Comparison of COX2 expression between oral squamous cell carcinoma, leukoplakia and normal mucosa.

AIM To compare cyclooxygenase 2 expression (COX2-E) between normal, oral leukoplakia lesions and different grades of oral squamous cell carcinoma (SCC). MATERIALS AND METHODS Around 90 paraffin embedded blocks consisting of 45 SCC, 15 leukoplakia and 17 controls were selected for immunohistochemistry (IHC) for detection of COX2- E. COX2-E was divided in four grades, as A (0-10%), B (11- 40%), C (41-70%) and D (< 70%) cellularity. RESULTS Mean age of the patients was 55.17 ± 18.41 (M:57.92 ± 16.87, F:52.19 ± 19.74). A significant difference was found in COX2 expression between SCC total and, basal and spinous layers of leukoplakia (p > 0.05). COX2-E in spinous layer of normal tissue was significantly lower than SCC (p = 0.000). COX2-E was significantly different in SCC grade 3 and leukoplakia (p = 0.001) and normal tissue (p = 0.000). COX2-E was significantly higher in SCC grade 3 compared to leukoplakia (basal layer) (p = 0.000). CONCLUSION We showed a significant higher COX2-E in SCC lesions compared to leukoplakias and normal controls. In our study COX2-E was not significantly different in SCC grades 1, 2 and 3 (p < 0.05).