Comparing the immunohistochemistry expression of COX-2 in pigmented benign and malignant skin neoplasms

Background: Skin cancer is one of the most common types of cancer that arises from skin that annual mortality rate are increasing. The induction enzyme of cyclooxygenase COX-2causes biosynthesis of prostaglandin and thromboxane during inflammation of the body. Increasing the expression of COX-2 has an important role in the development andprogression of malignant epithelial cancers and other types of cancers. Considering the diagnostic status of this marker, this study aimed to evaluate the expression of COX-2 as amarker for the diagnosis and differentiation of benign skin pigmented neoplastic lesions from malignant melanoma types Method: This is a diagnostic study to investigate the incidence of immunohistochemistry expression of COX-2 in 82 paraffin blocks (49 men, 33 women) of pigmented benign and malignant skin neoplasms in patients referring Buali Sina hospital of Sari during March 2015-2016 and its association with clinic pathologic features of the tumor was evaluated. Results: The findings showed that 20 patients (24.3%) had malignant melanoma and 13 patients had significant COX-2 (3+ High), while significant COX-2 marker were not detected in other benign and malignant pigmented skin neoplasms (p<0.001). A significant association were found between COX-2 marker and grade (p<0.001) but there was no significant correlation with other clinic pathologic tumor criteria. Sensitivity, specificity PPV and NPV value of the COX-2 marker were 65%, 100%, 89.9% and 100%, respectively. Conclusion: Due to the high level of COX-2 in malignant melanoma skin marker, it can be used in addition to distinguishing between benign and malignant neoplastic lesions (SCC and BCC) from melanoma, to provide effective therapeutic strategies through specific COX-2 enzyme inhibitors.

Keywords:

Cyclooxygenase-2 , Neoplastic lesions , Skin cancer , Melanoma , Immunohistochemistry