T-reg Function Changes: a Novel Immune Regulatory Effect Underlying Benefit of Statin Use on Lethal Prostate Cancer

This study is investigating whether taking simvastatin (a cholesterol-lowering medication) before prostate removal surgery can help the immune system better fight prostate cancer. Researchers will measure changes in immune cells (T-regulatory cells) in the prostate tissue removed during surgery. **You may be eligible if...** - You are a man with confirmed prostate cancer at intermediate or high risk of recurrence (based on stage, Gleason grade, or PSA level) - You have chosen to have your prostate surgically removed (prostatectomy) - You are not currently taking any statin or lipid-lowering medications **You may NOT be eligible if...** - You currently take statins, fibrates, niacin, or bile acid sequestrants (cholesterol-lowering drugs) - You take medications that interact unsafely with simvastatin (such as certain antifungals, antibiotics, or HIV drugs) - You have conditions that make simvastatin unsafe for you (liver disease, certain muscle conditions) Talk to your doctor to see if this trial is right for you.