Abstract

Flow cytometric evaluation of cellular DNA-ploidy and S-phase fraction was undertaken in serial post-operative peritoneal washings in 43 patients with histologically proven ovarian carcinoma, and 20 control patients. Five patients had FIGO stage I, two stage II and the remainder stage III/IV disease. Daily sampling of peritoneal fluid was performed commencing at day 0 (operation day) until the seventh post-operative day. Samples were analyzed fresh using a flow cytometer. Aneuploidy was detected in 168 (62.5%) of samples. Three patients had persistent diploidy throughout the study period, and were excluded from analysis. The mean aneuploid count rose from 24.7% [SEM (standard error of mean) = 4.6] on day 0 to 43.6% (SEM = 5.7) on day 4 (P < 0.008). The S-phase fraction for the aneuploid populations fell significantly (P < 0.02) from 4.9% (SEM = 1.2) on day 0 to 2.2% (SEM = 0.8) on day 1, but subsequently continued to rise. Cytologic evaluation confirmed malignant cells in 79% of aneuploid samples. Three patients in the control population had similar patterns to malignant conditions, two of these patients having benign ovarian cysts and ascites. These findings show an increased proliferative activity of aneuploid malignant cells following surgical intervention, as detected in peritoneal lavage samples of patients with ovarian cancer.