Early-Onset Colorectal Cancer: An Observational Retrospective and Prospective Multicenter Study

This study is looking at colorectal cancer (bowel cancer) that occurs in younger adults (18–40 years old) — called early-onset — to understand what makes it different from cancer diagnosed in older adults (over 60), using stored tissue samples and patient data. **You may be eligible if...** - You have been diagnosed with colorectal cancer and were either 18–40 years old at the time, or diagnosed after age 60 - You are willing to sign a consent form (if still alive) - Tumor tissue samples are available from your surgery or biopsy **You may NOT be eligible if...** - Your cancer was diagnosed between ages 41 and 60 - No tissue samples are available Talk to your doctor to see if this trial is right for you.