Patterns of care for patients with metastatic bone disease in solid tumors: A cross-sectional study from Switzerland (SAKK 95/16)

Highlights • Implementation of guideline-recommended BTA practice is high among Swiss physicians. • Denosumab is the BTA of choice in Switzerland. • BTAs were widely administered (94.2%) according to a 3–4-weekly dosing regimen. • Bone pain and SRE incidence were low in patients with solid tumor bone metastases. • Low SRE incidence may indicate BTA efficacy and judicious BTA prescribing.
Background Bone-targeted agents (BTAs) are widely used in the management of patients with bone metastases from solid tumors, but knowledge of their routine care use and the therapeutic implications remains limited. This non-interventional study aimed to characterize real-world BTA patterns of care in Switzerland. Materials and methods Non-interventional, cross-sectional study involving oncologists from across Switzerland who completed a Treating Physician questionnaire, providing data on their clinical setting and BTA-related practices, and a Patient Characteristics and Treatment questionnaire, providing data on their patients’ disease status, risk of bone complications, BTA regimen and related outcomes. Eligible patients were aged ≥ 18 years, with solid tumors and at least one bone metastasis and were receiving routine management at the participating physician's center over the 3-month study period. Results A total of 86 oncologists recruited 417 patients from across 18 centers in Switzerland (80% public hospitals; 20% private clinics). The majority of physicians (70.9%) reported prescribing BTAs in line with international guidelines; denosumab was the treatment of choice in 78.5% of patients. BTAs were widely administered (94.2%) according to a 3–4-weekly dosing regimen; 33.7% of physicians reported extending intervals to 12 weeks after an initial 2 years of treatment. Physicians appeared to use clinical judgement, as well as formal risk assessment, to guide treatment for symptomatic skeletal events. No association was seen between either BTA use, or risk of complications, and incidence of skeletal complications. Only 4.3% of patients were reported to be experiencing severe bone pain at the time of the study. Conclusions This cross-sectional, non-interventional study found high implementation of guideline-recommended BTA prescribing, good pain control and low incidence of skeletal-related events. Long-term BTA randomized controlled trials have the potential to further optimize routine care outcomes for patients.