Abstract
Endocrine therapy (ET) is a standard part of the treatment of hormone-sensitive (HR+) breast cancer. Despite the escalation of this treatment in the form of extended adjuvant ET and/or combined ET with the addition of LHRH analogues in premenopausal women, a significant proportion of patients with early breast cancer are burdened with relapses of the disease.
This is particularly the case for high-risk patients with lymph node involvement, in whom relapses are often late, after completion of the 5-year ET. It is therefore clear that even prolonged adjuvant ET is not sufficient to prevent disease recurrence.
In addition, there is a subset of patients with primary hormone resistance that does not respond to standard ET and relapses early after surgery. Both groups of patients are candidates for escalation treatment based on a combination of standard ET and a cyclin-dependent kinase inhibitor (CDK).
This strategy proved to be very effective in monarchE study, in which risk patients were treated with a combination of ET with abemaciclib. The adjuvant CDK inhibitor (abemaciclib) indication has already been approved as a new treatment standard for high-risk patients.