Since 1950s, fine needle aspiration(FNA) cytology has become increasingly popular and numerous reports have demonstrate its accuracy, safety and cost-effectiveness. To evaluate the role of diagnostic FNA cytology in the thyroid nodule, authors compared preoperative cytologic findings with postoperative histologic diagnosis in two hundred two thyroid nodules underwent surgical resection at Department of Surgery, Pusan Paik Hospital. from July 1990 to December 1993. FNA and thyroidectomy was performed primarily by one Head and Neck surgeon and specimen was interpreted by several pathologists. One hundred seventy two FNAs(85%) were interpreted as positive for benign lesion or carcinoma and thirty(15%, cystic in 25, non-cystic lesion in 5 cases) were unsatisfactory specimens for interpretation. The preoperative cytologic diagnosis of 172 cases revealed 'benign' in 112. 'suspicious cancer' in 10 and 'cancer' in 50 cases. Postoperative pathologic diagnosis showed 'nodular goiter' in 64. 'benign tumor' in 43, 'thyroiditis' in 4 and 'cancer' in 61 cases. The value of preoperative FNA diagnosis for thyroid cancer yielded a sensitivity of 85.2%, a specificity of 92.7%, false negative rate 5.2%, false positive rate 4.5% and positive predictive value and overall accuracy were 86.6% and 90.1% respectively. Preoperative rate of malignancy could be increased up to 35.5% by using FNA.
Bile duct brush cytology has been employed as a diagnostic tool for the evaluation of pancreatic and biliary tract strictures. The specificity of this method is high however, its sensitivity is quite low. A recent study employing liquid based cytology (LBC) reported results comparable to those achieved via conventional cytology. Therefore, we have attempted to prospectively evaluate the diagnostic utility of bile duct brush cytology in pancreaticobiliary diseases. A total of 46 cases with bile duct stricture were enrolled including 11 cases of benign stricture, 29 cases of bile duct carcinoma, 3 cases of gallbladder cancer, and 3 cases of pancreatic cancer. Both conventional smear and LBC using $MonoPrep2^{TM}$ system were conducted in each case. The cytological diagnosis of each case was classed into the following categories; benign, suspicious for malignancy, and malignancy. The diagnostic accuracy of both cytologic methods was investigated. LBC evidenced a high rate of material insufficiency (13/46), which was attributed to low cellularity. The kappa index of both cytological methods was 0.508. Cytological and tissue diagnoses were correlated in 25 cases conducted from biopsy or operation. The sensitivity, specificity, positive predictive value, and negative predictive value were 41.2% (7/17), 100% (8/8), 100% (7/7), and 44.4% (10/18) in conventional smear; 58.8% (10/17), 87.5% (7/8), 90.9% (10/11), and 50.0% (7/14) in LBC; and 94.1% (16/17), 87.5% (7/8), 94.1% (16/17), and 87.5% (7/8) in any one of both cytological methods, respectively. Based on these results, the sensitivity of LBC was found to be superior to that of conventional smear and we were able to obtain higher positive predictive value upto 94.1% by simultaneously conducting both cytologic methods.
Purpose: The purpose of the study was to evaluate the sensitivity, specificity and accuracy between the FNAC and intraopevative frozen biopsy based upon the Final histologic diagnosis. Method: Authors studied 232 cases of thyroid nodule operated at Department of Surgery, College of Medicine, Chosun University, from January 1992 to December 1998. The medical records of these patients were studied retrospectively. The cytology of FNAC and the frozen section was compared to the final histologic diagnosis. 232 cases were analysed in regard to correlation of FNAC diagnosis and Intraoperative frozen section with final pathology, preoperative thyroid scan, thyroid function test, ultrasonography, final histopathology of the specimens, and surgical operation methods. 174 cases who underwent FNAC for diagnosis before operation, and Intraoperative frozen-section biopsy were classified according to whether the clinical diagnosis was benign, suspicious or malignant and evaluated the specificity sensitivity and accuracy. Result: Comparing with final histopathology, FNAC as a diagnostic test for thyroid nodules demonstrated an accuracy of 81.3%, a sensitivity of 87.5%, a specificity 86.5% with a false positivity of 2.9%, false negativity of 4.3%, respectively. and Intra-operative frozen section demonstrated an accuracy of 86.8%, a sensitivity of 87.5%, a specificity 92.1%. In the benign lesion, there was no difference in accuracy between FNAC(95.6%) and frozen section(95.1%) but, in the suspicious malignant lesion, frozen section(46.2%) was superior to FNAC(32.0%), and in the malignant disease, FNAC(97.1%) was superior to frozen section(92.3%). Conclusion: Intraoperative frozen section biopsy is useful in patients undergoing surgery for a thyroid nodule with a 'suspicious' malignant lesion and could reduce inadequate extensive excision without missing malignancy and second operation and help to determine the resection margin. It adds no information in patients with a diagnosis of malignancy following FNAC assessment and is of limited use in those in whom a benign lesion is diagnosed.
