Prognostic Significance of BMI-1 But Not MEL-18 Expression in Pulmonary Squamous Cell Carcinoma

Aim: We investigated the possibility of BMI-1 and MEL-18 to predict survival in patients with pulmonary squamous cell carcinoma. Materials and Methods: One hundred and ninety-nine patients underwent surgery in our Institute between 1995 and 2005. We used immuno histochemical (IHC) analysis to determine the expressions of BMI-1 and MEL-18 and compared them with clinico-pathological factors and survival. Results: Forty-one of 199 cases (21%) were BMI-1-positive. No correlation was found between BMI-1 and MEL-18 expression by IHC and clinicopathological factors. Five-year overall survival in the BMI-1-positive group (66.8%), but not MEL-18, was significantly better than that in the negative group (45.5%, p=0.04). In multivariate analysis, positive BMI-1 was a better prognostic factor of overall survival (hazard ratio (HR)=0.561, 95% confidence interval (CI)=0.271-1.16, p=0.12). Conclusion: BMI-1 expression, but not MEL-18, is associated with a favorable prognosis and is a possible prognostic factor of pulmonary squamous cell carcinoma.