Evaluation of Cyclooxygenase-2 Expression in Association with Clinical-Pathological Factors in Malignant Melanoma

BACKGROUND AND OBJECTIVE: The primary goal of this study is to develop a rigorous understanding of the correlation between COX-2 expression and malignant melanoma prognostic factors. MATERIAL AND METHODS: In this cross-sectional study, we analyzed 60 cases of cutaneous malignant melanoma. The related stained slides were reviewed by two pathologists. The results were interpreted according to the COX2 staining index (SI), tumor thickness (Breslow, Clark), number of mitoses per 10 hpf, and melanoma types. Gender, lymph node involvement, metastasis, and survival were considered as evaluation factors as well. RESULTS: The expression of the COX-2 protein was evident in 98.4% of cases. A strong Staining Index(SI) was reported in 60% of all melanomas, moderate staining was detected in 20.8% and weak staining in 10%; 1.6% of studied cases showed no staining. Benign nevus specimens showed no staining for the COX-2 enzyme. CONCLUSION: We have demonstrated that COX-2 is strongly expressed in the majority of malignant melanomas and that the SI score of COX-2 is related to the number of mitoses, tumor thickness (based on Clark level and Breslow), melanoma sub-type, lymph node involvement, and metastases; No association was noted between the anatomic site, gender, and survival. COX-2 can be applied as a prognostic factor in malignant melanoma and a promising candidate for future target therapies.