Biomedical subjects
Publications and source records attributed to C Proye.
The paper gives a summary of the intraoperative findings in 38 patients who underwent a reoperation for persistent or recurrent primary hyperparathyroidism. The reasons for failure of the first intervention were inexperience of the surgeon, ectopic and supernumerary glands, parathyreomatosis and true recurrence. Careful localization studies are mandatory in the preoperative work-up of these patients.
INTRODUCTION: HPLC plasma methoxyamines measurements are the updated technique for the diagnosis of adrenergic hypersecretion. Their reliability meets that of urinary measurements. Significance of increased values is not yet fully established for the etiological diagnosis of hypertension in some situations, especially in case of renal insufficiency and in the peri-operative period. The aim of this study is to define the "normal" range of the values of plasma methoxyamines in both of those conditions. PATIENTS AND METHODS: in a General and Endocrine Surgical Unit, 3 homogeneous group of 20 patients each have been studied: group 1, control (patients awaiting thyroidectomy); group 2, patients on maintenance hemodialysis submitted for hyperparathyroidism; group 3, patients submitted to digestive surgery. Measurements were done pre-operatively in group 1, pre and post-operatively in group 2, and post-operatively in group 3. RESULTS: in comparison to the control (11.8 nmol/l), we observed in group 2 a 18 fold increase preoperatively, and a 29 fold increase at post-operative day 1. In group 3, we observed a 2.3, 2.7 and 2 fold increase at post-operative days 1,2 and 3 respectively. All those results were statistically significant. CONCLUSION: Results of measurements of plama methoxyamines should always be matched to the serum creatinine levels. They are meaningful for the diagnosis of endocrine origin of hypertension only late after the early post-operative period.
Evaluation of the malignant potential of phaeochromocytomas in the absence of metastases presents a formidable challenge to both clinicians and pathologists. Until now, no widely accepted clinical, histological, immunohistochemical or molecular method has become available to discriminate malignant from benign phaeochromocytomas. In other endocrine tumours, estimation of proliferative activity by MIB-1 immunostaining has emerged as a promising approach for the determination of metastatic potential. In this study, the utility of MIB-1 immunostaining as a predictive marker for the occurrence of metastases in phaeochromocytomas was evaluated. In addition, the density of S100-positive sustentacular cells was studied, since their depletion has been identified as a negative predictive marker in smaller series. Furthermore, several clinicopathological parameters were evaluated. One hundred and ten patients operated on for a total of 99 benign and 37 malignant phaeochromocytomas were studied. All malignant tumours had documented metastases. The histopathological diagnosis of primary tumours and metastases was reviewed and graded for angioinvasion, capsular extension, and intra-tumoural necrosis. The proliferative index (percentage of MIB-1-positive cells) and the density of S100-positive cells were assessed. In addition, age at resection, associated familial tumour syndromes, tumour size, and tumour location were recorded. Univariate analysis revealed statistically significant correlations between malignancy and proliferative index (p<0.0005) and depletion of S100-positive sustentacular cells (p<0.0005). Fifty per cent of the malignant, but none of the benign phaeochromocytomas had a proliferative index greater than 2.5%. Higher age at resection (p=0. 03), sporadic occurrence (p<0.0005), extra-adrenal location (p<0. 0005), tumour size (p<0.0005), and necrosis (p=0.03) were also significantly associated with malignancy. Logistic regression showed that proliferative index (p=0.0072), size (p=0.0022), and extra-adrenal location (p=0.0012) of the primary tumour were independently predictive for malignancy. In conclusion, this study indicates that assessing the proliferative activity of phaeochromocytomas by MIB-1 immunohistochemistry can predict the occurrence of metastases. The predictive value of S100 immunostaining, tumour size, and extra-adrenal location of the tumour was also confirmed.
