The use of aspirin for primary prevention of colorectal cancer: a systematic review prepared for the U.S. Preventive...

Area of Science:

• Gastroenterology
• Oncology
• Preventive Medicine

Background:

• The role of aspirin in colorectal cancer prevention remains a subject of debate.
• Understanding the balance between benefits and harms is crucial for clinical decision-making.

Purpose of the Study:

• To systematically evaluate the efficacy and safety of aspirin chemoprevention for colorectal cancer.
• To synthesize evidence from various study designs regarding aspirin's impact on adenoma and cancer incidence.

Main Methods:

• Comprehensive literature search across multiple databases (MEDLINE, EMBASE, CENTRAL) up to 2006.
• Inclusion of randomized controlled trials (RCTs), case-control, and cohort studies for efficacy.
• Systematic review of existing literature for assessment of harms.

Main Results:

• Aspirin significantly reduced colonic adenoma incidence across RCTs, case-control, and cohort studies.
• Cohort studies indicated a 22% reduction in colorectal cancer incidence with regular aspirin use.
• Benefits were more pronounced with high-dose aspirin and prolonged use (>10 years); however, gastrointestinal complications increased in a dose-related manner.

Conclusions:

• Aspirin demonstrates effectiveness in reducing colonic adenoma and colorectal cancer incidence, especially at high doses for extended durations.
• The potential for gastrointestinal harms associated with aspirin chemoprevention requires careful risk-benefit assessment.
• Further research is needed to compare the cost-effectiveness of aspirin chemoprevention against or alongside cancer screening strategies.