Diagnostic Usefulness of Fine Needle Aspiration Cytology on Lymphadenopathy

림프절종대의 세침흡인 세포검사의 진단적 유용성 - 림프절의 세침흡인 세포검사 1,216예의 분석 -

Clinical lymphadenopathies are subjected to fine needle aspiration cytology(FNAC) for diagnosing not only benign lesions but also malignant ones, as the first diagnostic procedure. While the diagnostic reliability in metastatic carcinoma is high, it is difficult to differentiate malignant lymphoma from reactive conditions. We evaluated the diagnostic reliability of FNAC in lymphadenopathy, and discuss the diagnostic limitation and its place in clinical practice in this study, Over 8 years from January 1988, FNAC of 1,216 lymphadenopathies were analyzed and among them 170 cases were compared with histopathology. The results are as follows. 1. Of ail the cases, 890 cases(73.2%) were diagnosed cytologically as benign, 312 cases(25.7%) as malignant, and 14 cases(1.1%) as unsatisfactory material. Reactive hyperplasia was diagnosed in 585 cases(65.7%) of the benign lesions, and among the malignant diseases, metastatic carcinoma was diagnosed in 248 cases(79.5%), and malignant lymphoma in 62 cases(19.9%). 2. The overall diagnostic accuracy was 89.2%, and no false positive case and 9 false negative results were observed among 170 cases which were proven by histopathology. Six cases of sampling error of false negative diagnoses included 3 of metastatic carcinomas and 3 of malignant lymphomas. The causes were difference between aspiration and biopsy site, poor fixation, or scanty cellularity with bloody smear. All 3 cases of misinterpretation error were malignant lympliomas, one of mixed type on biopsy which was diagnosed as reactive hyperplasia cytologically. In summary, FNAC technique is thought to be useful in the initial diagnosis of lymphadenopathies as well as in the follow-up of patients with known malignancy. Although the results of malignant lymphoma was less accurate than other malignant lesions, the application of strict cytologic criteria or lymphoid marker studies of aspiration material will reduce the false negative rate.