What is the future of thyroid surgery in the new millennium? How can surgeons keep abreast of advances in thyroid endocrinology, genetics, surgical therapy, and other aspects of thyroid disease management? How should surgeons be trained to become highly competent in thyroid disease and to perform safe, effective thyroid operative procedures? Nine internationally recognized endocrine surgeons were asked to express their views on these and related subjects. They noted that advances in molecular biology, pathology, and genetics of thyroid disease should allow more tailored surgical approaches during the twenty-first century. Current training of general surgical residents in thyroid and other types of endocrine surgery is highly variable, which may contribute to increased complication rates and number of second operations. The leadership for addressing these deficiencies and promoting a more organized approach to thyroid disease management should come from national endocrine surgery associations and their leaders. It is incumbent upon endocrine surgeons to maintain their central role in the management of many aspects of thyroid disease. Organizing teams of specialists into thyroid centers (centers of excellence) can (1) increase efficiency; (2) increase quality of care; (3) decrease costs; (4) encourage a more individualized approach to surgery; (5) lower complication rates; and (6) foster innovation in technology and disease management. Two years of additional fellowship training in thyroid and endocrine surgery is now being advocated by increasing numbers of national endocrine surgical associations as the best way to prepare surgeons for society's needs for highly skilled, competent thyroid surgeons of the future.
STUDY AIM: The aim of this retrospective study conducted by the "Groupe d'étude des néoplasies endocriniennes multiples type 1" (GENEM) was to report a series of insulinomas associated with multiple endocrine neoplasias type 1 (NEM 1) and to determine the most appropriate strategy for the topographical exploration and surgical management. PATIENTS AND METHODS: From 1960 to 1996, 44 patients were included, 16 men and 28 women (mean age: 36.4 +/- 13.9 years). This study concerned morphological investigations, tumoral features, modalities and results of the treatment. RESULTS: Insulinomas were associated with other functional islet tumors in 15 patients: ZE syndrome (n = 8), glucagonoma (n = 6), vipoma (n = 1). Malignant lesions were present in 6 patients: isolated insulinomas (n = 2), insulinomas associated with ZE syndrome (n = 2) and vipoma (n = 1). The sensitivity of the preoperative imaging procedures was less than 70%. Fourty-one patients were operated on: subtotal pancreatectomy (n = 26 including cephalic enucleations in 8), enucleations (n = 8), total pancreatectomy (n = 3), pancreaticoduodenectomy with caudal enucleations (n = 1), and for 3 patients, no details were available. There was no postoperative mortality. Hyperinsulinism disappeared in 27 patients (including 2 after reoperation) with a mean follow-up of 9 years. Among 6 patients with malignant lesions, 3 were alive with a 3, 4 and 10 year-follow-up. CONCLUSION: Subtotal pancreatectomy with splenic conservation and enucleation of cephalic lesions is suggested as the procedure of choice in this group of patients. This procedure allows simplification of preoperative imaging investigations because lesions of the pancreatic head have only to be detected. Preoperative endoscopic ultrasonography and intraoperative ultrasonography are the best investigations.
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OBJECTIVES: To evaluate the incidence of cardiac deaths following noncardiac nonvascular surgery. STUDY DESIGN: Retrospective survey. PATIENTS: All patients undergoing mainly endocrinous and digestive surgery in a University department of general surgery between 1991 and 1996. METHODS: Analysis of all deaths occurring intra- and postoperatively, until discharge of the patients. Demographic and medical data, including patent myocardial ischaemia and risk factors for coronary artery disease, were recorded and compared with a control group including all patients undergoing surgery from January to September 1996. RESULTS: In the 8,700 patients who underwent mainly endocrine neck surgery (66%), or intra-abdominal surgery (31%), the mortality rate (n = 96) was 1.1% (95% confidence interval [95% CI] = 0.9-1.3%). Patent myocardial ischaemia or high risk factors for coronary artery disease were existing in 24% of patients with neck surgery, 31% of those with intra-abdominal surgery, and in 60% of the deceased patients (P < 0.01 vs control group). Those who died were older, were in a higher ASA physical class, and had undergone an emergency procedure more often than patients of the control group (P < 0.002 for each parameter). Two cardiac deaths, in patients with a patent cardiopathy, were recorded (cardiac mortality: 0.02%; 95% CI = 0.003-0.08%). The main cause of death was infection (n = 46), followed by haemorrhage (n = 12). Seven deaths remained unexplained. CONCLUSION: This study suggests that cardiac morbidity is a rare cause of death after noncardiac nonvascular surgery.
