Epidemiology refers to the branch of medicine that deals with the study of the causes, distribution, and control of disease in populations. In this section we will discuss the most commonly diagnosed and most fatal types of cancer in the United States.
Epidemiology of Cancer: 2015 Statistics
By far, the number 1 risk factor for cancer (indeed for virtually all chronic diseases) is age. Nearly 78% of all cancers are diagnosed in people 55 years of age or older. Cancer researchers describe the risk of cancer in a number of ways:
Lifetime risk refers to the probability that any 1 person will develop cancer in their lifetime. For example, in the United States, the lifetime risk of developing cancer for men is less than 1 in 2. In women, it is approximately 1 in 3.
Relative risk measures the degree of the relationship between a particular risk factor and a particular cancer. Relative risk is expressed as a ratio of the number of cancer cases in a group of individuals with a risk factor over the number of cases in those without it. Most relative risks are small. For example, women who have a mother, sister, or daughter with breast cancer have about a 2-fold increased risk of developing breast cancer compared to women with no such family history of breast cancer. Other risk factors make more of an impact. One in particular, smoking, increases the risk of many cancers, but none as much as lung cancer. Men and women who smoke carry a 25-fold increased risk of lung cancer development.
Some risk factors are associated with multiple cancers (tobacco and diet), while other risk factors are specific to 1 type of cancer (ultraviolet radiation and skin cancer, human papillomavirus and cervical cancer).How do normal cells grow and develop?What is the difference between a noncancerous and a cancerous tumor?How do cancerous cells grow and develop?What is a cancer gene? How do they occur?What causes cancer?What are the different types of cancer?
- Reviewer: Mohei Abouzied, MD
- Review Date: 01/2016 -
- Update Date: 05/07/2015 -