Before answering this question it is important to know which question you are really asking. Is it, "What is the most common cause of cancer overall?" or "What is the most common cause of cancer deaths?"
Why? If your reason for asking the question is to see if there is anything you can do to lower your risk, the second question may be most important. For example, if one cancer is more common than another but rarely causes death, and another is less common but often causes death, you may want to focus first on efforts to lower your risk of the less common but more deadly cancer.
What Is the Most Common Cancer Overall?The most common type of cancer overall is skin cancer, responsible for more than a million cases of cancer in the United States yearly. That said, non-melanoma skin cancers cause fewer than 1,000 deaths per year.
The most common cause of cancer excluding skin cancer is lung cancer. It was estimated that in 2010 there would be 220,000 new cases of lung cancer diagnosed in the United States. This is followed by prostate cancer (217,730 cases), breast cancer (209,060 cases), colon and rectal cancers (142,570 cases), and bladder cancer (70,530 cases).
What Is the Most Common Cause of Cancer Deaths?The most common cause of cancer deaths in both men and women, in the United States and worldwide, is lung cancer. It was estimated that in 2010 there would be about 157,300 deaths from lung cancer. This is greater than the number of deaths from breast cancer (41,230), prostate cancer (32,050), and colon and rectal cancers (51,370) combined. And, while many people dismiss lung cancer as a smoker’s disease, it is important to note that 10 to 20% of people diagnosed with lung cancer have never smoked, and the majority of people diagnosed with lung cancer at this time are former (not current) smokers.
Most Common Cancer in WomenIn women, breast cancer is the most common type of cancer, yet nearly twice as many women die from lung cancer as do from breast cancer.
Most Common Cancer in MenIn men, prostate cancer is the most common form of cancer diagnosed, but roughly 3 times as many men die from lung cancer as do from prostate cancer.
American Cancer Society. Cancer Facts & Figures 2010. Accessed 01/21/11. http://www.cancer.org/acs/groups/content/@nho/documents/document/acspc-024113.pdf
National Cancer Institute. Common Cancer Types. Updated 11/04/10. http://www.cancer.gov/cancertopics/types/commoncancers
National Cancer Institute. Skin Cancer. Accessed 01/21/11. http://www.cancer.gov/cancertopics/types/skin