Skin cancer: Primary, secondary, and tertiary prevention. Part I.

Skin cancer is the most commonly diagnosed cancer worldwide. Understanding the natural history of skin cancer provides the framework for the creation of prevention and control strategies that aim to reduce the skin cancer burden. Based on the target (individual vs population), disease stage, and risk factors (modifiable vs nonmodifiable), strategies can be categorized into 4 levels-health promotion (also known as primordial prevention), primary prevention, secondary prevention, and tertiary prevention.