Lymph node aspiration biopsy. Diagnostic reliability and limitations--an analysis of 350 cases

The results of fine needle aspiration biopsy of lymph nodes in 350 patients and the modified biopsy technique used at our institution are discussed. Of the 350 cases, 209 aspirates were categorized as cytologically malignant, 102 as benign, 30 as suspicious for malignancy, and 9 as unsatisfactory. Cervical lymph nodes were most commonly sampled (58%), and supra-clavicular nodes were most likely to be malignant (90%). The overall diagnostic accuracy achieved was 94%. One false-positive and 9 (2%) false-negative results were observed in the 350 cases. In 3% of the 30 cases diagnosed as suspicious for malignancy, follow-up open biopsy of the lymph nodes in question proved them benign. The advantages and limitations of the procedure are discussed, as well as some of the possible sources of error, particularly in the diagnosis of lymphomas.