About half of all of the deaths that occur due to 12 types of cancer in people over age 35 are due to smoking cigarettes. Most of the deaths are due to the cancers of the lungs, trachea, and larynx, but half of all deaths due to bladder cancer, oral cancer, and esophageal cancer are linked to smoking cigarettes, too.
Previously, reports on the number of cancer deaths due to smoking are broken down into lung cancer and all other cancers. A study published in JAMA Internal Medicine noted that estimates of deaths due to smoking are based on data that is more than 10 years old, but that the number of people who smoked and the magnitude of the association between smoking and cancer deaths has changed since then.
By analyzing the number of deaths due to 12 cancers known to be associated with cigarette smoking, the researchers estimated that 167,805 cancer deaths out of the 345,962 cancer deaths in 2011 were associated with smoking. These are the deaths that would not have occurred if no one smoked.
The percentage of deaths due to smoking varied by the type of cancer death. Eighty percent of deaths due to lungs and trachea in 2011 were estimated to be due to cigarette smoking, as were 50% of deaths due to esophageal cancer and 45% of deaths due to bladder cancer. Smoking cigarettes caused an estimated 17% of kidney cancer deaths, 30% of stomach cancer deaths, and 22% of cervical cancer deaths, and 24% of liver and bile duct cancer deaths.
The data that was used to determine these estimates comes from national surveys and interviews that asked people about their medical histories and whether and how they used tobacco. This is one of the limitations of the study since people who take part in surveys tend to be more educated and less racially diverse than the general population, which means that the estimates may be too high. On the other hand, this study did not take into account cancers due to second-hand cigarette smoke or due to the use of other types of tobacco such as cigars, pipes, and chewing tobacco. These factors would add more cancer deaths caused by tobacco.
