In the U.S., about 10% of colorectal cancer cases are diagnosed in people under 50 – and rates are rising one to two percent each year. What’s behind this trend: lifestyle, genetics, or environment? We spoke with Andrea Cercek, MD, physician-scientist and medical oncologist, about her groundbreaking clinical trial that revolutionized treatment for early-stage rectal cancers. She discusses the multifactorial causes behind these rising diagnoses, from diet and lifestyle to environmental exposures and medications, and why screening, symptom awareness, and healthy habits like exercise and stress management are critical.