Tobacco linked to one-third of cancer cases

Cancers that are caused by tobacco were diagnosed in 2.4 million Americans from 1999 to 2004, according to the first U.S. government study to quantify malignancies attributed to tobacco.

Researchers from the U.S. Centers for Disease Control and Prevention tallied the incidence of more than a dozen cancers linked to tobacco, including lung, bronchial, stomach, pancreatic, kidney and cervical cancer. The numbers were highest among men, Southerners and black and non-Hispanic people, the groups most likely to smoke.

Tobacco use is responsible for one-third of cancers diagnosed in America, said Matthew McKenna, director of the CDC's Office on Smoking and Health. The states with the lowest smoking rates, mainly in the West, were also those with the lowest cancer rates, the study found.

"Tobacco use is the leading preventable cause of disease and premature death in the United States and the most prominent cause of cancer," McKenna said in a statement. "If proven strategies were fully implemented to decrease tobacco use, much of the suffering and death that cancer inflects on families and communities could be prevented."

The study, published in the CDC's Morbidity and Mortality Weekly Reports Surveillance Summary, didn't look at individual tobacco use. Instead, it tallied the number of patients diagnosed with each type of cancer that has been shown to stem from tobacco use.