Relationship between bisphosphonate use and risks of recurrence and mortality among hormone receptor–positive and triple‐negative breast cancer patients
Liuye Huang, Linda S. Cook, Mei‐Tzu C. Tang, David R. Doody, Ulrike Peters, Wei Sun, Jeroen R. Huyghe, Kathleen E. Malone, Christopher I. LiAbstract
Background
Bisphosphonates (BPs) are routinely used as an adjuvant therapy for breast cancer to reduce the risk of bone recurrences given their anti‐resorptive effects on bones and antitumor characteristics. However, there remains limited evidence regarding their utility across different subtypes.
Methods
In this population‐based cohort study, the authors assessed the effects of pre‐ and post‐diagnostic BP use on recurrence, any second breast cancer event, all‐cause mortality (ACM), and breast cancer–specific mortality (BCSM) using multivariable‐adjusted Cox proportional hazards models among hormone receptor–positive (HR+) and triple‐negative breast cancer (TNBC) participants.
Results
This study enrolled 2260 HR+ and 1436 TNBC participants. The median age and follow‐up time to death was 51 and 52 years old and 168.3 and 147 months in the two subtypes, respectively. Post‐diagnostic BP use for at least 1 year was protective for ACM (hazard ratio [HR], 0.67; 95% confidence interval [CI], 0.49–0.93) and BCSM (HR, 0.54; 95% CI, 0.33–0.89) compared to never users in HR+ cases. Among participants who initiated BP after diagnosis only, a lower point estimates on the clinical outcomes were observed across both subtypes, reaching statistical significance for BCSM (HR, 0.62; 95% CI, 0.39–0.98) in HR+ cases. Among TNBC cases who continued BP use post‐diagnosis, increased risks of recurrence (HR, 3.43; 95% CI, 1.67–7.07) and BCSM (HR, 2.54; 95% CI, 1.24–5.19) were observed.
Conclusions
Although this study confirmed the protective effects of post‐diagnostic BP use on risks of mortality among HR+ cases, further studies are required to prove the effects of post‐diagnostic BP use among TNBC participants.