PROGNOSTIC UTILITY OF EPIDERMAL GROWTH-FACTOR RECEPTOR OVEREXPRESSIONIN ENDOMETRIAL ADENOCARCINOMA

Background. Overexpression of epidermal growth factor receptor (EGFR) has been reported in endometrial adenocarcinoma. Methods. A retrospect ive analytic study was designed to investigate its prognostic utility. Sixty-nine patients were studied with cell types that included endome trioid (n = 45), papillary serous (n = 16), and clear cell (n = 8). Pa tients' medical charts and survival data were reviewed. Assessment of EGFR overexpression was done at the protein level by the use of an ant i-EGFR polyclonal antibody that reacts with the cytoplasmic membrane g lycoprotein receptor in paraffin-embedded tissues. Results. EGFR was o verexpressed in 34 (49%) patients in whom immunoreactivity was limited to neoplastic cells. Initial bivariate analysis revealed significant correlations between EGFR immunoreactivity and histologic grade (r = 0 .44, P < 0.001), metastasis (r = 0.38, P < 0.001), cell type (r = 0.30 , P < 0.01), myometrial invasion (r = 0.30, P < 0.01), and patient age (r = 0.30, P < 0.01). Multiple logistic regression analyses showed th at EGFR overexpression and nonendometrioid cell types are two independ ent statistically significant markers for the presence of metastases. EGFR immunoreactivity can significantly predict myometrial invasion, b ut after controlling for the histologic grade, its ability of signific antly predict invasion was lost. EGFR overexpression was shown to be a statistically significant predictor of survival, even after controlli ng for patient age, histologic grade, and cell type. Conclusions. Expr ession of this oncoprotein may serve as an independent prognostic indi cator and a guide to therapy in patients with endometrial cancer.