High expression of epidermal growth factor-like domain 7 is correlated with poor differentiation and poor prognosis in patients with epithelial ovarian cancer

OBJECTIVE: The purpose of this study was to evaluate the expression of epidermal growth factor-like domain 7 (EGFL7) in epithelial ovarian cancer, and to assess its relevance to clinicopathological characteristics and patients' survival. METHODS: A total of 177 patients with epithelial ovarian cancer were enrolled in the current study. For each patient, a retrospective review of medical records was conducted. Immunohistochemical staining for EGFL7 was performed using tissue microarrays made with paraffin-embedded tissue block. EGFL7 expression levels were graded on a grade of 0 to 3 based on the percentage of positive cancer cells. We analyzed the correlations between the expression of EGFL7 and various clinical parameters, and also analyzed the survival outcome according to the EGFL7 expression. RESULTS: The expression of EGFL7 in ovarian cancer tissues was observed in 98 patients (55.4%). High expression of EGFL7 (grade 2 or 3) was significantly correlated with pathologic type, differentiation, stage, residual tumor after debulking surgery, lymphovascular space involvement, lymph node metastasis, high cancer antigen 125, peritoneal cytology, and ascites. Among these clinicopathologic factors, differentiation was significantly correlated with EGFL7 expression in multivariate analysis (p<0.05). Survival analysis showed that the patients with high EGFL7 expression had a poorer disease free survival than those with low EGFL7 expression (p=0.002). CONCLUSION: Our data suggest that EGFL7 expression is a novel predictive factor for the clinical progression of epithelial ovarian cancer, and may constitute a therapeutic target for antiangiogenesis therapy in patients with epithelial ovarian cancer.