Table 1.
Descriptive characteristics of patients with breast cancer with bone metastases by identification method
| Bone metastases confirmed in unstructured EHR ± ICD-9 198.5 | ICD-9 198.5 either in the structured EHR or claims | No ICD-9 198.5 | |
|---|---|---|---|
| N | 524 | 435 | 89 |
| Age at bone metastasis (years) | |||
| Median | 59 | 60 | 54 |
| Mean | 59 | 59 | 57 |
| Min | 23 | 23 | 29 |
| Max | 92 | 92 | 92 |
| Years from breast cancer diagnosis to bone metastases | |||
| Median | 2.8 | 3.0 | 2.4 |
| Mean | 5.2 | 5.4 | 4.0 |
| Phenotype | |||
| HR+ HER2+ | 12.2% | 12.2% | 12.4% |
| HR+ HER2− | 61.1% | 63.4% | 49.4% |
| HR− HER2+ | 4.4% | 4.4% | 4.5% |
| Triple negative | 12.8% | 11.0% | 21.3% |
| Unknown | 9.5% | 9.0% | 12.4% |
| BTA treated (ever) | 401 (76.5%) | 388 (89.2%) | 13 (14.6%) |
| Follow-up (months) | |||
| Median | 21.1 | 23.4 | 9.2 |
| Mean | 35.9 | 37.0 | 30.8 |
Abbreviations: EHR, electronic health records; ICD-9, International Classification of Diseases, ninth revision; HR, hormone receptor; HER2, human epidermal growth factor receptor 2; BTA, bone-targeting agent.