PRN.

The crux of adjuvant endocrine therapy for breast cancer is long-term medication adherence. Unfortunately several studies show how difficult it can be to optimize what’s universally proven to be pretty poor adherence. This secondary analysis of the prospective CANTO trial was unique in obtaining an objective serum measurement of tamoxifen at just 1 year among 1177 premenopausal women to show that non-adherence (16%) was already clearly associated with worse distant disease-free survival at only 3 years, which was <90% for non-adherent versus 95% for adherent patients. | Pistilli, J Clin Oncol 2020