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F Raue

Publications and source records attributed to F Raue.

At least 127 records · Page 7Linked to original sources
PubMed1992

Early diagnosis of the multiple endocrine neoplasia type 2 syndrome: consensus statement. European Community Concerted Action: Medullary Thyroid Carcinoma.

The diagnosis of medullary thyroid carcinoma by biochemical and genetic testing is possible in families with multiple endocrine neoplasia type 2. At an early stage total thyroidectomy usually cures the patient. As the clinical penetrance of the autosomal dominant, transmitted, multiple endocrine neoplasia type 2 gene is not complete, family screening is indicated for every new patient who presents with apparently sporadic medullary thyroid carcinoma. Problems related to a screening programme and early diagnosis have led the members of the European Community Concerted Action: Medullary Thyroid Carcinoma group to formulate a consensus on biochemical and genetic screening. For biochemical screening, measurement of basal and pentagastrin and/or calcium stimulated serum levels of calcitonin by radioimmunoassay are essential starting at the age of three and continuing annually until 35 years of age. Furthermore, annual screening for pheochromocytoma by measuring the urinary excretion of catecholamines and for hyperparathyroidism by serum calcium determination is indicated. Genetic screening using linked markers can be done with a 95% accuracy in informative families when DNA is available from at least two family members proven to be affected. Biochemical screening can thus be reserved for gene carriers, while those at low risk can be reassured. Combined biochemical and genetic screening for multiple endocrine neoplasia type 2 is important and effective for the cure of medullary thyroid carcinoma.

Adrenal Gland Neoplasms↗
PubMed1992

Clinical features of multiple endocrine neoplasia type 1 and type 2.

The term 'Multiple Endocrine Neoplasia' (MEN) denotes a genetically determined syndrome characterized by the independent appearance of benign or malignant changes of several endocrine organs as well as occasional changes of neural, muscular and connective tissue. Three different forms have been identified: MEN 1 (Werner's syndrome) includes parathyroid hyperplasia in combination with pancreatic islet cell and pituitary tumours; MEN 2a (Sipple's syndrome) includes medullary thyroid carcinoma in association with phaeochromocytoma and parathyroid hyperplasia; MEN 2b includes medullary thyroid carcinoma, phaeochromocytoma and mucosal neuromas. MEN syndrome is transmitted as an autosomal dominant trait with a high degree of penetrance. The changes in the individual glands appear to be causally and temporally independent of each other. A spectrum of pathological changes exist in the affected glands which range from hyperplasia to adenoma to carcinoma. The pathological process is almost always multicentric, often resulting in bilateral disease of organs. The appearance of an endocrine tumour known to be associated with MEN should alert the physician to the possibility of a MEN syndrome. When the possibility of such a syndrome exists, screening and long-term observation should be initiated to diagnose a carcinoma in its earliest stage, or before the development of clinical manifestations of hormone excess.

Adenoma, Islet Cell↗
PubMed1992

Determination of serum calcitonin by immunometric two-site assays in normal subjects and patients with medullary thyroid carcinoma.

We evaluated the clinical usefulness of a commercial two-site immunoassay for calcitonin, which is based on two monoclonal antibodies against distinct epitopes of calcitonin. The potential lower detection limit of the assay was 2 ng/l. Inter-assay and intra-assay variation were both < 11%. No cross reaction with calcitonins from different species (salmon and eel calcitonin) was found. Of the various fragments of human calcitonin, only the 11-32 fragment could be detected. Basal calcitonin concentrations in normals (n = 69) ranged from < 2 ng/l to 50 ng/l. Basal calcitonin concentrations in 30% of the men (< 2-48 ng/l) and 51% of the women (< 2-10 ng/l) were undetectable. Stimulation of calcitonin with pentagastrin (0.5 microgram/kg body weight) in normal subjects was followed by an increase in calcitonin in all men (n = 17) and in 60% of the women (n = 12). The upper reference value for pentagastrin-stimulated calcitonin concentrations for all 29 normals was 78 ng/l (defined as the 95th percentile): 79 ng/l for men, and 50 ng/l for women. Using a different immunoradiometric two-site assay, a similar percentage of "positive" responses to pentagastrin in normals was obtained (20 out of 29). Four previously thyroidectomized patients with medullary thyroid carcinoma had normal basal, but pathological stimulated calcitonin values at follow-up. At reoperation, cervical lymph nodes with tumour tissue were removed. Postoperatively, the patients had basal and stimulated calcitonin concentrations within the limits of the established reference range. In conclusion, reference ranges for basal and pentagastrin-stimulated calcitonin concentrations have been established for an immunometric two-site assay.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Somatostatin inhibits the norepinephrine-activated calcium channels in rMTC 6-23 cells: possible involvement of a pertussis toxin-sensitive G-protein.

