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Paraganglioma of the ampulla of Vater: a potentially malignant neoplasm   总被引:4,自引:0,他引:4  
Paragangliomas are rare tumours originating from neuroectodermic remnants and are usually considered as benign. We present two cases of paraganglioma of the ampulla of Vater that were treated surgically by pancreaticoduodenectomy. In one case, histopathology revealed malignant characteristics of the tumour with invasion of the pancreas and simultaneous duodenal lymph-node metastases. Both patients had a favourable outcome without disease recurrence at 40 and 44 months postoperatively. Only 21 cases of ampullary paraganglioma have been reported in the literature, 7 of them with malignant characteristics. In conclusion, paragangliomas of the ampulla of Vater have malignant potential. Surgical therapy of these tumours should not be limited to local resection, as disease recurrence and lymph node involvement have been reported. We propose that paragangliomas of the ampulla of Vater should be operated by cephalic pancreaticoduodenectomy, which allows long-term and disease-free survival.  相似文献   
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PURPOSE: Stercoral perforation of the colon is reported to be a rare disease with poor prognosis. The aim of this study was to determine the frequency of stercoral perforation of the colon, to define diagnostic criteria for stercoral perforation of the colon, and to analyze the patient outcome in a university hospital gastrointestinal surgery unit. METHODS: From November 1993 until November 1998 all surgically treated patients with a colorectal disease were prospectively recorded in a computerized database. Diagnosis of stercoral perforation of the colon was made if 1) the colonic perforation was round or ovoid, exceeded 1 cm in diameter, and lay antimesenteric; 2) fecalomas were present within the colon, protruding through the perforation site or lying within the abdominal cavity; and 3) pressure necrosis or ulcer and chronic inflammatory reaction around the perforation site were present microscopically. Any additional colon pathology led to exclusion from the diagnosis of stercoral perforation of the colon. Using the same criteria, 81 cases in the literature were found to qualify and were further analyzed. RESULTS: In a five-year period 1,295 patients underwent colorectal interventions through laparotomy. A total of 566 (44 percent) cases were emergencies, 220 (17 percent) of these caused by colonic perforation. Seven patients had stercoral perforation of the colon. The incidence of stercoral perforation of the colon was 0.5 percent of all surgical colorectal procedures through laparotomy, 1.2 percent of all emergency colorectal procedures, and 3.2 percent of all colonic perforations. The mean age of the patients was 59 (median, 64; range, 22–85) years. All perforations were situated in the left hemicolon or upper rectum. The round or ovoid perforation had a mean diameter of 3.6 cm. Fecalomas were present in all patients and protruded from the perforation site or were found within the free abdominal cavity in three of them. Generalized stercoral peritonitis was a constant finding. Using a colonic resection without immediate restoration of continuity, an extensive intraoperative lavage, and antibiotics, there was no in-hospital mortality. Analysis of the reports in the literature revealed additionally that 28 percent of patients with stercoral perforation of the colon have multiple stercoral ulcers in the colon and that substantial mortality is encountered if only minor surgical procedures of treatment are used. CONCLUSIONS: The incidence of stercoral perforation of the colon seemed to have been underestimated. The reason for this might be the lack of defined diagnostic criteria for this disease. Low mortality is obtained by early surgical eradication of the affected part of the colon, including all stercoral ulcers, and by aggressive therapy for peritonitis.Presented in part at the meeting of the Swiss Society of Surgery, Lugano, Switzerland, June 9 to 12, 1999.  相似文献   
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BACKGROUND: Transforming growth factor-alpha (TGF-alpha) is a key mediator of colonic mucosal protection and/or repair mechanisms in orally induced acute dextran sodium sulphate (DSS) colitis. However, it also has been suggested that TGF-alpha may contribute to malignant transformation in the colon. The aim of the studies was to determine whether TGF-alpha is needed for malignant transformation in orally induced chronic DSS colitis using TGF-alpha deficient mice (wa-1) and Balb/c mice, a strain competent in TGF-alpha. METHODS: Chronic colitis was induced by oral administration of DSS (5%) for 7 days followed by drinking water for 10 days in wa-1 and Balb/c mice (n = 20, per group). In the two subsequent cycles (7 days DSS, 10 days water) 3% DSS-water was utilized due to a high mortality in the wa-1 group. Mucosal injury severity was assessed histologically and graded (three grades). A crypt damage score (CDS) reflecting all three grades of mucosal pathology was calculated. Mucosal dysplasia and cancerous lesions were noted. RESULTS: Seven per cent of the entire colonic mucosa was completely destroyed in wa-1 animals compared to 3% in Balb/c mice (P < 0.05). The CDS was 10.2 +/- 0.4 and 4.8 +/- 0.3 in wa-1 and Balb/c mice, respectively (P < 0.05). Fifteen incidences of mucosal dysplasia were found in the 10 surviving wa-1 animals and 31 incidences were found in 20 Balb/c animals. In both groups, one fully developed adenomatous cancerous lesion was present. CONCLUSIONS: The markedly increased severity of mucosal injury in chronic induced DSS colitis in TGF-alpha deficient wa-1 mice compared to Balb/c mice further substantiates that endogenous TGF-alpha is a pivotal mediator of protection and/or healing mechanisms in the colon. The appearance of dysplastic and cancerous lesions in TGF-alpha deficient animals suggests that TGF-alpha per se is not essential for malignant mucosal cell transformation in colitis.  相似文献   
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BackgroundKnowledge about causes of sports-related sudden cardiac arrest (SrSCA) may influence national strategies to prevent such events. Therefore, we established a prospective registry on SrSCA to estimate the incidence and in particular describe the etiologies of SrSCA in the general population in Germany.MethodsThe registration of SrSCA based upon 4 pillars: a web-based platform to record SrSCA cases in competitive and recreational athletes, media-monitoring, cooperation with the German Resuscitation Registry, and 15 institutes of forensic medicine.ResultsAfter an observation period of 6 years, a total of 349 cases was recorded (mean age 48.0 ± 12.7 years); 109 subjects survived. Most of the cases occurred during nonelite competitive or recreational sports. Bystander cardiopulmonary resuscitation (CPR) was initiated in 262 cases (75%); however, rhythm analysis and defibrillation (if indicated) was mainly performed by medical services. In patients ≤ 35 years of age, premature coronary artery disease (CAD) and sudden arrhythmic death syndrome (SADS) prevailed, followed by myocarditis. In athletes ≥ 35 years of age, CAD predominated.ConclusionsCountry-specific registries are necessary to define the national screening and prevention strategy optimally. In Germany, premature CAD, SADS, and myocarditis are the leading causes of SrSCA in young athletes, reinforcing the great disparity of the prevalence of cardiac diseases among different countries. Extension of on-site SCD-prevention campaigns, with training of CPR and explanation of the efficient use of automated external defibrillators (AEDs), may decrease the burden of SrSCD.  相似文献   
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