Biomarkers in epidemiology: scientific issues and ethical implications

Area of Science:

• Biomarkers
• Epidemiology
• Toxicology

Background:

• Current biomarkers detect xenobiotics at cellular/molecular levels, identify early disease changes, and map exposure-disease continuums.
• These advanced capabilities differentiate them from previous generations.

Purpose of the Study:

• To outline the essential characteristics of biomarkers for enhancing cancer epidemiology.
• To emphasize the need for validation, reliability, and practicality in biomarker application.

Main Methods:

• Discussion of biomarker characteristics: sensitivity, early detection, and continuum identification.
• Highlighting the necessity of pilot studies and interdisciplinary collaboration.
• Addressing validation requirements: background prevalence, sample size, natural history, persistence, variability, confounding factors, and predictive value.

Main Results:

• Biomarkers must be valid, reliable, and practical for epidemiological use.
• Laboratory-developed biomarkers often lack field validation.
• Validation requires addressing numerous population-specific issues and practical considerations.

Conclusions:

• Biomarker utility in epidemiology depends on reducing misclassification and improving exposure-disease association interpretation.
• Effective biomarker use enhances opportunities for disease prevention.
• Validation and research carry clinical, ethical, and legal implications.