Value of P-glycoprotein, glutathione S-transferase pi, c-erbB-2, and p53 as prognostic factors in ovarian carcinomas.

Abstract

PURPOSE To determine the prognostic value of immunostaining of P-glycoprotein (P-gp), glutathione S-transferase (GST) pi, c-erbB-2, and p53 in patients with advanced-stage ovarian carcinoma. PATIENTS AND METHODS Immunostaining of P-gp, GST pi, c-erbB-2, and p53 was performed on 89 primary tumors and 38 residual tumors after chemotherapy (P-gp and GST pi) in patients with advanced ovarian carcinoma treated with platinum- and doxorubicin-containing chemotherapy. The results of immunostaining were related to clinicopathologic prognostic factors, response to chemotherapy, and progression-free survival (PFS) and overall survival. RESULTS P-gp and GST pi immunoreactivity were present in 13 (15%) and 79 cases (89%), respectively, and were not associated with any other prognostic factor or PFS or overall survival. C-erbB-2 immunoreactivity was present in 18 cases (20%) and was associated with undifferentiated histiotype (P < .05), but not with PFS or overall survival. p53 immunoreactivity was present in the nuclei of 31 cases (35%) and cytoplasm of nine cases (10%). Nuclear p53 staining was associated with grade III tumors, presence of more than 1-L ascites, and residual tumor after first laparotomy more than 2 cm. Nuclear p53 staining was associated with shorter PFS (relative risk [RR], 3.3; 95% confidence interval [CI], 2.0 to 5.6) and overall survival (RR, 2.6; 95% CI, 1.7 to 3.8). After adjustment for presence of more than 1-L ascites or age more than 50 years, nuclear p53 staining did not retain independent prognostic significance in stage III/IV tumors. The frequency of P-gp staining in residual tumors after chemotherapy (18 of 38 cases) was higher in comparison to untreated tumors (13 of 89 cases) (P < .001). No combination of prognostic parameters was able to predict response to chemotherapy adequately. CONCLUSION Nuclear immunoreactivity of p53 in ovarian carcinomas is associated with shorter PFS and overall survival and determinants of more aggressive tumor growth. The higher frequency of P-gp immunoreactivity in residual tumors after chemotherapy points to induction of P-gp in ovarian carcinomas by doxorubicin-containing combination chemotherapy. The determination of P-gp, GST pi, c-erbB-2, and p53 does not permit more adequate prediction of response to chemotherapy.