[The endocrine effects of smoking]

Almost one third of men and women smoke in Belgium. Besides the well known tobacco's neck and cardiopulmonary systems adverse effects as well as associated neoplasms, today we recognize other deleterious consequences of tobacco on the neuroendocrine, thyroid and reproductive systems. Not only active smokers but also the fetus carried by a smoking mother is at risk for important health problems. Tobacco is a recognized risk factor of occurrence of ophtalmopathy. Some of the active components of tobacco as the thiocyanates are goitrogenic. Tobacco is a risk factor for men and women's infertility. Newborns from parents that smoke are at risk for sudden death. These consequences represent a major public health issue. A campaign for smoking cessation has been recently launched by the Federation of Public Health Service and the INAMI in Belgium.

[Traumatic brain injury and subarachnoid hemorrhage as a cause of hypopituitarism: a review]

Brain injuries namely traumatic brain injuries (TBI) and subarachnoid haemorrhage (SAH) are relevant causes of acquired adult hypopituitarism, perhaps more prevalent than ever believed. TBI represent a major health problem with an annual incidence of 300 cases per 100.000. SAH affects six new cases per 1.000.000 habitants in USA. In Belgium we estimate nearly 30.000 new TBI cases and 600 SAH cases per year. In the English literature, TBI secondary hypopituitarism has been well documented in 14 retrospective and prospective series accounting for 1.077 cases. In all these series the main pituitary deficits were: GH (14%), ACTH (14%), gonadotrope (18%), TSH (7%) and diabetes insipidus (4%). SAH was documented as a cause of hypopituitarism in three retrospective series accounting for 110 cases and in one prospective series. In all these series main pituitary deficits were GH (25%), ACTH (15%), gonadotrope (8.5%), TSH (6%) and diabetes insipidus (4%). In this review, we analyze recent data and discuss diagnostic and treatment features of secondary hypopituitarism due TBI and SAH.

[Paraneoplastic endocrine syndromes: diagnosis and management]

Paraneoplastic endocrine syndromes define a group of secondary signs and symptoms associated to a neoplasia, independently from the location of the primary tumor or its metastases. Paraneoplastic or ectopic endocrine syndromes usually result from aberrant hormone precursors or hormone-like substances by tumours. Knowledge of paraneoplastic endocrine complications is important both for the early diagnosis of neoplasia and the prognosis of the patient. In this review we discuss almost all reported paraneoplastic endocrine syndromes. We analyze their prevalence, etiology, laboratory diagnosis and treatment.

Familial pituitary adenomas

The majority of pituitary adenomas occur sporadically, however, about 5% of all cases occur in a familial setting, of which over half are due to multiple endocrine neoplasia type 1 (MEN-1) and Carney's complex (CNC). Since the late 1990s we have described non-MEN1/CNC familial pituitary tumours that include all tumour phenotypes, a condition named familial isolated pituitary adenomas (FIPA). The clinical characteristics of FIPA vary from those of sporadic pituitary adenomas, as patients with FIPA have a younger age at diagnosis and larger tumours. About 15% of FIPA patients have mutations in the aryl hydrocarbon receptor interacting protein gene (AIP), which indicates that FIPA may have a diverse genetic pathophysiology. This review describes the clinical features of familial pituitary adenomas like MEN1, the MEN 1-like syndrome MEN-4, CNC, FIPA, the tumour pathologies found in this setting and the genetic/molecular data that have been recently reported.

[Clinical and genetic characterization of FIPA (familial isolated pituitary adenomas)]

Pituitary adenomas are common brain tumours at autopsy and radiological series of unselected population. Historically, few epidemiologic data regarding the prevalence of clinically apparent pituitary adenomas have been available. Recently, a cross-sectional study conducted in Liège, Belgium, noted that clinically-apparent pituitary adenomas occurred with a prevalence of 1:1064 inhabitants, which is 3.5-5 times the previously reported prevalence. Pituitary adenomas occur predominantly as sporadic tumors, but also in a familial setting or associated to some familial/isolated tumoral syndromes. The recent characterization of the novel clinical entity FIPA (Familial Isolated Pituitary Adenomas) increased the prevalence of familial pituitary adenomas which account now for about 5% of pituitary tumors. Distinct genetic mechanisms are continuously identified and increase our understanding of the complex clinical presentation and sometimes unpredictable evolution of pituitary adenomas.

