Review of the monarchE trial suggests no evidence to support use of adjuvant abemaciclib in women with breast cancer.

Abstract

When localised cancer is resected surgically, some patients will have recurrence of their disease, and the likelihood of dying from the cancer is then high. Adjuvant therapies are offered before or after surgery in the hope of reducing the probability of recurrence, thereby improving survival. The scientific and clinical community is continuously searching for new adjuvant therapies that can increase survival and cure rates, but when potential advances are proposed, the data must be carefully analysed to establish if the new therapy performs as we hope. Only some patients recur, such that—by default—adjuvant therapy overtreats many patients in the hope of curing a few more. Review of the monarchE trial suggests no evidence to support use of adjuvant abemaciclib in women with breast cancer – Authors' replyThe monarchE investigators respectfully disagree with the comments of Tomer Meirson and colleagues in their Essay in The Lancet Oncology regarding the role of adjuvant abemaciclib in patients with early breast cancer. monarchE was a large, global, randomised study conducted in patients with high-risk, hormone receptor-positive, HER2-negative, early breast cancer.1 This population was selected on the basis of their substantial unmet medical need, as shown by the high risk of recurrence observed in the control group (>20% at 4 years); outcomes that justified consideration of additional treatment with abemaciclib. Full-Text PDF