Cancer Death Rates Cease Decline

< Apr. 23, 2008 > -- Declining cancer death rates in the US appear to have halted, according to a new annual report from the American Cancer Society (ACS).

The report, Cancer Prevention & Early Detection Facts and Figures 2008 (CPED), points out that drops in smoking appear to have leveled off and that mammography rates have been stable or slightly declining since 2000 after increasing for more than a decade.

"We've run into plateaus in terms of people smoking and getting necessary screening. The next big barrier is the obesity epidemic," says Dr. Jay Brooks, chairman of hematology/oncology at Ochsner Health System in Baton Rouge, La.

Nevertheless, Dr. Brooks stresses, the progress already made is substantial. "When you step back and think about where we've come in this country, it's phenomenal," he says.

"The report is a tremendous example of the work that's been done over the past 20 years in showing that the efforts to reduce smoking and increase screening have been tremendous in terms of decreasing death rates from cancer," he continues.

CPED, published annually since 1992, is the most comprehensive annual report on factors that affect cancer risk, including behavior and early detection. It details the challenges and opportunities in preventing cancer and cancer death, and outlines lifestyle changes and medical care changes that have the potential to prevent about half of cancer deaths.

Report Highlights

Some findings from the report include:

About 40 percent of the reduction in cancer deaths in males between 1991 and 2003 can be attributed to declines in smoking that have taken place over the last century. But efforts have stalled: Almost 24 percent of men and 18 percent of women smoke, a rate that has remained unchanged for the past two years.

The percentage of high school students who smoke (currently 23 percent) has also leveled off since 2005.

According to the US Centers for Disease Control and Prevention (CDC), if all state tobacco control programs were funded at their recommended level for five years, there would be about 5 million fewer smokers in the United States. But in 2008, only three states (Maine, Colorado and Delaware) met or exceeded CDC minimum recommended levels for funding of these programs.

The rate of mammography screening has remained stagnant since 2000. In 2005, about two-thirds of women aged 40 and older reported having had a mammogram within the past two years (four percentage points lower than in 2000) and only 51.2 percent reported having had a mammogram within the past year. Women without health insurance and recent immigrants had the lowest levels of screening.

Rates of colorectal cancer screening are improving, but still leave ample room for improvement. Less than half (46.8 percent) of American men and women aged 50 and over have had a recent colorectal cancer screening test, up from 42.5 percent in 2000. So far, 22 states plus the District of Columbia have legislation in place that requires coverage for all colorectal cancer screening tests. Again, the uninsured and recent immigrants were least likely to have been screened.

Exposure to sunlight (outside or in the tanning booth) remains a major risk factor for different types of skin cancer. According to the report, 68.7 percent of youth reported getting sunburned during the summer, although only one-third reported using sunscreen all the time or often, not to mention other forms of protection (such as seeking shade or wearing long-sleeved clothing).

Overweight and obesity are significant risk factors for different types of cancer. Currently, 17.1 percent of adolescents and 35.2 percent of adults are considered obese. These startling figures go hand-in-hand with relatively low levels of physical activity (less than 36 percent of U.S. residents were physically active for at least 60 minutes on most days of the week, while 23.9 percent of adults reported no leisure-time physical activity) and poor eating habits (only one in five U.S. high school students and less than one-quarter of adults ate vegetables and fruits five or more times a day in 2005).

More Effort Needed for Cancer Prevention

The trends, detailed in the CPED, do point to a need for more effort.

"If we see sustained declines in prevention and early detection efforts that could really have, down the road, an impact on [cancer deaths], that's why we're picking up the pace now and emphasizing the importance so we can correct this," says study co-author Vilma Cokkinides, Ph.D., strategic director in risk factor surveillance, department of epidemiology and surveillance at the ACS in Atlanta.

Earlier this year, the ACS reported that death rates in the United States had dropped by 18.4 percent in men and 10.5 percent in women since the early 1990s, when mortality rates first began to decline. This means a total of more than half a million deaths from cancer have been averted in those years.

Dr. Otis W. Brawley, national chief medical officer of the ACS says, "If we want these gains to continue, we need comprehensive, systematic efforts to reduce tobacco use, to address the epidemic levels of obesity in this country, and to make sure all Americans have access to and receive established cancer screening tests."

Always consult your physician for more information.

More About Cancer

Cancer is not just one disease but rather a group of diseases, all of which cause cells in the body to change and grow out of control. Cancers are classified either according to the kind of fluid or tissue from which they originate, or according to the location in the body where they first developed. In addition, some cancers are of mixed types.

There is no one single cause for cancer. Scientists believe that it is the interaction of many factors together that produces cancer. The factors involved may be genetic, environmental, or constitutional characteristics of the individual.

Diagnosis, treatment, and prognosis for childhood cancers are different than for adult cancers. The main differences are the survival rate and the cause of the cancer.

The survival rate for childhood cancer is about 79 percent, while in adult cancers the survival rate is 66 percent. This difference is thought to be because childhood cancer is more responsive to therapy, and a child can tolerate more aggressive therapy.

Childhood cancers often occur or begin in the stem cells, which are simple cells capable of producing other types of specialized cells that the body needs. A sporadic (occurs by chance) cell change or mutation is usually what causes childhood cancer.

In adults, the type of cell that becomes cancerous is usually an "epithelial" cell, which is one of the cells that line the body cavity, including the surfaces of organs, glands, or body structures, and cover the body surface. Cancer in adults usually occurs from environmental exposures to these cells over time. Adult cancers are sometimes referred to as "acquired" for this reason.

Some cancers, particularly in adults, have been associated with certain risk factors. A risk factor is anything that may increase a person's chance of developing a disease. A risk factor does not necessarily cause the disease, but it may make the body less resistant to it.

Persons who have an increased risk of developing cancer can help to protect themselves by scheduling regular screenings and check-ups with their physician and avoiding certain risk factors. Cancer treatment has been proven to be more effective when the cancer is detected early.

The discovery of certain types of genes that contribute to cancer has been an extremely important development for cancer research. Over 90 percent of cancers are observed to have some type of genetic alteration. A small percentage (5 percent to 10 percent) of these alterations are inherited, while the rest are sporadic, which means they occur by chance or occur from environmental exposures (usually over many years).

Usually the number of cells in any of our body tissues is tightly controlled so that new cells are made for normal growth and development, as well as to replace dying cells. Ultimately, cancer is a loss of this balance due to genetic alterations that "tip the balance" in favor of excessive cell growth.

Always consult your physician for more information.