Modern aspects of the etiopathogenesis, primary prevention, and early diagnosis of colorectal cancer

This chapter summarizes current concepts in the etiopathogenesis of colorectal 
cancer, including hereditary susceptibility, the adenoma–carcinoma sequence, the 
serrated neoplasia pathway, inflammation, metabolic disturbances, and host–gut 
microbiota interactions. Modifiable risk factors and primary prevention measures are 
reviewed, including smoking cessation, dietary modification, adequate fiber intake, 
and regular physical activity. Particular attention is given to chemoprevention with 
aspirin and nonsteroidal anti-inflammatory drugs, differences in the evidence across 
average-, intermediate-, and high-risk populations, and prevention in Lynch syndrome. 
The principles of secondary prevention and early detection are discussed with regard 
to family history and hereditary cancer syndromes. Screening and pharmacological 
prevention strategies should be selected on the basis of individualized risk assessment 
and a careful balance of expected benefits and potential harms.