Lesion-based indicators predict long-term outcomes of pheochromocytoma and paraganglioma- SIZEPASS

Aim

We seek a simple and reliable tool to predict malignant behavior of pheochromocytoma and paraganglioma (PPGL).

Methods

This single-center prospective cohort study assessed size of primary PPGLs on preoperative cross-sectional imaging and prospectively scored specimens using the Pheochromocytoma of the Adrenal Gland Scaled Score (PASS). Multiplication of PASS points with maximum lesion diameter (in mm) yielded the SIZEPASS criterion. Local recurrence, metastasis or death from disease were surrogates defining malignancy.

Results

76 consecutive PPGL patients, whereof 58 with pheochromocytoma and 51 female, were diagnosed at a mean age of 52.0 ± 15.2 years. 11 lesions (14.5%) exhibited malignant features at a median follow-up (FU) of 49 months (range 4-172 mo). Median FU of the remaining cohort was 139 months (range 120-226 mo). SIZEPASS classified malignancy with an area under the curve (AUC) of 0.97 (95%CI 0.93-1.01; p<0.0001). Across PPGL, SIZEPASS >1000 outperformed all known predictors of malignancy, with sensitivity 91%, specificity 94%, and accuracy 93%, and an odds ratio of 72 fold (95%CI 9-571; P<0.001). It retained an accuracy >90% in cohorts defined by location (adrenal, extra-adrenal) or mutation status.

Conclusions

The SIZEPASS>1000 criterion is a lesion-based, clinically available, simple and effective tool to predict malignant behavior of PPGLs independently of age, sex, location or mutation status.

Oncologic resection achieving r0 margins improves disease-free survival in parathyroid cancer

BACKGROUND

Parathyroid cancer has a poor mid-term prognosis, often because of local recurrence, observed in half of all patients. Modern diagnostic workup increasingly enables a preoperative diagnosis of parathyroid cancer. There is limited evidence that more comprehensive oncologic surgery can reduce the risk of local recurrence. This study aims to identify the best specific surgical approach in parathyroid cancer.

METHODS

This observational cohort study comprises 19 consecutive patients who had undergone oncologic or nononcologic resection for parathyroid cancer. Baseline parameters were compared by using univariate analysis; outcomes were assessed by χ (2) testing and Kaplan-Meier statistics.

RESULTS

Fifteen of 19 patients were primarily operated on in our tertiary center between 1996 and 2013, and four were referred for follow-up because of their cancer diagnosis. Patient cohorts defined by histologic R-status were comparable for established risk factors: sex, calcium levels, low-risk/high-risk status, and presence of vascular invasion. Oncologic resections were performed in 13 of 15 patients primarily treated in the center and 0 of 4 treated elsewhere (χ (2) = 5.6; p < 0.01). R0 margins were achieved in 11 of 13 (85 %) undergoing oncologic resection and 1 of 6 (17 %) undergoing local excision (χ (2) = 8.1; p < 0.01). R0 margins and primary oncologic resection were associated with higher disease-free survival rates (χ (2) = 7.9; p = 0.005 and χ (2) = 4.7; p = 0.03, respectively). Revision surgery achieved R0 margins in only 2 of 4 (50 %) of patients.

CONCLUSIONS

In parathyroid cancer, a more comprehensive surgery (primary oncologic resection) provides significantly better outcomes than local excision as a result of reduction of R1 margins and locoregional recurrence.

Abstract 611: Blocking CD40-TRAF6 Signaling is a Novel Therapeutic Target in Obesity-Associated Insulin Resistance

The immune system plays an instrumental role in obesity and insulin resistance. Here we unravel the role of the co-stimulatory molecule, CD40, and its signaling intermediates, TNF-Receptor-Associated-Factors (TRAFs), in diet-induced obesity (DIO). Although not exhibiting increased weight gain, male CD40-/- mice in DIO displayed worsened insulin resistance, as compared to wild type mice. This was associated with excessive inflammation of adipose tissue (AT), characterized by increased accumulation of CD8+ T cells and M1 macrophages, and enhanced hepatosteatosis. Mice with deficient CD40-TRAF2/3/5 signaling in MHCII+ cells exhibited a similar phenotype in DIO as CD40-/- mice. In contrast, mice with deficient CD40-TRAF6 signaling in MHCII+ cells displayed no insulin resistance, and showed a reduction in both AT inflammation and hepatosteatosis in DIO. To prove the therapeutic potential of inhibition of CD40-TRAF6 in obesity, DIO mice were treated with a small-molecule inhibitor that we designed to specifically block CD40-TRAF6 interactions; this improved insulin sensitivity, reduced AT inflammation and decreased hepatosteatosis. Our study reveals that the CD40-TRAF2/3/5 signaling pathway in MHCII+ cells protects against AT inflammation and metabolic complications associated with obesity, whereas CD40-TRAF6 interactions in MHCII+ cells aggravate these complications. Inhibition of CD40-TRAF6 signaling by our newly developed compound may provide a novel therapeutic option in obesity-associated insulin resistance.

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Changing incidence and management of penetrating neck injuries in the South East London trauma centre

INTRODUCTION

A total of 17 cases of penetrating neck injury were managed by the otolaryngology team at King's College Hospital over a 3-year period in the 1980s. In April 2010 King's College Hospital became the major trauma centre for South East London. This prospective cohort study compares the incidence, changing demographic features and treatment outcomes of penetrating neck trauma in South East London over the previous 23 years.

