Abstract B097: Empowering Latina breast cancer patients: A phone app + patient navigation to improve hormone therapy adherence

Abstract Background: Hormone therapy (HT) is highly effective for nearly all breast cancer patients with hormone receptor-positive tumors, which comprise about 80% of all breast cancer diagnoses. Cancer recurrence rates and mortality risks are reduced by nearly half with long-term HT use. Despite these benefits, 33% of women prescribed HT do not adhere to their medication (<80% take their daily dosage). Latina patients are disproportionately affected by Non-Medical Drivers of Health (NMDoH), which hinder adherence, placing them at greater risk for breast cancer recurrence and mortality. Study Goal: This parallel 3-group randomized controlled trial will assess the effectiveness of the HT Helper app + Patient Navigation (PN) vs. PN alone vs. usual care on HT adherence. It will also assess the effect of each study condition on patient self-efficacy to identify side effects, use self-care to manage side effects, and communicate with their medical team. This study builds on a prior pilot study exploring the feasibility and acceptability of the HT Helper app. We will present results from formative research activities, including beta-testing, focus groups, and the final refinement of the existing bilingual, culturally tailored HT Helper app. Methods: Twelve Latina breast cancer patients from the Breast Clinic at the Mays Cancer Center, receiving HT and experiencing NMDoH-related barriers, participated in formative research activities. Beta-testing involved a comprehensive week-long use of the HT Helper app, followed by participation in a focus group based on the participants' language preferences (English or Spanish). Focus group participants provided feedback on all app features, including the home page, educational content and videos, symptom tracking tools, motivational messages, general design, and the User Guide. After integrating participant recommendations, the refined app was tested again by participants for one more week. Results: The majority of beta-testers expressed positive feedback regarding the HT Helper app, finding it informative, highly useful, and user-friendly. Key suggestions included: expanding on the details of specific symptoms and side effects of cancer treatment and HT; proposing topics for the "Chat with a Doctor" feature; including updated patient testimonials; and modifying the color scheme and design of the app homepage to enhance visual appeal. Conclusion: An iterative, patient-centered development process was employed to ensure that the voices of the patients were integral to the refinement of the app, making it more engaging and user-friendly for the current study. This innovative, multi-level intervention is designed to promote equitable breast cancer outcomes, including reducing recurrence, enhancing quality of life, and improving overall survival and life expectancy among underserved Latina patients. The anticipated outcome is a scalable, evidence-based intervention that is easy to disseminate and has broad applicability for patients using oral anticancer medications. Citation Format: Patricia Chalela, Vivian Cortez, Sandra Sivak, Armida Flores, Zully Garcia, Mauren Duran, Shayannie Sierra, Maria Sung-Cuadrado, Ashley Trejo, Byeong Choi, Edgar Muñoz, Cliff Despres, Alyssa Gonzales, Virginia Kaklamani, Kate Lathrop, Marcela Mazo Canola, Devasena Inupakutika, David Akopian, Amelie G. Ramirez. Empowering Latina breast cancer patients: A phone app + patient navigation to improve hormone therapy adherence [abstract]. In: Proceedings of the 18th AACR Conference on the Science of Cancer Health Disparities; 2025 Sep 18-21; Baltimore, MD. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2025;34(9 Suppl):Abstract nr B097.