COLORECTAL CANCER: From Global Epidemiology and Risk Factors to Lifestyle, Microbiota, Health System Challenges

Colorectal cancer (CRC) is a major global health burden and one of the leading causes of cancer incidence and mortality worldwide, with nearly two million new cases and close to one million deaths annually. Its rising impact is driven by population aging, demographic growth, and widespread adoption of Westernized lifestyles characterized by high consumption of red and processed meats, low dietary fiber intake, physical inactivity, obesity, smoking, and alcohol use. The disease arises through a multifactorial process involving genetic susceptibility, hereditary cancer syndromes such as Lynch syndrome and familial adenomatous polyposis, and environmental exposures that interact with chronic inflammation and metabolic dysfunction. This review synthesizes current knowledge on CRC epidemiology, risk factors, clinical presentation, diagnostic pathways, and staging, alongside established treatment strategies for localized and advanced disease. Particular emphasis is placed on modifiable determinants of risk, including diet and physical activity, and their role in primary prevention and survivorship outcomes.