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21.
We have studied 3 cases of sarcoidosis involving the parotid gland by means of fine-needle aspiration cytology (FNAC). The main findings were noncaseating granulomas, multinucleated giant cells (MGCs), and lymphocytes. In one case MGCs contained asteroid bodies and in another case we observed calcium oxalate crystals (COCs) over both stromal fragments and MGCs. Although nonpathognomonic for sarcoidosis, these 2 findings may help in the diagnosis of this condition. However, both are easily overlooked and must be borne in mind when viewing noncaseating granulomas. Sarcoid granulomas displaying COC must be differentiated from foreign-body granulomas. The aforementioned cytological findings must be assessed in conjunction with clinical findings. Nevertheless, in most cases the diagnosis of sarcoidosis is made by exclusion.  相似文献   
22.
Ameloblastic fibroma of the jaw is a rare, benign mixed odontogenic tumor, having little tendency for local invasion and a low recurrence rate. Cytologic distinction from ameloblastoma, ameloblastic fibrosarcoma, and intraosseous adenoid cystic carcinoma is necessary, in view of the different biologic behavior. A painful, slow-growing swelling of the jaw in a 5-yr-old child clinicoradiologically considered as a benign cystic lesion was aspirated. Sheets of small monomorphic epithelial cells with peripheral palisading by columnar cells were seen on cytology smears. The striking feature was central hyaline globules in some tubules. A cytologic possibility of adenomatoid odontogenic tumor was suggested. Histopathology, however, confirmed it to be an ameloblastic fibroma.  相似文献   
23.
A case of multiple myeloma diagnosed by fine-needle aspiration (FNA) biopsy and confirmed by laboratory studies in a patient with a history of renal-cell carcinoma is presented. The patient was diagnosed with renal-cell carcinoma of the right kidney and a radical nephrectomy was performed. Eighteen months after this diagnosis was made, the patient developed chest wall pain and was found to have osteolytic bone lesions of the ribs and vertebral bodies. FNA of an osteolytic rib lesion disclosed multiple myeloma. Additional laboratory studies confirmed the diagnosis of multiple myeloma. This case report demonstrates the value of FNA as a diagnostic tool for the follow-up of cancer patients, the subsequent discrimination between metatastic lesions and a second primary malignancy, and the cytology of multiple myeloma.  相似文献   
24.
25.
A new approach to the automatic extraction of the lumen region and its boundary for gastrointestinal (GI) endoscopic images is presented. First, a quasi region of interest, the darker regions of the image, is segmented using a region splitting scheme termed progressive thresholding. The centre of mass of this segmented region acts as a seed for further processing. Then the lumen region is obtained using a region growing technique called the integrated neighbourhood search (INS). A new quad structure based technique is introduced to enhance the INS speed significantly. A back projection algorithm is suggested to optimise the search for pixels belonging to the lumen region and boundary. A boundary-thinning algorithm is also proposed to remove the redundant pixels from the lumen boundary and to generate a connected single pixel width boundary. The proposed approach does not need a priori knowledge about the image characteristics. The experimental results indicate that the proposed technique enhances the speed of conventional INS by 45.5% to 28.6% based on the lumen size varying from 22,709 pixels to 4947 pixels. The main advantage of the proposed technique is its high-speed response that facilitates real-time analysis of endoscopic images.  相似文献   
26.
Tumoral calcium pyrophosphate dihydrate deposition disease (TCPPD, tumoral or tophaceous pseudogout) is a rare nonneoplastic entity which mimics soft-tissue or skeletal malignancy. We present here the fine-needle aspiration cytology findings of a unique case of TCPPD in a 76-yr-old woman, with a large paraischial soft-tissue mass diagnosed as a malignant neoplasm. The difficulty in diagnosing such lesions by fine-needle aspirates is discussed and reviewed in the context of known cases from the literature.  相似文献   
27.
We evaluated the diagnostic contribution of adjunct studies performed on aspirated material in the work-up of pediatric fine-needle aspiration (FNA) biopsies. Ancillary studies were performed on 54 of 136 (39.7%) pediatric FNA biopsies during a 5-year period. In 23 (16.9%) cases, immunocytochemical (ICC) studies, consisting of immunoperoxidase staining of direct smears and/or cell blocks or flow cytometric immunophenotyping, were performed. The studies were adequate in 14 cases (60.9%), suboptimal in five cases (21.7%), and inadequate in four cases (17.4%). Of the adequate and suboptimal cases, the ICC data helped to narrow the differential diagnosis or classify the disease process in eight cases (42.1%), confirmed cytologic impression in nine cases (47.4%), and gave contradictory results in two cases (10.5%). Adequate material for electron microscopy (EM) was obtained in 14/19 cases (73.7%). Ultrastructural studies were diagnostic, or helped classify the disease process in five cases (35.7%), confirmed the cytologic impression in four cases (28.6%), helped exclude diagnostic considerations in three cases (21.4%), and were judged to be non-contributory in two cases (14.3%). Cytogenetic studies revealed six of seven cases (all neoplasms) to have abnormal karyotypes. Special stains for organisms performed on smears from 25 cases including Ziehl-Neelsen, Gomori methenamine silver (GMS), Gram, and Warthin-Starry (WS) were negative except for 1/16 GMS and 4/9 Gram stains. In summary, we found that with appropriate case selection, ancillary studies performed on aspirated material can provide useful information in pediatric FNA cytology.  相似文献   
28.
Two cases of unusual benign tumors of the neck are described, both of which were initially misdiagnosed on cytology as carcinomas. Fine-needle aspiration findings in each case demonstrated a pleomorphic population of cells including bizarre multi-nucleated giant cells, the latter raising the false impression of malignancy. However, on review the cytological appearances of the tumors, a pleomorphic lipoma and a carotid body tumor, were characteristic. the correct diagnosis in each case would have been made or suggested if the pathologist had been familiar with the cytologic features characteristic of the lesion and the differential diagnosis of the head and neck tumors. in addition, the point is made that adequate clinical information is essential for the pathologist if all relevant conditions are not to be missed in the differential diagnosis.  相似文献   
29.
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   
30.
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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