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81.
Adenoid cystic carcinoma of the lower respiratory tract is an uncommon tumor that can arise in the mainstem bronchus and often presents as an endobronchial mass lesion causing bronchial obstruction with post obstructive atelectasis and pneumonia. Exfoliative cytology is seldom useful in the diagnosis of primary bronchial adenoid cystic carcinoma, because these neoplasms usually have a submucosal location with often intact mucosa. Since most endobronchial adenoid cystic carcinomas are endoscopically visible, bronchoscope-guided fine-needle aspiration constitutes an excellent approach to establish a pathologic diagnosis. The fine-needle aspiration cytology of primary pulmonary adenoid cystic carcinoma has been rarely described. We report a case of primary adenoid cystic carcinoma of the lung having characteristic cytologic features and correlate with computed tomography, bronchoscopic, and histological findings. Bronchoscope-guided aspiration cytology provided a conclusive diagnosis of adenoid cystic carcinoma, which was further corroborated by histology in the pneumonectomy specimen. Diagn. Cytopathol. 2004;30:51-56.  相似文献   
82.
To investigate the pulmonary haemodynamic effects of meconium aspiration and subsequent adenosine triphosphate (ATP) treatment, 12 anaesthetized and ventilated pigs (wt 24-28 kg) received either ATP or an equal volume of saline into the right heart in doses of 0.02 to 0.80 lmol kg-1 min?1 after intratracheal administration of 2 mL kg?1 of human meconium. Meconium instillation induced significant increases in pulmonary vascular pressures and total and postarterial resistances calculated from pulmonary artery occlusion studies, but did not affect the systemic haemodynamics, except for a fall in heart rate and increase in central venous pressure. Infusion of ATP at the lowest doses (0.02 and 0.08 µmol kg?1 min?1) selectively decreased the pulmonary arterial pressure and vascular resistance and at 0.32 and 0.80 µmol kg?1 min?1 reduced both the pulmonary and systemic resistances. In the lung circulation the increasing doses of ATP reduced preferably the arterial, but also the postarterial resistance. Withdrawal of ATP infusion led to a significant rebound effect especially in the postarterial segment of the lung circulation. Meconium aspiration thus induces an acute, predominantly postarterial obstruction in the lung circulation and infusion of ATP at low doses selectively dilates the pulmonary vascular bed and may help to preclude elevation of capillary pressures in meconium aspiration-induced pulmonary hypertension.  相似文献   
83.
Fine-needle aspiration cytology (FNAC) plays a key role in the preoperative diagnosis of breast carcinoma but is less reliable in the diagnosis of in situ lesions. The objective of the present study was to investigate the cytological features of lobular carcinoma in situ (LCIS), regarding which little data is available to date. Cytological features of FNAC of the breast from 21 patients with histology-proven LCIS were described and compared with surgical specimens. Aspirates from 8/21 cases had cell groups diagnostic for or compatible with LCIS. Aspirates from an additional two cases demonstrated hypercellular, dissociated, and more pleomorphic tumor cells, which were originally diagnosed as invasive lobular carcinoma (ILC). The remaining 11 aspirates were diagnosed as benign or nondiagnostic. FNAC from the eight diagnostic specimens were characterized by loosely cohesive cell groups composed of uniform cells with occasional intracytoplasmic lumina, slightly irregular and eccentric nuclei. We conclude that the main difficulty in diagnosing LCIS by FNAC is sampling rather than recognition of the lesions. However, one should be aware of the cytological features of LCIS in order to reach a correct diagnosis. There are no reliable cytological criteria that help in differentiating pleomorphic and dissociated LCIS from ILC.  相似文献   
84.
Fine-needle aspiration (FNA) is a reliable, safe, and cost-effective procedure with a well-established role in the diagnosis of various solid tissue neoplasms. The role of FNA in the diagnosis of primary bone tumors, including osteosarcoma (OGS), is controversial and has yet to be established. We reviewed our experience with the use of FNA as a diagnostic technique over the past 8 yr at our institution. Diagnosis was conclusive in 26 (65%) of 40 patients, 18 of whom went to neoadjuvant therapy and/or resection based solely on the FNA interpretation of either "high grade sarcoma" or "osteosarcoma." Of the remaining 14 (25%) patients, 12 had inconclusive diagnosis and two (5%) were false-negatives. An inconclusive diagnosis was most likely to be an inadequate or paucicellular aspirate, seen in six (15%) patients. An additional six patients had variants of osteosarcoma (four chondroid, one "giant cell rich," one parosteal) that made definitive diagnosis impossible. The two that were incorrectly classified were diagnosed as fracture callus and plasmacytoma. FNA is an accurate and cost-effective tool for the initial diagnosis of primary osteosarcoma with a sensitivity of 65% and accuracy of 95%. Inconclusive diagnoses are likely to be due to insufficient sample cellularity or the presence of OGS variant. In our experience, FNA is sufficient to provide the diagnosis of OGS prior to definitive treatment when interpreted in conjunction with imaging studies and clinical findings. In those cases where FNA fails to yield a diagnostic sample, a traditional biopsy can be performed.  相似文献   
85.
This article reports the cytodiagnosis of three cases of retinoblastoma in children aged 1.5, 2.5, and 5 yr. Two of them were diagnosed by fine-needle aspiration cytology of the primary tumor and one by aqueous cytology. The tumor cells were usually round to oval, small and uniform, with scanty cytoplasm; they generally occurred in closely packed clusters of variable sizes. We discuss the differential diagnosis of retinoblastoma with other round-cell tumors of childhood involving the orbit.  相似文献   
86.
Seven cases of spindle-cell proliferations in which fine-needle aspiration biopsy (FNAB) did not correlate with subsequent histology are presented. Three cases were considered low-grade sarcoma, one a dermatofibrosarcoma protuberans (DFSP), one a spindle-cell tumor with malignancy not excluded, and one a rhab-domyosarcoma vs. a fibrosarcoma. Two of the these three were histologically nodular fasciitis and one an inflammatory pseudotumor. Two cases were diagnosed cytologically as fibromatosis or nodular fasciitis (NF). One of these histologically was an intramuscular hemangioma, the other a DESP. The last two cases were diagnosed by FNAB as spindle-cell lesion, undetermined if benign or malignant, and malignant fibrous histiocytoma (MFH). Histologically both of these case were leiomyosarcoma. The cyto-logic features of each case, differential diagnosis, and potential pitfalls are discussed. In the evaluation of FNAB smears dominated by spindle cells, cellullarity, individual cells and cell patterns,and background stromal features coupled with a precise clinical history may allow a narrow differential diagnosis with a focus on whether the lesion is benign or malignant. Caution is warranted in the exact classification of spindle-cell tumors from FNAB as this may have a major impact on patient management. © 1994 Wiley-Liss, Inc.  相似文献   
87.
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   
88.
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   
89.
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   
90.
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   
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