Bone-targeted agent treatment patterns and the impact of bone metastases on patients with advanced breast cancer in real-world practice in six European countries

BACKGROUND: Bone metastases (BMs) are common in patients with breast cancer and can lead to skeletal-related events (SREs), which are associated with increased pain and reduced quality of life (QoL). Bone-targeted agents (BTAs), like zoledronic acid and denosumab, reduce the incidence of SREs and delay progression of bone pain. MATERIALS AND METHODS: We evaluated the management of BMs and pain in six European countries (Belgium, France, Germany, Italy, Spain, and UK) using the Adelphi Breast Cancer Disease Specific Programme, which included a physician survey and patient-reported outcomes (PROs) to assess the impact of BMs on pain and QoL. RESULTS: 301 physicians completed patient record forms for 2984 patients with advanced breast cancer; 1408 with BMs and 1136 with metastases at sites other than bone (non-BMs). Most patients with BMs (88%) received a BTA, with 81% receiving treatment during 3 months following BM diagnosis. For those who did not receive a BTA, the main reasons given were: very recent BM diagnosis, perceived low risk of bone complications, and short life expectancy. Most patients with BMs (68%) were experiencing bone pain and, of these, 97% were taking analgesics (including 28% receiving strong opioids). Despite this, moderate to severe pain was reported in 20% of patients who were experiencing pain. PROs were assessed in 766 patients with advanced breast cancer (392 with BMs, 374 with non-BMs). Overall, patients with BMs reported worse pain and QoL outcomes than those with non-BMs, those not receiving a BTA reported worse pain. CONCLUSION: Despite the large proportion of patients receiving BTAs in this study, some patients with BMs are still not receiving early treatment to prevent SREs or to manage pain. Improving physicians’ understanding of the role of BTAs and the importance of early treatment following BM diagnosis has the potential to improve patient care.