METHODS

Data were collected over a 12-month period (April 2010 to March 2011) and a selective management protocol was introduced to standardise initial investigations and further treatment.

RESULTS

The past 23 years have seen a 550% increase in the incidence of penetrating neck injuries in South East London, with a marked increase in gun crime. Only 38% of cases underwent negative neck exploration in 2011 compared with 65% in 1987. Selective conservative management based on the absence of haemodynamic instability or radiological findings reduces length of hospital stay, lightens surgical workload and cuts costs without affecting morbidity or mortality.

CONCLUSIONS

The increased incidence of penetrating neck injury is a reflection of more interpersonal violence rather than a consequence of the larger South East London trauma centre catchment area. Tackling this problem requires focus on wider issues of community prevention. Sharing of data between the four London trauma centres and the police is needed to help prevent interpersonal violence and develop a universal treatment algorithm for other institutions to follow.

INT-2 gene amplification in differentiated human thyroid cancer

Oncogene amplification is frequent in many epithelial tumors and often associated with advanced tumor progression. In different epithelial neoplasias it helps to provide prognostic information on individual patients. The present study was performed to evaluate the hitherto unknown prevalence of INT-2 gene amplification and its potential usefulness as prognostic marker in patients with human thyroid cancer. We used differential quantitative polymerase chain reaction and fluorescent DNA technique as a reliable method to detect low copy-number amplification of oncogenes from archival carcinoma specimens. Sequences from the int-2 gene and the single copy gamma-interferon gene were amplified simultaneously by PCR and quantified on a fluorescence activated sequencer. Native tumor tissue from 63 patients with differentiated thyroid cancer (43 papillary, 3 oncocytary, and 17 follicular) and from 12 goiters was analyzed by differential quantitative polymerase chain reaction. The study group contained many far advanced tumors. 40% of tumors were recurrent, 35% were staged T4 tumors and 70% presented with lymph node metastases. The prevalence of INT-2 amplification was 12% for follicular and 7% for papillary carcinomas. In goiter tissue no amplification was found. Amplification was only 2-4fold in positive cases. Low grade amplification is of no apparent importance in differentiated thyroid cancer.

Mutation and methylation analysis of TP53 in adrenal carcinogenesis

AIM

To investigate the role of coding region mutation and promoter hypermethylation of TP53 in adrenocortical cancer formation.

METHODS

Twenty sporadic adrenocortical cancers (ACCs) and five normal adrenal tissue samples were available for analysis. Coding region mutation of TP53 in 20 ACCs was examined by polymerase chain amplification using intronic primers for exons 2-11 and direct sequencing of the product. In 10 ACCs and five normal adrenal tissue specimens, methylation of the 16 CpG sites within the TP53 promoter was examined using bisulphite methylation sequencing.

RESULTS

Coding region mutation in TP53 was demonstrated in 5 of 20 ACCs. There were four mis-sense mutations and one frameshift mutation. Four of 5 patients with a TP53 mutation had metastases at diagnosis or detected soon thereafter and 3 of 4 died of disease within 12 months of surgical resection. No methylation was seen in the TP53 promoter in 10 ACC and the five normal adrenal tissues examined.

CONCLUSION

Coding region mutation in TP53 occurs in 25% of ACCs with a trend toward a poorer prognosis. Promoter methylation of TP53 is not present in ACC as a mechanism for tumour suppressor gene (TSG) inactivation and, therefore, other genes in the 17p13 region are implicated in adrenal carcinogenesis.

No association of IL-1beta C + 3954 T polymorphism and thyroid disease

Interleukin-1 is a potent pro inflammatory agent, has a direct influence on human thyroid cell function, and modulates cell growth in differentiated thyroid carcinoma cell lines. To evaluate whether a polymorphism on the IL-1beta gene has an influence on the incidence of thyroid disorders, we analyzed the C + 3954 T polymorphism in DNA samples of 673 individuals. 414 venous blood samples were collected from patients suffering from thyroid diseases (Graves' disease n = 53, euthyroid or hyperthyroid non-immunogenic benign thyroid disorders n = 240, thyroid carcinoma n = 121). 259 persons without thyroid disease served as a control. There was no statistically significant association between either of the thyroid alterations or functional conditions on the one hand and the examined genetic polymorphism on the other. Because of the large number of samples tested we can conclude with a high degree of confidence that there is no association between the genotype and the surveyed diseases.

Multiple neuroendocrine tumors of the pancreas associated with pancreas divisum

Pancreas divisum is the most common congenital anomaly of the pancreas, characterized by missing fusion of the ventral and dorsal pancreatic duct. It may cause pancreatitis, but is rarely associated with malignancy.We report herein for the first time the rare association, in a symptomless patient, of multiple neuroendocrine tumors of the pancreas with pancreas divisum and a failure of the exocrine system. Diagnosis was made incidentally by routine abdominal ultrasound. Laboratory examinations and a fine-needle aspiration revealed the neuroendocrine nature of the tumor. Spleen-preserving left pancreas resection was performed, with evidence of multiple neuroendocrine tumors of the pancreas with the typical histological characteristics. Eighteen months later the patient is still free of tumor burden.

