This study was performed in order to evaluate the accuracy and the usefulness of the cytology of crush preparation in central nervous system (CNS) lesions. Forty four intraoperative biopsies were performed at the time of craniotomy including 34 benign and 10 malignant lesions. Crush preparations were prepared from tiny tissue fragments of craniotomy products. All cases were stained with toluidine blue. Intraoperative diagnoses made on cytologic examination were compared with the final paraffin section diagnoses. Comparison between the results of the cytologic and histologic findings revealed an overall diagnostic accuracy of 88.6%. This study attests to the diagnostic accuracy of cytologic examination in CNS lesions. The detailed cytologic features are described and important criteria for the cytodiagnosis of CNS lesions are discussed. This review leads us to think that cytologic examination by crush preparation in CNS lesions is considered as a simple, safe and highly diagnostically accurate method.

There has been a marked increase in the utility of aspiration cytology for pathologic diagnosis. It may be applied to any kinds of organs and substitutes surgical biopsy. Be cause of the high risk of complication and difficulties In localization, aspiration cytology in the central nervous system (CNS) has been used with less frequency compared to other sites. However, with the advent of sophisticated imaging instruments, aspiration cytology of lesions in the CNS is being used increasingly. We present cytologic features of brain tumors as well as corresponding histologic findings. Eight types of tumors were aspirated intraoperatively and stained with the Papanicolaou method; 1 anaplastic astrocytoma, 1 glioblastoma multiforme, 1 ependymoma, 1 malignant ependymoma, 1 central neurocytoma, 1 primitive neuroectodermal tumor, 1 benign neurogenic tumor and 1 germinoma. Cytologic features of the CNS neoplasms were quite similar to those of histology except one spindle cell tumor. Reviewing various CNS neoplasms, it appears that cytology may be a useful diagnostic method.

We studied cervical cytology of 175 cases of histologically confirmed microinvasive squamous cell carcinoma of the uterine cervix in Cheil General Hospital from 1991 to 1993. Excluding 32 cases of insufficient smear, 143 cases were reviewed in view of background, cellularity, smear pattern, nuclear chromatin and presence of nucleoli. The characteristic findings of microinvasive carcinoma were syncytia and/or individual tumor cells in the focally necrotic inflammatory background. Nuclear chromatin was clear or fine. Nucleoli were observed in 55%. The prediction rate of microinvasive carcinoma was 74%. There is no significant relationship between the cellular features and depth of invasion.

Fine needle aspiration biopsy has been proved as a safe, accurate and cost-effective diagnostic modality in palpable breast lesions. Cytologically, fibrocystic disease can be classified into 3 categories as nonproliferative breast disease, proliferative breast disease without atypia, and proliferative breast disease with atypia. This terminology for fine needle aspirates is compatible with that of diagnostic histopathology. Cytologic differentiation of nonproliferative disease from proliferative breast disease is important, since the risk of cancer development in cases of atypical hyperplasia is 4-5 times higher than that of general population. Twenty five fine needle aspirates of fibrocystic disease confirmed by subsequent histopathology were re-evaluated and classified into 3 categories depending on their architectural and nuclear features. In addition, these aspirates were scored according to the cytologic grading system, devised by Masood et al. and based on six cytologic criteria. Concordance rates between cytomorpholgic diagnosis and cytologic diagnosis using the cytologic criteria grading system and histologic diagnosis were 88% and 92%, respectively.

Thirty cases of Kikuchi's lymphadenitis, diagnosed by fine needle aspiration cytology, were reviewed to determine the main cytologic features helpful in reaching a diagnosis. The patients(mean age 26.6 years, male: female = 1:3.8) presented with lymphadenopathy (cervical 24, submandibular 3, and axillary 1) with or without fever and local tenderness. Excisional biopsy was done for confirmation in 5 cases and the remaining 25 cases showed the similar cytologic and clinical features. In the aspiration smears of all cases, there was a heterogenous celluar mixture including frequent extracellular karyorrhectic nuclear debris, phagocytic histiocytes, plasmacytoid monocytes, and a variable number of polymorphous lymphocytes such as immunoblasts, activated large lymphocytes, and small mature lymphocytes. The characteristic cytologic features of Kikuchi's lymphadenitis were the following: (1) frequent extracelluar karyorrhectic nuclear debris in the background : (2) phagocytic histiocytes with eccentrically placed crescentic nuclei and abundant pale cytoplasm containing phagocytized karyorrhectic debris : (3) plasmacytoid monocytes, which were medium-sized cells with eccentrically placed round nuclei and amphophilic cytoplasm : (4) no neutrophilic background.

