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1.
Syndromes involving peptide or nonsex steroid hormone secretion due to aberrantly located tumors are rare. We report a collected series of 16 patients with ectopic hormone production from ovarian neoplasms, including 3 patients recently encountered at our institution as well as 13 additional cases identified in the recent literature. These tumors included 2 insulin-producing ovarian carcinoids, 1 ACTH-producing pituitary adenoma within a benign ovarian cystic teratoma, 2 cortisol-producing ovarian neoplasms, 8 gastrin-producing ovarian cystadenomata or cystadenocarcinomata, and 3 thyroxine-producing ovarian strumal carcinoids. All patients presented with syndromes of hormone excess. Only 62% of all tumors were localized preoperatively. Following ovarian resection, 87% of patients remained disease-free with a median follow-up period of 1.5 years. In addition to ovariectomy, 8 additional unnecessary ablative procedures were performed in 7 patients. These included distal pancreatectomy, pancreaticoduodenectomy, adrenalectomy, total gastrectomy, selective vagotomy, and subtotal thyroidectomy. Failure to localize the ovarian neoplasm preoperatively was associated with a significantly higher risk of subsequent unnecessary ablative procedures. Because of the potential for the ovary to act as a source of aberrant hormone secretion, we recommend complete preoperative evaluation of the pelvis in female patients presenting with nonlocalizable endocrine tumors.
Resumen Los síndromes relacionados con la secreción de péptidos o de hormonas esteroideas no sexuales por tumores de ubicación aberrante ocurren infrecuentemente. En este artículo reportamos una serie de 16 pacientes con producción hormonal ectópica por neoplasmas ováricos, la cual incluye 3 pacientes vistos recientemente en nuestra institución y 13 identificados en la literatura médica de los últimos años. El grupo incluye 2 carcinoides ováricos productores de insulina, 1 adenoma pituitario productor de ACTH, 2 neoplasmas ováricos productores de cortisol, 8 cistadenomas o cistadenocarcinomas ováricos productores de gastrina, y 3 carcinoides ováricos estrumales productores de tiroxina. Todas las pacientes se presentaron con síndromes de exceso hormonal. En sólo el 62% de los tumores se pudo establecer la ubicación anatómica en la fase preoperatoria. Después de realizada la resección del ovario, 87% de las pacientes permanecieron libres de enfermedad en el período de seguimiento, que fue de 1.5 años en promedio. Además de la resección ovárica, se practicaron otros 8 procedimientos adicionales innecesarios en 7 pacientes. Estos incluyeron pancreatectomía distal, pancreatoduodenectomía, adrenalectomía, gatrectomía total, vagotomía selectiva, y tiroidectomía subtotal. La falla en la localización preoperatoria del neoplasma ovárico apareció asociada con un riesgo aumentado de ulteriores procedimientos quirúrgicos innecesarios. En vista de la potencialidad del ovario de actuar como fuente de secreción hormonal aberrante, nosotros recomendamos una completa evaluación de la pelvis en las pacientes femeninas en quienes se diagnostiquen tumores endocrinos no localizables.

Résumé Les syndromes concernant la sécrétion d'hormones peptidique ou stéroïde nonsexuelle due à des tumeurs ectopiques sont rares. Nous rapportons une série de 16 patientes avec une production d'hormone ectopique provenant de néoplasmes ovariens, comprenant 3 patientes récemment soignées dans notre établissement ainsi que 13 cas supplémentaires relevés dans la littérature récente. Ces tumeurs comprennent 2 tumeurs carcinoïdes ovariennes productrices d'insuline, 1 adénome hypophysaire producteur d'ACTH à l'intérieur d'un tératome cystique ovarien bénin, 2 néoplasmes ovariens producteurs de cortisol, 8 cystadénomes ou cystadénocarcinomes ovariens producteurs de gastrine, et 3 carcinoïdes ovariens strumaux producteurs de thyroxine. Toutes les patientes avaient des syndromes d'hyperproduction hormonale. Soixante-deux pour cent seulement des tumeurs avaient été localisées en préopératoire. Après ovariectomie, 87% des patientes étaient apparamment sans récidive avec un suivi médian d'un an et demi. Cependent, outre l'ovariectomie, 8 interventions supplémentaires non nécessaires ont été accomplis chez 7 patientes. Celles-ci comprenaient: pancréatectomie distale, duodénopancréatectomie, surrénalectomie, gastrectomie totale, vagotomie sélective, et thyroïdectomie subtotale. L'impossibilité de localiser le néoplasme ovarien en période préopératoire était associée à un risque notoirement plus grand de faire une résection inutile. Compte tenu de la possibilité pour l'ovaire de se comporter en producteur de sécrétion ectopique d'hormone, nous recommandons un examen complet préopératoire du bassin chez les femmes se présentant avec des tumeurs endocrines non localisables.


