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PubMed1999

Predictive DNA testing for multiple endocrine neoplasia 2: a therapeutic challenge of prophylactic thyroidectomy in very young children.

BACKGROUND: Patients with multiple endocrine neoplasia (MEN) type 2 are at risk for early medullary thyroid carcinoma (MTC). Recently, the cloning of the ret oncogene has made it possible to identify patients at risk for MEN 2 syndrome with a high degree of reliability before presenting any symptoms. METHODS: Children of families with MEN 2 were screened genetically if one of the parents was a known gene carrier of the RET proto-oncogene. If they were carriers, thyroidectomy was performed. RESULTS: The authors report five children with MEN 2 who underwent prophylactic thyroidectomy irrespective of the results of calcitonin screening tests after genetic screening had shown that they were carrier of the RET proto-oncogene. Apart from a temporary hypocalcemia in one, the operations were uneventful. Pathology results showed MTC in three children of one family with MEN 2A at age 2, 3, and 6 years. In two families with MEN 2B the thyroidectomy specimen showed bilateral MTC in a 1-year-old and a 3-year-old child. CONCLUSIONS: These findings show that MTC occurs at very young age in children with MEN 2. The authors advocate performing prophylactic thyroidectomy in the first year of life in children with MEN 2B and at age 2 years in children with MEN 2A to obtain an optimal cure rate.

Carcinoma, Medullary↗
PubMed1999

Familial medullary thyroid carcinoma: presymptomatic diagnosis and management in children.

Two kindreds with familial medullary thyroid carcinoma (MTC) are described in which affected family members had variable clinical and pathologic manifestations. Genetic testing in 2 children from one kindred revealed a mutation in exon 10, codon 618 (TGC to AGC) in the extracellular cysteine-rich region of the RET gene. In this kindred an 11-year-old had microscopic evidence of MTC; however, a 17-year-old had no evidence of pathology on thyroidectomy. In a second kindred a rare mutation in exon 14, codon 804 (GTG to TTG) of the intracellular tyrosine kinase region of the RET gene was detected. In this kindred MTC has occurred in the 4th to 5th decades of life, with a clinical spectrum in mutation-positive family members ranging from no disease and C-cell hyperplasia to carcinoma with lymph node metastasis; a 7-year-old with the mutation and a normal response to provocative testing was also identified. Management recommendations in children from families with clearly defined familial MTC may be individualized to reflect emerging genotype-phenotype correlations.

Adolescent↗
PubMed1993

Clinical performance of an extraction calcitonin radioimmunoassay.

An extraction radioimmunoassay of calcitonin (CT) was used to replace the direct radioimmunoassay, in which false-negative results (normal basal CT values but above normal ["positive"] results after pentagastrin stimulation) occurred in 26 to 30% of cases. During the past 6 years, 170 pentagastrin stimulation tests were performed in 135 patients at our institution. We reviewed the results to determine whether extraction radioimmunoassay yielded improvement. Of the 135 patients, 6 (4.4%) had indeterminate results of pentagastrin stimulation tests that consisted of normal basal levels but increased values after pentagastrin stimulation, a considerable improvement over the results with direct assay. Six other patients had indeterminate results of pentagastrin testing--increased basal CT levels but normal values after pentagastrin stimulation. Indeterminate results of pentagastrin tests occurred primarily in postoperative or preoperative patients with a family history of medullary thyroid carcinoma (MTC). The reasons for the indeterminate results were unclear, as was their importance as a prelude to disease, but two preoperative patients with indeterminate results eventually had positive results and were found to have MTC at operation. We conclude that extraction radioimmunoassay is more reliable than direct radioimmunoassay for the diagnosis of MTC. Determination of a basal CT value and of the CT value after pentagastrin stimulation is sufficient for diagnosing MTC.

Adult↗
PubMed1995

Progress in genetic screening of multiple endocrine neoplasia type 2A: is calcitonin testing obsolete?

