Metronidazole as Preoperative Therapy in CRC / FusoMetro-001

This study is testing whether taking the antibiotic metronidazole before surgery can improve outcomes for people with colon cancer whose tumors contain a specific bacteria called Fusobacterium nucleatum, which has been linked to worse survival in colorectal cancer. **You may be eligible if...** - You are 18 or older - You have a newly diagnosed primary colorectal cancer that is more than 15 cm from the anal opening - You are a candidate for surgical removal of the tumor - You have not received any prior treatment for this cancer **You may NOT be eligible if...** - You have a known allergy to metronidazole or similar antibiotics - You have taken antibiotics in the 6 weeks before enrollment - You need emergency surgery (within 14 days) - You have had another cancer in the past 5 years (except minor skin cancers or cervical carcinoma in situ) - You are pregnant or breastfeeding - You have significant kidney, liver, or cardiovascular disease Talk to your doctor to see if this trial is right for you.