Presented at the International Association of Endocrine Surgeons in Toronto, Ontario, Canada, September, 1989.  相似文献   
2.
How to use Chlamydia antibody testing in subfertility patients   总被引:1,自引:9,他引:1  
Screening for tubal factor subfertility by means of Chlamydia antibody testing (CAT) was introduced into the initial work-up of subfertile couples several years ago. The results reported, however, are heterogeneous, and no uniformity exists in cut-off levels of titres, or in definitions of tubal factor subfertility. We performed a prospective cohort study to evaluate the implications of varying the definitions of tubal pathology and of modifying the cut-off levels on the clinical impact of CAT in predicting tubal factor subfertility. In 227 consecutive patients who attended our fertility clinic, the Chlamydia IgG antibody titre was determined and related to tuboperitoneal abnormalities at laparoscopy as a reference standard. According to received operating characteristic (ROC) curve analysis, a titre of 16 is the optimum cut-off level. Increasing the cut-off level improves specificity and positive likelihood ratio (LR+), at the expense of sensitivity and negative LR (LR-). Changing the definition of tubal factor subfertility from unspecified tuboperitoneal abnormalities into extensive adhesions and/or bilateral distal tubal occlusion improves LR+, LR- and kappa significantly. We conclude that CAT is more accurate in predicting severe distal tubal pathology than unspecified tuboperitoneal abnormalities. Although from a statistical point of view a titre of 16 is the optimum cut-off level, from a clinical point of view 32 or 64 may be preferable, depending on the aim of screening and the inception cohort.   相似文献   
3.
Fluid resuscitation and transfusion therapy are particularly critical in patients undergoing extensive vascular operations because of diffuse atherosclerosis and the risk of perioperative myocardial infarction. Sophisticated perioperative monitoring has reduced the mortality rate substantially, but indications for transfusion remain controversial. We determined erythrocyte volume, (EV), total blood volume (TBV) and plasma volume (PV) preoperatively and 18 to 24 hours postoperatively in 41 elderly patients (68.8 +/- 1.3 years) undergoing elective vascular operations (30 abdominal aortic aneurysmorrhaphy, ten aortofemoral bypass and one carotid endarterectomy). EV was measured using 51chromium-labeled autologous erythrocytes; TBV and PV were calculated from EV and total body hematocrit (peripheral venous hematocrit [HCT] x 0.89). Ideal blood volumes were calculated from nomograms based on body surface area and gender. Relationships between body volumes (percentage of ideal), simultaneously measured peripheral venous HCT and hemodynamic parameters heart rate, mean arterial pressure, central venous pressure, pulmonary capillary wedge pressure, cardiac index and systemic vascular resistance index were studied by stepwise regression. In 24 patients, blood volumes and hemodynamic parameters were also measured in the recovery room. HCT significantly correlated with EV at all three time periods (p less than 0.001), but the ability of HCT to predict EV in an individual patient was relatively poor (r = 0.50 preoperatively; r = 0.54 in recovery room and r = 0.66 24 hour postoperatively). By 24 hours postoperatively, EV had decreased to 78.3 +/- 2.4 percent of ideal EV (range of 47 to 112 percent). However, only two patients had HCT less than 30 despite the fact that 13 of 41 patients had an EV deficit of greater than 30 percent. No patient had a HCT of less than 25 percent. Hemodynamic parameters did not contribute to the prediction of EV, PV or TBV at any time. Two patients had myocardial infarctions postoperatively associated with 24 hour EV deficits of 18.5 and 29.6 percent. One patient died of a pulmonary embolus. Because of these findings, the concept of a "transfusion trigger" must be viewed with caution, since many patients undergoing vascular operations will have considerable EV deficits despite an "acceptable" HCT.  相似文献   
4.