BACKGROUND: Recent identification of RET mutations in multiple endocrine neoplasia type 2A (MEN 2A) allows a DNA-based approach to diagnosis in lieu of calcitonin sampling. To prospectively evaluate the efficacy of mutational analysis, genetic screening was performed in 124 patients (53 male, 71 female; age, 1 month to 80 years) at risk for MEN 2A referred over 3 months. METHODS: Analysis used genomic DNA and a polymerase chain reaction-based denaturing gradient gel electrophoresis strategy for mutation detection at RET codons 609, 611, 618, 620, and 634. Ninety-three of 124 patients were from established MEN 2A kindreds (group A), and screening replaced calcitonin testing. Twenty-one of 124 patients (group B) represented index cases of medullary thyroid carcinoma (MTC), and DNA analysis was performed to distinguish sporadic from hereditary disease. Ten patients (group C) had modest calcitonin elevations or had undergone thyroidectomy without confirming pathologic results, and testing was undertaken to clarify status. RESULTS: Group A: RET mutations occurred in 29 (median age, 10 years) of 93 patients, 14 of whom underwent thyroidectomy. No false-positive results were observed. Group B: five (24%) of 21 patients with seemingly sporadic MTC had RET mutations at codons 618 (one), 620 (one), or 634 (three). Group C: Nine of 10 patients with alleged MEN 2A had genetically negative results. CONCLUSIONS: Denaturing gradient gel electrophoresis reliably detects MEN 2A. Modest calcitonin elevations may lead to a false-positive diagnosis of MTC. DNA testing is the optimal approach to evaluating MEN 2A. Index cases of sporadic MTC should also undergo DNA analysis.

Adolescent↗
PubMed1995

The effectiveness of combined oral lysine acetylsalicylate and metoclopramide compared with oral sumatriptan for migraine.

Aspirin is commonly used to treat migraine attacks, although sumatriptan, a much more expensive treatment, is also effective. We compared a combination of lysine acetylsalicylate (equivalent to 900 mg aspirin) and 10 mg metoclopramide (LAS+MTC) with oral sumatriptan (100 mg) and placebo in 421 patients with migraine. LAS+MTC was as effective as sumatriptan with a decrease of headache from severe or moderate to mild or none of 57% and 53%, respectively, for the first migraine attack treated. Both treatments were better than placebo (success rate 24%, p < 0.0001). LAS+MTC was significantly more effective in the treatment of nausea than sumatriptan (p < 0.0001) and was better tolerated (adverse events in 18% and 28%, respectively, p < 0.05). LAS+MTC is as effective as sumatriptan in the treatment of migraine attacks. It is also much cheaper.

Administration, Oral↗
PubMed1997

The importance of early diagnosis in multiple endocrine neoplasia III: report of a case with thyroid C-cell hyperplasia.

Multiple endocrine neoplasia III (MEN III), also known as MEN IIb or mucosal neuroma syndrome, can often be recognized at an early age by its typical facies, marfanoid habitus, and characteristic mucosal neuromas. These features are usually present before development of the more serious, life-threatening complications that consist of medullary thyroid carcinoma (MTC) and pheochromocytoma. MTC associated with MEN III is generally aggressive with early metastasis. Early diagnosis is therefore crucial so that patients can be appropriately monitored for thyroid cancer with prompt thyroidectomy when indicated. Occasionally, patients present with C-cell hyperplasia of the thyroid, the histologic precursor to MTC. We describe a 16-year-old boy with mucosal neuromas, the typical facies of MEN III, gastrointestinal ganglioneuromatosis, and C-cell hyperplasia of the thyroid gland. Prompt thyroidectomy was performed, averting the risk of malignant transformation. Early clinical recognition of MEN III is crucial, as timely intervention can prevent the high mortality associated with MTC and pheochromocytoma.

Adolescent↗
PubMed1998

Inhibition of nitric oxide synthase causes elevation of hearing thresholds.