Update on the treatment of pituitary adenomas: familial and genetic considerations

Clinically-relevant pituitary adenomas occur with a prevalence of approximately 1 per 1000 population in Belgium. Pituitary adenomas that occur in families are likely to have an important genetic pathophysiological basis. Currently about 5% of all pituitary adenoma cases have a family history of pituitary adenomas, classically due to multiple endocrine neoplasia type 1 (MEN1) and Carney complex (CNC). Over the last decade we have described non-MEN1/CNC familial pituitary tumours that include all tumour phenotypes, a condition named 'familial isolated pituitary adenoma' (FIPA). Clinical features of FIPA differ from those of sporadic pituitary adenomas in that patients with FIPA are often younger and have larger tumours at diagnosis. Approximately 15% of FIPA patients have mutations in the aryl hydrocarbon receptor interacting protein gene (AIP), which indicates that FIPA may have a diverse genetic pathophysiology. In this review we examine new findings on the epidemiology of pituitary adenomas and we review familial causes of pituitary adenomas with a particular emphasis on modern clinical testing. In addition, the clinical and genetic features of FIPA are described as FIPA represents a useful framework to study the features of pituitary adenomas that occur in a familial setting.

Biometrology of physical properties of skin in thyroid dysfunction

OBJECTIVE

There is ample clinical evidence that skin is responsive to physiopathological levels of circulating thyroid hormones. The aim of the study was to assess some physical changes of the skin in the presence of moderate thyroid dysfunction.

SETTING

University Hospital.

PATIENTS AND METHODS

A total of 119 adults suffering from hypothyroidism or hyperthyroidism and 60 healthy controls were enrolled in this study. Hormonal dosages (TSH, fT3, fT4) were assessed in the serum. A series of biometrological assessments were also performed on the volar and dorsal aspects of the forearms. These included electrometric assessments (Nova Dermal Phase Meter, Corneometer), evaporimetry (Tewameter)), colorimetry (Mexameter), ultrasound shear wave propagation (Reviscometer) and squamometry X. Correlations were searched between each of the serum hormonal dosages and each of the biometrological parameters.

RESULTS

The hormonal changes in the untreated patients with thyroid dysfunction were modest in intensity. A few outlier values with regard to the normal range were found for each biometrological parameter. No correlations were found between fT3 or fT4 and each of the physical parameters. By contrast, significant negative linear correlations were found between thyroid-stimulating hormone (TSH) and skin hydration measured by the Corneometer and the Nova DPM.

CONCLUSION

This multipronged exploratory study shows that direct or indirect effects of TSH may influence the stratum corneum hydration. This correlation seemed very sensitive, as no other specific biophysical parameter was significantly correlated with the thyroid hormonal concentrations in the serum. However, our findings do not exclude the possibility of some other skin changes supervening in case of more severe thyroid dysfunction. The mechanism by which TSH alters the stratum corneum hydration is yet unknown.

[Hypogonadism due to LH deficiency]

A 30-year-old man was investigated for delayed puberty and infertility. These investigations showed a complete absence of circulating luteinizing hormone (LH). Genetic studies revealed a missense mutation in the LHbeta gene (G36D). This mutation disrupts a vital cystine knot motif and abrogates the heterodimerization and secretion of LH. Treatment with hCG was instituted, which led to arise in testosterone and improvement in spermatogenesis. After in vitro fertilization the patient had a son who was heterozygous for the G36D mutation. A second patient with similar clinical and biological presentation has been explored. A non-frame shift deletion of 3 base-pairs was discovered at position 20 which led to the deletion of a lysine residue. The proband and his prepubescent brother were homozygotic for this mutation. These cases illustrate the important physiological role of LH in male sexual maturation and fertility.

Clinical characterization of familial isolated pituitary adenomas

CONTEXT

Familial pituitary adenomas occur rarely in the absence of multiple endocrine neoplasia type 1 (MEN1) and Carney complex (CNC).

OBJECTIVE

Our objective was to characterize the clinical and genealogical features of non-MEN1/CNC familial isolated pituitary adenomas (FIPA).

DESIGN AND SETTING

We conducted a retrospective study of clinical and genealogical characteristics of FIPA cases and performed a comparison with a sporadic population at 22 university hospitals in Belgium, Italy, France, and The Netherlands.

