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1.
The cytologic findings in peritoneal washings of two women, one of whom had an ovarian ependymoma and the other a primary omental ependymoma, are reported. The ependymomas were characterized by the presence of numerous, isolated, spindle and stellate cells as well as groups of cells forming true rosettes. The tumor cells displayed slightly pleomorphic, round-to-oval eccentric nuclei and abundant fibrillary cytoplasm with tapering cytoplasmic processes. In addition, one of the patients had numerous papillae and cell clusters with associated psammoma bodies indistinguishable from those found in low-grade serous carcinoma. The demonstration of glial fibrillary acidic protein (GFAP) in both cases by immunocytochemical procedures indicates the usefulness of this method in cytologic preparations to confirm the diagnosis of these uncommon neoplasms.  相似文献   
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3.
A case of primary amyloidosis, initially detected by fine-needle aspiration of the liver, is reported here. Amorphous acellular metachromatic material was seen extracellularly in between the hepatocytic cords compressing them. This material showed typical apple-green birefringence under crossed bipolars after alkaline Congo-red staining proved its amyloid nature. It was resistant to potassium permanganate pretreatment, indicating it to be of the AL type. © 1994 Wiley-Liss, Inc.  相似文献   
4.
The gross and microscopic appearances of aspirates from ten intramuscular myxomas are reported. The specimens were obtained from seven women and three men, ages 43 to 75, who had tumors involving the muscles of the thigh (7), upper arm (2), and forearm (1). Magnetic resonance (MR) imaging performed in six of the ten cases revealed well-defined, sharply demarcated tumors exhibiting low signal intensity relative to muscle on the T1-weighted images. The tumors were hyperintense to muscle on T2-weighted images. All aspirated tissues were clear, tenacious, and viscous. Smears contained few spindled and histiocytoid cells in an abundant mucoid background. Spindle cells demonstrated long cytoplasmic processes that in areas intertwined to form fibrillar tangles. Nuclei were oval to spindled with fine chromatin and inconspicuous nucleoli. Capillaries were sparse with simple (nonplexiform) branching. The differential diagnosis of myxoid lesions of the extremities includes benign entities such as myxoid schwannoma and neurofibroma, mesenchymal repair, and ganglion cyst, as well as malignant neoplasms such as myxoid liposarcoma, fibrosarcoma, malignant fibrous histiocytoma, and extraskeletal chondrosarcoma. The findings of this study revealed that, although the cytologic features were suggestive of intramuscular myxoma, a definitive diagnosis was often difficult, owing to scant cellularity and lack of distinctive cytologic features. The MR imaging findings may be utilized as an adjunct to the cytologic features to more confidently suggest a diagnosis of intramuscular myxoma. Diagn Cytopathol 1994;11:255–261. © 1994 Wiley-Liss, Inc.  相似文献   
5.
Sixty-two cases of breast pathology were randomly selected from the files of the Dunedin Public Hospital for evaluation of mean epithelial nuclear volume. The cases were comprised of both benign and malignant ductal epithelial disease, diagnosed in cytological smears or in histological sections. Nuclear volume in histological preparations was estimated by the stereological technique of point-line intercept measurements to derive volume-weighted mean volumes (vV). An index of the nuclear volume (Vi) of cytology smears was calculated from measurements of nuclear areas by either image analysis Vi(e) or point-line intercepts Vi(p). By all methods of analysis a clear distinction of nuclear volume was found between the benign [means for the cytology were 148 microns 3 (Vi(e)) or 246 microns 3 (Vi(p)), and 203 microns 3 (Vv) for the histology specimens] and malignant diseased cases [means for cytology: 524 microns 3 (Vi(e)) or 886 microns 3 (Vi(p)), and 587 microns 3 (vV) for the histology specimens].  相似文献   
6.
The cytologic findings of juvenile papillomatosis (JP) have been rarely described. The clinical and cytologic findings were suggestive of a fibroadenoma, but due to the presence of 2 cc of clear fluid during the aspiration, fibrocystic change was in the differential diagnosis. Operation and subsequent examination of the mass identified a case of JP (so-called Swiss cheese disease of the breast). Because JP is a marker for breast carcinoma for the patients' families, and the patients may themselves be at increase risk for malignancy, it is important that this entity be considered in the differential diagnosis. The observations in this case indicate that it is difficult to diagnose JP only by cytology, but the combination of clinical findings—a well-circumscribed mass in a young patient with cystic fluid, but with a residual mass after aspiration due to the multicystic nature of JP—with the cytologic findings—sheets of hyperplatic breast epithelium with areas resembling fibroadenoma, macrophages, and apocrine cells—that appear to be sufficiently characteristic to suggest the diagnosis of JP.  相似文献   
7.
The cytologic features of ascitic fluid in a case of malignant fibrous histiocytoma (MFH) of the colon are described. At autopsy, two solid tumor masses were found around the ascending and transverse colon, accompanied by about 3,000 ml of ascites. Tumor cells had infiltrated diffusely into the outer layers of almost all of the gastrointestinal wall, simulating peritonitis carcinomatosa. Cytologic examination of the ascites revealed various kinds of tumor cells; short spindle-like cells, multinucleated giant cells, and round cells with an invaginated nuclear margin, forming small clusters. These cytologic findings were considered to be very useful in the diagnosis of MFH, especially in cytologic examinations of ascites. ACTA PATHOL JPN 38: 921 ∼ 928, 1988.  相似文献   
8.
Cytological scrape material of the oral mucosa from 114 patients with epithelial dysplasia and with oral cancer was stained with the Feulgen-reaction and investigated with an image analyzer. The size and the integrated optical density of cell nuclei, and four chromatin texture features were measured. All tumor slides contained cell nuclei with DNA greater than 5c, 16% of the slides had cell nuclei with DNA greater than 8c. A total of 14.5% of the tumor patients showed significantly increased DNA values in nuclei distant from the tumor. Two smears with severe epithelial dysplasia showed nuclei with DNA greater than 5c both in the tumor material and far from the tumor. Texture analysis allowed discrimination between benign, dysplastic and malignant smears. No correlation was found between DNA content and tumor staging. Image cytometry was a reliable method for detecting tumor cells. Epithelial dysplasia in areas distant from the tumor is probably due to "field canceration" of the epithelium.  相似文献   
9.
We report two cases of metastatic adamantinoma to the lung diagnosed by FNAB. The cytologic appearance of the smears of each case was homogenous, containing small round and spindle cells with indistinct cytoplasm. The nuclei had delicate nuclear membranes, with finely dispersed chromatin and occasional micronucleoli. No pleomorphism was noted. Immunocytochemistry exhibited positive staining for keratin and vimentin. EM examination revealed numerous tonofilaments and well formed desmosomes. The cytologic diagnosis of metastatic adamantinoma can be made with the knowledge of a previous history of adamantinoma of bone, the comparison of the metastatic tumor with the original bone tumor, and the awareness of the long latency of the metastases. Immunocytochemistry and EM are needed to substantiate the diagnosis. © 1994 Wiley-Liss, Inc.  相似文献   
10.
Melanoma, a not uncommon tumor, is associated with variable cytomorphology and unpredictable metastatic potential. Although most cytologic diagnoses of malignant melanoma represent metastatic disease, the diagnosis is frequently unsuspected clinically. Three effusions in which cells from metastatic melanomas were not diagnosed are described. Clinical factors that may have contributed to the erroneous cytodiagnoses are illustrated. Cytologic features and adjunctive studies that are helpful in identifying melanoma cells are discussed.  相似文献   
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