OBJECTIVE: Nitric oxide mediates the effects of excitatory amino acids in the central nervous system. The excitatory amino acids are thought to be the neurotransmitters at the cochlear hair cell-afferent nerve synapse. Nitric oxide synthase is present in spiral ganglion cells. This study investigated the role of nitric oxide in cochlear neurotransmission. METHODS: In gerbils, cochlear compound action potential thresholds were recorded before and after cochlear perfusions with control solutions of artificial perilymph solution and test solutions of S-methyl-L-thiocitrulline (MTC), a competitive inhibitor of nitric oxide synthase. Cochleas were also preperfused with L-arginine before perfusion with a mixture of MTC/L-arginine (to overcome competitive inhibition by MTC with L-arginine, the natural substrate of nitric oxide synthase). RESULTS: Cochlear perfusion with MTC caused significant elevations of compound action potential threshold of 51 dB as opposed to insignificant elevations of only 10 dB in control animals. An insignificant threshold shift of 9 dB was observed when L-arginine was coperfused with MTC. CONCLUSIONS: Nitric oxide is involved in neurotransmission/neuromodulation in the cochlea. Because nitric oxide is both a mediator of neurotoxicity and an initiator of apoptosis in the central nervous system, nitric oxide may play a role in these processes in the cochlea.

Action Potentials↗
PubMed1987

Medullary thyroid carcinoma in the Syrian golden hamster: an immunohistochemical study.

Spontaneously occurring thyroid neoplasms exhibiting solid and/or anaplastic growth patterns in the Syrian golden hamster have been thought to be derived from follicular cells. Eight neoplasms of this type have been analyzed immunohistochemically and have been classified as medullary thyroid carcinomas (MTC) on the basis of their content of calcitonin (CT). Well differentiated MTCs in this species were composed of polyhedral cells showing uniform CT immunoreactivity while the poorly differentiated MTCs most often had spindle patterns of growth with marked variation in CT immunoreactivity. Both well and poorly differentiated MTCs contained entrapped follicles which were CT negative. In contrast to MTC in the rat and in humans with familial MTC, the tumors in hamsters were not associated with C-cell hyperplasia. The Syrian golden hamster may, therefore, serve as a useful model to study the factors which are responsible for the development of spontaneous (non-familial) MTC.

Animals↗
PubMed1994

Functional longevity of the human peritoneum: how long is continuous peritoneal dialysis possible? Results of a prospective medium long-term study.

Long-term peritoneal dialysis requires the maintenance of the transport function of the peritoneal membrane, and appropriate studies of possible changes are necessary. The quantification of peritoneal mass transfer coefficients (MTCs) has been judged to be the ideal method for the evaluation of peritoneal diffusion. The aim of the present study was to show the results of the prospective evaluations in long-term continuous ambulatory peritoneal dialysis patients. We have studied the clinical incidents and peritoneal function of 56 patients who started continuous ambulatory peritoneal dialysis between 1980 and 1988, and have completed at least 3 years of follow-up. Ultrafiltration capacity was calculated with a standardized formula. All patients were studied for peritoneal diffusion of urea and creatinine at least once a year. The evaluation consisted of a kinetic study done by means of a peritoneal equilibration curve for urea and creatinine, applying a bicompartmental mathematical model to calculate the MTCs. The sequential mean values for urea-MTC did not show significant changes over the observation period (20.7 +/- 5.9 mL/min for the first year v 19.8 +/- 6 mL/min for the fifth year). Creatinine-MTC values showed a significant increase over this period in the paired data analysis. The decrease of the urea-MTC to creatinine-MTC ratio may be an early and appropriate index for measuring these changes when the individual values are in the normal range. On the other hand, peritoneal ultrafiltration capacity significantly decreased over this period (1,800 +/- 530 mL/d v 1,400 +/- 600 mL/d, P < 0.01). The high rate of accumulated days of peritoneal inflammation was related to these significant changes, and thus may be proposed to be a good prognostic index of long-term peritoneal survival. These long-term functional changes might be related to the effect of injuries on the preservation of the normal peritoneal structure. We conclude that after 5 to 11 years, the human peritoneum shows functional stability (diffusion and water transport) in patients with low rates of peritoneal inflammation. With a few exceptions, represented by patients with a high rate of peritoneal inflammation, long-term peritoneal dialysis accomplished its newly entrusted task.

