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51.
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
52.
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
53.
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
54.
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
55.
Diagnostic value of DNA flow cytometry combined with fine needle aspiration biopsy in lymphomas 总被引:2,自引:0,他引:2
The nuclear DNA content of cells from 45 malignant lymphomas and from 60 benign lymph nodes obtained by fine needle aspiration was analysed to investigate the diagnostic value of DNA flow cytometry combined with routine diagnostic cytology in lymphomas. DNA aneuploidy was found in 43 per cent of lymphomas of high grade malignancy (NCI Working Formulation) but only rarely in lymphomas of intermediate- or low-grade malignancy or in Hodgkin's disease, and never in benign lymph nodes. The median percentage of proliferative cells (S + G2/M) was 22.6 per cent in diploid high-grade lymphomas, 15.3 per cent in intermediate-, and 8.1 per cent in low-grade lymphomas, as compared with 4.9 per cent in benign lymph nodes (P less than 0.0001). If the presence of DNA aneuploidy or more than 12 per cent of proliferative cells is used as a criterion for malignancy, the diagnostic accuracy of DNA flow cytometry in detecting lymphoma is 81 per cent. DNA flow cytometry suggested correct diagnosis in 10 of the 19 false positive, false negative, or indeterminate cytological findings encountered during the study. It is concluded that DNA flow cytometry combined with fine needle aspiration biopsy has diagnostic value in lymphomas, but false negative results are common especially in low-grade lymphomas; the method should therefore be used in conjunction with light microscopy. 相似文献
56.
Fine-needle aspiration cytology of phyllodes tumors 总被引:3,自引:0,他引:3
Breast lesions with a significant spindle cell or mesenchymal component are not commonly encountered in fine-needle aspiration (FNA) cytologic material and include a heterologous variety of benign and malignant conditions, with phyllodes tumors (PTs) being the foremost differential diagnostic consideration. This study comprises 28 tumors diagnosed histologically as PT in which FNAC material was available for review. Histological sections and cytological smears from these cases were retrieved and subjected to detailed morphological review. Cytological parameters assessed included ratio of stroma to epithelium, pattern characteristics and cytological characteristics of the stromal, and epithelial components and the background cells. Large and hypercellular stroma fragments, dissociated spindle and plump stromal cells, often accompanied by large, folded sheets of epithelium were cytological features that characterized PT. Smears from malignant PT showed predominantly or solely mesenchymal components. FNAC was a highly reliable procedure for the diagnosis of PT, giving an accuracy rate of 92.8%. 相似文献
57.
Pancreatoblastoma is a rare tumor and has been reported only four times in the cytologic literature, three times in fine-needle aspiration (FNA) biopsy and once in an imprint of resected tumor. We are reporting the fourth case of FNA cytology with immunohistochemical and electron microscopic studies. The patient is a 24-yr-old African American woman, who presented with a pancreatic mass, hepatic masses, and abdominal lymphadenopathy. The aspiration smears of the liver mass showed a biphasic tumor composed of bland-appearing primitive spindled stromal fragments with "spider-web"-like long fibrils interconnecting with sharply angulated islands of cohesive epithelium. At high power, the epithelium is composed of medium-sized cells with round-to-oval vesicular nuclei with fine chromatin and one-to-two small nucleoli. The neuroendocrine component was demonstrated immunohistochemically with synaptophysin and chromogranin expressions. The acinar component and squamoid component were demonstrated ultrastructurally by the presence of 400-600 nm zymogen granules and tonofilaments. The literature was reviewed and the cytological features of all the four cases of pancreatoblastoma are summarized. 相似文献
58.
The fine-needle aspiration cytologic findings of Wilms' tumor occurring in a 20-yr-old female patient and a 35-yr-old male patient showing blastemal, spindled sarcomatous and rare epithelial components are reported. The male patient had the typical presentation of renal mass with metastasis to lung and pleura, whereas the female patient had an unusual presentation with the tumor originated from the subcapsular nephrogenic zone of the kidney, extending into the liver without invasion into the renal cortex. Cytogenetic analysis of this case identified: 90, XXXX, +2x3-4, -5, -15, -16, -17, -17, i (17)(q10) x2. This finding may represent a genetic change associated with Wilms' tumor of older pediatric and young adult patients. To the best of our knowledge, this case is the sixth case with cytogenetic study and the first case revealing isochromosome 17q of an adult Wilms' tumor. 相似文献
59.
Nonulcerative penile mass lesions are rare. Pathological diagnosis of these lesions would traditionally be a biopsy. We report two such primary penile lesions which were diagnosed by fine-needle aspiration cytology (FNAC). Both lesions were present in the shaft and were diagnosed as squamous cell carcinoma (SCC). The first patient had a recurrence on the penile stump of partial amputation without any ulceration. The second had a primary urethral carcinoma on the terminal penile shaft infiltrating the corpora cavernosa dorsally. Open biopsies were avoided in both cases. FNAC was associated with very little and tolerable discomfort. There were no complications. The aspirate yield was sufficient for cytological diagnosis. FNAC of nonulcerated penile lesions is safe, well tolerated, and capable of providing a cytological diagnosis. Hence, it is a very useful outpatient procedure and could be the procedure of choice for diagnosis. 相似文献
60.
CT引导下经皮穿刺活检术在肺癌诊断中的应用 总被引:1,自引:0,他引:1
目的 探讨CT引导下穿刺活检术在肺癌诊断中的准确性和并发症发生率。方法 40例使用弹簧芯状活检针经皮穿刺活检,CT扫描确定并引导穿刺途径,达预定位置取材。结果 37例有明确的病理诊断,诊断准确性92.5%。活检后并发气胸3例,咯血2例。结论 CT引导下经皮穿刺活检可以进一步明确肺癌的病理诊断,提高诊断的准确性,并发症发生率低,可为临床提供治疗依据。 相似文献