Increased Cyclooxygenase-2 Expression Associated with Inflammatory Cellular Infiltration in Elderly Patients with Vulvar Cancer

Abstract

As the relationship between inflammation and carcinogenesis grows stronger, the role of cyclooxygenase-2 (COX-2) and epidermal growth factor (EGFR) has been highlighted in the pathogenesis and progression of human cancer. In view of the fact that vulvar cancer is characterized by precancerous inflammatory changes in elderly patients, the expressions of COX-2 and EGFR are expected to show different patterns of distribution according to age and other prognostic factors. To verify whether there was a relationship between their expression and clinicopathologic parameters in vulvar cancer, we investigated the inflammatory cellular infiltration and the expression of COX-2 and EGFR by immunohistochemical analysis. Eleven of 19 samples (57.8%) were stained positive for COX-2, and 17 (89.4%) for EGFR. The portion of inflammatory cellular infiltration in adjacent normal tissue was also higher in the older age group, and showed a strong correlation with COX-2 positivity (P = 0.002). Furthermore, COX-2 expression was significantly more frequent in patients over 60 years of age compared to those under 50 years (P = 0.009). COX-2 expression was noted to be high in moderate and well-differentiated cases, whereas, poorly differentiated carcinoma was negative for COX-2 expression (P = 0.023). However, EGFR expression was not differently distributed on the basis of stage, age, tumor grading, or presence of lymph node metastasis. Our article suggests that vulvar cancer in elderly patients may be associated with inflammation, and thus with increased COX-2 expression. In light of these findings, a clinical trial designed to assess the addition of COX-2 targeted therapy to conventional treatment in vulvar cancer would be helpful for consideration of additional treatment options and possibly avoiding the serious surgical morbidity in elderly patients.