The diagnosis of breast cancer by fine-needle aspiration smears.

Forty-eight percent of 93 breast carcinomas that were aspirated with a fine needle were found to be cytologically positive for carcinoma, and in another 31% this diagnosis was suspected. Care of most breast cancer patients with abnormal or questionable aspiration smears was affected by cytological diagnosis. Thirty-seven patients with a positive diagnosis for carcinoma and with consistent clincal findings were informed of the diagnosis prior to surgery and underwent modified radical mastectomies without further frozen-section examination. Twelve other patients with suspect or abnormal cytological reports had biopsies performed earlier because of these findings. A cytopathological diagnosis of carcinoma based on aspiration smears of the breast is highly accurate if strict criterions of malignancy are applied, but normal smears from solid breast masses do not exclude malignancy.