Adolescent↗
PubMed2002

Inheritable forms of medullary thyroid carcinoma.

Medullary thyroid carcinoma (MTC) arises from parafollicular or C cells of the thyroid that produce calcitonin. It accounts for 5-10% of all thyroid cancers. Hereditary MTC represents 20-30% of all MTCs. It can be transmitted with an autosomal dominant pattern, either as a single entity, familial MTC, or it can arise as part of a multiple endocrine neoplasia (MEN) syndrome type 2A or 2B. The identification of hereditary MTC has been facilitated in recent years by the direct analysis of the ret proto-oncogene.

Animals↗
PubMed2000

Sustentacular cells in sporadic paraganglioma-like medullary thyroid carcinoma: report of a case with diagnostic and histogenetic considerations.

Sustentacular cells (SCs) are glial supporting cells of the fetal, adult normal, and neoplastic extra and adrenal human chromaffin cell lineage. SCs have also been identified in some cases of medullary thyroid carcinoma (MTC), raising both diagnostic and histogenetic problems. We report a rare case of a sporadic paraganglioma-like variant of MTC showing numerous S-100 protein and glial fibrillar acid protein (GFAP) positive SCs encircling neoplastic cells in a nesting (Zellballen) pattern similar to that observed in paragangliomas or pheochromocytomas. Although stromal amyloid deposits were only focally detected, diagnosis was immunohistochemically confirmed by immunoreactivity of the neoplastic cells for cytokeratin, CEA, calcitonin, chromogranin A, neuron-specific-enolase, and synapthopysin. As for the histogenesis of SCs, if we assume that MTC is a neural crest-derived tumor, it is likely that these cells reflect the ability of the common precursor cell to differentiate towards a sustentacular-type glial cell lineage in addition to the typical neuroendocrine one. This viewpoint is supported by the evidence that rare cases of MTC may contain neoplastic or supporting cells showing a multidirectional differentiation (usually neuroendocrine and melanocytic) that recapitulates the different cell lineages arising from the developing neural crests.

Carcinoma, Medullary↗
PubMed2000

Simultaneously occurring liver metastases of pheochromocytoma and medullary thyroid carcinoma--a diagnostic pitfall with clinical implications for patients with multiple endocrine neoplasia type 2a.

Malignant pheochromocytoma is an exceptional complication in patients with Multiple Endocrine Neoplasia Type 2a (MEN2a). In this paper, we report on a 53-year-old male patient with an evident RET gene germline mutation, who simultaneously developed hepatic metastases of medullary thyroid carcinoma (MTC) and pheochromocytoma. Comprehensive immunohistochemical investigations were performed to elaborate markers which could be useful for differentiating between MTC metastases and pheochromocytoma, respectively. Calcitonin and CEA, in particular cytokeratins and trefoil factor family 1 (TFF1), were detectable exclusively in MTC, whereas all the other markers revealed a comparable expression in both MTC and pheochromocytoma. The only clues that could indicate a potential malignant course were size, a lack of sustentacular cells and hyaline globules, and a focal spindle cell pattern in pheochromocytoma. Owing to a wide agreement in cellular differentiation and a lack of specific, routinely applicable markers for pheochromocytomas, a comprehensive and goal-directed immunohistochemistry is required to rule out pheochromocytoma metastasis in patients with MEN2a. A misinterpretation could lead to harmful clinical complications, as shown in the present case.

Adrenal Gland Neoplasms↗
PubMed1997

Effects of thyrotropin-releasing hormone and metoclopramide on PRL secretion in normally cycling and amenorrheic alcoholic women.

