To explore the features of incidence proportions and long-term survivals of breast cancer patients with bone metastasis when first diagnosed.
Data were extracted from the Surveillance, Epidemiology, and End Results (SEER) database of the National Cancer Institute. Stratifications were made according to molecular subtype, age, sex, race and other factors. We performed multivariable logistic and Cox regression analysis to detect predictors of occurrence of bone metastasis at first diagnosis and factors related to all-cause mortality.
We identified 310789 patients with breast cancer within the study period. Approximately 3.6% patients were diagnosed as bone metastasis within the entire cohort and 50.5% of the metastasis cohort. The highest incidence was from the cohorts of HR+/HER2+ (5.0% of the entire cohort). N3, metastases to brain, lung and liver were associated with higher possibility of developing bone metastases. For survival, HR+/HER2+ experience the longest survival time (41 months) and triple-negative patients had the shortest survival period (10 months). lymph node status other than N0 and distal metastasis to brain, lung and liver as possible factors which were associated with higher all-cause mortality.
We recommend routine bone screen at first diagnosis within high risk patients.