Fine needle aspiration cytology(FNAC) is preferred because of simplicity, safety, and reliability in the evaluation of patients with thyroid nodule or hyperplasia. However, there are a few limitations such as false-negative or false-positive cases and non-diagnostic material. To evaluate the usefulness of FNAC in thyroid lesions, we reviewed 704 FNAC cases of thyroid nodules from 1988 to 1994 at Soonchunhyang University Hospital. The results are as follows. 1. Among 704 FNAC cases of thyroid gland, 571(81.1%) cases were benign, 12(1.7%) were suspicious, 71(10.1%) were malignancy, and 50(7.1%) were material insufficiency. The cytologic diagnoses of the benign lesions included 168 cases of follicular neoplasm, 139 cases of adenomatous goiter, 162 cases of follicular lesion such as follicular neoplasm or adenomatous goiter, 61 cases of Hashimoto's thyroiditis, 13 cases of subacute thyroiditis, and 28 cases of colloidal nodule or benign nodule. The malignant lesions included 68 cases of papillary carcinona, two medullary carcinomas and a case of metastatic colon cancer. 2. The average number of cytologic smear slides was $4.12{\pm}1.81$ in material insufficiency and $5.63{\pm}1.79$ in diagnostic cases. This difference was statistically significant(p<0.00001). 3. Histological assessment of 150 cases revealed 2 false negative and 1 false positive cases. The false negative cases were a case of marked sclerosis in papillary carcinoma and an occult case of papillary carcinoma. The false positive case resulted from pseudo-ground glass nuclei due to marked dry artifact. 4. Comparison between the FNAC and the histologic diagnosis revealed that FNAC had a sensitivity of 93.5%, a specificity of 99.2%, a false negative rate of 6.6%, a false positive rate of 0.8%, and an overall diagnostic accuracy of 98.0%. Therefore, FNAC of thyroid gland is a very reliable diagnostic method with excellent accuracy rate.
This is a retrospective review of fine-needle aspiration cytology(FNAC) smears of 153 cases of thyroid disease performed during August 1989 to July 1995, which were confirmed histologically following surgical operations. FNAC results showed 63 cases(41.2%) of adenomatous goiter, 45 cases(29.4%) of papillary carcinoma, 29 cases(19.0%) of follicular neoplasm, 4 cases(2.6%) of follicular variant of papillary carcinoma, 4 cases(2.6%) of Hashimoto's thyroiditis, 4 cases(2.6%) of $H\ddot{u}rthle$ cell neoplasm, 2 cases(1.3%) of medullary carcinoma and one case(0.7%) each of subacute thyroiditis and of anaplastic carcinoma. The overall accuracy of cytological diagnosis was 83.7%. These data strongly suggest thyroid FNAC is a reliable preoperative diagnostic tool, but FNAC has been less valuable in the diagnosis of follicular lesions than any other disease of the thyroid. Adenomatous goiter was not infrequently interpreted as follicular neoplasia that requires surgery for diagnostic conformation and vice versa. The following findings are considered to be compatible with follicular neoplasm: 1) microfollicles, 2) nuclear grooving, 3) irregularity of nuclear membrane, and 4) irregular arrangement or crowding of follicular cells in groups. The FNAC criteria of adenomatous goiter are as follows: 1) atrophic follicular cells, 2) presence of macrophages, 3) abundant colloid, and 4) large follicles. It is recommended that aspiration of thyroid lesions in order to analyse with critical clinico-pathological approach and surgery is considered only for nodules that are clinically suspicious or unresponsive to hormone therapy or when a diagnosis of follicular neoplasm is made.
