Management strategies and clinical outcomes in breast cancer patients who develop left ventricular dysfunction during trastuzumab therapy

Competing risk analysis of cardiovascular death in breast cancer: evidence from the SEER database

Background

Cardiovascular disease (CVD) is the leading cause of death for all non-cancer deaths among breast cancer (BC) patients. The aim of this study was to investigate the risk of cardiovascular mortality (CVM) in patients with BC.

Methods

Patients diagnosed with primary BC between 2010 and 2018 were identified through the Surveillance, Epidemiology and End Results (SEER) database. The standardized mortality ratio (SMR) for CVD was calculated to compare the CVM of BC patients with that of the general population. Multivariate competing risk models were performed to identify predictors of CVM in BC patients.

Results

Overall, 399,014 BC patients were included from the SEER database, of whom 7,023 (1.8%) suffered death from CVD. The significantly higher overall SMR of CVM was observed in BC patients [SMR =4.84, 95% confidence interval (CI): 4.72-4.95]. Multivariate competing risk regression analysis revealed that age, race, American Joint Committee on Cancer (AJCC) stage, year of diagnosis, estrogen receptor (ER) status, progesterone receptor (PR) status, human epidermal growth factor receptor 2 (HER2) status, BC subtype, surgery, chemotherapy, radiation therapy, and median household income as independent predictors of CVM in BC patients.

Conclusions

Compared to the general population, BC patients have a higher risk of experiencing CVM during the follow-up period after diagnosis. Early detection and intervention of cardiovascular risk factors would improve overall survival (OS) of BC patients.