CA9 and breast cancer: In addition, cut-off values for CDC20, ESM1, UBE2C, and CA9 (11.5101, 14.9784, 13.7558, and 13.4314, respectively) were selected based on the highest combined sensitivity (77.3%, 69.2%, 82.0%, and 64.5%, respectively) and specificity (54.4%, 61.2%, 53.4%, and 68.9%, respectively) for BC.