Medullary thyroid carcinoma (MTC) is a calcitonin (CT)-secreting endocrine tumor. Although plasma CT level is a specific and sensitive marker of MTC, its preoperative usefulness in predicting tumor size and postoperative CT normalization has not been documented. From a nationwide database set up by the French CT Tumor Study Group, 226 MTC patients were selected according to the following criteria: preoperative CT level determination by an immunoradiometric assay (normal value, < 10 pg/mL) within the 6 months prior to surgery, total thyroidectomy and diagnosis of MTC ascertained by histological report including tumor size. Patients were 129 females and 97 males (female/male ratio, 1.3). One hundred and twelve patients (49.6%) had the sporadic variety of the disease, 74 (32.7%) had multiple endocrine neoplasia 2A, three (1.3%) had multiple endocrine neoplasia 2B, and 37 (16.4%) had familial MTC. Median age at diagnosis was 44.8 yr (range, 4.9-80.1 yr). Complete neck dissection was performed in 159 patients (70.4%). Postoperative CT normalization was ascertained by negative response of CT to pentagastrin stimulation (< 10 pg/mL) in 94 patients. Seventy-one patients were considered as not cured because of residual tumor tissue and/or elevated CT levels. Median tumor size was 11.0 mm (range, 0.2-80.0 mm), significantly larger in females (15.0 vs. 8.0 mm, P < 0.05), and in sporadic forms (15.0 vs. 7.0 mm, P < 0.05). Tumor size was significantly correlated (r2 = 0.52, P < 0.01) with preoperative CT levels, the relationship being more straight in familial (r2 = 0.71) than in sporadic (r2 = 0.36) forms. Furthermore, preoperative CT levels under 50 pg/mL appeared to be predictive of postoperative CT normalization (44 of 45 patients). However, higher CT levels did not mean absence of postoperative CT normalization (50 of 120 patients). We conclude that low preoperative CT levels are predictive of tumor size and postoperative CT normalization.
Human pancreatic cells with a typical ductal phenotype and potential to proliferate can be obtained in vitro, but the differentiation capacity of these putative human pancreatic stem cells remains to be documented. We investigated the protein and mRNA expression of insulin promoter factor 1 (IPF-1) (or pancreas/duodenal homeobox 1), a transcription factor critical for pancreatic development and endocrine cell neogenesis, in human pancreatic ductal cells derived from cultured exocrine tissue. In vitro, exocrine cells rapidly adhered (within 12 h) and were de-/transdifferentiated to ductal cells after 3 days with a dramatic loss of amylase protein (n = 4, 92 +/- 3.3%, P < 0.05 vs. day 1) and a simultaneous increase of ductal cytokeratin 19 protein (n = 4, 3.4-fold on day 3 and 7-fold on day 9, P < 0.05 vs. day 1). IPF-1 protein and mRNA levels were low to undetectable in exocrine preparations before culture. After 2 days of culture, a 3.2-fold increase in IPF-1 protein was observed, corresponding to the characteristic 46-kDa protein in Western blots. Reverse transcriptase-polymerase chain reaction confirmed a 10.5-fold increase in IPF-1 mRNA levels after 3 days of culture (n = 5, P < 0.001 vs. day 1). Double immunocytochemistry showed direct evidence that IPF-1 appeared during culture in these exocrine-derived ductal cells (cytokeratin 7-positive) and was not merely in contaminating endocrine cells (chromogranin A-positive). In conclusion, we describe herein the first converging evidence on both the molecular and protein level that human cells with a typical ductal phenotype derived ex vivo from pancreatic exocrine tissue (obtained from healthy donors) can reexpress IPF-1 in culture, suggesting their pancreatic precursor/stem cell potential.