To assess the possible influence of alcoholism on the dopaminergic inhibitory control of prolactin (PRL) secretion, 10 mg of the dopaminergic antagonist metoclopramide (MTC), was injected i.v. in a group of eight healthy abstemious women (aged 28 +/- 6 (mean +/- S.E.) years) and in 16 aged-matched nondepressed female alcoholic subjects after 3-4 weeks of abstinence from alcohol. All normal controls and eight alcoholics had normal menstrual cycles and were tested in the early follicular phase (4-8 days), the remaining eight alcoholics were affected by amenorrhea (duration: 15 +/- 3 months). During the same period, all patients were also tested with TRH (200 micrograms in an i.v. bolus) to determine whether the pituitary PRL cell secretory capacity was preserved in alcoholics. The amenorrheic alcoholic group showed strikingly lower circulating estrogen levels than normally cycling groups. Similar basal PRL levels and PRL responses to TRH were observed in normal controls and normally cycling alcoholics, whereas basal and TRH-stimulated PRL levels were significantly higher in amenorrheic alcoholics. In contrast, the PRL response to MTC was significantly higher in cycling alcoholic patients than in normal controls and amenorrheic alcoholic subjects. However, when the statistical analysis of MTC test took into account the difference in estrogen levels among groups, the statistical differences in the PRL responses to MTC observed between normally cycling and amenorrheic alcoholics disappeared. These data suggest the presence of an enhanced dopaminergic inhibitory control of PRL secretion in 2-3 week abstinent alcoholics with normal menstrual cycles and normal circulating estrogen levels. In contrast, amenorrhea in abstinent alcoholics appears to be associated with an enhancement of PRL cell secretory activity.

Adult↗
PubMed2002

Controlled delivery of metoclopramide using an injectable semi-solid poly(ortho ester) for veterinary application.

In animal health care, current therapeutic regimens for gastrointestinal disorders require repeated oral or parenteral dosage forms of anti-emetic agents. However, fluctuations of plasma concentrations produce severe side effects. The aim of this work is to develop a subcutaneous and biodegradable controlled release system containing metoclopramide (MTC). Semi-solid poly(ortho ester)s (POE) prepared by a transesterification reaction between trimethyl orthoacetate and 1,2,6,-hexanetriol were investigated as injectable bioerodible polymers for the controlled release of MTC. MTC is present in the polymeric matrix as a solubilised form and it is released rapidly from the POE by erosion and diffusion because of its acidic character and its high hydrosolubility. If a manual injection is desired, only low molecular weight can be used. However, low molecular weight POEs release the drug rapidly. In order to extend polymer lifetime and decrease drug release rate, a sparingly water-soluble base Mg(OH)(2) was incorporated to the formulation. It was possible to produce low molecular weight POE that can be manually injected and releasing MTC over a period of several days.

Animals↗
PubMed1997

Comparison between magnetization transfer contrast and fast spin-echo MR imaging of degenerative disease of the cervical spine at 0.3 T.

We compared magnetization transfer contrast (MTC) with gradient recalled echo (GRE) magnetic resonance imaging (MRI) and fast spin-echo (FSE) MRI of the degenerative cervical spine at 0.3 T. Fifty patients with suspected degenerative disease of the cervical spine were prospectively evaluated. Multislice sagittal and axial images of the cervical spine were obtained using MTC GRE sequence [repetition time (TR)/echo time (TE)/flip angle = 750/23/25 degrees] and FSE sequence with peripheral gating (TR/effective TE = 2000-4000/120). Quantitatively, FSE showed higher signal-to-noise ratio and superior disk contrast between normal and degenerative disks, while MTC images showed superior contrast-to-noise ratio for the cerebrospinal fluid (CSF) versus cord and superior CSF homogeneity. In qualitative analysis, similar results were obtained. In conclusion, FSE and MTC GRE sequences are MRI techniques of imaging the cervical spine that have different characteristics and supplement each other in the diagnostic imaging of degenerative disease of the cervical spine.

Adult↗
PubMed2001

Quality of life in patients at risk of medullary thyroid carcinoma and followed by a comprehensive medical network: trends for future evaluations.

