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61.
Pseudoangiomatous stromal hyperplasia (PASH) is an uncommon lesion usually found in premenopausal women. Histologically, it is characterized by complex, anatomosing, empty slit-like spaces in a dense collagenous stroma. These pseudoangiomatous spaces are lined by monomorphic spindle cells of myofibroblastic differentiation. Cytological features of PASH are rarely discussed and reported, and may pose diagnostic challenge to surgical pathologists. Two cases of PASH are reported with emphasis on the FNAC features and cytologic differentiation from other benign fibroepithelial lesions. 相似文献
62.
María Francisca Garijo José Fernando Val‐Bernal Alfonso Vega Daniel Val 《Pathology international》2008,58(12):787-791
Despite the frequent use of fine‐needle aspiration, core biopsy and surgery, postoperative spindle cell nodule (PSCN) is a rare pathological complication that may be diagnostically treacherous. Presented herein is the case of a 52‐year‐old woman who developed a 7 mm mammary nodular lesion 66 days after removal of an area of columnar cell hyperplasia involving cellular and architectural atypia, performed with the Mammotome Breast Biopsy System. The lesion was highly cellular and composed of intersecting fascicles of plump spindle cells with blunt‐ended elongated nuclei and nucleoli easily visible. Interspersed mononuclear cells and hemosiderin‐laden macrophages were evident. PSCN is a reactive, benign myofibroblastic proliferation. Differential diagnosis includes benign and malignant spindle cell lesions of the breast. Recognition of this reactive lesion will avoid overdiagnosis of spindle cell malignant tumor. Attention to clinicopathological and histological features should result in accurate recognition of this lesion. 相似文献
63.
A variety of neoplastic and nonneoplastic lesions of the salivary glands have a predominantly cystic architecture. Fine-needle aspirates of these lesions yield watery or mucoid material, frequently of low cellularity. Such aspirates may be obtained from mucus retention cysts, lymphoepithelial cysts, cystadenomas, Warthin's tumors, cystic pleomorphic adenomas, low-grade mucoepidermoid carcinomas, cystadenocarcinomas, and examples of polycystic disease of the parotid gland. The cellular component within the fluid obtained from these lesions may be exceedingly scant or absent, making cytologic diagnosis difficult and, at times, impossible. We studied a series of 56 cystic lesions of the salivary glands, including 38 Warthin's tumors, 6 benign cysts, 2 lymphoepithelial cysts, 5 low-grade mucoepidermoid carcinomas, 1 cystic pleomorphic adenoma, 2 cystadenomas, and 2 cystadenocarcinomas. Careful attention to the cellular elements present often allowed definitive cytologic diagnosis, with an overall accuracy rate of 84%. The presence of atypical squamous metaplasia in oncocytic lesions was a significant cause of false-positive diagnoses of carcinoma (4 cases, 7%). Aspirates of low-grade mucoepidermoid carcinoma may contain no epithelial cells and result in false-negative diagnoses (1 case, 2%). 相似文献
64.
In this present series, we studied in detail the cytologic features of five histopathologically verified cases of central giant-cell granuloma (CGCG). All the patients in this series were female, with an age range of 11-60 years. There were three cases with involvement of the lower jaw and two cases had upper jaw involvement. Cytology smears showed dispersed single cells in the background. Nuclei of the individual cells were round to ovoid with fine chromatin and inconspicuous nucleoli. The cytoplasm of these cells was moderate in amount with indistinct cell borders. Many randomly scattered multinucleated giant cells with 10-20 nuclei were present in the background. Combination of clinical features, radiologic pictures, and cytologic features may be helpful for diagnosis of CGCG on fine-needle aspiration cytology. 相似文献
65.
An unusual case study of a desmoplastic small round cell tumor presenting as a 3.5-cm, firm, supraclavicular neck mass and diagnosed by fine-needle aspirate biopsy in a 16-yr-old male is reported. Clinical, cytologic, and immunocytochemical findings are described. Histologic, immunohistochemical, and genetic features are discussed. Desmoplastic small round cell tumor should be considered in the differential diagnosis of small round cell tumors of any site; the importance of ancillary studies in arriving at the correct diagnosis is emphasized. 相似文献
66.
Salamanca J Rodríguez-Peralto JL Azorín D Ballestín C De Agustín P 《Diagnostic cytopathology》2004,30(1):46-50
We report the FNA features of a congenital malignant extrarenal rhabdoid tumor (MERT) located in the right paratesticular area of a newborn full-term boy (39 wk gestation), with disseminated metastases in the liver and right parietal region. The diagnosis was suggested two days after birth by fine-needle aspiration biopsy (FNAB) of the parietal mass, which demonstrated an atypical large cell proliferation with vesicular nuclei, prominent nucleoli, and abundant cytoplasm exhibiting paranuclear dense inclusions. The diagnosis was confirmed by histopathologic and immunohistochemical examination of the primary paratesticular tumor. To the best of our knowledge, this is the third MERT reported in the paratesticular region, one of the few congenital extrarenal non-central nervous system cases, and the third congenital case (renal or extrarenal) primarily diagnosed by FNAB. We emphasize the characteristic cytologic features of a congenital rhabdoid tumor, which must be known by pathologists because of the clinical and prognostic implications. Diagn. Cytopathol. 2004;30:46-50. 相似文献
67.
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
68.
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
69.
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
70.
Marilyn Y. McGinnis Christopher P. Phelps Dwight M. Nance Bruce S. McEwen 《Physiology & behavior》1982,29(2):225-229
Retrochiasmatic frontolateral knife cuts (FLC) or sham operations (Sham) were performed with a Halasz-type knife. All animals were primed with estrogen plus 0.5 mg progesterone (P) and tested for lordosis both before and after surgery. Two weeks after the last test they received estradiol (E2) in Silastic capsules and were sacrificed 2 days later for determination of either nuclear estrogen receptors or cytosol progestin receptor binding in brain and pituitary (PIT). Rats which had received FLC showed significantly lower lordosis quotients relative to Shams, and relative to their own pre-surgery scores. Nuclear E2-receptor binding was significantly reduced in the hypothalamus (HYPO) following FLC, but not in preoptic area (POA) or PIT. No changes in cytosol P-receptor binding were observed in HYPO, POA or PIT following FLC. Our results suggest a positive correlation between the number of hypothalamic E2-receptors and the capacity to display lordosis, and emphasize the importance of anterolateral connections to the HYPO for the progesterone-induced facilitation of lordosis. 相似文献