Peritoneal fluid analysis in the differentiation of ovarian cancer and benign ovarian tumor.

PURPOSE The aim of the study was to try to identify the biochemical markers in peritoneal fluid which might be useful in discrimination between ovarian cancer and benign ovarian tumor. METHODS The study included 75 patients: 43 with invasive ovarian cancer, 6 with borderline ovarian cancer and 26 with benign ovarian tumor. The peritoneal fluid samples from all these patients were subjected to cytologic examination and to analysis of lactate dehydrogenase (LDH), total protein, albumin and cholesterol. In addition, peritoneal fluid to serum ratio of LDH and total protein, as well as serum CA-125 were assayed. The biochemical parameters were compared between cases of ovarian cancer and cases of benign ovarian tumor, as well as between the different histological types and stages of ovarian cancer. RESULTS All the examined parameters demonstrated a significant difference comparing patients with ovarian cancer and those with benign ovarian tumor (p<0.001). Yet, the greatest diagnostic accuracy was achieved by measuring peritoneal fluid LDH (86%) and cholesterol (93%). Moreover, significant differences in the level of assayed parameters were found when comparing different histological types and stages of ovarian cancer. In order to further corroborate the diagnostic performance, we combined the parameters of LDH and cholesterol with cytology, thus increasing the diagnostic accuracy to 96%. CONCLUSION The association of peritoneal fluid LDH and cholesterol may represent a primary tool for the discrimination of patients with ovarian cancer (even borderline) from those with benign ovarian tumor, particularly in the presence of negative cytology.