Multi-omic Approach to Study HDR Brachytherapy for Favorable Risk and Low Tier Intermediate Risk Prostate Cancer

This study uses multiple types of biological testing (multi-omics: genomics, proteomics, tissue analysis) to better understand how brachytherapy — a type of internal radiation placed directly near the prostate — affects prostate cancer tissue at the molecular level in men with low- to intermediate-risk prostate cancer. **You may be eligible if...** - You have favorable or intermediate-risk prostate cancer with at least a 10-year life expectancy - Your clinical stage is T1c–T2b - Your PSA is below 20 ng/mL - Your Gleason score (cancer grade) is below 8 - You are in good health (ECOG 0–1) - Low-tier intermediate risk is defined as a single risk factor (Gleason 7 (3+4) with PSA <10, or Gleason 6 with PSA 10–20) **You may NOT be eligible if...** - You have high-risk or very high-risk prostate cancer - Your PSA is 20 or above - Your Gleason score is 8 or higher - You have a life expectancy below 10 years Talk to your doctor to see if this trial is right for you.