[Economic restraints shorten the length of hospital stay: thyroid operation as a model case]

INTRODUCTION

Decreasing the length of stay is a possible means of cost control in the medical system. Therefore we performed a study to test the feasibility of reducing hospital stay to 2 days after thyroid operation.

METHODS

In a controlled prospective trial, 238 patients were randomly assigned to group A (2 days of stay) or group B (more than 2 days). Studied were medical standard, practicability, patient acceptance, and quality of life.

RESULTS

Of those in group A, 56.6% did not leave the hospital at the scheduled 2nd day post operation. Reasons were preoperative hyperthyroidism ( P<0.011), postoperative hypocalcemia ( P<0.03), or unspecific disturbances. In group B, 28% of the patients left before the established borderline of 3-4 days, and only 35% left on the 2nd postoperative day.

CONCLUSION

Reduced length of stay has no negative influence on medical standards. The quality of life of patients leaving the hospital on the 2nd postoperative day was significantly higher. Reducing hospital stay after thyroid operation to 2 postoperative days is desirable and possible without a loss in quality of care, except in case of postoperative complications or unspecific complaints.

Prophylaxis of CMV disease by ganciclovir (DHPG) in seronegative recipients of renal allograft from seropositive donors

In an open-label randomized study of prophylactic treatment by ganciclovir, 23 seronegative recipients of kidney allograft from seropositive donors were randomized to receive from day 14 to day 28 after transplantation either no treatment (n = 11) or ganciclovir, 5 mg/kg twice daily (n = 12). Both groups were similar in age, immunosuppressive therapy, number of acute rejections and in steroid bolus. Seroconversion occurred in ten patients of the control group (91%) and in ten of the ganciclovir group (84%). CMV disease occurred in ten patients of the control group (91%) and in eight patients of the ganciclovir group (66%), three of whom had asymptomatic viraemia. The delay between transplantation and onset of CMV disease was significantly increased by ganciclovir prophylaxis (78.5 +/- 7.7 vs 46.5 +/- 7.5 days, P < 0.05). We conclude that in renal transplant recipients at risk of CMV disease, ganciclovir prophylaxis delays the onset of the disease and seems to decrease its incidence and its severity.

The actual role of classic bilateral cervicotomic approach for primary hyperparathyroidism in the era of minimally invasive surgery

Recent advances in preoperative localisation of parathyroid adenomas and intraoperative prove of complete removal of hyperfunctioning parathyroid tissue have fostered less invasive operative procedures which directly target the diseased gland. Such strategies have partially replaced the previous gold standard procedure of bilateral neck exploration. We herein report on our own series of 1099 consecutive operations for primary hyperparathyroidism performed in a 16 year period and provide information and arguments for primary bilateral exploration in selected cases. 97.1% of patients were cured by the primary operation. From 1999 through 2001, 200 patients underwent bilateral neck exploration, whereas 63 unilateral operations were performed (33 patients were treated by minimally invasive video-assisted parathyroidectomy (MIVAP) and 30 by minimally invasive open parathyroidectomy (MIOP). In the remaining 200 patients minimally invasive unilateral parathyroid surgery was not feasible due to concomitant goiter (n = 102), lack of preoperative localisation (n = 30), previous thyroid surgery (n = 10), suspected multiglandular disease (n = 10), or other reasons (n = 8). In 40 patients the decision for bilateral neck exploration was made despite feasibility of a unilateral approach.

CONCLUSION

Whereas unilateral exploration produced excellent cure rates in older patients, it is not recommended in patients with a high likelihood of multiglandular disease, presence of a large or multinodular goitre, high PTH levels, giant adenoma, unclear MIBI scans or an unreliable OPTH assay. Contrasting recent reports on a dramatic shift of technique towards minimally invasive procedures unilateral parathyroid surgery may not be preferably advisable in a majority of patients from countries with insufficient iodine supplementation.

[Monitoring the recurrent laryngeal nerve as a routine measure in thyroid gland surgery]

Intra-operative monitoring of the recurrent laryngeal nerve by electromyography of the inner laryngeal muscles facilitates the nerves preparation. The positive and negative predictive values of the method with regard to vocal cord function have not sufficiently been examined. Prospective randomized data concerning the usefulness with regard to permanent nerve palsy rates are lacking. The impressive reduction in palsy rates over the last 20 years is due to routine preparation and protection of the visualized nerve. This principle must not be abandoned. Depending on the setting, neuromonitoring may be a valuable help. It is not an obligation in thyroid surgery.

[Neurostimulation of the recurrent laryngeal nerve--a routine method in thyroid gland surgery?]

INTRODUCTION

Thyroid operations belong to the most frequent procedures in Germany (100,000/year). An important quality parameter is the incidence of postoperative recurrent nerve paralysis. Intraoperative identification by visualization of the nerve with a paralysis rate of 1% is the present gold standard in dedicated centers.

PROBLEM

Can this results be further improved by use of an intraoperative neuromonitoring system (NM).

RESULTS

The use of NM is helpful in difficult situations (recurrent goiter, advanced carcinoma, anatomic variants), but a quality improvement is not yet proven.

CONCLUSION

NM can not replace the current nerve identification by meticulous preparation of anatomic structures. It should be used at the discretion of the operative surgeon.

