Inflammatory lesions of the breast: diagnosis by fine needle aspiration.

Amongst 1061 breast lesions diagnosed by fine needle aspiration (FNA) over a period of 6 years (1985-1990), 128 were reported to be showing changes consistent with an inflammatory lesion. On review, the cytodiagnosis was found to be inaccurate in 31 cases. The cytological features of the 97 cases that were correctly reported are described in this report. The cytological diagnoses issued in these 97 cases were acute mastitis or breast abscess (57 cases) and tuberculous mastitis (30 cases). Non-specific chronic mastitis and miscellaneous conditions accounted for four and six cases respectively. Acid fast bacilli (AFB) were demonstrated in 28.0% of tuberculous mastitis cases and 10.0% of those diagnosed as acute mastitis or breast abscess. FNA cytology was found to be useful for the diagnosis of inflammatory lesions of breast and their classification, as only five out of 57 cases of acute mastitis/breast abscess and one out of 30 tuberculous mastitis cases were suspected on clinical grounds.