Clinical significance of abnormal nuclear DNA content in serous ovarian tumors.

The nuclear DNA content of 160 serous ovarian neoplasms was determined by flow cytometry from paraffin-embedded tissue. Three (11%) of the 27 histologically benign, seven (16%) of the 43 borderline malignant, and 59 (66%) of the 90 malignant neoplasms were aneuploid (P less than 0.0001). None of the patients with an aneuploid benign or borderline malignant tumor died from cancer, but in carcinomas the DNA index (DI) was a more important prognostic factor in a multivariate analysis than age at diagnosis, stage, histologic grade or ploidy (diploid versus aneuploid). A DI of 1.3 was the most effective value in predicting prognosis; patients with carcinoma with the DI more than 1.3 had inferior survival compared with those with the DI less than 1.3 (P = 0.002). Carcinomas with the DI more than 1.3 were more common in patients older than 60 years at diagnosis (P = 0.0002), and were associated with a low grade of differentiation (P = 0.008) but not with stage. It is concluded that DNA aneuploidy may occur in benign and borderline malignant serous ovarian tumors and that the DI is a highly valuable and objective prognostic parameter in serous ovarian carcinomas.