New Results Shaping Recommendations in Early-Stage HR+ Breast Cancer

William J. Gradishar, MD, discusses the impact of new data on the National Comprehensive Cancer Network guidelines for patients with early-stage breast cancer.

William J. Gradishar, MD, chief of Hematology and Oncology in the Department of Medicine, Betsy Bramsen professor of Breast Oncology, and professor of Medicine (Hematology and Oncology) at Northwestern Medicine, Feinberg School of Medicine, discusses the impact of new data on the National Comprehensive Cancer Network (NCCN) guidelines for patients with early-stage breast cancer. In particular, he focuses on the monarchE clinical trial (NCT03155997) and how that has impacted the landscape for patients with hormone receptor (HR) positive breast cancer.

The open label phase 3 study looked at HR positive, HER2 negative, high-risk patients early-stage breast cancer who had surgery on abemaciclib (Verzenio) plus endocrine therapy vs standard of care endocrine therapy without abemaciclib. Results from the study showed that the combination therapy yielded better invasive disease-free survival (IDFS) with a 2-year IDFS rate of 92.2% in the treatment arm vs 88.7% for patients on endocrine therapy alone (HR 0.75; 95% CI, 0.60-0.93; P = .01).

The results of the trial led to the approval of abemaciclib, in combination with endocrine therapy, for the adjuvant treatment of adult patients in this setting who were at a high risk of recurrence with a Ki-67 score of 20% or greater. However, in an interview with Targeted OncologyTM, while the study showed the merits of this treatment for this subgroup he cautioned that not all patients need to receive such a long treatment as patients would stay on treatment for a minimum of 2 years.


0:07 | So, what we're doing in [updating the] breast cancer guidelines is reflecting new data that becomes available, and I guess the things that have changed most recently are in the HR positive breast cancer space. Patients that are at significant risk for recurrence have a couple of potential options. One based on the monarchE trial is the inclusion of CDK4/6 inhibitors, specifically abemaciclib for patients who either have 4 more lymph nodes or 1-3 lymph nodes, and some other features that put them in high risk. [Such as having] either a bigger tumor or a high k67.

0:46 | And in that subset of patients, since the risk is high, abemaciclib in the monarchE trial was shown to further reduce the risk of recurrence. So, it's a consideration for those patients. We wouldn't use it in node negative patients or patients that have a generally good prognosis, because you're really committing patients, based on the trial, to 2 years of a CDK4/6 inhibitor, which on its own has some potential [adverse events]. So, it's for the highest risk patients.