Utility of fine-needle aspiration in the diagnosis of granulomatous lesions of the breast.

Fourteen cases of granulomatous mastitis (GM) studied by fine-needle aspiration (FNA) are reviewed and nine cytologic features (necrosis, neutrophil granulocytes, foamy cells, plasma cells, granulomas, epitheloid cells, multinucleated giant cells of foreign body type and Langhans' type, duct cells, and the presence of acid-fast bacilli) are reappraised in a semiquantitative manner. The main objective of this study was to find out if one or more of these features would permit the various granulomatous entities identified in surgical pathology to be separated cytologically. The results suggest that FNA does not permit the various granulomatous lesions identified in surgical pathology to be differentiated, since in this series different entities share a common cytologic pattern. Only the presence of acid fast bacilli in smears would enable a tuberculous etiology to be diagnosed. The opinion is put forward that the term GM should be avoided in the cytologic report and substituted by the noncommitted term "granulomatous lesion of the breast.