DOI: 10.6084/m9.figshare.27231093.v1
title: Disease landscape of advanced HER2-breast cancer patients by treatment line in three EU countries and USA

description: <b>Aim:</b> To report treatment patterns and quality of life (QoL) in HER2-negative advanced breast cancer patients. <b>Methods:</b> Data were drawn from a cross-sectional survey in Europe and USA. <b>Results:</b> Hormone plus targeted therapy was the most frequent first-line (1L, 62%) and second-line (2L, 45%) treatment for HR+/HER2-patients. Chemotherapy was most frequent at third-line or greater (3L+, 39%) for HR+/HER2- patients, 2L (51%) and 3L+ (48%) for triple negative breast cancer (TNBC) patients. Time to progression was 13.8 (2L) and 11.0 (3L+) months for HR+/HER2- patients. No comparisons were observed for TNBC patients. EQ-5D-5L scores were highest in patients at 1L and lowest at 3L+. <b>Conclusion:</b> Reduced QoL and treatment response were reported in patients at later lines of therapy. Breast cancer is the most common cancer in women. Differences in survival are seen depending on how widespread or advanced the cancer is, how many different treatments the patient has been given, as well as whether certain receptors on the tumor are present or absent. Many new treatments are available which can target these receptors. These treatments have improved survival in patients with advanced breast cancer, but other benefits for the patient are not always clear. In addition, differences between countries are possible as official guidance can vary. This study aimed to understand these issues, by asking physicians and their patients across Europe and USA for their views on quality of life and satisfaction with their treatments. We found that, in general, physicians prescribed treatments as recommended in the treatment guidelines. As breast cancer progressed and treatment stopped working, patients were switched on to different treatments. Survival, quality of life and treatment satisfaction were all worse in patients who had switched treatments. It appears that the patients lose confidence that their new treatment will work to improve their quality of life. We also saw differences in some of these outcomes between Europe and USA, which were likely due to differences in the treatment guidelines between countries. Both quality of life and treatment satisfaction are important for the well-being of patients with advanced breast cancer as they now live longer with these new treatments. This should be considered by physicians and taken into account for future work. Given the rapidly evolving treatment landscape for patients with advanced breast cancer (ABC), the aim of this analysis was to describe treatment patterns, quality of life (QoL) outcomes, and treatment satisfaction at subsequent treatment lines (first- [1L], second- [2L]; third/later- [3L+] lines) among patients with hormone-receptor positive (HR+)/human epidermal growth factor-negative (HER2-) and triple negative breast cancer (TNBC) in Europe (France, Italy and Spain) and USA in a real-world setting. Data were drawn from the Advanced Breast Cancer (ABC) Disease Specific Programme<sup>™</sup>, a point-in-time survey of physicians and their consulting patients conducted in Europe and the USA 2019–2020. Median time to progression at 2L and 3L was 13.8 and 11.0 months for patients with HR+/HER2, and 8.0 and 4.6 months, respectively for TNBC patients; patient overall response rates at 1L, 2L and 3L+ were 54, 53 and 42%, respectively. The average EuroQol-5 dimensions-5 level (EQ-5D-5L) health utility score of HR+/HER2- and TNBC patients was 0.77 at 1L, 0.70 and 0.71 at 2L, and 0.65 and 0.79 at 3L+, respectively; EQ-5D-5L visual analog scale mean score was 70.9, 67.4, and 63.4 for HR+/HER2- patients, and 69.4, 65.2, and 65.8 for TNBC patients, at 1L, 2L and 3L+, respectively. The Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30) global health status mean score was 64.6, 60.0 and 57.7 for HR+/HER2- patients, and 64.0, 61.2 and 59.3 for TNBC patients, at 1L, 2L and 3L+, respectively; there was a small meaningful difference between scores at 1L and at 2L and 3L+. EORTC scores were generally higher at 1L and lower at 3L+ in HR+/HER2- patients' functioning and symptoms. This differed for TNBC patients where scores were higher in 3L+ patients compared with 2L patients for physical, role, emotional, cognitive and social functioning. Meaningful differences in the scores at 2L and/or 3L+ were seen for most functioning scales, particularly in cognitive functioning and social functioning, and over half of the symptom scales in HR+/HER2- patients. Physicians were ‘satisfied’ or ‘very satisfied’ with current treatment for 77%, HR+/HER2- and 68% TNBC patients on 1L, 73% HR+/HER2- and 57% TNBC patients on 2L, and 59% HR+/HER2- and 54% TNBC patients on 3L+; likewise, patients' treatment satisfaction was reduced for both patient populations. This analysis demonstrated that patients with HR+/HER2- and triple negative ABC treated with 3L+ therapy, compared with patients treated with 1L or 2L therapies, reported a reduction in QoL, while concurrently, time to progression was shorter and overall response rate was poorer; similarly, satisfaction with treatment was reduced for both physicians and patients.