Liver support using extracorporeal devices and hepatocyte transplantation has received renewed interest for the management of acute and chronic liver failure. The aim of this study was to determine whether xenogeneic porcine hepatocytes could integrate into the liver parenchyma of cirrhotic Lewis rats when administered by an intrasplenic route. Cirrhosis was induced by carbon tetrachloride (CCl4) inhalation and confirmed histologically. Freshly isolated porcine hepatocytes were infused directly into the splenic pulp at laparotomy over a 5-15-min interval. Using (111)In-labeled hepatocytes, the degree of localization of porcine hepatocytes to the spleen and liver was found to be greater than 60% in both control and cirrhotic rats. Integration of porcine hepatocytes into the rat liver parenchyma was determined by immunohistochemical staining for porcine albumin in rat liver sections. Further confirmation was provided by in situ hybridization using a porcine-specific probe that binds to a distinct repetitive element (PRE) in porcine DNA. Evidence of integrated porcine hepatocytes was seen for over 50 days in animals under cyclosporine immunosuppression. These data demonstrate the integration of xenogeneic porcine hepatocytes into the liver of the cirrhotic rat and their ability to produce porcine albumin for up to 50 days.  相似文献   
5.
6.
Medicinal plants based traditional systems of medicines are playing important role in providing health care to large section of population, especially in developing countries. Interest in them and utilization of herbal products produced based on them is increasing in developed countries also. To obtain optimum benefit and to understand the way these systems function, it is necessary to have minimum basic level information on their different aspects. Indian Systems of Medicine are among the well known global traditional systems of medicine. In this review, an attempt has been made to provide general information pertaining to different aspects of these systems. This is being done to enable the readers to appreciate the importance of the conceptual basis of these system in evolving the material medica. The aspects covered include information about historical background, conceptual basis, different disciplines studied in the systems, Research and Development aspects, Drug manufacturing aspects and impact of globalization on Ayurveda. In addition, basic information on Siddha and Unani systems has also been provided.  相似文献   
7.
8.
Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy.  相似文献   
9.
At the Department of Radiation Oncology, Westmead Hospital, between 1980 and 2000, 60 patients with squamous cell carcinoma of anal canal or margin (including 15 with Stage IIIA or IIIB) were treated radically; 55 received chemoradiation (89% were prescribed mitomycin C and 5‐fluorouracil). Five‐year overall survival was 64% (95% confidence interval (CI): 48–79%), with a median survival of 9.75 years (median follow up 5.6 years, range 5 months to 22.5 years). Ten patients have died of disease. At 2 years the local control rate was 86%, and colostomy‐free survival was 83%. Relapse after 2 years was uncommon. Tumour size was the main factor driving outcomes, especially survival. Patients with larger tumours (T > 4 cm) had a hazard ratio for survival of 5.7 (95% CI: 1.8–17). Fourteen (24%) patients experienced treatment interruptions as a result of acute toxicity, including one death from neutropoenic sepsis. Seven (12%) patients, in total, experienced one or more late toxicities, grade 3 or above, including four women (all postmenopausal) who developed a radiation‐induced bone injury. Most patients with anal cancer can expect to retain a functional sphincter after chemoradiation/radiation. Further studies are in progress to determine the optimal chemoradiation protocol.  相似文献   
10.
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