The mechanisms by which somatostatin inhibits hormone release are complex and involve, among other things, reduction of both intracellular cAMP and intracellular calcium. We studied the influence of the long-acting somatostatin analogue octreotide on norepinephrine (NE)-induced changes in intracellular calcium ([Ca2+]i) in fura-2 loaded single cells of a rat medullary carcinoma cell line, rMTC 6-23. Increases in the extracellular calcium concentration ([Ca2+]e) induced a sudden rise in [Ca2+]i which could be blocked by EGTA or the calcium channel blocker verapamil. NE evoked a similar increase in [Ca2+]i, which also could be blocked by the addition of EGTA or verapamil. Octreotide prevented or reversed the NE-induced increase in [Ca2+]i. Pretreatment of the cells with pertussis toxin abolished the inhibitory effect of octreotide. Thus we conclude that the NE-induced rise in [Ca2+]i is due to an influx of [Ca2+]e, most probably through voltage-dependent calcium channels. Octreotide inhibits the NE-stimulated rise in [Ca2+]i by a pertussis toxin-sensitive G-protein, most probably through a direct effect on NE-activated calcium channels.

Animals↗
PubMed1992

Long-term excess of endogenous calcitonin in patients with medullary thyroid carcinoma does not affect bone mineral density.

In a cross-sectional study of 39 patients with medullary thyroid carcinoma (MTC), we have investigated the effects of long-term calcitonin excess on bone mineral density. Bone mineral density was measured by dual X-ray absorptiometry at the lumbar spine between the second and fourth vertebra and by single photon absorptiometry at the distal forearm. The mean observation time of each patient between diagnosis of tumour and measurement of bone mineral density was 62.4 months (range 1-158 months). The mean calcitonin serum level was 14.4 micrograms/l at the time of measurement of bone mineral density. All patients were substituted with 150-200 micrograms L-thyroxine daily. At both sites, the mean bone mineral densities of all patients with MTC were not significantly different from controls. Patients with normal calcitonin levels (below 0.2 micrograms/l) after treatment had a normal bone mineral density of the spine but significantly (P less than 0.05) reduced bone mineral density values of the forearm. This was due to the decreased body surface areas of patients in this subgroup. Patients with multiple endocrine neoplasia type IIa had significantly higher bone mineral densities. Other bone-influencing factors, such as postoperative hypoparathyroidism, calcium intake, diarrhoea, menopause, tumour stage, previous anti-tumour treatment, or thyroxine substitution dose, did not affect bone mineral density. We thus conclude that long-term excess of endogenous calcitonin in patients with MTC has no positive effect on bone mineral density.

Absorptiometry, Photon↗
PubMed1992

The natural course of multiple endocrine neoplasia type IIb. A study of 18 cases.

BACKGROUND: Multiple endocrine neoplasia (MEN) type IIb is an autosomal dominantly inherited disorder associated with medullary thyroid cancer, pheochromocytoma, and a characteristic phenotype. The present study was performed to investigate the natural course of the syndrome and to describe its expression. METHODS: The medical records of 18 patients with MEN IIb, seven male and 11 female, were reviewed. RESULTS: The mean age at diagnosis of MEN IIb was 18 years (range, 8 to 41 years). All 18 patients had medullary thyroid cancer. In three patients, medullary thyroid cancer was diagnosed via screening. In two of these patients, the calcitonin value normalized after thyroidectomy. One patient died of metastases from medullary thyroid cancer at the age of 20 years (median duration of follow-up, 10 years). Eight of the 18 patients had pheochromocytomas. All of our patients had neuromas and bumpy lips, and all but one had a marfanoid habitus. A large proportion of the patients had intestinal abnormalities (75%), thickened corneal nerves (69%), skeletal abnormalities (87%), and delayed puberty (43%). CONCLUSIONS: The course of medullary thyroid cancer in MEN IIb is not always as aggressive as is generally thought. Periodic examination of relatives who are at risk may lead to early diagnosis and curative treatment. Intestinal abnormalities, skeletal abnormalities, and delayed puberty are commonly found in association with MEN IIb.

