COMP and breast angiosarcoma: As shown in Fig. 2C, the analysis displayed that the optimal cutoff value of circulating COMP as a useful biomarker for discriminating BA patients from healthy control was projected to be 97.80 ng/mL, which provided a sensitivity of 100.0%, a specificity of 98.2%, and an AUC of 0.99 (95% CI 0.97 to 1.00, P < 0.001).