Fine needle aspiration biopsy cytology is a widely recognized and useful technique which can provide diagnosis in lesions of the head and neck, enabling appropriate management plans for individual patient to be made. Fifty one fine needle aspirates from salivary gland masses were examined. Four aspirates (8%) were inadequate for examination. Of the remaning 47 samples, 42 cases (82%) were benign lesions which consist of 30 pleomorphic adenoma(58%), 7 inflammatory lesion (14%), 4 Warthin's tumor(8%) and 1 benign lesion(2%). Two cases(4%) were atypical lesions. Three cases(6%) were malignant lesions consisting of 2 adenoid cystic carcinomas(4%) and 1 mucoepidermoid carcinoma (2%). The cytologic diagnoses were compared with the subsequent histologic diagnosis of surgical resected specimen in 24 cases. 19 cases of 21 aspirates from benign tumors were correctly diagnosed by fine needle aspiration cytology, with a specificity of 90%. All 3 aspirates from the 3 patients with malignant tumor were correctly diagnosed by fine needle aspiration cytology, with a sensitivity at 100%. Overall acurracy was 88%. Diagnostic error was encountered in adenoid cystic carcinoma, mucoepidermoid carcinoma and Warthin's tumor Correct histologic diagnosis was made in 86% of benign tumors(84% for pleomorphic adenoma and 100% for Warthin's tumor) and in 100% of malignant tumors.

Urinary cytology is increasingly accepted as a diagnostic tool in the detection and follow-up of patients with bladder cancer. However, its value is reduced by several limitations, especially by the lack of cytologic criteria specifically reflecting the morphology of low-grade urothelial neoplasm. We reviewed histologically proven 50 cases of urine cytology with emphasis on cytologic findings of benign atypia and differential findings of urothelial neoplasm according to the grade. The diagnoses included 17 benign lesions(including 5 cases of urine calculi) and 33 malignant lesions (including 28 transitional cell carcinomas, 3 squamous cell carcinomas, 1 adenocarcinoma and 1 prostate adenocarcinoma), Diagnostic accuracy was 92%. Important cytodiagnostic criteria for benign atypia and low grade malignancy were cellularity, number of cell clusters, and morphology and arrangement of urothelial cells. The cytologic findings of urothelial neoplasms according to histologic grade were relatively well correlated with the histologic findings. However, the cytologic criteria were not sufficient to readily distinguish grade I from grade II. In view of this, we think that cytologic nomenclature "low-grade" and "high-grade" is a more reliable criterion. Recognition of subtle cellular morphologic features specific for urothelial lesions(including benign or malignancy) and proper fixation, processing and staining of specimen can expand the role of urinary cytology In detection and follow-up of patients.

Urine cytology is of limited value in the diagnosis of renal cell carcinoma with reported detection rates of $0\sim80%$. The aim of this study is to demonstrate the usefulness of urine cytology in renal cell carcinoma. In the eleven histologically proven cases of renal cell carcinoma, urinary smears were reevaluated. The cytologic results were as follows; positive for malignant cells in 3 cases(27%), suspicious in 2 cases(18%) and negative in 6 cases(55%). The average diameter of the tumor of the 5 cases reported as positive or suspicious for malignant cells was 9.7cm and 3 had invaded the renal pelvis. The other 6 tumors, reported as negative, were 5.7 cm in average diameter and one of them showed involvement of the renal pelvis. These results suggest that urine cytology is considered unsatisfactory in the early defection of renal cell carcinoma. However, careful examination of urinary smear could improve the detection rate especially in more advanced cases involving the renal pelvis as well as those of larger tumors.

Fine needle aspiration cytologic findings in 14 cases of gynecomastia are described. General cytomorphologic features resemble those of fibrocystic disease in women than those of fibroadenoma. Among the cytologic parameters, three-dimensional structure of epithelial cell clusters, presence of micronucleoli and irregularities of nuclear size and shape are suggestive of epithelial proliferative activity. In audition, 4 cases are proliferative breast disease without atypia and 10 cases are nonproliferative breast disease depending on cytologic criteria grading system.

A prospective survey of sputum cytologic specimen was performed for 16 months from Jan. 1993 to Apr. 1994 in Presbyterian Medical Center. The purpose of this study is to find the positive rate of sputum cytology in the diagnosis of lung cancer and to correlate these results with tumor location and stage. Sputum cytologic specimen were received from 104 patients among 158 patients diagnosed as lung malignancy by histologic examination. Cytologic diagnosis of "suggestive of malignancy" was made in 61 patients (59%) and dysplasia in 9 patients(9%), atypia in 14 patients(13%), benign in 15 patients(14%) and inadequate specimen in 5 patients (5%), respectively. Among 84 patients beyond the cytologic diagnosis of atypia, 51 patients (61%) disclosed a central location, while 33 patients (39%) showed peripheral lesions. All 54 patients diagnosed as suggestive of non-small cell carcinoma were stage III or over, and all 7 patients diagnosed as suggestive of small cell carcinoma were in advanced stage. These results suggest that the cytologic examination of sputum seems to be an important tool in diagnosis of lung cancer.

