damage to the pituitary and thyroid glands usually occurs months to years after treatment, and is preceded by a long subclinical phase. Primary brain tumors represent the largest group of malignant solid tumors in children. The survival rates of 50% reported in the literature are achieved at the expense of late occurring effects. Radiation-induced abnormalities are generally dose-dependent. Growth hormone deficiency and premature sexual development can occur at doses as low as 18 Gy in conventional fractionation, and is the most common neuroendocrine problem in children. In patients treated with > 40 Gy on the HPA, deficiency of gonadotropins, thyroid stimulating hormone, and adrenocorticotropin can be found. Following high-dose radiotherapy (> 50 Gy), hyperprolactinemia can be seen, especially among young women. Most neuroendocrine disturbances that develop as a result of HPA can be treated efficiently, provided that an early detection of these endocrine dysfunctions abnormalities is done.

Adult↗

PubMed1989

[Endocrine complications caused by cranial irradiation].

Cranial irradiation has become one of the leading causes of growth hormone (GH) deficiency. The risk and time of onset of GH deficiency depend mainly on the dose delivered to the hypothalamo-pituitary region: GH deficiency is infrequent after doses under 20 grays and nearly constant after doses above 45 grays. For a given dose, a younger age at the time of irradiation and administration of the dose over a shorter time period increase the risk of GH deficiency. GH secretion can be adequately evaluated using rapid stimulation tests and is usually well correlated with growth, except in patients with radiation-induced precocious puberty or growth delay due to radiation-induced cartilage lesions.

Adolescent↗