ASCO GU 2018: Metformin and statin together may delay prostate cancer metastasis
Methods:
This population-based study includes patients identified from the SEER database linked with Medicare files diagnosed with high-risk CaP (T category ≥T2c or PSA level ≥20 ng/ml or Gleason score ≥8) between 2008-2011. Hazard ratios (HR) and 95% confidence intervals were calculated using a time-varying Cox proportional hazard model with competing causes of death.
Results:
A total of 12,700 patients were included in the analysis. Post-diagnostic use of statin and metformin was associated with a substantial reduction in CaP mortality, with more pronounced effects in obese patients (HR=0.32) or M1 disease (HR=0.54). Interestingly, effects of statins vary widely by brand, with atorvastatin being associated with the largest reduction in CaP mortality (HR=0.18, 95% 0.07-0.50).
Conclusions:
CaP mortality was substantially lower in high-risk CaP post-diagnostic users of statin within 6 years of follow-up. A synergistic effect of statin and metformin was observed in patients with M1 disease only. Prospective randomized controlled trials are required to confirm and validate these findings.
Presented by: Grace L. Lu-Yao
Written by: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre, Twitter:@GoldbergHanan at the 2018 American Society of Clinical Oncology Genitourinary (ASCO GU) Cancers Symposium, February 8-10, 2018 - San Francisco, CA