BACKGROUND: As shown in a previous study, the knowledge of the genetic risk in individuals belonging to families at risk of medullary-thyroid carcinoma (MTC) could be associated with impaired quality of life (QoL). PATIENTS AND METHODS: In the present study, we compared the QoL scores obtained in the same period with the subjective quality of life profile (SQLP): in 82 individuals at risk of MTC who had been tested for Ret-mutations; in 200 women at risk of familial breast/ovarian cancer syndrome (BOC); and in a control population of 3,501 healthy volunteers. RESULTS: Significant differences were observed in favour of healthy volunteers as well as individuals at risk of MTC, over women at risk of BOC (mean scores: 0.89, 0.85, and 0.64, respectively, P < or = 0.001), but QoL scores were not statistically different between individuals at risk of MTC and the control population (P = 0.2). However, they were significantly inferior in the subgroup of germline Ret-mutation carriers, as compared to the control population (mean scores: 0.73 and 0.89, P = 0.04). In the latter, the relationships with the children and the family were the most important facets of their QoL. CONCLUSION: Our results confirm the potentially negative impact of the knowledge of the genetic risk of cancer and its consequences in terms of morbidity and follow-up, on the QoL in people followed at oncogenetic visits.

Adolescent↗
PubMed2002

Risk factors for medullary thyroid carcinoma: a pooled analysis.

OBJECTIVE: To investigate risk factors for medullary thyroid cancer (MTC). METHODS: We conducted a pooled analysis of 14 case-control studies from Europe, North America, and Asia, including 67 medullary cancers (43 women and 24 men) diagnosed in ten studies. Of the original 4776, we selected five controls per case matched on study, gender, and age. The pooled odds ratios (OR) were estimated using conditional logistic regression. RESULTS: Education, weight, and body mass were not associated with MTC, but a significant positive relationship was seen with height (OR = 2.6 for highest vs lowest tertile). Significant excess risks were associated with a history of thyroid nodules (OR = 12), hypertension (OR = 2.3), gallbladder disease (OR = 4.3), and allergies (OR = 2.2). Among current smokers, a decreased risk of MTC was observed with increasing number of cigarettes. The risk was significantly elevated among women having a first birth after age 25 years, but no clear pattern emerged for other reproductive factors. CONCLUSIONS: Although the number of MTC was small, we detected several significant associations, including prior thyroid and other diseases.

Adult↗
PubMed2002

An early increase in serum levels of C-reactive protein is an independent risk factor for the occurrence of major complications and 100-day transplant-related mortality after allogeneic bone marrow transplantation.

We monitored levels of C-reactive protein (CRP) in 96 consecutive adult allogeneic BMT patients (age 15-50 years) transplanted in our unit. Major transplant-related complications (MTC) occurred in 32% of cases and included: hepatic veno-occlusive disease, pneumonitis, severe endothelial leakage syndrome and >II acute GVHD. Transplant-related mortality (TRM) before day 100 post-BMT was 13.5%. Variables included in a stepwise logistic regression model were: gender, age, disease category, donor type, T cell depletion, TBI, use of growth factors, bacteremia, mean CRP-levels >50 mg/l between days 0 and 5 (CRP day 0-5) and >100 mg/l between days 6 and 10 (CRP day 6-10) post-BMT. Only high CRP-levels (for MTC and TRM) (P < 0.001) and donor-type (for TRM) (P= 0.02) were independent risk factors. The estimated probability for MTC was 73% (CRP day 6-10 >100 mg/l) vs 17% (CRP day 6-10 <100 mg/l). Using the same cut-off levels, the probabilities for TRM were 36.5% vs 1% in the identical sibling donor situation and 88% vs 12.5% in other donor-type transplants. We conclude that the degree of systemic inflammation, as reflected by CRP-levels, during the first 5-10 days after BMT identifies patients at risk of MTC and TRM. Our data may be useful in selecting patients for clinical trials involving pre-emptive anti-inflammatory treatment.

Adolescent↗