RESUMO
Background: cyclooxygenase-2 [cox-2] is involved in pathogenesis of various skin tumors including malignant melanoma; however, there is not enough information about cox-2 expression in benign melanocytic lesions. In the present study we compared the expression levels of cox-2 in malignant melanoma and benign melanocytic lesions
Methods: In this analytical study, 42 malignant melanoma from all 4 subtypes and 38 benign melanocytic lesions including dysplastic nevus, Spitz nevus and atypical nevus were evaluated for cox-2 expression using immunohistochemistry staining and intensity of cell staining [quantitatively and qualitatively]
Results: Malignant melanoma compared to benign melanocytic lesions had significantly higher levels of staining [p<0.00l], and much more intense coloration [p<0.00l] and higher overall staining score [p<0.001]
Regarding the cox-2 staining between malignant melanoma subtypes, all four subtypes mostly had staining intensity over 60%. Also in terms of quality, the most intense staining was in the ALM, and LM and NM had moderate staining intensity. With increasing depth of involvement, cox-2 staining increases. Intensity of cell staining was also higher in cases with tumor depth of 2-4 mm
Conclusion: The results indicate the effectiveness of cox-2 in differentiating between malignant melanoma and benign melanocytic lesions, cox-2 expression correlated with the depth of invasion. Although cox-2 alone cannot be used to differentiate melanoma from benign lesions, it can be helpful in combination with other methods, in determining the prognosis and future targeted therapies