Pulmonary giant cell carcinoma is one of the most highly malignant neoplasms of the lung. Although mixed malignant glandular or squamous components may be associated with a giant cell carcinoma, it is a distinct clinical and morphologic entity. We reviewed cytologic presentations of 6 cases of pulmonary giant ceil carcinoma. Cytologically, the single most characteristic feature of giant cell carcinoma was an extremely large, bizarre cancer cell engulfing numerous leukocytes. The nuclei of these cells showed occasional prominent nucleoli, and the cytoplasm was abundant. Giant cells were also seen in other types of pulmonary carcinoma, but the slant cells of this neoplasm could be differentiated from those encountered in undifferentiated large cell carcinoma and squamous cell carcinoma by the abundant cytoplasm, the presence of markedly enlarged nuclei, prominent nucleoli, and a significant degree of phagocytosis. In conclusion, precise diagnosis and classification of lung cancer is imperative because of proved correlation between cell type and prognosis.

Collecting duct carcinoma of the kidney is an unusual variety of renal carcinoma considered to arise from the epithelium of the collecting ducts. We recently experienced a case of fine needle aspiration cytology of collecting duct carcinoma of the kidney in a 17 year-old girl. The smear revealed many cellular clusters of ordinary papillary pattern, characterized by clumping of cells with nuclear overlapping, in a slightly necrotic background. The tumor cells had abundant delicate granular cytoplasm with some having vacuolation. The nuclei were only slightly pleomorphic with somewhat coarse chromatin and one or more small nucleoli Some nuclei showed irregular nuclear membrane and nuclear groove. A few polymorphs were also present.

Small cell carcinoma of the urinary bladder is a rare tumor which occurs in about 0.48 % of all bladder tumors. We report cytologic features of small cell carcinoma of the urinary bladder in a 66-year-old man who had painless total gross hematuria, which was confirmed by partial cystectomy. In urine cytology, abundant tumor cells appeared in scattered and clustered forms in a bloody background. The tumor cells were small and uniform in size with a high nuclear/cytoplasmic ratio. The nuclei of the tumor cells were hyperchromatic, characteristically molded and showed inconspicuous nucleoli. The cytoplasms were scanty and pale blue.

Anaplastic carcinoma of the thyroid is one of the most malignant tumors and survival for longer than three years after diagnosis is exceptional. Multinucleated giant cells of osteoclastlike appearance are seen un some of the anaplastic carcinoma, but only three cases in which the diagnosis was made by fine needle aspiration (FNA) cytology are reported in the international literature. We experienced a case of anaplastic carcinoma with osteoclastlike giant cells in a 66-yr-old female, diagnosed by FNA cytology. The smears revealed two cell populations: multinucleated giant cells and large polygonal or spindle shaped malignant cells. The FNA cytodiagnosis of anaplastic thyroid carcinoma containing osteoclastlike giant cells was substantiated by subsequent biopsy.

Orbital meningioma is a rare neoplasm that, even when suspected by CT or echographic examination, requires careful histologic study for precise identification. Fine needle aspiration(FNA) biopsy has become the diagnostic technique of choice in recent years for investigating orbital masses. There have been a few previous reports on FNA biopsy of orbital menigioma. We experienced a case of orbital meningioma in a 11-yr-old boy, diagnosed by FNA biopsy. The cytohistologic features of aspirated material (intranuclear inclusions, psammoma bodies, and cells arranged in whorls) made it easy to diagnose a meningloma.

A case of metastatic mucoepidermoid carcinoma of the lung, originating from the hard palate, was diagnosed by sputum and bronchial washing cytology. Although the cytologic features of mucoepidermoid carcinoma have been well described, it is easy to confuse mucoepidermoid carcinoma with the more common primary adenocarcinoma or squamous cell carcinoma of the lung. The features distinguishing mucoepidermoid carcinoma from other primary neoplasms include 1) mucus-secreting cells individually and in clusters admixed with other cell components, 2) epidermoid cells identified by the presence of abundant spread-out cytoplasm and an oval dark nucleus and 3) intermediate cells resembling normal ductal epithelial cells with moderate-to-scanty cytoplasm, a central, round vesicular nucleus and a prominent nucleolus. The morphologic features of metastatic mucoepidermoid carcinoma in this case were similar to those of primary salivary mucoepidermoid carcinoma.

Therapeutic management of brain tumors is based on accurate knowledge of their size, location and histologic type. Stereotaxic cytology under CT guidance has been applied to the investigation of brain tumors, especially in the sellar turcica, third ventricle, and pineal regions. In the present case, the tumor protruded into the nasal cavity, so we were able to get cytologic material via fine needle aspiration. Although pituitary adenoma is not an unsual tumor, there have been few reports about its cytologic features. We present the cyotologic and histologic features of a case of pituitary adenoma with immunohistochemical study.

Malignant thymoma is usually manifested as a mediastinal mass. Occasiomally, these tumors may be associated with a variety of systemic syndromes, such as myasthenia gravis, pure red cell aplasia or hypogammaglobulinemia However, it is generally accepted that thymomas rarely metastasize and the frequency of extrathoracic metastasis has been reported as 1 to 15%. In general, nuclear changes of tumor cells such as enlarged size, irregular shape and altered textures are determining factors in the assessment of the grade of malignancy. We experienced a case of malignant thymoma of anterior mediastinum in a 35-year-old woman. After 3 years, she developed recurrent malignant thymoma in the right supraclavicular area, diagnosed by aspiration biopsy cytology.