Zhou X, Cella D, Cameron D, Amonkar MM, Segreti A, Stein S, Walker M, Geyer CE. Lapatinib plus capecitabine versus capecitabine alone for HER2+(ErbB2+) metastatic breast cancer: quality-of-life assessment. Breast Cancer Res Treat. 2009 Oct 1;117(3):577-89. doi: 10.1007/s10549-009-0310-8