Patient Experience with MBC Treatment

Introduction

Endocrine therapy (ET) is commonly used in the treatment of breast cancer, including both oral and intramuscular (IM) options. While ET is an effective treatment for breast cancer, the two administration modes may generate disparate burdens and benefits on patients’ everyday lives.

This study aims to explore metastatic breast cancer (MBC) patients’ experiences with ET by describing the burdens (including challenges to administration and adherence), benefits, and preference of oral and IM ET.

This study was sponsored by Eli Lilly and Company. 

Authors

Erica E. Fortune, PhD¹, Abigail Newell,PhD¹, Maria Gonzalo, MS¹, Rebecca M. Speck², Adrienne M. Gilligan², Alexandra S. Vitko²

1. Cancer Support Community, Washington, DC, USA
2. Eli Lilly and Co
    

Methods

Adults in the U.S. with metastatic breast cancer who had taken both oral and IM endocrine therapy for at least three months completed an online survey, recruited through Cancer Support Community sites and advocacy groups. The survey captured sociodemographic and clinical data, along with patient-reported benefits and burdens of each treatment modality and overall treatment preferences. Participants also rated the importance of various factors in treatment decision-making; findings are based on ongoing, interim data collection.

 

Results

Interim data from 100 women with metastatic breast cancer (mean age 54; average 6.6 years since diagnosis) show a clear preference for oral endocrine therapy (ET) over intramuscular (IM) ET, primarily due to convenience, reduced pain, and lower impact on daily life. While oral ET was viewed as easier to access and less burdensome, it was associated with slightly lower adherence compared to IM ET. In contrast, IM ET was easier to remember but frequently associated with pain and discomfort. Across treatment decisions, patients prioritized slowing disease progression, followed by the potential to cure the disease and minimizing impact on daily life.

Conclusions

Findings indicate a clear preference for oral over IM endocrine therapy, driven by greater convenience, ease of access, and less disruption to daily life, though daily dosing can introduce some stress or anxiety. While self-reported adherence was higher for IM therapy, missed doses carry different implications given its monthly schedule versus daily oral dosing. Overall, the results highlight the importance of shared decision-making to align treatment choices with patient preferences.

Keywords

 Metastatic Breast Cancer  Symptoms and side effects Emotional and mental health Quality of life