Multivariate analysis for prognostic significance of histologic subtype, GST‐pi, MDR‐1, and p53 in stages II‐IV ovarian cancer

. It has been suggested that histologic subtype of ovarian cancer is a factor that determines the chemoresponsiveness of tumor. In this study, we wanted to clarify the prognostic significance of histologic subtype and its correlation to expression of chemoresistance‐related proteins (CRPs) in ovarian cancer. A total of 93 stage II‐IV ovarian cancers, where the proportion of serous, endometrioid, mucinous, and clear cell subtype was 61.3%, 14.0%, 7.5%, and 17.2%, respectively, were investigated for glutathione S‐transferase‐pi (GST‐pi), MDR (multidrug resistance)‐1, and p53 expression using immunohistochemistry. GST‐pi expression was detected in 62.4% of the tumors and was not related to histologic subtype of tumor. MDR‐1 expression was observed in 12.9% of the tumors tested and was more frequently detected in clear cell adenocarcinomas than other histologic subtypes of tumor (10/ 16 vs. 2 / 77, P