CALCA and breast cancer: This finding, together with the fact that at 0.37 ng/ml or lower PCT cut-off values, the number of missed pathogens by BC was significantly higher than that of pathogens missed by SF, highlights the notion that BC remains a mainstay for the identification of microorganisms in bloodstream infections and that SF must be considered as an additional tool in selected patients, whenever a quick etiological diagnosis is required for an appropriate and timely clinical management.