{"title":"Beyond Standard Endocrine Therapy: A New Adjuvant Treatment in High-Risk Early Breast Cancer","authors":"Barbara Dean, DMSc, PA-C, DFAAPA","doi":"10.6004/jadpro.2024.15.8.11","DOIUrl":null,"url":null,"abstract":"The standard adjuvant treatment of estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative early breast cancer (EBC) is endocrine therapy (ET). Despite this treatment, 20% of patients will have their disease recur. Cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors with ET have shown overall survival (OS) benefit in ER-positive, HER2-negative breast cancer in the metastatic setting. Clinical trials are studying the role of oral CDK4/6 inhibitors in the adjuvant treatment of ER-positive, HER2-negative EBC patients who are clinically and pathologically at high risk for recurrence while on standard ET. The monarchE phase III, randomized, controlled trial, looked at one arm of high-risk ER-positive, HER2-negative EBC patients receiving standard ET and the second arm receiving standard ET with a CDK4/6 inhibitor, abemaciclib. Primary endpoint data showed improvement in invasive disease-free survival of 92.2% in the ET and abemaciclib arm vs. 88.7% in the ET arm at 2 years. At 5 years, a preplanned interim analysis showed continued absolute improvement in invasive disease-free survival. Secondary endpoint data for OS have not yet matured. Abemaciclib is approved for use with ET in patients with high-risk, ER-positive, HER2-negative EBC. This article aims to review a case study and the rationale for using oral CDK4/6 inhibitors as adjuvant treatment for this high-risk subset of patients.","PeriodicalId":17176,"journal":{"name":"Journal of the Advanced Practitioner in Oncology","volume":"69 9","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of the Advanced Practitioner in Oncology","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.6004/jadpro.2024.15.8.11","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
The standard adjuvant treatment of estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative early breast cancer (EBC) is endocrine therapy (ET). Despite this treatment, 20% of patients will have their disease recur. Cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors with ET have shown overall survival (OS) benefit in ER-positive, HER2-negative breast cancer in the metastatic setting. Clinical trials are studying the role of oral CDK4/6 inhibitors in the adjuvant treatment of ER-positive, HER2-negative EBC patients who are clinically and pathologically at high risk for recurrence while on standard ET. The monarchE phase III, randomized, controlled trial, looked at one arm of high-risk ER-positive, HER2-negative EBC patients receiving standard ET and the second arm receiving standard ET with a CDK4/6 inhibitor, abemaciclib. Primary endpoint data showed improvement in invasive disease-free survival of 92.2% in the ET and abemaciclib arm vs. 88.7% in the ET arm at 2 years. At 5 years, a preplanned interim analysis showed continued absolute improvement in invasive disease-free survival. Secondary endpoint data for OS have not yet matured. Abemaciclib is approved for use with ET in patients with high-risk, ER-positive, HER2-negative EBC. This article aims to review a case study and the rationale for using oral CDK4/6 inhibitors as adjuvant treatment for this high-risk subset of patients.