Flow cytometrically determined DNA content of breast carcinoma and benign lesions: correlations with histopathological parameters.

The relative DNA content of cellular samples from 54 patients affected by breast carcinomas and 20 affected by benign breast lesions (including 11 fibroadenomas) was measured by flow cytometry. All normal tissue samples and 17/20 (85%) specimens from benign lesions exhibited a cytometrically diploid DNA distribution, 3/20 (15%) benign lesions an abnormal DNA content, and 35/54 (65%) carcinomas at least one aneuploid cell subpopulation. Furthermore, 9/54 (17%) tumors were characterized by the presence of more than one aneuploid cell subpopulation. The results also indicate that flow cytometry can be used to recognize lymph nodes infiltrated by aneuploid cells. Statistically significant correlations were evidenced between the occurrence of aneuploidy or the ploidy level measured as DNA index and the nodal infiltration status. The percentage of S cells can also be extracted from DNA content distribution histograms. Statistically significant differences (p less than 0.01) were also observed for the percentage of S cells between normal tissues (6.2 +/- 3.2 SD) and benign lesions (11.1 +/- 6.6 SD), normal tissues (6.2 +/- 3.2 SD) and aneuploid tumors (19.7 +/- 10.3 SD), benign lesions (11.1 +/- 6.6 SD) and aneuploid tumors (19.7 +/- 10.3 SD), and diploid (7.9 +/- 4.0 SD) and aneuploid tumors (19.7 +/- 10.3 SD).