Adolescent↗
PubMed1992

Measurement of free cytosolic calcium in single cells: method and application.

Intracellular calcium [Ca2+]i acts as an important intracellular messenger system for secretion and synthesis, cell growth and differentiation. In order to demonstrate definitively that a change in [Ca2+]i is responsible for a physiological event, one has to measure [Ca2+]i directly within intact cells and correlate the time course of any [Ca2+]i changes with the biological response. Measurement of [Ca2+]i was done in a single cell preloaded with fluorescent Ca indicator fura2 using a fluorescent unit (lonoquant) consisting of an inverted microscope (Zeiss IM 35) equipped with a mercury lamp and a rotating filter wheel containing filters at wavelengths of 340 and 380 nm. Cells were alternately excited and emission signals of fura 2-loaded cells were collected by a photomultiplier and recorded on-line on a computer screen. As a model system, the rat C-cell carcinoma cell line rMTC 6-23 secreting calcitonin was used. An acute elevation of extracellular calcium resulted in an increase in [Ca2+]i within 5 sec and rapid release of preformed calcitonin. This tight linkage between extracellular calcium and [Ca2+]i is mediated via Ca influx through voltage-dependent Ca channels. These channels are modulated by intracellular cAMP, yielding a rhythmic oscillation of [Ca2+]i, as well as by extracellular somatostatin blocking the Ca channel and the increase of [Ca2+]i via a pertussis toxin sensitive Gi protein. The change in [Ca2+]i is associated with changes in calcitonin secretion, confirming the stimulus secretion coupling via voltage-dependent Ca channels in C-cells.

Animals↗
PubMed1992

Microsurgical lymph node dissection for metastatic asymptomatic C-cell carcinoma.

In persistent, clinically inapparent medullary thyroid carcinoma, microsurgical dissection of all lymph node compartments of the neck was performed. Between August 1988 and September 1991, 28 cases (mean age 43.3 years) were treated with 38 surgical interventions. Twenty patients had the sporadic form and eight patients the familial form. Unilateral neck dissection resulted in normalization of serum calcitonin (CT) levels even after pentagastrin stimulation in two patients whereas 16 patients exhibited abnormal CT stimulation tests. Eight of ten patients who had bilateral neck dissections had positive pentagastrin test results after surgery. The main postoperative complications included loss of local cutaneous sensation, generally temporary, and unilateral recurrent laryngeal nerve paralysis.

Adolescent↗
PubMed1992

Somatostatin acts via a pertussis toxin-sensitive mechanism on calcitonin secretion in C-cells.

The effect of the somatostatin analog octreotide on cAMP-mediated calcitonin (CT) secretion and cAMP accumulation in C-cells was investigated. Glucagon stimulated cAMP accumulation and CT secretion with a maximal effect at a concentration of 10(-6) M. The cAMP antagonist RpcAMPs blocked the glucagon-induced CT secretion down to control levels. Therefore, no other second messengers seem to be involved in glucagon-stimulated CT secretion. Octreotide in increasing doses (10(-9) to 10(-6) M) inhibited cAMP accumulation and CT secretion with a maximal effect at a concentration of 10(-7) (40% and 29% of control values, respectively). Pretreatment of the cells with 100 ng/mL pertussis toxin for 24 hours abolished the inhibitory effect of octreotide on cAMP accumulation and CT secretion (82% and 58% of control values, respectively). Similar results were obtained under the influence of the phosphodiesterase inhibitor IBMX. Therefore, we conclude that somatostatin modulates adenylate cyclase-coupled CT secretion in C-cells via a pertussis toxin-sensitive G-protein possibly in an autocrine/paracrine way.