The determination of ketone bodies: preanalytical, analytical and physiological considerations

The arterial ketone body ratio is calculated as the ratio of arterial levels of acetoacetate/beta-hydroxybutyrate. It correlates with survival in experimental hemorrhagic shock and outcome after liver surgery and myocardial infarction. Procedures for determination of ketone bodies are often laborious and unreliable. As yet the relationship between results from arterial and venous samples is unclear. We therefore describe the determination of the ketone bodies acetoacetate and 3-hydroxybutyrate by an easy, reliable, rapid, inexpensive enzymatic assay using 3-hydroxybutyrate dehydrogenase (E.C. 1.1.1.30) in a semi-automated setting that does not require deproteinization. Preanalytical parameters, including separation from corpuscular elements within 1 h and storage on ice for less than 1 h, must be strictly observed to avoid rapid decay of acetoacetate by spontaneous decarboxylation. The assay has high sensitivity, specificity (+/-5%), and precision (CV <2.5%) with a measurable range of 5-500 micromol/l for either ketone body, and requires only 23.5 microl of plasma. At temperatures below -17 degrees C plasma may be stored for prolonged periods. Results from prospectively scheduled simultaneous sampling of arterial blood and venous blood from the right atrium in 100 consecutive patients with severe multiple trauma (mean Injury Severity Score 38+/-13) support the view that the lung has no role in ketone body metabolism. We conclude that central venous blood can safely be substituted for arterial blood for determination of the ketone body ratio.

Genetic determinants of IL-6 expression levels do not influence bone loss in inflammatory bowel disease

Bone loss in inflammatory bowel disease (IBD) is presumed to be mediated by inflammation. Increased levels of the multifunctional cytokine IL-6 in inflammatory diseases have been proposed to be the link in such "inflammation-mediated osteopenia." A recently described G/C polymorphism with an effect on transcription rate and plasma levels of IL-6 suggests a genetically determined difference in the degree of the IL-6 response to stressful stimuli between individuals. This study aimed to assess the frequency of genotypes and haplotypes of the G/C polymorphism of IL-6 in IBD patients. A further aim was to assess whether carriage of the potentially protective CC genotype is favorable with respect to the development of bone disease in IBD. The IL-6 polymorphism was typed in 105 IBD patients and 113 healthy controls. Bone mineral density was evaluated at baseline and after a prospective 2-year-follow-up. The favorable CC genotype with decreased IL-6 release was not underrepresented in IBD patients compared to healthy controls. Carriage of this genotype was not protective with respect to the development of bone disease, either for the bone mineral density at baseline or for the prospectively observed bone loss. Within the subgroup of patients who did not receive steroids during follow-up, the prospectively observed bone loss was even slightly higher in CC carriers, but differences did not reach significance. Genetically determined differences in the degree of the IL-6 response to stressful stimuli are no major predictors for the degree of bone disease in IBD patients.

Lysophosphatidic acid, a novel lipid growth factor for human thyroid cells: over-expression of the high-affinity receptor edg4 in differentiated thyroid cancer

Lysophosphatidic acid (LPA) is a small lipid mediator with pleiotropic biological activities, e.g., the regulation of cellular proliferation and various aspects of cellular physiology. Signal transduction is achieved by binding to 2 high-affinity receptors, EDG2 and EDG4, and a group of low-affinity receptors, EDG1-7, all belonging to the superfamily of G protein-coupled receptors. We examined the growth-regulatory effects of LPA in primary cultures of 8 goiters and 1 papillary thyroid cancer. We further assessed mRNA expression of high-affinity receptors EDG2 and EDG4 in 14 normal thyroids, 29 papillary thyroid cancers, 7 follicular thyroid cancers and 13 goiters by quantitative RT-PCR. We also identified mRNA expression of phospholipase A(2) and LPA acyltransferase in fresh thyroid tissues derived from various sources. At concentrations of 10, 50 and 150 microM, LPA induced a 2-fold rise of proliferation (p < 0.001) and acted as strongly as thyrotropin. The combination of LPA and TSH produced significant synergistic effects compared with each substance alone (p < 0.05). Normal thyroid, goiter and papillary or follicular thyroid cancer expressed 2 high-affinity cognate LPA receptors, EDG2 and EDG4. EDG4 receptor mRNA expression was increased 3-fold in differentiated thyroid cancer (p < 0.01), both papillary (p < 0.01) and follicular (p < 0.05), compared to normal thyroid or goiter. Overall expression of EDG2 receptor was unchanged in malignancy; however, increased EDG2 expression in individual samples correlated with lymphonodular metastasis (p = 0.01). Thus, lipid mediators are a novel class of factors involved in the control of proliferation in the human thyroid. Altered mRNA expression of the high-affinity LPA receptor EDG4 suggests a role in the pathogenesis of differentiated thyroid cancer.

