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101.
We report the cytological and clinical findings of 16 fine-needle aspirates (FNAs) performed on recurrent (n = 6) and metastatic (n = 10) mixed mesodermal tumors (MMMTs). The median interval between the primary diagnosis and FNA was 16 mo. Primary sites were the endometrium (n = 11), the ovary (n = 3), the cervix (n = 1), and pelvic soft tissue (n = 1). Primary tumors showed carcinoma with homologous mesenchymal components in 13 cases and focal heterologous elements in three (two chondrosarcomas and one rhabdomyosarcoma). The FNAs showed carcinoma in all 16 cases, with adenocarcinoma differentiation in three, Mesenchymal elements were identified in aspirates of three recurrent and two metastatic lesions. They were all homologous. No heterologous mesenchymal elements were identified in the aspirates. We conclude that mesenchymal components in FNAs of MMMTs are less likely to be seen in metastatic lesions, and that heterologous mesenchymal components are rarely seen in these aspirates even in recurrent disease. These findings confirm that the epithelial component is responsible for the malignant behavior of MMMTs, and suggest that these lesions may need to be classified as sarcomatoid carcinomas rather than true carcinosarcomas. Diagn Cytopathol 1994;11:328–332. © 1994 Wiley-Liss, Inc.  相似文献   
102.
Pseudomyxoma peritonei is the clinical term for the diffuse deposition of mucus within the peritoneal cavity secondary to a mucinous tumor of the ovary or appendix. This gelatinous ascites, or "jelly-belly," may result in death from loss of intestinal function and intestinal obstruction caused by peritoneal implants rather than visceral invasion. Microscopic evaluation of peritoneal fluid is frequently an initial diagnostic test; however, in a search of the recent literature we were surprised to find only one case report of the cytologic features. This prompted us to report the cytologic findings in the peritoneal fluid of two cases of pseudomyxoma peritonei arising from appendiceal mucinous cystadenomas.  相似文献   
103.
The histopathologic features of malignant peripheral nerve sheath tumors (MPNSTs) have been well described. There have been limited studies on the cytologic features of MPNST. In this present study, we have retrospectively reviewed eight histopathology confirmed cases of MPNST over a 5-year period. Detailed cytomorphological analysis of these cases was carried out individually by two observers. On cytology, these cases were diagnosed as benign spindle-cell tumor (two), spindle-cell tumor possibly benign (one), spindle-cell tumor possibly malignant (one), malignant spindle-cell tumor (two), spindle-cell tumor, and neural origin (two). The cardinal cytomorphologic features were loosely cohesive clusters and fascicular arrangement of spindle cells with rounded ends. The kinking of nuclei was not a conspicuous finding. Fibrillary background was noted in two of the cases. Nuclear pleomorphism was ranged from mild to moderate degree. One case exhibited extensive intranuclear pseudoinclusions. Mitotic figures (including atypical forms) were present in almost all the cases. Possibly a constellation of cytologic features such as clusters of short and long fascicles of cells admixed with dissociated spindle cells of round-ended nuclei and prominent nucleoli on myxoid or fibrillary background and frequent mitosis may be helpful in diagnosis of MPNSTs. The cytomorphologic features along with clinical correlation are necessary to increase the diagnostic accuracy of MPNST on aspiration cytology.  相似文献   
104.
We performed an electron microscopic study of cytologic material from 20 cases of primary lung adenocarcinoma (pleural effusion, 13 cases; fine needle aspiration biopsy, 7 cases). Ultrastructural characteristics related to secretory and storing activity of adenocarcinoma cells were evaluated semi-quantitatively. Data analysis identified three basic cell types (secretory, well or poorly differentiated; storing; and indifferent). We could classify our cases in five groups of pure or mixed cytotypes. Our results demonstrated a subcellular morphological heterogeneity manifested by the presence of different basic cell types: secretory, storing or indifferent features (or both); and different secretory and storage products in the same cell. This heterogeneity of lung adenocarcinoma cells suggests that the neoplasm could arise from a single cell type capable of differentiating along different lines. Cases lacking secretory differentiation seemed to be characterized by more aggressive biologic behavior. A clear correlation between the ultrastructural cytotypes identified and the clinical and prognostic data on the patients was not observed. This may be due to the fact that 75% of the patients were in clinical stage III at the time of diagnosis; also, in this series only five cases did not have characteristics that indicated secretory activity.  相似文献   
105.
In its pure form, mucinous breast carcinoma (MC) has a much better prognosis than infiltrating ductal carcinoma (IDC). Mixed MC-IDC has the prognosis of IDC. We compared the fine-needle aspiration (FNA) cytology and histology of nine cases of pure MC with 13 cases of mixed MC-IDC. While typical of pure MC, abundant mucin (3+/3+) was noted in smears from three cases of mixed tumor and is thus necessary but not sufficient for a diagnosis of pure MC. Cellular pleomorphism has been said not to be a feature of MC; however, we found occasional large cells markedly different from the typical small uniform cells of MC in four pure and seven mixed tumors. Cytologic features indicative of a mixed tumor include one or more smears totally without mucin, scantly amounts of mucin, or necrosis. A combination of features indicative of pure mucinous carcinoma in FNA included abundant mucin on all smears, no pleomorphism, and no necrosis. Many cases will have smear patterns that are not typical of either profile and should probably be designated as carcinoma with a mucinous component.  相似文献   
106.