RESULTS

Sixty-four FIPA families including 138 affected individuals were identified [55 prolactinomas, 47 somatotropinomas, 28 nonsecreting adenomas (NS), and eight ACTH-secreting tumors]. Cases were MEN1/PRKAR1A-mutation negative. First-degree relationships predominated (75.6%) among affected individuals. A single tumor phenotype occurred in 30 families (homogeneous), and heterogeneous phenotypes occurred in 34 families. FIPA cases were younger at diagnosis than sporadic cases (P = 0.015); tumors were diagnosed earlier in the first vs. the second generation of multigenerational families. Macroadenomas were more frequent in heterogeneous vs. homogeneous FIPA families (P = 0.036). Prolactinomas from heterogeneous families were larger and had more frequent suprasellar extension (P = 0.004) than sporadic cases. Somatotropinomas occurred as isolated familial somatotropinoma cases and within heterogeneous FIPA families; isolated familial somatotropinoma cases represented 18% of FIPA cases and were younger at diagnosis than patients with sporadic somatotropinomas. Familial NS cases were younger at diagnosis (P = 0.03) and had more frequently invasive tumors (P = 0.024) than sporadic cases.

CONCLUSIONS

Homogeneous and heterogeneous expression of prolactinomas, somatotropinomas, NS, and Cushing's disease can occur within families in the absence of MEN1/CNC. FIPA and sporadic cases have differing clinical characteristics. FIPA may represent a novel endocrine neoplasia classification that requires further genetic characterization.

[Tall stature: some classical syndromes]

We describe the findings of XYY syndrome in the setting of encountering an individual with this particular condition in the endocrinology clinic. XYY syndrome is a relatively frequent if unfamiliar condition, which is characterized by taller than average height. The extra Y chromosome may play a role in determining the height of these individuals. From this case, a differential diagnosis of tall stature is outlined, in addition to a description of the principal syndromes associated with gigantism. These primarily include Klinefelter syndrome, Marfan syndrome, androgen resistance and growth hormone excess. These various entities are described from the point of view of their symptomatology, biology, pathophysiology and therapeutic characteristics.

[Thyroid nodules]

Thyroid nodules are commonly encountered in clinical practice. They are present in 4 to 7% of the population by neck palpation and 30 to 50% by ultrasonography. Most are benign and could be neglected by the clinician and his patient. However, 5% of nodules are malignant, requiring surgical treatment; therefore, an exhaustive evaluation is needed. The diagnostic approach includes physical examination, laboratory analysis, ultrasonography, radioisotope imaging, and fine needle aspiration. This article, based on the literature and the authors'experience, provides recommandations for thyroid nodule management.

[How do you investigate an elevated calcitonin level?]

This article describes a case of lung cancer with associated hypercalcitoninemia in a man with a goitre. The case raises the problem of the differential diagnosis between medullary thyroid carcinoma and a neuroendocrine neoplasm with ectopic calcitonin secretion. The article first reviews the physiology of calcitonin, then outlines the diagnostic tests that are required to investigate hypercalcitoninemia and finally discusses the interpretation of test results.

[Cutaneous signs of endocrinopathies]

Some cutaneous lesions accompany or reveal endocrine disorders. Identifying the endocrinopathy is very important because it sometimes allows corrective rather than symptomatic treatment. The most frequenly involved diseases include thyrotoxicosis, hypothyroidism, the auto-immune disorders of thyroid, Cushing syndrome, Addison disease, acromegaly, androgen-dependent disorders, hypopituitarism, hypoparathyroidism, pseudohypoparathyroidism and diabetes mellitus.

Clinical and genetic features of familial pituitary adenomas

Inherited or familial pituitary tumor syndromes such as multiple endocrine neoplasia type 1 and Carney complex provide an important insight into the genetics and molecular pathology of endocrine cancers. Our understanding of these conditions is expanding rapidly due to the identification of the genes and proteins affected and the availability of murine knockout models. The successes achieved to date in understanding multiple endocrine neoplasia type 1 and Carney complex have helped in the identification and study of new inherited pituitary tumor syndromes such as isolated familial somatotropinomas. This review assesses the current status of research into the clinical features, genetics and molecular pathologies of multiple endocrine neoplasia type 1, Carney complex, and isolated familial somatotropinomas, and details ongoing work to delineate familial isolated pituitary adenomas, a potentially new clinical entity.