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Cell therapy offers today important perspectives for the treatment of type 1 diabetes. The current utilization of primary human islets of Langerhans nevertheless forbids all hope of developing this treatment on a large scale. The recent description of the persistence of stem cells capable of proliferating and differentiating in the adult pancreas offers an attractive alternative for the production in vitro of homologous insulin-secreting cells. We first reproduced in vitro from human islet preparations the proliferation of ductal epithelial structures and their progressive organization. Thereafter, we focused on the description of a reproducible source of human ductal cells by the transdifferentiation of exocrine preparations. More recently we described in these exocrine derived ductal cells the the expression the of insulin promoter factor-1 (IPF-1/otherwise known as PDX-1), a transcription factor essential for the differentiation of ductal cells into endocrine cells during both development and pancreatic regeneration. If the proliferation and differentiation of these cells is confirmed, this approach could lead to the description of an abundant source of human pancreatic stem cells for the production ex vivo of human insulin secreting cells and may even allow autologous cell therapy, in the absence of immunosuppression.
In order to define the role of scintigraphy in determining the aetiology of primary aldosteronism, 41 patients were examined by computed tomography (CT) scan and adrenal scintigraphy using iodine-131 6beta-methyl-iodo-19-norcholesterol with the dexamethasone suppression test. Hormonal and scintigraphic examinations were conducted while avoiding interference by medical treatment. The aetiological diagnosis was established by taking account of the clinical context, the endocrine profile, and CT scan and scintigraphic data, as well as possible hormone assays after catheterization of the adrenal veins (12 cases) and postoperative pathology data (14 cases). The aetiological diagnoses established were Conn's adenoma (insensitive to angiotensin II) in 12 cases, idiopathic hyperplasia in 11 and macronodular hyperplasia (with functional autonomy of the nodules) in 18. Unilateral and bilateral lesions were correctly distinguished by scintigraphy in 92% of cases as compared with only 58% using CT scan alone; this was because the CT scan appearance was normal in 3/12 cases of adenoma and because a single nodule was visible in 2/11 cases of idiopathic hyperplasia and in 12/18 cases of macronodular hyperplasia. It is concluded that scintigraphy using noriodocholesterol with the dexamethasone suppression test should be performed systematically in conjunction with hormonal tests and adrenal CT scan in all cases of primary aldosteronism, as part of a strategy aimed not only at detecting adenoma but also at determining whether the hyperfunctional lesions are bilateral.
STUDY AIM: The aim of this prospective study conducted by the AFCE was to analyze the indications, approach and results of all adrenalectomies performed during the year 1997 in 17 centers, active or specialized in endocrine surgery. PATIENTS AND METHODS: During 1997, adrenalectomy was performed in 247 patients, 149 men and 98 women (mean age: 51 years). The lesion was located in the right side in 166 patients, in the left side in 99, in both sides in 28 patients and ectopic in four patients. Pheochromocytomas (n = 61), Conn adenomas (n = 50) and Cushing syndrome lesions (n = 48) were the most frequent in this series. Laparoscopic adrenalectomy was performed in 172 patients (70%) through a transperitoneal approach in all cases except one, and by 'open' surgery in 75 patients (30%). RESULTS: In patients operated on by the laparoscopic approach, the mean duration of surgery was 132 min, and there were peroperative complications in 15 patients (8.7%), mainly hemorrhages. Conversion rate into laparotomy was 7%. In the postoperative course, there were three reoperations and two deaths, an early one in a patient reoperated for bleeding and a very late one in relation with necrotising acute pancreatitis. Mean duration of hospitalization was 5.8 d. Mean tumoral size was 49 mm. In patients operated on by 'open' surgery, the mean duration of surgery was 148 min. There was a postoperative complication in eight patients (10.6%), mostly hemorrhages, and two intraoperative deaths in relation with uncontrollable bleeding. Mean duration of hospitalization was 11 d. Mean tumoral size was 72 mm. CONCLUSION: Laparoscopic adrenalectomy is now indicated for the majority of adrenal tumors. Several complications observed in this series were related to the learning curve in several centers. Laparoscopic adrenalectomy is the 'gold standard' in uni- or bilateral benign tumors no larger than 6 or 7 cm. 'Open' surgery is indicated in malignant tumors, especially in adreno-cortical carcinomas, and in all large tumors.
