BDNF and breast cancer: Compared to patients who remained disease free, higher BDNF expression was significantly associated with local recurrence (LR) (absolute mean copy number 6660 vs. 7430, p = 0.0014), death from BC (absolute mean copy number 6660 vs. 49945, p = 0.018) and approached significance for those developing metastases (absolute mean copy number 6660 vs. 33787, p = 0.078) (Figure 6).