[Secondary forms of diabetes mellitus associated with endocrine diseases]

Diabetes mellitus may occur in association with endocrine disorders and is termed "other causes of diabetes" by the American Diabetes Association. Hyperglycaemia results from sustained excessive hormonal secretion, which alters insulin secretion or action. It is characterized by the absence of ketosis because of the persistence of endogenous insulin secretion. Diabetes is usually reversible with successful treatment of the underlying endocrine disorder and the correction of hormonal overproduction. Most important endocrine diseases associated with diabetes mellitus are briefly described and the underlying mechanisms of glucose abnormalities are discussed.

Octreotide (long-acting release formulation) treatment in patients with graves' orbitopathy: clinical results of a four-month, randomized, placebo-controlled, double-blind study

There are few effective, safe modalities for the management of Graves' ophthalmopathy (GO), a cell-mediated immune comorbidity of thyroid disease. Somatostatin analogs inhibit lymphocyte proliferation and activation, and accumulate in the orbital tissue of patients with GO. A double-blind, placebo-controlled study of a long-acting somatostatin analog [16 wk of long-acting release formulation of octreotide (octreotide-LAR)] was conducted in 51 patients with mild active GO with the aim of preventing deterioration and precluding the need for more aggressive therapeutic modalities, such as glucocorticoids or radiotherapy. No treatment effect was observed for the primary end point (a composite parameter defining the outcome as either success or failure on the basis of changes in class/grade of the severity index and Clinical Activity Scale of GO). The Clinical Activity Scale score was reduced for patients treated with octreotide-LAR, but without any significant difference with respect to patients receiving placebo. However, octreotide-LAR significantly reduced proptosis (as measured by exophthalmometry). This was associated with nonsignificant differences in favor of octreotide-LAR in a series of proptosis-related parameters: class III grade, opening of the upper eyelid, the difference in ocular pressure between primary position and upgaze, and extraocular muscle involvement. By magnetic resonance imaging evaluation the extraocular muscle volumes appeared reduced, but nonsignificantly. No significant correlation between the initial uptake of the somatostatin analog indium-labeled and the response to treatment was observed. One patient in the octreotide-LAR group developed gallstones. In this study, octreotide-LAR did not seem suitable to mitigate activity in mild GO. Surprisingly, it significantly reduced proptosis, one of the most debilitating symptoms of GO. Additional studies are warranted to define the benefit to risk ratio of the somatostatin analogs in this indication.

Tensegrity and type 1 dermal dendrocytes in acromegaly

BACKGROUND

Skin is enlarged and doughy in acromegaly. Alterations have been reported in the structure of the extracellular matrix (ECM) and in the mechanical properties of the dermis. It is recognized that internal tensions in the dermis give rise to active cell-ECM and cell-cell mechanical interactions. This mechanobiological aspect can lead to functional and conformational changes in the cells. Such alterations in connective tissue cells have not been explored so far in acromegaly. The aim of the study was to assess structural changes in the dermal ECM, and in the number and shape of factor XIIIa-positive type I dermal dendrocytes (DDs) in acromegaly.

MATERIALS AND METHOD

A total of 32 patients with acromegaly (three untreated, 17 with active disease under somatostatin analogues and 12 cured) were examined. Both the maximum and the most recent IGF-1 (insulin-like growth factor) dosages recorded in the patients' files were retrieved. Skin biopsies were taken from their forearms. Histochemistry, immunohistochemistry, morphometry and electron microscopy were used.

RESULTS

Collagen-bundle coarsening and acidic glycosaminoglycan deposits were found irrespective of the current endocrine status. Dermal dendrocytes were often markedly reduced in numbers, but those present were plump with few dendrites. A negative correlation was found between DD numbers and the maximum IGF-1 dosages recorded in the patients' files. A similar although weaker trend was found with the most recent IGF-1 dosages.

CONCLUSIONS

Collagen, glycosaminoglycans and DDs appeared affected in acromegaly, even when the hormonal status was controlled after surgery and/or somatostatin analogue treatment. The persisting conformational change of DDs suggests a modification in cellular tensegrity, perhaps initiated by hormonal effects and probably maintained by alterations in the ECM interactions.

