ERBB2 and metastatic neoplasm: In terms of TTBM from initial diagnosis of metastatic disease, median TTBM was significantly shorter in TNBC patients (2.9 months) and HER2-positive without trastruzumab treatment (5.8 months) compared patients with HR-positive/HER2-negative (17.5 months) or HER2-positive patients who received trastuzumab (13.7 months).