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91.
Carcinoid tumor of the pancreas is extremely rare. This article describes the case of a 22-year-old woman who manifested a typical carcinoid syndrome; a definitive diagnosis of a metastatic carcinoid tumor was made from needle aspiration of a supraclavicular lymph node using morphologic, immunocytochemical, and ultrastructural criteria. The carcinoid tumor was subsequently shown to be of pancreatic origin.  相似文献   
92.
The fine needle aspiration cytology of two cases of bronchiolo-alveolar cell carcinoma of the lung having unusual features is reported. One case demonstrated numerous psammoma bodies in the cytologic smears, whereas the other case showed an abundance of cells with optically clear nuclei. Both peripherally located tumors were resected and confirmed as primary bronchiolo-alveolar cell carcinoma by histologic and ultrastructural examination. We believe this to be the first report describing these unusual features of bronchiolo-alveolar cell carcinoma diagnosed by fine needle aspiration cytology. Presented is a discussion of psammoma bodies and optically clear nuclei seen in primary and metastatic tumors of the lung. This will aid in the diagnosis of these cases.  相似文献   
93.
Amyloid fat pad aspiration specimens for cases with a clinical suspicion of amyloid typically are stained with Congo red and examined by brightfield microscopy. Congophilia with apple-green birefringence by polarization microscopy (PM) is considered diagnostic for amyloid. Examination of Congo red-stained slides by fluorescent microscopy (FM) is considered by some to be a more sensitive detection method. In this study, we assessed the utility of this technique in cytopathology archival slides from abdominal fat pad aspirations previously stained with Congo red dye. Seventy-eight cases of abdominal fat pad aspirations collected during the last 5 yr and stained with the Congo red procedure were obtained from archival files. Additionally, 20 adipose tissue material slides prepared from the surgical pathology specimens were examined as controls. One representative smear was examined in each case using FM equipped with rhodamine excitation/absorption (540/570 nm) filters. Relevant clinical information was obtained in all cases. Twelve cases (15.4%) of the 78 fat pad aspiration cases were reported originally as positive by Congo red stain using polarization and apple-green birefringence as diagnostic criteria. On review, four cases were deemed unsatisfactory. By FM examination 29 of the 74 (39.2%) cases were reclassified as positive for amyloid. The results were confirmed by immunohistochemical stain for amyloid P protein and electron microscopy. A number of similar distinct fluorescence and immunohistochemical patterns were recognized in the positive cases. Minimally weak fluorescence in the adipose tissue was observed in the control cases. The use of FM in Congo red-stained fat pad smears can improve the detection of amyloid in cytology preparations.  相似文献   
94.
We report three cases of well-differentiated neuroendocrine carcinoma originating primarily in the anterior mediastinum which had been initially investigated by fine-needle aspiration cytology in conjunction with immunocytochemistry and subsequently recognized as thymic in origin. Aspirates consisted of loosely cohesive or aggregated medium sized elements with round to oval nuclei and scanty cytoplasm. in all cases the Romanowsky stain provided an excellent delineation of definite paranuclear inclusion-like structures having a semicircular or discoid appearance which appeared to contain cytokeratin by immunocytochemical studies and were very similar to the intermediate filament paranuclear “buttons” found in neuroendocrine Merkel cell carcinoma of the skin. This appears to be a novel cytologic observation for thymic neuroendocrine carcinoma. We discuss the significance of the above cytologic and immunocytochemical findings and their possible role in the diagnosis of thymic neuroendocrine carcinoma by fine-needle aspiration biopsy. © 1995 Wiley- Liss, Inc.  相似文献   
95.
BackgroundTo diagnose periprosthetic joint infection (PJI) preoperatively, ultrasound-guided joint aspiration (US-JA) may not be performed when effusion is minimal or absent. We aimed to report and investigate the diagnostic performance of ultrasound-guided periprosthetic biopsy (US-PB) of synovial tissue to obtain joint samples in patients without fluid around the implants.MethodsOne-hundred nine patients (55 men; mean age: 68 ± 13 years) with failed total hip arthroplasty (THA) who underwent revision surgery performed preoperative US-JA or US-PB to rule out PJI.ResultsSixty-nine of 109 patients had joint effusion and underwent US-JA, while the remaining 40 with dry joint required US-PB. Thirty-five of 109 patients (32.1%) had PJI, while 74/109 (67.9%) had aseptic THA failure. No immediate complications were observed in both groups. Technical success of US-PB was 100%, as the procedure was carried on as planned in all cases. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of US-JA were 52.2%, 97.8%, 92.3%, 80.3%, and 82.6%, while for US-PB, they were 41.7%, 100%, 100%, 80%, and 82.5%, respectively, with no significant difference (P = .779). Using the final diagnosis as reference standard, we observed a moderate agreement with both US-JA (k = 0.56) and US-PB (k = 0.50).ConclusionWe present a novel US-guided technique to biopsy periprosthetic synovial tissue of failed THA to rule out PJI. We found similar diagnostic performance as compared with traditional US-JA. This supports future larger studies on this procedure that might be applied in patients without joint effusion.  相似文献   
96.
Pancreatic solid pseudopapillary neoplasm (SPN) is a rare low grade malignant tumour. Distinguishing this entity from other pancreatic neoplasms is critical for therapeutic decision making and prognostication. It predominantly affects young female patients <40 years of age, with excellent clinical outcome following surgical removal. The gold standard diagnostic test is cytopathological or histopathological assessment of fine needle aspirate. There are two main difficulties with this. First, SPN can present with morphological and immunohistochemical appearances that can closely mimic other pancreatic tumours, in particular, pancreatic neuroendocrine tumour (NET). Second, the amount of diagnostic material from fine needle aspiration can be limited. Here, we present a cytopathological case with both challenges during the pre-operative investigation of SPN. The case exemplifies the importance of combining morphological features with a targeted panel of immunohistochemistry to arrive at the diagnosis.  相似文献   
97.
