ERBB2 and breast cancer: Among breast cancer subtypes, the OS for refractory (3-year, 65%; 5-year, 56%) and sensitive (3-year, 83%; 5-year, 76%) disease was significantly lower in the TNBC subtype compared with other subtypes (HR+ refractory: 3-year, 88%; 5-year, 79%; sensitive: 3-year, 90%; 5-year, 83%; ERBB2+ refractory: 3-year, 85%; 5-year, 77%; sensitive: 3-year, 92%; 5-year, 86%; P < .001) (eTable 2 in Supplement 1).