DNA Ploidy Heterogeneity in Primary an Metastatic Lesion of Epithelial Ovarian Cancer

Kim, Jong Hyeok; Nam, Joo Hyun; Huh, Joo Ryung; Kim, Yong Man; Kim, Young Tak; Mok, Jung Eun

Abstract

Tumor DNA content measured by flow cytometry may be a predictor in the prognosis of epithelial ovarian cancer, but the results have been inconsistent. It is recognized that these conflicting results are at least partly due to the variation of DNA content between the samples from the same patient(i.e., intratumoral DNA heterogeneity). The purposes of this retrospective study were to investigate the frequency and the nature of DNA heterogeneity in epithelial ovarian cancer and to evaluate the prognostic significance of DNA heterogenetiy itself. Thirty-two patients with stage II to IV epithelial ovarian cancer who were managed at Asan Medical Center between May 1993 and April 1996 were analysed. Measurements of the nuclear DNA content were performed on samples from primary and metastatic lesion using paraffin embedded archival tissues by Epics(Coulter Inc.) flow cytometry. In two cases, the metastatic tumor was minute and did not reveal a separable peak on repeated examination. DNA heterogeneity was defined as different ploidy pattern or difference of the DNA indices than 0.15 between primary and metastatic tumors. DNA heterogeneity was found in 11 cases(36.7%), and the number of cases with homogeneous diploid and that with homogeneous aneuploid tumor were 5(16.7%) and 14(46.7%) respectively. In evaluation of prognostic significance of DNA heterogeneity using correlation with serum CA 125 level after second course of chemotherapy and residual tumor size after cytoreductive surgery among these three groups, the patients with DNA heterogeneity were considered to show intermediate prognosis between those with homogeneous diploid and homogeneous aneuploid tumor. In conclusion, DNA heterogeneity in epithelial ovarian cancer is considerable in frequency and may have prognostic value.