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21.
Epithelial‐myoepithelial carcinoma (EMC) is a rare salivary gland malignancy with variable cytologic findings. Its rarity, variable morphologic findings, and similarities with more common salivary gland entities make it a difficult cytologic diagnosis. As the name signifies, the key feature of this tumor is presence of an epithelial and myoepithelial component. However, when one of these two components is scant on the fine needle aspiration (FNA) smears, it may be overlooked. We present a case from a 62 year‐old female who presented to the clinic with a parotid nodule and episodes of sharp, throbbing pain. A fine needle aspiration was performed which revealed a highly cellular specimen comprised primarily of aggregates of cells with small, round nuclei and scant to absent cytoplasm. Abundant hyaline stromal material was also noted. The case was signed out as basaloid neoplasm with a recommendation for surgical resection. The subsequent resection specimen revealed EMC. By reviewing the FNA specimen following the surgical resection of the tumor, we were able to utilize the benefit of hindsight to more clearly identify the subtle, biphasic components of the tumor. Diagn. Cytopathol. 2016;44:422–425. © 2016 Wiley Periodicals, Inc.  相似文献   
22.
Pancreatic anaplastic carcinoma (PAC) is rare and has an aggressive clinical course. We report an autopsy case of PAC focusing on the cytopathological characteristics of the tumor and immunocytochemical staining for vimentin, E‐cadherin, and zinc finger E‐box binding homeobox 1 (ZEB1), which markers are associated with epithelial markers of epithelial‐mesenchymal transition (EMT). A 50‐year‐old woman presented to our hospital with a chief complaint of jaundice. A pancreatic head tumor and multiple liver nodules were detected on abdominal computed tomography. Biliary cytology under endoscopic retrograde cholangiopancreatography suggested ductal adenocarcinoma. Three months after admission, she died of multiorgan failure. At autopsy, touch imprint cytology using squash preparation of the pancreatic tumor identified two different cell types; numerous isolated malignant cells with large and pleomorphic nuclei and a few clusters showing irregularly overlapped nuclei and irregular contours within the necrotic background. Immunocytochemically, isolated cells were positive for vimentin and ZEB1, and negative for E‐cadherin. Conversely, clusters were negative for vimentin and ZEB1, and positive for E‐cadherin. Histologically, the tumor was composed of sarcomatous cells with small foci of adenocarcinoma, which were consistent with a diagnosis of PAC. Immunohistochemical staining of the adenocarcinoma and sarcomatous cells corresponded to those of the clusters and isolated malignant cells, respectively. Immunostaining of these EMT markers is useful to distinguish sarcomatous cells from adenocarcinoma and can contribute to the accurate diagnosis of pancreatic tumors with EMT.  相似文献   
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Diagnosis of metastatic lesions to the stomach by salvage cytology   总被引:1,自引:0,他引:1  
Summary Secondary neoplasms of the stomach are rare and are often clinical and diagnostic problems. Three patients with bleeding volcano-like ulcers were diagnosed by combined endoscopic salvage cytology and surgical biopsy as having metastatic submucosal lesions from hematologic spread. The combination of endoscopic appearance, clinical findings, and tissue and cytologic examination can lead to the correct diagnosis. The results from these cases support the utility of this cytologic technique in combination with biopsy in this clinical setting.  相似文献   
26.
目的采用心脏MR(CMR)前瞻性研究冠状动脉斑块对心肌缺血的预测价值。方法 52例行冠状动脉造影(CA)后评定为可疑冠心病(CAD)的病人进行了CMR和  相似文献   
27.
Intratemporal vascular tumors: detection with CT and MR imaging   总被引:1,自引:0,他引:1  
The diagnostic contributions of computed tomography (CT) and magnetic resonance (MR) imaging were compared in 12 patients with benign intratemporal vascular tumors (hemangioma or vascular malformation). The tumors included six in the internal acoustic canal and six in the geniculate ganglion region. Clinical and histologic correlations were made. Two of the six patients with tumors in the internal acoustic canal underwent CT, and both required gas cisternography to show the tumor. Five patients in that group underwent MR imaging, and all five studies showed the tumor. All six patients with geniculate ganglion tumors underwent CT. Results in one study were questionable, and five showed the tumor. Five patients in this group underwent MR imaging, but the MR findings were positive in only two cases. MR imaging should therefore be performed before CT in the evaluation of facial nerve dysfunction, as it demonstrated all tumors in the internal acoustic canal and some in the geniculate ganglion region. If MR findings are negative, CT should then be performed to rule out a possible geniculate ganglion lesion.  相似文献   
28.
For selected indications, coronary computed tomographic (CT) angiography is an established clinical technology for evaluation in patients suspected of having or known to have coronary artery disease. In coronary CT angiography, image quality is highly dependent on heart rate, with heart rate reduction to less than 60 beats per minute being important for both image quality and radiation dose reduction, especially when single-source CT scanners are used. β-Blockers are the first-line option for short-term reduction of heart rate prior to coronary CT angiography. In recent years, multiple β-blocker administration protocols with oral and/or intravenous application have been proposed. This review article provides an overview of the indications, efficacy, and safety of β-blockade protocols prior to coronary CT angiography with respect to different scanner techniques. Moreover, implications for radiation exposure and left ventricular function analysis are discussed.  相似文献   
29.
纵隔类癌的CT表现(附6例报道)   总被引:4,自引:0,他引:4  
目的:分析纵隔类癌的CT表现,探讨CT诊断价值。方法:对1994年一2001年经4所医院病理证实的纵隔类癌6例进行临床、病理、CT对照分析。结果:①临床无特异性表现,极少出现类癌综合征;②CT表现为中上纵隔肿块,位于胸腺区或向其内生长,与心底部大血管及心包关系密切,并有沿血管间隙生长的特点,造影后有轻、中度强化,可发生胸内外转移;③CT表现与病理、预后密切相关。结论:纵隔类癌较罕见,可能来源于胸腺。CT发现以上特点可提示诊断,还可观察肿块大小、位置、范围、内部及与血管心包的关系,帮助确定手术方案及推测预后,但确诊需依靠病理。  相似文献   
30.
易自生  刘一平  杨帆 《放射学实践》2003,18(10):729-730
目的 :探讨节细胞神经瘤的CT诊断。方法 :回顾性分析 4例经手术病理证实的节细胞神经瘤的CT表现 ,并结合相关文献复习 ,讨论其影像特征。结果 :肿瘤位于脊柱旁或肾上腺区 ,直径均 >3 .5cm ,呈卵圆形 ,有完整包膜 ,呈较均匀低密度或欠均匀 ,多数病灶内可见点状高密度钙化。增强扫描呈轻度均匀或欠均匀强化。结论 :节细胞有一定的CT影像特点 ,CT能作出正确的定位及较准确的定性诊断  相似文献   
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