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Epidemiology of Cancer
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: 2009 Statistics
Estimated New Cases (excludes basal and squamous cell skin cancers and in situ carcinoma except urinary bladder)
|Prostate 192,280 (25%)||Breast 192,370 (27%)|
|Lung & bronchus 116,090 (15%)||Lung & bronchus 103,350 (14%)|
|Colon & rectum 75,590 (10%)||Colon & rectum 71,380 (10%)|
|Urinary bladder 52,810 (7%)||Uterine corpus 42,160 (6%)|
|Melanoma of the skin 39,080 (5%)||Non-Hodgkin lymphoma 29,990 (4%)|
|Non-Hodgkin lymphoma 35,990 (5%)||Melanoma of the skin 29,640 (4%)|
|Kidney & renal pelvis 35,430 (5%)||Thyroid 27,200 (4%)|
|Leukemia 25,630 (3%)||Kidney & renal pelvis 22,330 (3%)|
|Oral cavity & pharynx 25,240 (3%)||Ovary 21,550 (3%)|
|Pancreas 21,050 (3%)||Pancreas 21,420 (3%)|
|All sites 766,130 (100%)||All sites 713,220 (100%)|
|Lung & bronchus 88,900 (30%)||Lung & bronchus 70,490 (26%)|
|Prostate 27,360 (9%)||Breast 40,170 (15%)|
|Colon & rectum 25,240 (9%)||Colon & rectum 24,680 (9%)|
|Pancreas 18,030 (6%)||Pancreas 17,210 (6%)|
|Leukemia 12,590 (4%)||Ovary 14,600 (5%)|
|Liver & intrahepatic bile duct 12,090 (4%)||Non-Hodgkin lymphoma 9,670 (4%)|
|Esophagus 11,490 (4%)||Leukemia 9,280 (3%)|
|Urinary bladder 10,180 (3%)||Uterine corpus 7,780 (3%)|
|Non-Hodgkin lymphoma 9,830 (3%)||Liver & intrahepatic bile duct 6,070 (2%)|
|Kidney & renal pelvis 8,160 (3%)||Brain & other nervous system 5,590 (2%)|
|All sites 292,540 (100%)||All sites 269,800 (100%)|
By far, the number one risk factor for cancer (indeed for virtually all chronic diseases) is age. Approximately 77% 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 one person will develop cancer in his or her lifetime. For example, in the United States, the lifetime risk of developing cancer for men is less than one in two. In women, it is approximately one in three.
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.
Some risk factors are associated with multiple cancers (eg, tobacco and diet), while other risk factors are specific to one type of cancer (eg, ultraviolet radiation and skin cancer, human papillomavirus and cervical cancer). To learn more about the individual risk factors for a particular type of cancer, click on the cancer of your choice at the bottom of this page.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?
American Cancer Society. Cancer Facts & Figures 2009. Atlanta: American Cancer Society; 2009. American Cancer Society website. Available at: http://www.cancer.org/downloads/STT/500809web.pdf .
Bast RC, Kufe DW, Pollock RE, et al. Eds. Cancer Medicine . 5th ed. Hamilton, ON: Decker Inc; 2000.
Cancer. Merck Manual of Medical Information website. Available at: http://www.merck.com/mrkshared/mmanual%5Fhome/contents.jsp . Accessed March 25, 2003.
Defining cancer. National Cancer Institute website. Available at: http://www.cancer.gov/cancertopics/what-is-cancer . Accessed August 1, 2008.
Detailed guide. American Cancer Society website. Available at: http://www.cancer.org/ . Accessed August 1, 2008.
Finley RS, Balmer C. Concepts in Oncology Therapeutics . 2nd ed. Bethesda, MD: American Society of Health-System Pharmacists;1998.
Fox SI. Human Physiology . 4th ed. Dubuque, IA: William C. Brown Publishers; 1993.
- Reviewer: Igor Puzanov, MD
- Review Date: 09/2012
- Update Date: 09/26/2012