Aspiration cytology of breast cysts.

A cytologic evaluation was made of 57 samples of fluid aspirated from cystic breast masses during the past 12 years in our hospital. The cytologic diagnosis of the cyst aspirates from 17 cancer cases was positive in 10 cases, suspicious in 2 and negative in 5. No false-positive cytologic diagnosis was made in 40 cases of benign cystic disease. Blood-tinged aspirates were observed in 14 of the 17 cases of malignant cystic disease but in only 2 of 40 benign cases. Ductal cell clusters were detected in aspiration smears from 16 of the cases of malignant cystic disease and 15 of the cases of benign cystic disease. Apocrine cells were seen in the aspiration smears from 12 of the cases of benign cystic disease but in none of the aspirates from the 17 cancer cases.