Two cases of small-cell carcinoma of the ovary in the ascitic fluid and peritoneal/pelvic washings of a 30- and 28-yr-old woman, respectively, are presented and discussed. Smear preparations from the ascitic fluid showed loose clusters and single malignant cells with scant cytoplasm and nuclei with smooth to irregular nuclear membranes, granular chromatin, and small nucleoli. In the second case peritoneal/pelvic washing specimens contained clusters and single malignant cells with a moderate amount of cytoplasm and nuclei with smooth nuclear membranes, granular, clumped chromatin, and prominent nucleoli. Histology confirmed the diagnosis of small-cell carcinoma of the ovary. These are the first reported cases of this rare ovarian neoplasm present on fluid cytology. Its differentiation from other small-cell neoplasms on peritoneal fluid cytology from young women is discussed. Diagn Cytopathol 1994; 11:266–270. © 1994 Wiley-Liss, Inc.  相似文献   
107.
Fine-needle aspiration biopsy of tibial adamantinoma: a case report   总被引:1,自引:0,他引:1  
Adamantinoma of long bones is a rare, primary bone tumor of controversial histogenesis, usually arising in the anterior midshaft of the tibia. This slowly growing, radiolucent, expansile tumor eventually causes thinning or destruction of overlying cortical bone. Fine-needle aspiration biopsy (FNAB) is a rapid, safe, and relatively painless means of obtaining diagnostic material from bone tumors, provided the mass has eroded through or markedly attenuated the overlying cortex. A case is presented of primary adamantinoma of the tibia which was sampled first by FNAB and subsequently by surgical biopsy.  相似文献   
108.
Fine-needle aspiration biopsy of the pancreas: a study of 61 cases   总被引:1,自引:0,他引:1  
Eighty-six fine-needle aspirates (FNAs) of pancreas from 74 patients were reviewed. Histological confirmation or clinical follow-up of the final diagnosis was available in 61 aspirates from 49 patients. Of 42 proven malignant cases, FNAs were diagnosed as positive in 21 (50%), suspicious in 4 (9.5%), negative in 12 (28.6%), and unsatisfactory in 5 (11.9%). Of 19 proven benign cases, FNAs were diagnosed as negative in 15 (78.9%) and unsatisfactory in 4 (21%). This resulted in a 50% sensitivity, a 100% specificity, a diagnostic efficiency of 59%, a predictive value of a positive test of 100%, and a predictive value of a negative test of 55.6%. Thirty-six primary pancreatic adenocarcinomas and six metastatic tumors to the pancreas were encountered. Benign cases were attributed to anatomical pancreatic variants, acute pancreatitis, abscess, chronic pancreatitis, and pseudocysts. Pancreatic FNA was safe, accurate, and relatively inexpensive, but it was relatively insensitive in the diagnosis of malignancy.  相似文献   
109.
The cytological evaluation of ovarian cystic fluid using ThinPrep has not been reported. To determine the diagnostic accuracy of ThinPrep cytology in distinguishing between benign and nonbenign ovarian cystic lesions, we examined 65 fluid samples aspirated during intraoperative consultation with subsequent histologic correlation. One ThinPrep slide was prepared from each sample aspirated from surgically removed ovarian cystic masses and reviewed blindly by a panel of three cytopathologists. The parameters used in cytological evaluation were cellularity, cell types, cellular arrangement, and background. Four samples were acellular and excluded from the study. The consensus cytologic diagnoses were compiled for 61 cases which were assigned to one of the following diagnostic categories: negative for malignant cells (40 cases), atypical cytology (13 cases), and suspicious or positive for malignancy (8 cases). Histologic correlation of the cytological benign/negative cases showed that 26/40 (65%) were histologically benign and 14/40 were false-negative (35%, 5 carcinomas and 9 borderline tumors) with 10 of these cases being mucinous tumors. Most false-negative cytologic samples (11/14 or 79%) did not have an epithelial component. Of the 21 cytological nonbenign diagnoses (atypical/suspicious/positive), 15 (71%) were confirmed on histology (10 carcinomas and 5 borderline tumors). However, a nonbenign cytologic diagnosis was rendered in 6 histologically benign cases, including 2 serous cystadenomas, 1 mucinous cystadenoma, 1 serous cystadenofibroma, 1 endometriosis, and 1 corpus luteal cyst. The diagnostic sensitivity by ThinPrep evaluation of ovarian cystic masses is 81% (26/32) for benign and 52% (15/29) for nonbenign lesions. Our results concluded that ThinPrep examination of ovarian cystic fluid is not accurate in distinguishing benign from malignant cysts, given the significant number of false-negative diagnoses. Major contributing factors include sparse cellularity of the fluid samples and mucinous differentiation of the tumors.  相似文献   
110.
We report on the cytopathologic findings of a Leydig-cell tumor of the testis in a young adult male with no evidence of endocrine dysfunction. The preoperative diagnosis was based on fine-needle aspiration cytology (FNAC) alone, which was subsequently confirmed on histopathology. The present case was of interest on account of the paucity of literature regarding the cytodiagnosis of this lesion. In addition, the finding of intracytoplasmic lipofuscin pigment and several intracytoplasmic as well as intranuclear Reinke's crystals served to clinch the diagnosis on FNA. Therefore, the use of FNAC, especially in the presence of diagnostic Reinke's crystals, may vitiate the need for more invasive biopsy procedures in the preoperative diagnosis of testicular Leydig-cell tumors.  相似文献   
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