Impact of lapatinib plus trastuzumab versus single-agent lapatinib on quality of life of patients with trastuzumab-refractory HER2+ metastatic breast cancer. - Wu, Y; Amonkar, M M; Sherrill, B H; O'Shaughnessy, J; Ellis, C; Baselga, J; Blackwell, K L; Burstein, H J (Annals of Oncology, 2019)