An overview of the epidemiology and genetics of acromegaly

Historical data indicate that pituitary tumors represent 10% of intracranial tumors, while adenomas are noted in approximately 14-23% of normal subjects on autopsy or magnetic resonance imaging (MRI). About 2.5% of these tumors stain positive for GH in histopathologic studies. In contrast, the prevalence of clinically diagnosed acromegaly is lower at 36-69 per million population. Ongoing studies indicate that the actual prevalence of acromegaly in the community may be higher than previous epidemiologic data suggest. Acromegaly can occur both sporadically and in the setting of familial conditions, such as multiple endocrine neoplasia type 1 (MEN1) and Carney complex (CNC). Isolated familial somatotropinoma has been described and newer data suggest that acromegaly may also occur in non-MEN1/CNC families in combination with other pituitary tumor phenotypes.

Hormonal and biochemical normalization and tumor shrinkage induced by anti-parathyroid hormone immunotherapy in a patient with metastatic parathyroid carcinoma

Parathyroid carcinoma is a rare cause of primary hyperparathyroidism, and the efficacy of medical therapy and chemo- and radiotherapy is poor in recurrent or metastatic disease. We report the first case of PTH immunization in which tumor shrinkage accompanied hormonal, biochemical, and clinical improvements in a patient with metastatic parathyroid carcinoma.A 50-yr-old woman with refractory parathyroid carcinoma and pulmonary metastases was immunized eight times between February 2001 and December 2003 with bovine and modified human PTH fragments and intact human PTH, mixed with Freund's adjuvant. Total and ionized calcium and PTH levels were assayed weekly for 6 months and regularly thereafter. Thoracic computed tomography scans were performed regularly. Antibodies to all PTH fragments were detected after two immunizations. Baseline PTH and total calcium were 213.0 ng/liter and 13.96 mg/dl, respectively, and remained elevated during the first three immunizations. From the fourth immunization onward, PTH and calcium decreased, and the patient's clinical condition improved markedly. PTH and calcium levels have remained controlled for more than 24 months, and the sizes (surface area) of pulmonary metastases decreased from baseline by 39-71%. This is the first evidence that PTH immunization not only can improve clinical, hormonal, and biochemical measures in parathyroid carcinoma but also has an antitumor effect.

[Therapeutic strategies in somatotroph adenomas with extrasellar extension: role of the medical approach, a consensus study of the French Acromegaly Registry]

From the first 198 patient files included into the French Acromegaly Registry, we analyzed 68 patients harboring a somatotroph adenoma with extrasellar extension, after exclusion of those treated by stereotactic or conventional radiotherapy. In these patients (including 37 women), aged 21-77 yr. (45.7 +/- 13.3), GH concentrations ranged from 2-260 microg/L (38.6 +/- 44.3), and IGF I from 86-967% of age-matched upper limit of normal (303 +/- 164). Maximal diameter of the adenoma at MRI was 11-36.5 mm (20.4 +/- 6.5), with cavernous sinus involvement in 68% of cases. Three subgroups were defined: 20 patients treated by long-acting somatostatin analogs only (group M), for a mean duration of 3 yr. (extremes 1-7 yr.), 48 patients initially treated by transsphenoidal surgery (group C), of whom 21 were secondarily treated by long-acting somatostatin analogs (group CM) for a mean duration of 1.2 yr. (extremes 0.2-2 yr.). All 3 groups were not statistically different in terms of tumor mass and initial levels of GH and IGF-1. Patients from group M were significantly older than those of the other groups (p<0.05).

RESULTS

46% of patients from group C after surgery vs. 45% of patients from group M had a mean GH below 2.5 microg/L. Biochemical remission (GH<2.5 microg/L and normal IGF1 normal) was obtained in 31% of cases in group C, vs. 25% in group M. In this group, a decrease of the largest tumor diameter was observed in 10 patients (71.5%), ranging from 10-25% in 7 (50%) and exceeded 50% in 3 (21.5%). In group CM, the biochemical remission rate (42%) and final GH or IGF1 values were not significantly different from group M. In conclusion, these data suggest that surgery or long-acting somatostatin analogs have a comparable efficacy in terms of remission rates in somatotroph macroadenomas with extrasellar extensions.