Differentiated DNA analysis in relation to steroid receptor status, grading, and staging in human breast cancer.

Flow cytometric DNA analysis was performed in 100 cases of human breast cancer. Using a category system of six ploidy groups, ploidy status was distributed as follows: The majority of the neoplasias were either diploid (45%), hyperdiploid (21%), or tetraploid (15%), whereas the remaining marginal ploidy groups, i.e. hypodiploid (4%), hypertetraploid (9%), and multiploid (6%) were less frequent. In an attempt to evaluate the prognostic significance of DNA content, ploidy status was correlated with steroid hormone receptor status, histopathological grade, and TNM data. The higher incidence of negative estrogen and progestin receptor status and higher histopathological grade in hyperdiploid malignancies was significantly different from the prognostically more favorable positive receptor status and lower grade in diploid tumors. Tetraploid neoplasias statistically resembled the latter group with respect to both parameters. As far as TNM data are concerned, tendencies towards less favorable staging were observed in hyperdiploid as compared to diploid and tetraploid tumors. A definite statement of the prognostic significance of the marginal ploidy groups cannot be made at present. In order to characterize diploid malignancies more closely, proliferative activity expressed by %S-phase was analyzed. Steroid receptor status of diploid tumors exhibiting more than 6% S-phase did not differ statistically from that of hyperdiploid neoplasias. In contrast, diploid tumors expressing less than 6% S-phase closely resembled tetraploid ones. Our data emphasize the prognostic significance of differentiated DNA analysis.