Burden of symptoms associated with development of metastatic bone disease in patients with breast cancer

Purpose: Women with breast cancer frequently develop painful bone metastases. This retrospective study was designed to longitudinally characterize patterns of patient-reported symptoms among patients with breast cancer relative to the diagnosis of bone metastases. Methods: Patient records were identified from the Oncology Services Comprehensive Electronic Records (OSCER) database which includes outpatient oncology practices across the USA. Symptom burden was assessed by Patient Care Monitor (PCM) assessments, which are administered as part of routine care in a subset of these practices. Eligible patients were women diagnosed with breast cancer (ICD-9-CM 174.xx) who developed bone metastases (ICD-9-CM 198.5) and had ≥1 PCM assessment between January 2007 and December 2012. The pre-specified endpoint was the occurrence of moderate to severe symptom burden, defined as PCM score ≥4 (0–10 scale). Results: One thousand one hundred five women (median age, 61) met the eligibility criteria. Worsening of symptoms, particularly fatigue and pain, occurred in the months leading up to the diagnosis of bone metastases. After bone metastases diagnosis, the rate of increase in the proportion of patients experiencing moderate/severe symptoms slowed, but continued to climb during follow-up. Median time to moderate/severe symptoms was 0.9 month for fatigue, 1 month for pain, 2.9 months for trouble sleeping, and 7.7 months for numbness/tingling. Half of the patients received bone-targeted agents after diagnosis of bone metastases. Conclusions: Symptom burden, especially pain and fatigue, increased both before and after the diagnosis of bone metastases, highlighting the need for proactive monitoring and management of symptoms in breast cancer patients.