ERBB2 and metastatic neoplasm: However, the authors found that in the hormone receptor (HR)-negative subpopulation, everolimus-treated patients achieved a median PFS of 20.27 months versus 13.08 months with placebo (HR = 0.66, P.0049).[37] Taken together, BOLERO-1 and 3 appear to demonstrate that the benefit of adding mTOR inhibitor to chemotherapy and trastuzumab in the metastatic disease setting is great in the HER2+ hormone receptor negative cohort.