Comparison of Cox_2 expression in radiation induced BCC and non radiation induced BCC

Introduction: Radiation induced basal Cell Carcinoma(BCC) can be multiple, large and with recurrence that can Make it difficult to treat. Regarding the reports about the role of Cox-2 inhibitors in treatment or prevention of non melanoma skin cancers, and since Cox_2 expression in radiation induced BCC has not been investigated before, we decided to evaluate Cox_2 expression in these lesions.Methods: In this study, the incidence of cox-2 was evaluated with Immunohistochemistry using antibodies against cox-2 in paraffin embedded blocks of 86 patients referred to Imam Reza Hospital in Mashhad with pathologic diagnosis of BCC ( 43 patients with and 43 patient without history of radiotherapy) and semi-quantitative assessment of cox-2 was performed . the samples were divided according to percent of staining of the cells (p) to five distinct groups ( less than 1 % , 1-25 % , 26-50 %, 51-75 % , 76-100 % ) and staining intensity (I) to four groups (negative , weak, moderate , severe ), then in each case sum of the staining percent and staining intensity was named score of cox-2 expression. Accordingly , samples based on cox-2 score were divided to 3 groups : Group 1 with a score 0-2 ( negative ), Group 2 with a score 3-4 and Group 3 with a score 5-7 (strongly positive Results:Intensity and percentage of staining of tumor cells and the score of Cox-2 expression was significantly higher in patients with radiotherapy than patients without a history of radiotherapy. ( Pvalue<0.001). We found no association between staining intensity and percentage and score with gender, age , tumor location, pathologic type and tumor recurrence.Conclusion: According to higher expression of Cox-2 in patients with radiation induced BCC , the use of Cox-2 inhibitors may be effective in the prevention of recurrence or treatment of BCC.

Keywords:

Basal cell carcinoma , Cox-2 , Immunohistochemistry , Radiotherapy