Adenylate Cyclase Toxin↗
PubMed1992

[Current aspects of the pathology, diagnosis and therapy of C-cell carcinoma. A symposium held in Bonn, July 1991].

An essential element in the histological differentiation of medullary thyroid cancer (MTC) from other thyroid tumors is the use of immunohistochemical methods. The detection of calcitonin in the tumor cells is decisive. Factors which impair the prognosis of MTC are age (> 40 y), male sex, elevated DNA-content and mitotic activity of the tumor cells, immunoreactivity against dopa decarboxylase, histaminase and Leu-M1-antigen. Family screening is based mainly on calcitonin-stimulation tests (using pentagastrin or calcium) as a genetic marker for routine screening is not available yet. Scintigraphic methods using 99mTc-(V)-DMSA, 201Tl-chloride or 99mTc-anti-CEA antibodies become more important, especially in the detection of recurrent disease. Selective venous blood sampling is another sensitive method for localizing recurrent disease. Surgical treatment plays the dominant role in the management of MTC. Complete thyroidectomy in conjunction with systematic lymphadenectomy is now the primary treatment of choice.

Carcinoma↗
PubMed1992

PDN-21 (katacalcin) and chromogranin A: tumor markers for medullary thyroid carcinoma.

The malignant C-cell releases several markers of potential clinical significance into the circulation. To determine the usefulness of these markers for management of medullary thyroid carcinoma (MTC), it is necessary to compare the usefulness of these markers with calcitonin (CT), the classical tumor marker for MTC. Measurement of serum concentrations of the peptide PDN-21 (katacalcin), a carboxyterminal cleavage product of procalcitonin, showed a high correlation with serum CT levels (r = 0.99, P < 0.01, n = 65 patients with MTC). The presence of equimolar concentrations of CT and PDN-21 (CT/PDN-21 molar ratio = 0.95 +/- 0.33) indicates the peptide is cosecreted with CT. Stimulation of CT release by intravenous pentagastrin was associated with a parallel increase of PDN-21, providing further evidence of cosecretion of these two peptides. Finally, measurement of either PDN-21 or CT in selective venous catheterization specimens was useful for localization of MTC. Chromogranin A (CgA) levels were also measured in patients with MTC. Circulating levels were elevated in most patients with advanced disease. There was a moderate correlation between CgA and CT serum levels (r = 0.87, P < 0.01, n = 61 patients with MTC). Pentagastrin did not stimulate CgA, and the long half-life of CgA in the circulation did not make it possible to use this peptide for tumor localization by selective venous catheterization. We conclude that measurement of PDN-21 provides an independent assay system for diagnosis, localization, and postoperative management of MTC, whereas CgA measurement is not useful in early diagnosis of MTC and is of limited value for localization or management of progressive disease.

Biomarkers, Tumor↗
PubMed1991

[Papillary thyroid carcinoma in a median ectopic thyroid associated with intra-abdominal thyroid tissue].

A 17-year-old female underwent surgical removal of a painless submental lump presumed to be a median cervical cyst. Histology showed a papillary thyroid carcinoma with invasion of the surrounding connective tissue. A 99m-technetium scan, performed in preparation for a planned total thyroidectomy, demonstrated no thyroid tissue. On subsequent 123-iodine scanning there was an area of increased uptake about 3 cm above the larynx, but no normal thyroid tissue. Histological sections, obtained during further surgical exploration of the base of the tongue, showed scattered thyroid cell rests in the lingual muscles. Whole-body scanning, carried out in connection with administration of radioiodine for ablation of remaining thyroid tissue, disclosed an unexpected area of increased uptake in the epigastrium. Sonography and CT scans failed to demonstrate any corresponding morphological abnormality. Following a further dose of radioiodine 4 months later, no areas of increased uptake were noted.

Abdominal Neoplasms↗
PubMed1991

Effects of 17 beta-estradiol on calcitonin secretion and content in a human medullary thyroid carcinoma cell line.

