Metformin and prostate cancer mortality: a meta-analysis

Area of Science:

• Oncology
• Pharmacology
• Epidemiology

Background:

• Conflicting results exist regarding metformin's impact on prostate cancer outcomes.
• Metformin is a common antidiabetic drug with potential anticancer effects.
• Understanding its role in prostate cancer is crucial for patient management.

Purpose of the Study:

• To systematically review and meta-analyze observational studies on metformin use and prostate cancer outcomes.
• To evaluate the association between metformin and overall survival, prostate cancer-specific mortality, and biochemical recurrence.
• To address confounding factors, particularly diabetes status.

Main Methods:

• Systematic literature search of PubMed and Embase databases.
• Inclusion of nine retrospective cohort studies with 9,186 patients.
• Random-effects models used to calculate pooled hazard ratios (HRs) and 95% confidence intervals (CIs).

Main Results:

• Metformin use was linked to improved overall survival (HR 0.88, 95% CI 0.86-0.90) and reduced biochemical recurrence (HR 0.79, 95% CI 0.63-1.00).
• No significant association was found with prostate cancer-specific mortality (HR 0.76, 95% CI 0.44-1.31).
• Significant heterogeneity and quality differences were noted among the included studies.

Conclusions:

• Metformin may offer benefits for diabetic men with prostate cancer, particularly regarding survival and recurrence.
• High-quality, prospective studies are required to validate these findings.
• Further research should explore metformin's generalizability to non-diabetic and diverse patient populations.