Darlix A, et al. - Between 2007 and 2015, researchers retrospectively analyzed 244 candidates for a median follow-up of 40.8 months to evaluate the prognostic value of Tau (and other classical biomarkers) in metastatic breast cancer (MBC) cases, and also to estimate its relationship with the presence of brain metastases (BM). They observed a median OS of 15.5 months. They found an association of elevated serum levels of Tau with a poor consequence in the whole population and also in outpatients with/without BM. They also noticed an increased risk of serum Tau > 3.17 pg/mL among candidates with BM in univariate analysis.