Recent reports have shown that CXCR4 is expressed in various solid
tumors and is involved in
tumor development and
metastasis. We examined the distribution and expression of this molecule in clear cell
carcinoma of the ovary to elucidate its clinical significance.
Paraffin sections from clear cell
carcinoma of the ovary tissues (n = 42) were immunostained with CXCR4 antibody, and the staining intensities were evaluated. The clinicopathologic factors examined were age, FIGO (International Federation of Gynecology and Obstetrics) staging, preoperative value of
cancer antigen 125 test, and
residual tumor after
cytoreductive surgery. Overall survival and progression-free survival were evaluated using the Kaplan-Meier method, and multivariate analysis was completed using Cox proportional hazards analysis. Of the 42
carcinomas, lower level CXCR4 immunoexpression was observed in 21 cases (50.0%) (CXCR4(low) group); and higher level immunoexpression, in 21 cases (50.0%) (CXCR4(high) group). Five-year overall survival was significantly poorer in the CXCR4(high) group than in the CXCR4(low) group (overall survival, CXCR4(low) group [90.2%], CXCR4(high) group [50.3%]; P = .0002). In addition, CXCR4(high) immunoexpression significantly predicted a poorer progression-free survival when compared with lower expression (5-year progression-free survival, CXCR4(low) group [90.5%], CXCR4(high) group [36.2%]; P < .0001). Furthermore, multivariate analyses including the age, preoperative
cancer antigen 125 test value, FIGO stage, and CXCR4 expressions revealed that CXCR4(high) expression was an independent prognostic factor for poorer overall survival and progression-free survival of patients with clear cell
carcinoma of the ovary (overall survival, P = .0011; progression-free survival, P = .0008, respectively). Our current study suggested that the assessment of CXCR4 immunoreactivity may be a useful prognostic
indicator and that CXCR4 may play a critical role in the progression of clear cell
carcinoma of the ovary.