Society Report Describes Historic Drop in Cancer Deaths

Article date: February 9, 2006

Special Focus: Environmental Pollutants and Cancer

A new milestone in the fight against cancer is documented in an annual American Cancer Society report released today. It shows that the actual number of Americans who died of cancer dropped below the count for the previous year, based on records from 2003 and 2002, the most recent data available. This drop in actual cancer deaths comes in spite of a larger and older US population, according to the report Cancer Facts & Figures 2006.

"For years we've proudly pointed to dropping cancer death rates even as a growing and aging population meant more actual deaths," said John Seffrin, PhD, American Cancer Society chief executive officer. "Now, for the first time, the advances we've made in prevention, early detection, and treatment are outpacing even the population factors that in some ways obscured that success."

The death rate from all cancers combined has been falling in the US since 1991, according to other reports. Death rates are considered a good measure of progress against cancer. They compare apples to apples…measuring, for example, the percentage of all men who died of prostate cancer in 2003 compared with that same measurement in 2002.

Cancer Projections for 2006

While the actual number of cancer deaths is projected to drop again in 2006, the number of new cancer cases is expected to rise in the coming year, due largely to a bigger and older US population.

The authors of Cancer Facts & Figures project that in 2006 approximately 1.4 million Americans will be diagnosed with cancer and 565,000 will die of the disease. About a third of these deaths will be related to tobacco use, and another third will be related to nutrition, physical activity, or being overweight or obese. Almost all of these deaths could be prevented.

Many cancers, such as those of the breast, colon, rectum, cervix, prostate, oral cavity, and skin can be found early with screening tests, when treatment is most likely to be effective.

Notes About Lung, Breast, Prostate, and Colon Cancers

Lung cancer is still expected to be the leading cancer killer in both men and women in 2006, with 87% of those deaths linked to smoking. The report lists 15 different types of cancer that are related to tobacco use, from nasopharynx to kidney to acute myeloid leukemia. Other highlights of the report include:

• Incidence and death rates from lung cancer continue to decrease in men. Among women the lung cancer incidence rate has leveled off but death rates continue to increase. Lung cancer remains the top cause of cancer death in the U.S, with an estimated 174,470 new cases and 162,460 deaths expected this year.
• Breast cancer remains the most common cancer other than skin cancer among women in the U.S., with an estimated 212,920 new cases and 40,970 deaths expected in 2006. Despite increasing incidence (seen mainly in older women), the death rate from breast cancer continues to fall.
• Prostate cancer is the most common cancer other than skin cancer among men in the U.S., with an estimated 234,460 new cases and 27,350 deaths expected in 2006. Although death rates have decreased since the early 1990s, rates in African-American men remain more than twice as high as rates in white men.
• Colon and rectum cancer combined are the third most common cancer in both men and women, with 148,610 new cases projected in 2006. Incidence rates decreased by 1.8% per year during 1998-2002, partly reflecting an increase in screening exams and polyp removal, which prevents polyps from turning into cancer.

"Colon cancer screening is probably one of the most underused ways to save one's life from cancer that exists," said Michael Thun, MD, vice president of epidemiology and surveillance for the American Cancer Society. He noted a rise in the use of colon cancer early detection tests is one important reason for the falling incidence rates.

"But we have a long way to go on this screening. Only about half of people are getting screened and it's low across the board but it's particularly low in people who lack health insurance and have other obstacles that make it especially hard," said Thun.

Environmental Pollutants and Cancer

A special section in Cancer Facts and Figures 2006 covers environmental pollutants (mainly air pollution) and cancer. The authors explain that scientists consider many factors to be possible environmental causes of cancer, including tobacco use, poor nutrition, inactivity, obesity, certain infectious diseases, sunlight, workplace and air pollutants, and more. "Basically everything that affects the genes you inherit from your parents," said Thun. Public interest, though, focuses more on pollutants in the air or workplace.

"Cancer researchers estimate that about 75-80% of cancer cases and deaths are due to environmental factors in the broad sense, but a much smaller percentage relates to pollutants," Thun explained.

Exposure to pollutants on the job is thought to account for about 4% of all cancer deaths; exposure to environmental pollutants (both man-made and naturally occurring) account for about 2% of cancer deaths. Together, that 6% represents approximately 33,900 deaths in the US each year.

The section describes how researchers identify and evaluate possible cancer-causing substances. It goes on to discuss asbestos and radon and how people could be exposed to unsafe levels of these air pollutants indoors.

The authors also discuss outdoor air pollutants, including fine particulates, a type of air pollution often present in urban air, which has been linked with lung cancer and more strongly with heart and lung disease.

Also included is a section on secondhand tobacco smoke. It describes the lung cancer risk from secondhand smoke, which contains more than 50 known or suspected carcinogens. And Thun added a wider perspective on the health risks to non-smokers: "Secondhand smoke, in addition to causing about 3,000 lung cancer deaths, causes heart disease. In terms of absolute numbers of deaths the estimate for heart disease is about 35,000 deaths per year.”

Looking at all environmental factors in the broadest sense, the authors noted that it is possible to change some of these factors, unlike the DNA people inherit from their parents. People can and do quit smoking, for instance, which can lower their cancer risk.

Reviewed by: Members of the ACS Medical Content Staff

ACS News Center stories are provided as a source of cancer-related news and are not intended to be used as press releases.