Lysophosphatidic acid, a novel lipid growth factor for human thyroid cells: over-expression of the high-affinity receptor edg4 in differentiated thyroid cancer

Lysophosphatidic acid (LPA) is a small lipid mediator with pleiotropic biological activities, e.g., the regulation of cellular proliferation and various aspects of cellular physiology. Signal transduction is achieved by binding to 2 high-affinity receptors, EDG2 and EDG4, and a group of low-affinity receptors, EDG1-7, all belonging to the superfamily of G protein-coupled receptors. We examined the growth-regulatory effects of LPA in primary cultures of 8 goiters and 1 papillary thyroid cancer. We further assessed mRNA expression of high-affinity receptors EDG2 and EDG4 in 14 normal thyroids, 29 papillary thyroid cancers, 7 follicular thyroid cancers and 13 goiters by quantitative RT-PCR. We also identified mRNA expression of phospholipase A(2) and LPA acyltransferase in fresh thyroid tissues derived from various sources. At concentrations of 10, 50 and 150 microM, LPA induced a 2-fold rise of proliferation (p < 0.001) and acted as strongly as thyrotropin. The combination of LPA and TSH produced significant synergistic effects compared with each substance alone (p < 0.05). Normal thyroid, goiter and papillary or follicular thyroid cancer expressed 2 high-affinity cognate LPA receptors, EDG2 and EDG4. EDG4 receptor mRNA expression was increased 3-fold in differentiated thyroid cancer (p < 0.01), both papillary (p < 0.01) and follicular (p < 0.05), compared to normal thyroid or goiter. Overall expression of EDG2 receptor was unchanged in malignancy; however, increased EDG2 expression in individual samples correlated with lymphonodular metastasis (p = 0.01). Thus, lipid mediators are a novel class of factors involved in the control of proliferation in the human thyroid. Altered mRNA expression of the high-affinity LPA receptor EDG4 suggests a role in the pathogenesis of differentiated thyroid cancer.

Activin A and activin receptors in thyroid cancer

Proliferation is controlled by a network of mitogenic and growth inhibitory factors. Transforming growth factor-beta1 (TGF-beta1) and activin A are the most important growth inhibitors of benign follicular epithelial cells of the human thyroid. The effects of these substances on malignant primary thyrocytes are not known. We have examined the growth regulatory effects of activin A and TGF-beta1 in primary cultures derived from four papillary cancers, two follicular thyroid cancers, and three benign thyroid tissues. Malignant cells demonstrated resistance to activin and TGF-beta1 or reversal to a weak but significant mitogenic effect (p < 0.001). We also evaluated the activin receptor transcription pattern. Isoforms alk4-1, 4-2, and 4-3 were found in benign (n = 12) and malignant (n = 22) tissues. Two subtypes of type I and type II activin receptors were demonstrated. Semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) demonstrated a significant threefold downregulation of alk4-1 receptors in papillary (n = 25) and follicular (n = 18) thyroid cancers as compared to normal thyroids (n = 12) (p < 0.001). To our knowledge these are the first data to demonstrate reversal of activin and TGF-beta1 effects in thyroid malignancy and to demonstrate changes of the type Ib activin receptor expression in thyroid malignancy.

Coral reef aorta: a long-term study of 21 patients

Coral reef aorta is a rare calcifying disease of the juxtarenal and suprarenal aorta. We report here our surgical experience in treating 21 patients, with a mean follow-up of 4 years and 7 months. Both genders were equally affected. Ten male (48%) and 11 female (52%) patients with a mean age of 54.6 years (range 42-76 years) underwent surgery. The main symptoms were limb claudication (n = 11, 52%), renovascular stenosis (n = 9, 43%) with concurrent renovascular hypertension (n = 5, 24%), and angina abdominalis (n = 7, 33%). Most patients had multiorgan vascular disease such as iliofemoral arterial occlusive disease (n = 14, 66%), coronary artery obstruction (n = 8, 38%), or obstruction of the carotid artery (n = 6, 28%). Risk factors did not differ between coral reef patients and those with other occlusive vascular diseases. All patients were treated through vascular operations, including open thromboendarterectomy of the suprarenal (n = 9, 43%), infrarenal (n = 4, 19%), or supra- and infrarenal aorta (n = 8, 38%), and thromboendarterectomy of the following vessels: celiac artery (n = 7, 33%), superior mesenteric artery (n = 12, 57%), inferior mesenteric artery (n = 3, 14%), unilateral renal artery (n = 3, 14%), or bilateral renal artery (n = 9, 43%). Bypass reconstructions were performed in 39% (n = 8). A thoracoabdominal approach was used in 14 patients (67%) and a median laparotomy in 7 (33%). Our results show that coral reef aorta is not confined to either gender. It appears most frequently in the context of general atherosclerotic disease and patients benefit from timely diagnosis and operation before onset of severe, life-threatening visceral and renal complications.

Activin A and activin receptors in the human thyroid: a link to the female predominance of goiter?

Activin A belongs to the TGF-beta family of growth factors involved in control of tissue formation by growth inhibition and to a family of hormones involved in human reproduction. Serum levels of dimeric activin A display a sexual dimorphism with significantly higher circulating hormone concentrations in men than in women after menopause. Since goiter is far more frequent in women than in men, we investigated the role of this sex-related growth factor in the human thyroid. Primary cultures were obtained from 3 patients with goiter, and 4 with recurrent goiter. Activin A significantly inhibited the proliferation of human thyroid follicular epithelial cells in vitro in concentrations between 0.5 and 50 ng/ml and was almost as potent as TGFbeta-1. Analysis in native tissues from 12 normal thyroids, 16 goiters, and 5 Graves thyroids demonstrated mRNA expression of the activin subunit betaA, TGFbeta-receptor type I and II, activin receptors type I receptors alk2 and alk4, and activin type II receptors actRII and actRIIb. Isoform analysis of the major functional type I activin receptor alk4 revealed the full-length transcript SKR2-1 and transcripts for the partially truncated proteins SKR2-2 and SKR2-3 in normal thyroids and goiters. Semi-quantitative RT-PCR revealed a significant 2.5-fold decrease of mRNA for alk4-1 type I activin receptors in goiter as compared to normal thyroid (p < 0.05), whereas expression of the type II receptor actRII was unchanged. These data identify a novel growth inhibitory pathway by activin in the human thyroid. Down-regulation of activin receptor type lb in goiter hints towards end-organ changes which could contribute to deficient growth inhibition. These data provide a mechanistic model how the sexually dimorphic hormone activin A may protect males from goitrogenesis.

