Prognostic value of CD133 expression in stage I lung adenocarcinomas.

CD133 is one of the most representative cancer stem cell markers. This study evaluated the potential prognostic value of CD133 expression in stage I lung adenocarcinomas (ADC). Tumors from 177 patients were immunohistochemically examined for CD133 expression, and their associations with disease recurrence were analyzed. Also, the potential prognostic value of combining CD133 expression with proliferating activity measured by immunohistochemical expression of Ki-67 and vessel involvement was evaluated. CD133 high expressers showed a significantly higher risk of recurrence than CD133 low expressers: 5-year disease-free survival (DFS) rate 77.2% vs. 95.1% (p=0.004), adjusted Hazard ratio (HR) 4.37, 95% Confidence Interval (CI) 1.30-14.71 (p=0.017). CD133 high expressers having strong proliferating activity and/or with vessel invasion showed a higher risk of recurrence: 5-year DFS rate 66.5% in CD133 high/Ki-67 high expressers vs. 93.2% in the other types (p<0.001), adjusted HR 8.39, 95% CI 2.65-26.54 (p<0.001): 5-year DFS rate 51.0% in CD133 high expressers with vessel invasion vs. 92.9% in the other types (p<0.001), adjusted HR 4.50, 95% CI 1.51-13.34 (p=0.007): 5-year DFS rate 53.9% in CD133 high/Ki-67 high expressers with vessel invasion vs. 91.2% in the other types (p<0.001), adjusted HR 9.32, 95% CI 3.42-25.39 (p<0.001). In conclusion, the level of CD133 expression is an independent prognostic marker and its combination with proliferating activity and/or vessel invasion could have excellent prognostic value to predict postoperative recurrence in patients with stage I lung ADC.