Objective: This study was undertaken to evaluate whether immunophenotyping of advanced epithelial ovarian cancer could predict response to initial chemotherapy and whether tumor immunophenotype changed after chemotherapy.
Study design: Fifty-four patients with stage III and IV ovarian cancer, treated at the University of Washington Medical Center, had pathology specimens evaluated. A subset of 23 patients also had specimens from a secondary surgery evaluated. Using immunocytochemistry, tumors were immunostained for overexpression of c-erb-B-2, epidermal growth factor receptor (EGFR), p53, and expression of the Ki67-defined antigen (a marker of cellular proliferation), tumor necrosis factor alpha (TNFalpha), estrogen receptor (ER), progesterone receptor (PR), and P-glycoprotein (P170, a marker of multidrug resistance). Twenty-four patients had a good response to chemotherapy (defined as a negative, or microscopically positive second look), and 30 had a poor response (defined as grossly positive second look or progressive disease).
Results: Comparison of tumor markers from the initial and the secondary surgeries revealed that the only significant change was in the Ki67-defined cell proliferation rate, which showed a marked reduction in those with a good response to chemotherapy (P = 0.002). Comparison of tumor markers at initial surgery between good and poor responders revealed a correlation with p53 expression. Good responders were less likely to have p53 overexpression compared to poor responders, and this result approached significance (P = 0.058). Comparison of tumor markers at secondary surgery revealed a significant reduction in Ki67-defined cell proliferation rate in good responders compared to poor responders (P = 0.01). No significant differences were found between good and poor responders for the other tumor markers evaluated.
Conclusions: The only tumor markers to predict for response to chemotherapy were p53 at initial surgery (P = 0.058) and Ki67 indices at secondary surgery (P = 0.001). Expression of steroid hormone receptors, TNFalpha, and P-glycoprotein and overexpression of c-erb-B-2 or EGFR are not associated with chemoresistance.
Copyright 1998 Academic Press.