Genetic factors determine extent of bone loss in inflammatory bowel disease

BACKGROUND & AIMS

Although bone loss and osteoporosis are well-known long-term sequelae of inflammatory bowel disease (IBD), the risk factors for increased bone loss have not been identified. Balances of pro- and anti-inflammatory cytokines influence mechanisms of both chronic inflammation and bone resorption. The aim of this study was to identify genetic risk factors for rapid bone loss in IBD patients as a model of disease- and inflammation-associated bone loss.

METHODS

Multiple clinical parameters, biochemical markers of bone metabolism (vitamin D, parathyroid hormone, N-terminal telopeptide of type-I collagen, desoxypyridinoline, bone alkaline phosphatase), and bone mineral density were prospectively assessed in 83 IBD patients over 1.6+/-0.3 years. Eighty-six healthy bone marrow donors served as controls for allelotyping. The allele status of the interleukin 1 receptor antagonist (IL-1ra), IL-6, heat shock protein 70-2 (hsp 70-2), and heat shock protein 70-hom (hsp hom) genes was typed and correlated with clinical course of IBD and extent of bone loss.

RESULTS

The extent of bone loss was not correlated to clinical severity of disease or application of corticosteroids. Noncarriage of the 240-base pair allele of the IL-1ra gene and carriage of the 130-base pair allele of IL-6 were independently associated with increased bone loss. Genetic variations of the hsp genes were not associated with degree of bone loss. The combined presence of the named risk factors was significantly associated with increasing bone loss.

CONCLUSIONS

Genetic variations in the IL-6 and IL-1ra gene identify IBD patients at risk for increased bone loss.

Multivisceral fibromuscular dysplasia in childhood: case report and review of the literature

We report here a 9-year-old girl with fibromuscular dysplasia of many muscular arteries including both renal and internal carotid arteries, the celiac artery, superior mesenteric artery, and one external carotid artery. She suffered from severe renovascular hypertension with beginning secondary cardiac decompensation, typical angina abdominalis, and neurological signs, including severe headaches and hemianopsia. Surgery was performed for all major vessels and the outcome is good 2.5 years after the operation. The clinical presentation, differential diagnosis, and treatment options of fibromuscular dysplasia in childhood are discussed and the literature is reviewed.

Growth regulation of thyroid and thyroid tumors in humans

In a study of growth regulation of the human thyroid gland and thyroid tumors we investigated the impact of iodine and that of the thyroid-specific growth-stimulating hormone TSH. Further studies included locally active growth factors such as the epidermal growth factor, insulin-like growth factor, and tissue transforming growth factors alpha and beta. In addition to studies of growth regulation by the various growth factors in mostly normal thyrocytes, the impact of tumor-specific mutations in oncogenes and tumor-suppressor genes was investigated. The results demonstrated distinct changes in tissue specificity and sensitivity to external stimuli. This rather complex view on thyrocyte growth regulation may be confusing, but it describes the biologic reality more precisely. Increased knowledge of the regulatory processes may lead to the development of new tumor- and patient-specific therapeutic approaches, especially for preventing benign goiter recurrence and for treating follicular and papillary thyroid cancers.

Complete sequencing and mRNA expression analysis of the MEN-I gene in adrenal myelolipoma

The molecular pathogenesis of adrenal myelolipoma is unclear. Endocrine activity of these tumors and association with other endocrine tumors have stimulated the hypothesis that it may belong to the group of sporadic tumors caused by defects of the gene responsible for multiple endocrine neoplasia type I (MEN-I). DNA of blood and tumoral sections from two patients with adrenal myelolipoma were analyzed by examination of variable number of tandem repeats (VNTR) loci PYGM, D11S987, D11S480, and D11S449 on chromosome 11q13 and by complete direct DNA sequencing of all coding exons and splice junctions of the MEN-I gene. Menin expression was examined by RT-PCR. RT-PCR did not detect menin expression in one adrenal myelolipoma. No loss of heterozygozity on chromosome 11q13 was identified. Intragenic heterozygozity was retained in codon 418 of the menin gene in both patients. No mutation was identified in the coding exons of the menin gene. Complete DNA sequencing yielded no hint that defects of the MEN-I gene are responsible for the formation of adrenal myelolipomas. Adrenal myelolipomas do not share the loss of heterozygozity on chromosome 11q13 observed in some benign adenomatous and many malignant adrenocortical tumors.