Paraspinal masses (PSM) are uncommon and present a wide spectrum of differential diagnoses on fine-needle aspiration (FNA). We analyzed 59 cases of PSM on FNA in a 15-yr period, in the context of clinicoradiologic correlation. Radiologic findings, clinical data, and tissue biopsies were reviewed. Patients were 14-83 yr of age (mean 54.7) with a M:F ratio of 1.36:1. Of the 59 cases, 39 (66%) were deemed diagnostic. Of these, 8 (21%) revealed nonneoplastic lesions and 31 (79%) yielded neoplasms: 2 (6%) benign and 29 (94%) malignant. Of the malignant cases, 22 (76%) were metastatic tumors from various sites, while 7 (24%) were cancers from local spread, which included non-Hodgkin's lymphoma (NHL, 5) and myeloma (2). Benign neoplasms were nerve sheath tumors. Metastatic tumors consisted of adenocarcinoma, 9; squamous-cell carcinoma, 3; renal-cell carcinoma, 1; and non-small-cell carcinoma/not otherwise specified (NOS), 9. Twenty-four (41%) cases received further studies: immunoperoxidase (IPOX) alone, 17 (71%); special stains for microorganisms, 2 (8%); IPOX/other special stains, 4 (17%); and flow cytometry analysis, 1 (4%). Eight (14%) cases received follow-up biopsies. Half of these biopsies added information to previously "nondiagnostic" FNAs. Of the previously "diagnostic" FNAs, tissue biopsy yielded no additional information. Cytopathologic diagnoses were consistent with the pre-FNA radiology analyses in 13 (39%) cases. In instances of radiologic and cytopathologic discrepancy (4 cases, 12%), diagnoses made by FNA reversed the initial radiologic impression of neoplasm to infection, and vice versa. PSMs are rare lesions (0.26% of total FNAs done in 15 yr at our institution). The most common lesion encountered is metastatic adenocarcinoma, followed by NHL. Ancillary studies are helpful in difficult cases. In cases of radiologic/cytopathologic discrepancy, FNA diagnoses are more accurate and decisive for patient management. The sensitivity and specificity of a PSM FNA are 88% and 75% respectively.  相似文献   
98.
目的:探讨剪切波弹性成像(shear wave elastography,SWE)与细针穿刺洗脱液甲状腺球蛋白(fine-needle aspiration washout thyroglobulin,FNA-Tg)对甲状腺乳头状癌侧颈部淋巴结转移的诊断价值。方法:回顾性分析159例经病理证实为甲状腺乳头状癌(papillary thyroid carcinoma,PTC)的患者资料,对颈部211枚可疑淋巴结进行常规超声、SWE参数平均值(Emean)、FNA-Tg检查,以术后病理结果为金标准,比较各检测方法的诊断效能。结果:(1)SWE Emean转移组[(50.96±27.66) kPa]高于非转移组[(32.20±17.34) kPa],差异有统计学意义(t=8.761,P<0.01)。受试者工作特征(receiver operating characteristic,ROC)曲线分析表明,SWE Emean最佳诊断阈值为40.42 kPa时对PTC颈部淋巴结转移预测价值较高,曲线下面积(area under...  相似文献   
99.
Is there an abnormal fasting duodenogastric reflux in nonulcer dyspepsia?   总被引:2,自引:0,他引:2  
A quantitatively and/or qualitatively abnormal duodenogastric reflux (DGR) could be involved in the pathogenesis of nonulcer dyspepsia (NUD). The aims of this prospective study were to look for (1) a pathological DGR profile during fasting and (2) an eventual correlation between DGR profile and clinical symptoms. Twenty-six NUD patients were investigated. Seven other operated patients with a surgical procedure facilitating DGR episodes and 27 healthy volunteers served as control groups. A clinical score was determined for each patient from a standardized questionnaire. Gastric aspiration was performed for 6 hr in fasting subjects. The aspirates were pooled into 17 samples. In each sample the concentration and the output of total bile acids was determined. If the concentration was larger than 30 mol/liter in pooled samples, the concentrations of free bile acids and the distribution of the conjugated bile acids was determined. The percentage of aliquots with a total bile acid concentration larger than 50 mol/liter (without upper limit), and the percentage with a concentration larger than 2500 mol/liter was also obtained. No significant difference was demonstrated between the healthy volunteers and NUD patients, whatever the parameter considered. However, there was a significant increase in each of the quantitative parameters for the group of operated patients in comparison with the NUD patient group. No significant correlation was found between the clinical score and the DGR profile in NUD patients. Apparently, DGR episodes do not play a primary role in the pathogenesis of NUD.Part of this work was presented at the 4th European Symposium on Gastrointestinal Motility, Krakow, Poland. September 22–24, 1988.Hepatogastroenterology, 35:178, 1988 (abstract).  相似文献   
100.
目的:探索新生儿窒息并发胎粪吸入综合征(meconium aspiration syndrome,MAS)时肾血流动力学的改变。方法:应用彩色超声血流显像技术,对窒息合并MAS的新生儿的肾动脉血流参数及心输出量进行检测。结果:并发MAS的窒息儿肾动脉血流速度和血流量降低,但阻力无改变;心输出量降低;肾血流量与心输出量的比值也降低。结论:并发MAS的窒息儿,其肾脏损害加重,早期检测肾血流动力学变化,早期发现肾功改变并指导治疗。  相似文献   
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