Manganese superoxide dismutase and glutathione peroxidase as prognostic markers in patients with buccal mucosal squamous cell carcinomas

Background We investigated the relationship of the immunohistochemical expression status of manganese superoxide dismutase (MnSOD), catalase, glutathione peroxidase (GPx), and myeloperoxidase (MPO) in buccal mucosal squamous cell carcinoma (SCC) with clinicopathologic parameters and prognosis. Methods The expression status of MnSOD, GPx, catalase, and MPO was evaluated by immunohistochemistry in a series of 216 surgically resected buccal mucosal SCC specimens, using tissue microarray slides. Results MnSOD, GPx, catalase, and MPO were commonly expressed in buccal mucosal SCC. The high expression level of MnSOD was associated with better disease-specific survival (p =.009), especially for patients in moderate or poor cell differentiation (p =.045), pathologic stage I (p =.002) and postoperative radiotherapy (p =.048). The high expression level of GPx was also correlated with better disease-specific survival (p =.042), especially for patients in pathologic stage IV (p =.010) and postoperative radiotherapy (p =.018). Conclusions MnSOD and GPx are significant prognostic factors for favorable survival in patients with buccal mucosal SCC.