The relation of prognosis to the nuclear diameter of breast cancer cells obtained by cytologic aspiration.

Nuclear diameters of breast cancer cells obtained by aspiration cytology from 245 patients were measured by ocular micrometry. The nuclei of 50 benign lesions were also measured. Cancers with 80% or more of their nuclei larger than 12 mu were classified as "large nuclear type" (LN). Those with nuclei of 12 mu or less were considered "small nuclear type" (SN). One hundred forty-nine cases of the former and 96 of the latter were evaluated. There was significant overlap in nuclear diameter of benign lesions and SN cancers but minimal overlap between SN and LN cancers. Thirty-eight percent of SN cancers were staged as T1 as compared to only 20% of LN tumors. Survival, free of disease, at five years was 90% for the SN cancers and 58% for the LN cancers (p less than 0.001). Intervals between completion of treatment, appearance of metastases and death were longer for patients with SN cancers. Measurement of nuclear diameters of cells obtained by aspiration cytology may, therefore, be useful in determining the prognosis.