ERBB2 and breast cancer: Productivity data from the MONALEESA-7 trial, obtained from the results of the application of the Work Productivity and Activity Impairment (WPAI) questionnaire on progression-free survival state (43-month follow-up), were extrapolated to the 10,936 Brazilian prevalent cases of premenopausal women with hormone receptor positive/human epidermal growth factor receptor 2 negative (HR+/HER2-) breast cancer.