Fine-needle cytology of the breast: a controlled study of aspiration versus nonaspiration.

We report on 534 breast masses examined by fine-needle aspiration cytology. Two samples were obtained from each mass, one with aspiration and the other without. Aspiration, equivalent to that obtained by a 20-ml syringe on full aspiration, was obtained by an automatic aspirator. The two sampling modalities did not differ apart from aspiration and were compared in terms of inadequate sampling rates. The inadequacy rate was the same in 166 cancers (6.6%), whereas a significant difference was recorded in favor of aspiration (13.6 versus 24.4%) in 368 benign masses. When inadequate results were excluded, the accuracy of the two modalities was almost the same. Sensitivity was 97.4% and 96.7% and specificity was 99.4% and 99.3% for sampling with and without aspiration, respectively. Reducing the rate of inadequate sampling from benign masses seems to be the major advantage of aspiration. Double sampling, independent of the specific techniques, reduced inadequacy rates to very low levels (1.2% for cancers; 5.9% for benign masses) and may be useful as a routine policy.