BACKGROUND & AIMS: Risk factors of metachronous liver metastases and death are not well known in patients with the Zollinger-Ellison syndrome and multiple endocrine neoplasia type 1. These factors were retrospectively determined in 77 patients. METHODS: Data chart review was performed. RESULTS: Median follow-up was 102 months (range, 12-366). Surgery was performed on 48 patients, including 9 of the 10 patients with large pancreatic tumors (>/=3 cm). Liver metastases developed in 4 patients (40%) with large pancreatic tumors, in 3 (4.8%) without, and in 1 of the 4 patients with pancreatic tumors of unknown size; all had previously undergone surgery. The only independent factor associated with development of liver metastases identified by multivariate analysis was large pancreatic tumors (risk ratio, 29.0; 95% confidence interval [CI], 3. 2-260.7). Surgery was not selected. The probability of being free of liver metastases in the 63 patients without large pancreatic tumors was 96% (95% CI, 88-100) at 10 and 15 years. Thirteen (16.9%) patients died. The only independent factors of death selected by multivariate analysis were Zollinger-Ellison syndrome diagnosis before 1980 (risk ratio, 8.2; 95% CI, 1.7-40.6) and age at diagnosis (risk ratio/year, 1.08; 95% CI, 1.03-1.14). CONCLUSIONS: Large pancreatic tumors are predictive of the development of metachronous liver metastases, and surgery does not seem to prevent them.
OBJECTIVE: Multiple endocrine neoplasia type 1 (MEN1) is an autosomal genetic disorder, the clinical phenotype of which includes tumours of the parathyroids and/or anterior pituitary and/or endocrine pancreas. The genetic defect has been mapped to the chromosome 11q13 and the MEN1 gene has been recently identified, thus allowing genetic screening in affected kindreds. The aim of this study was to establish the usefulness of genetic screening in the follow-up of a large MEN1 kindred. PATIENTS: We describe a large kindred of 91 members, of whom 56 had clinical, biochemical and genetic screening. Twenty eight of them have been tested annually for the last 5 years. RESULTS: Although the precise mutation is still undetermined in this kindred, genotypic determination confirmed linkage with the MEN1 gene in affected members and excluded 28 members from annual testing. By drawing our attention to susceptible subjects, genetic screening improved the evaluation of age-related penetrance of the disease in the 3 generations from this kindred. For instance, annual screening showed conversion from unaffected to affected phenotype in 4 subjects aged 14, 14, 15, and 17 years. Moreover, genetics helped us to evaluate the specificity of clinical or biochemical markers, and thus to discard useless investigations. So far however, the genetics have not helped to explain the phenotypic heterogeneity and particularly low incidence of pancreatic tumours in this kindred. CONCLUSION: Genetic screening is very useful in detecting high risk individuals for MEN 1, since it avoids time-consuming and expensive investigations in non-affected subjects. By providing better understanding of the age-related penetrance of this syndrome, it improves the efficiency of screening. Genetic studies allow differentiation between clinical and biochemical features that are useful in follow-up and other confusing or unhelpful parameters.
BACKGROUND: Despite abundant literature on parathyroid scanning with technetium 99m-labeled cationic complexes, comprehensive clinical reports that unequivocally correlate scanning findings with the anatomy of parathyroid glands in extensive and homogeneous cohorts of patients are lacking. METHODS: We analyzed the records of patients with sporadic primary hyperparathyroidism who had had a preoperative scan with either 99mTc-labeled sestamibi or 99mTc-labeled tetrofosmin at our institution and who were cured after a bilateral surgical neck exploration procedure. RESULTS: In 261 patients, 710 normal and 347 abnormal glands (1494 +/- 2626 mg), including 15 glands within the mediastinum, were identified. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of scanning were 82%, 98%, 91%, 94%, and 94%, respectively, in 197 patients with uniglandular disease and 53%, 98%, 98%, 60%, and 72%, respectively, in 64 patients with multiglandular disease. False-positive uptakes were encountered in 17 patients (7%), 3 false-positive uptakes being within the mediastinum. If the unilateral approach had been followed, guidance with preoperative scanning would have significantly increased the number of effective unilateral neck exploration procedures (164 patients (63%) vs 78 patients (30%); P < .001). One abnormal gland would also have been neglected in 28 patients (11%). CONCLUSIONS: Preoperative scanning would limit neck exploration procedures in two thirds of patients with sporadic primary hyperparathyroidism but may also increase the risk of failure in the most challenging cases.
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