Sequence analysis of the MEN I gene in two patients with multiple cutaneous lipomas and endocrine tumors

The discovery of mutations of the menin gene in a few multiple endocrine neoplasma type 1 (MEN I)-associated lipomas and loss of heterozygosity (LOH) on chromosome 11q13 in some sporadic lipomas has stimulated the hypothesis that lipomas may belong to the group of sporadic tumors caused by defects of the gene responsible for MEN I. Since it is unclear if the above hypothesis applies to all patients with lipoma or just to specific subsets, we searched to enlarge the database on this topic. For this purpose, we identified two patients with multiple cutaneous lipomas. One had an additional pituitary adenoma and familial presentation of multiple lipomas, the other had recurrent goiter in the setting of a family history of adenomatous goiter. Deoxyribonucleic acid (DNA) was analyzed by complete direct DNA sequencing of all coding exons and splice junctions of the MEN I gene. No mutation was identified in the coding exons of the menin gene. In contrast to former data on sporadic lipomas, these data are the first to render evidence that mutations of the MEN I gene may not be responsible for the formation of multiple lipomas, even if they appear in the context of other endocrine tumors.

Complete sequencing and messenger ribonucleic acid expression analysis of the MEN I gene in adrenal cancer

Adrenal cancer is a rare sporadic disease that has also been observed in the context of multiple endocrine neoplasia type I (MEN I). Adrenal lesions occur in up to 40% of MEN I patients. Loss of heterozygosity of the 11q13 band harboring the menin gene has been reported in more than 50% of patients with adrenal cancer. Despite this high index of suspicion, former screening studies did not reveal mutations of the MEN I gene in 28 patients. We identified loss of heterozygosity of 11q13 microsatellites in five of five patients (100%). In 40%, heterozygosity was retained in codon 418 of the MEN I gene. Complete direct DNA sequencing data of the entire coding region and adjacent splice sites of the MEN I gene were obtained in 14 patients with sporadic adrenal cancer. In only one of them a heterozygous missense mutation, R176Q (exon 3), was identified. Due to the heterozygous pattern and unknown biological effect of this mutation, it is not clear whether there is a causal relationship with adrenal cancer. The total mutation frequency in sporadic adrenal cancer is 1 of 14 (7%). Menin messenger RNA expression was identified in 14 of 14 patients (100%). Transcriptional inactivation of the menin gene is, hence, unlikely to cause loss of its tumor suppressor function in adrenal cancer. Furthermore, we examined three patients who presented adrenal cancer in the context of sporadic multiglandular endocrine tumor disease previously diagnosed on clinical grounds to be MEN I syndrome. An opal stop codon mutation was identified in codon 126 (exon 2) in the adrenal cancer of one of these patients. Formation of the adrenal cancer in this patient may be rather coincidental because the mutation was present in a heterozygous pattern. There was no mutation of the menin gene in the two other patients. This may mean that formation of adrenal cancer in the context of multiglandular endocrine disease denotes an entity different from MEN I in some patients.

MEN I gene mutations in sporadic adrenal adenomas

Loss of heterozygosity (LOH) on chromosome 11q13 occurs in about 20% of sporadic adrenal neoplasms. Adrenal lesions, mostly benign, occur in up to 40% of patients from MEN I kindreds. The MEN I gene, positioned on 11q13, has been considered a primary candidate gene in these lesions. We studied a group of 15 patients with sporadic adrenal adenoma, and 1 patient with multinodular hyperplasia. Of the 16 patients, 4 had incidentally discovered masses, 5 had Conn's syndrome, 6 suffered from Cushing's syndrome, and 9 had high sex hormone production. Studies with the markers D11S480, PYGM, D11S449, and D11S987 in 13 patients (12 of whom were from our group of 16) revealed 4 losses of heterozygosity on D11 S480 on 11q13, but the deletion did not affect the MEN I gene in any case. We present complete direct DNA sequencing data of the menin gene in 14 sporadic adrenal adenomas and one with adrenal hyperplasia. We identified one heterozygous missense mutation, T552S, in a hormonally inactive adrenal adenoma. One base exchange was identified close to the intron-exon boundary in intron 9 of a nodular adrenal hyperplasia. mRNA expression studies found that MEN I was transcribed in all 13 samples analyzed. In summary, our study identified the second patient with sporadic benign adrenal tumor presenting a menin gene mutation. Our complete direct sequencing approach adds evidence that menin gene mutations may account only for a minority of benign adrenal tumors if at all. Another tumor-suppressor gene inactivated in sporadic adrenal neoplasms may be located on chromosome 11q13.

[Medico-legal aspects of thyroid surgery]

The frequency of medico-legal issues after surgery is rising. Knowledge of the character and frequency of such problems following surgery of the thyroid gland is scant. Analysis of 21,515 cases of adverse effects after medical treatment from 1975 through 1998 identified 222 cases (1 %) of litigation following surgery for thyroid diseases. The frequency of litigation problems rose exponentially during this interval. Malpractice was confirmed in 36 cases (16 %). The litigation was directed against the surgeon in 95 % of cases, the anesthesiologist in 2 %, both of them in 3 % and the ear-nose-throat surgeon in one case. Eighty-nine percent of the 222 cases occurred after routine thyroid surgery. Typical complications such as recurrent nerve palsy (50 %), hypoparathyroidism (14 %), bleeding (3 %), and late goiter recurrence (1 %) accounted for 63 % of the presumed but for only 31 % of ascertained malpractice cases. Atypical complications such as other neurologic deficits (10 %), infections (5 %), residual nodules (4 %), scar problems (5 %) accounted for 37 % of the suspected but for 70 % of confirmed malpractice cases. Deficiencies in obtaining informed consent were present in only 11 %. Malpractice was more frequently judged to be present, if a second operation was necessary (P < 0.001), if the goal of the operation had been missed (P < 0.001), or if any kind of complication was followed by a fault in postoperative care (P < 0. 001).

