Limited prognostic value of tissue protein expression levels of BCl-2 in Danish ovarian cancer patients: from the Danish 'MALOVA' ovarian cancer study

The purpose of the study was to determine the expression of BCl-2 in epithelial ovarian tumors and to correlate expression levels with selected clinicopathologic parameters, time to progression and prognosis of the disease. Using tissue arrays (TA), we analyzed BCl-2 expression in tissues from 191 women diagnosed with low malignant potential ovarian tumors (LMP) and from 582 patients diagnosed with ovarian cancer (OC). Using 30% as cutoff level for BCl-2 overexpression, 5% of LMPs were positive with a higher proportion of serous ovarian tumor of LMP, compared to mucinous ovarian tumor of LMP (p = 0.02). Women with a BCl-2-positive LMP tumor were older than women with a BCl-2 negative tumor (p = 0.02). Ten percent of OCs were positive for BCl-2 expression (>or=30%). No significant association was found between BCl-2 expression levels and histologic type of tumors (serous vs mucinous, p = 0.19). A 30% cutoff value or a percentage scale showed that BCl-2 expression had no prognostic value, both in univariate and in multivariate survival analyses. No difference in time to progression was observed between patients with BCl-2-positive and negative tumors. These data suggest that BCl-2 expression may not be of important clinical value in the treatment of Danish OC patients.