Flow cytometric analysis for assessing the malignant potential of breast cancer.

Flow cytometric analysis was performed on 60 patients with breast cancer to investigate the relationship between DNA histogram and the malignant potential of breast cancer. DNA aneuploidy of breast cancer tended to increase with increasing stage and degree of nodal metastasis. The percent of cells in the S phase was significantly increased in the patients with metastasis compared to those without metastasis. Patients exhibiting percent S phase value of more than 20% showed a high frequency of metastasis even when breast tumors were small (T1, less than 2.0 cm in diameter). Thus, flow cytometric analysis may give additional information on biological characteristics and may be useful for predicting the prognosis of breast cancer in some patients.