Figure 2: Expression of HSP90α, CEA, and CA153 in nipple discharge and the diagnostic value of HSP90α and CEA. (a-c) Compared with nipple discharge of patients with benign disease, HSP90α and CEA were upregulated in nipple discharge of patients with breast cancer. There was no significant difference in the expression of CA153 in benign and malignant nipple discharge (128 samples were available for HSP90α detection, 123 samples for CEA detection, and 124 samples for CA153 detection). (d) Receiver operating characteristic (ROC) curve analysis of HSP90α in the diagnosis of breast cancer. The AUC was 0.8268 (P < 0.0001). Based on the Youden Index, a diagnostic cutoff value of 281.7 ng/ml was found. The sensitivity and specificity of HSP90α in the diagnosis of breast cancer were 84.38% and 84.38%, respectively. (e) ROC curve analysis was performed to evaluate the diagnostic value of CEA in breast cancer. The AUC was 0.7086 (P = 0.0005). Based on the Youden Index, a diagnostic cutoff value of 494.5 ng/ml was found. CEA had a sensitivity of 51.61% and specificity of 90.22% for the diagnosis of breast cancer. (f) ROC curve analysis of the combination of HSP90α and CEA for the diagnosis of breast cancer. The AUC was 0.857 (P < 0.0001). AUC: Area under the curve, CEA: Carcinoembryonic antigen, CA153: Cancer antigen 153, HSP90α: Heat shock protein 90α.