Correlation of DNA flow cytometric results and other prognostic factors in primary breast cancer.

The percentage of cells in S-phase and DNA-ploidy have been measured in 300 primary mammary carcinomas by means of DNA-flow cytometry (FCM). The data were compared with the age and menopausal status of the patients as well as with the size, regional lymph-node involvement, histologic type, grade and concentration of estrogen (ER) and progesterone (PR) receptors of the tumors. A DNA-diploid distribution of the G0/1-peak was found in 37.6% of the cases. The mean percentage of S-phase fractions was 4.83. DNA-aneuploid tumors had significantly higher amounts of S-phase fractions (6.12%) than DNA-diploid tumors (2.66%). There was also a significant correlation between the DNA measurement data (DNA-ploidy and S-phase fractions) and histologic grade, as well as the content of ER and PR, but not between DNA-ploidy, S-phase fractions, tumor size (T) and evidence of axillary lymph-node metastases. DNA-FCM gives a biological characterization of the tumor in addition to the histopathologic examination. The method can be used as a routine procedure because of the reliability and reproducibility of the results as well as the short time needed for the measurements.