Kim, Duck-Hwan;Kim, Youn-Ju;Yang, Seung-Eun;Paeng, Sung-Suk;Chang, Hee-Jin;Sohn, Jin-Hee;Suh, Jung-Il
The Korean Journal of Cytopathology
/
v.6
no.1
/
pp.41-47
/
1995
Two hundred and twenty one consecutive patients with enlarged lymph nodes of the neck were diagnosed as metastatic carcinoma by fine needle aspiration. The metastatic carcinomas were most frequent in the supraclavicular lymph nodes (p<0.05). As a primary site, lung, stomach, upper respiratory tract and breast were commonly involved in descending order of frequency. Overall, squamous cell carcinoma was the most common in males (43%) while adenocarcinoma was the most common in females (72%) (p<0.05). While carcinomas of the esophago-gastro-intestinal tract showed a tendency to metastasize to the left supraclavicular lymph nodes, metastatic carcinomas of the lung and breast usually metastasized to the same side as that of the primary cancer with a predilection for the supraclavicular lymph nodes. The submandibular lymph nodes were frequently involved by carcinoma of the upper and lower respiratory tract, in which squamous cell carcinoma was the most prevalent cytologic type. Diagnosis by fine needle aspiration cytology is the first step in the workup of patients with nodal enlargement suspicious for malignancy, particularly in metastatic carcinoma.
Objectives: Fine needle aspiration cytology(FNAC) is a well established preoperative diagnostic procedure in the thyroid nodules. However, diagnostic accuracy of FNAC varies according to the size and the structural characteristics of thyroid nodule. We performed the ultrasound guided FNAC(US-guided FNAC) for impalpable thyroid nodule, and estimated the sampling accuracy rate through a comparison study between the cytologic diagnosis and the final histologic diagnosis of the postoperative specimens in order to determine clinical efficacy of the US-guided FNAC. Materials and Methods: We evaluated 117 patients underwent US-guided FNAC from January 1997 to December 1998. These patients had 129 thyroid nodules to need cytologic examination. Whereas the nodules were so no graphically classified into cystic, solid, and mixed type according to echo pattern, the aspirated thyroid specimens were classified into benign, malignant, suspicious, and insufficient. Results: Positive sampling for diagnositc examination was achieved in 75 nodules(58.1%), and US-guided FNAC in our study showed the accuracy rate of 95.2%, false positivity rate of 0%, and false negativity rate of 5.5%. Conclusions: US-guided FNAC is a powerful techniques for evaluating cytologic characterics and allowing a reliable diagnositc result in the impalpable thyroid nodule. However, the experienced technique is recommanded in order to obtain the sufficient samples for reliable results.
Carcinoma ex pleomorphic adenoma(CXPA) is a rare malignant tumor of the salivary gland, fine needle aspiration cytology(FNAC) of which are rarely reported. We retrospectively reviewed FNAC of five cases of histologically proven CXPA of the salivary glands diagnosed in Seoul National University Hospital to evaluate their cytologic characteristics. Histologically, the carcinoma components were low-grade in three cases and high-grade in two cases. The cytologic diagnosis were malignancy in two cases(40%), suspicious for malignancy in one(20%), and benign(pleomorphic adenoma) in two(40%). All of the high-grade carcinomas were correctly diagnosed by FNAC, however, 2 cases of low-grade carcinomas were diagnosed as benign by FNAC. The low sensitivity in cytologic diagnosis is due to interpretative difficulties in low-grade tumors. The characteristic cytologic features of CXPA were high cellularity, necrotic, bloody, and inflammatory background, marked nuclear overlapping, coarsely granular chromatin, prominent macronucleoli, and atypical mitosis in epithelial component in addition to the typical biphasic pattern of pleomorphic adenoma consisting of epithelial cells admired with spindle-shaped cells and chondromyxoid stroma. Even though low-grade tumors show mild pleomorphism, the cytologic findings of necrotic background, moderate to high cellularity, and nuclear overlapping could lead to an accurate cytodiagnosis of CXPA.