The presence of a direct estrogen effect on calcitonin secretion is controversial. Because most of the data available were obtained from complex in vivo systems, we chose an in vitro approach to assess the problem. Using a human C cell carcinoma cell line (TT cells) with well-documented estrogen receptors, we investigated the effect of 17 beta-estradiol (E2) on basal and stimulated calcitonin secretion, on calcitonin content, and on total cellular protein. After short (30 and 180 minutes) and long-term (24 h to 6 days) incubation of the cells with different concentrations of E2 (from 0.01 to 100 nM) we observed no stimulatory but a transient dose-dependent inhibitory effect on CT secretion and content. The nadir of the effect on CT secretion appeared at 24 h, demonstrating a reduction to 80.5 +/- 7.8% of control at 1 nM and to 59.1 +/- 15% of control at 100 nM E2. After 72 h, the CT levels of the E2-exposed groups returned to control levels. The acute stimulation of the cells with TPA plus forskolin after preincubation with E2 up to 6 days showed no difference in the increment of CT release compared to the control groups. Additionally, E2 had a dose-dependent stimulatory effect on cell protein content. The data demonstrate the absence of a direct stimulatory effect of E2 on CT secretion, revealing a dose-dependent inhibitory effect on CT secretion and content.

Calcitonin↗
PubMed1991

Superior local tolerability of human versus salmon calcitonin preparations in young healthy volunteers.

Possible local and systemic adverse effects following administration of salmon (sCT) and human (hCT) calcitonin (CT) have been evaluated in a double-blind, within-subject, comparative trial in 30 young, healthy volunteers. Each subject received 0.25 and 0.5 mg hCT and 100 IU sCT s.c.. Adverse effects and hypocalcaemia were recorded 1, 3 and 6 h after each injection. Significantly fewer local adverse reactions were observed after hCT (20 or 33%) than after sCT (80%), possibly due to the different vehicles employed (mannitol solution and acetic acid). The most frequent systemic adverse effects were gastrointestinal (nausea, vomiting), which occurred in 80% after 1 h, independently of the CT--preparation used. Hypocalcaemic changes were generally small and lasted longer after sCT. It is concluded that the hCT preparations were better tolerated locally than sCT in young, healthy volunteers, and that there were no differences in the systemic side effects or hypocalcaemic activity.

Adult↗
PubMed1991

Papillary carcinoma in an ectopic thyroid.

Ectopic thyroid tissue can be seen anywhere from the foramen caecum to the lower neck. Most frequently it presents as a thyroglossal duct cyst associated with a normal thyroid gland. Less common is total ectopia, which can occur as a lingual thyroid or occasionally in non-lingual locations. Malignant transformation of such ectopic tissue is extremely uncommon. Only 21 cases of lingual thyroid carcinomas have been reported until 1971. We present, to our knowledge, the first case of a papillary carcinoma in a non-lingual ectopic thyroid in the absence of an orthotopic thyroid.

Adolescent↗
PubMed1990

[Epidemiology of hypercalcemia. Significance of the determination of intact parathyroid hormone for differential diagnosis].

Serum-calcium levels were determined in 9666 hospital inpatients during one year. Hypercalcaemia was present in 101 patients (51 women, 50 men, mean age 57 years). In 46 patients, hypercalcaemia was caused by malignancy. The second commonest cause was primary hyperparathyroidism (pHPT) in 35 cases. In the other 20 patients, hypercalcaemia was related to thiazid medication (8 patients), elevated 25-hydroxy-vitamin-D3-levels (six patients) or immobilisation (two patients). In four patients, no cause was found. Intact parathyroid hormone levels reliably distinguished patients with pHPT (values greater than 60 ng/l) from patients with hypercalcaemia of other causes (values less than 40 ng/l). Other laboratory tests were less useful. Serum-calcium levels greater than 2.9 mmol/l were found only in pHPT and hypercalcaemia of malignancy. In pHPT, the medical history frequently revealed nephrolithiasis (12 patients) and gastrointestinal ulcers (8 patients), whereas weight loss was far more common in hypercalcaemia of malignancy (28 patients).

Adult↗