Modulation of intestinal epithelial wound healing in vitro and in vivo by lysophosphatidic acid

BACKGROUND & AIMS

Lysophosphatidic acid (LPA) is assumed to play an important role in the modulation of injury and tissue repair in nonepithelial tissues. The effects of LPA on intestinal epithelial wound repair in vitro and in vivo were characterized.

METHODS

Effects of LPA on intestinal epithelial restitution and proliferation were assessed by using an in vitro wounding model with confluent intestinal epithelial cell line 6 (IEC-6) monolayers and colorimetric thiazolyl blue (MTT) assays. In addition, LPA signaling pathways were characterized. Effects of LPA on intestinal wound healing in vivo were studied by using the trinitrobenzene model of colitis in rats.

RESULTS

LPA significantly enhanced migration and inhibited cell proliferation of IEC-6 cells in vitro. The effects on intestinal epithelial cell migration and proliferation were mediated through transforming growth factor beta (TGF-beta)-independent pathways and binding to a G-protein receptor. In addition, LPA significantly ameliorated intestinal epithelial injury in the trinitrobenzene model of colitis in rats.

CONCLUSIONS

These findings suggest that LPA enhances intestinal epithelial wound healing by modulation of intestinal epithelial cell migration and proliferation through TGF-beta-independent pathways. Thus, exogenous administration of LPA may provide a new approach for modulating intestinal injury in vivo.

Regulation of the HGF-receptor c-met in the thyroid gland

HGF (hepatocyte growth factor) has been characterised as an important mitogen and motogen in many epithelial cells. The biological and clinical significance of HGF and its receptor c-met in the thyroid is currently under study. Overexpression of c-met is an important feature of papillary thyroid cancer. We developed a quantitative differential RT-PCR method in order to examine HGF-receptor regulation using RNA of about 50 cells per analysis. Experiments were performed in three spontaneously transformed follicular thyroid cancer (FTC) cell lines FTC-133, 236, and 238, 7 primary cultures derived from multinodular goitres, one from Graves disease and 1 from papillary thyroid cancer (PTC). TGF-alpha and to a minor degree HGF were shown to induce a marked up-regulation of the receptor whereas bovine TSH, NaI, dbcAMP or basic FGF had no apparent effect. We conclude that expression of the HGF-receptor is under control of paracrine growth factors activating tyrosine-kinase-dependent pathways. We could demonstrate a minor stimulation of thyroid cell proliferation by HGF in presence but not in absence of 10% fetal calf serum.

Rare loss of heterozygosity of the MTS1 and MTS2 tumor suppressor genes in differentiated human thyroid cancer

Loss of heterozygosity (LOH) of the MTS1 (p16) tumor suppressor gene has been reported to occur frequently in thyroid cancer cell lines. In order to determine the frequency of LOH for these multiple tumor suppressor genes, we used microsatellite markers IFNA and D9S171 to perform differential quantitative polymerase chain reaction. Tumor DNA was isolated from native sections of tumor tissue. Control DNA was isolated from blood. PCR products were separated on 6% polyacrylamide sequencing gels and quantified according to peak height and area. Analysis was informative in 70% of cases for both markers, and in 88% for at least one out of both. LOH was found in 3 out of 35 informative patients (8.6%) with papillary thyroid cancer, in 1 out of 7 patients with follicular thyroid cancer (14.2%), and in 0 out of 18 medullary cancers (0%). No LOH was found in 11 informative patients with multinodular goitre, 7 with follicular adenoma, 4 with Graves' disease, and 6 with other thyroid disease. 75% of LOH was found in T1 and T2 stages, it was not more frequent in patients with lymphonodular metastasis. The low frequency of LOH in these types of thyroid cancer argues against a role of loss of heterozygosity at the MTS 1 and 2 gene locus in the development of differentiated thyroid neoplasia.

[Geographical differences of thyroid carcinoma and basic molecular principles]

Geographical differences have been demonstrated for the cancer incidence and histology of differentiated thyroid cancer. Iodine intake and specific external noxes, such as nitrosamine ingestion or external radiation are important factors. It is still questionable whether histologically identical differentiated thyroid cancers are prognostically different in low and rich iodine areas. Despite increased knowledge of molecular and genetic changes in differentiated cancer, the present therapy is primarily related to patient age, tumor stage and histology.

[Prophylaxis of cytomegalovirus infections with ganciclovir in kidney transplant recipients]

In an open-labeled randomized study, prophylactic treatment with ganciclovir (day 15 to day 29) was administered to 23 cytomegalovirus seronegative patients who received a kidney from a cytomegalovirus seropositive donor. Both groups (control = 11, ganciclovir = 12) were similar in age, immunosuppressive treatments, acute rejection episodes and number of steroid pulses. A seroconversion occurred in 10 control patients (91 percent) and in 10 patients of the ganciclovir group (84 percent). A cytomegalovirus disease was observed in 10 control patients (91 percent) and in 8 patients of the ganciclovir group (66 percent). The delay between grafting and cytomegalovirus disease was significantly longer in the ganciclovir than in the control group (78.5 +/- 7.7 vs 46.5 +/- 5.5 days, P < 0.05). In conclusion, in renal transplant recipients who are at high risk of cytomegalovirus disease, prophylactic treatment with ganciclovir delays the onset of the disease and seems to decrease slightly its frequency.