Cytologic evaluation of cerebrospinal fluid(CSF) is an effective tool in diagnosing many disorders involving the central nervous system(CNS). CSF examination has been found to be of particular value in the diagnosis of metastatic carcinoma, lymphomatous or leukemic involvement of CNS and certain primary CNS tumors. As a survey of metastatic tumors to CSF and an evaluation of the preparation techniques increasing cellular yield in our laboratory, 713 CSF specimens examined between July 1995 and April 1997(1 year 10 months), were reviewed. There were 75 positive and 5 suspicious cases, the latter have had no evidence of tumors clinically. Primary tumors of 75 positive cases were classified as follows; 4(5.3%) as primary brain tumors, 40(53.3%) as secondary carcinomas, 13(17.3%) as leukemias, and 18 (24.0%) as lymphomas. The most common primary site of metastatic carcinomas was the lung in 17 cases(42.5%) followed by the stomach in 13(32.5%), breast in 8 (20.0%), and unknown primary in 2(5.0%). Four primary brain tumors were 3 cerebellar medulloblastomas and a supratentorial primitive neuroectodermal tumor (PNET). All 40 metastatic carcinomas were adenocarcinoma presented as single cells or cell clusters. Although signet ring cells were frequent in the cases of gastric primary cancers, no significant cytologic differences according to the primary site were observed. The cytologic features of leukemia and lymphoma were characterized by hypercellular smears presenting as individual atypical cells with increased N/C ratio, presence of nucleoli, and nuclear protrusions. In medulloblastomas and PNET, the principal cytologic findings were small undifferentiated cells arranged singly or in loose clusters with occasional rosettoid features. This study suggests that the CSF cytology is useful in the diagnosis of malignancy, especially metastatic extracranial tumors and the diagnostic accuracy can be improved by increasing cellular yield using cytocentrifuge.
Park, In-Suh;Choi, Suk-Jin;Kim, Lucia;Han, Jee-Young;Kim, Joon-Mee;Park, Jung-Ae;Chu, Young-Chae
The Korean Journal of Cytopathology
/
v.18
no.1
/
pp.36-45
/
2007
Objective : To identify key cytologic features for diagnosis of adenocarcinoma and morphologic differentiation from reactive/reparative respiratory epithelium. Study Design : The cytomorphologic features of 145 pulmonary cytology specimens (sputum and bronchial washing), which included 117 histologically proven adenocarcinomas and 28 non-neoplastic lesions, cytologically diagnosed as atypia and suspicious for malignancy (adenocarcinoma) were reviewed retrospectively. We analyzed 11 morphologic criteria in pulmonary cytologic specimens. Results: Over 110 of 117 cases of adenocarcinomas revealed nuclear membrane irregularities, non-cohesive cells, single atypical cells, moderate to markedly enlarged nuclei and an increased nuclear/cytoplasmic (N/C) ratio. Chromatin clearing, chromatin heterogeneity and hyperchromasia were seen in 102, 99 and 97 cases, respectively. All 28 cases involving non-neoplastic lesions revealed hyperplastic reactive pneumocytes, hyperplastic reactive bronchial epithelium, or degenerating macrophages. The non-neoplastic lesions revealed a small number of atypical cell clusters and paucity or absence of atypical single cells. Conclusion : The most important morphologic features for diagnosis of adenocarcinoma are nuclear membrane irregularities, non-cohesive cells, single atypical cell, moderate to markedly enlarged nuclei and increased N/C ratio. Chromatin clearing, chromatin heterogeneity and hyperchromasia were also helpful features, while pleomorphism and prominent nucleoli were less valuable.
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