American Cancer Society report finds continued progress in reducing cancer mortality
A steady reduction in overall cancer death rates translates to the avoidance of about 898,000 deaths from cancer between 1990 and 2007, according to the latest statistics from the American Cancer Society. However, the report, Cancer Statistics 2011, and its companion consumer publication Cancer Facts & Figures 2011 find that progress has not benefitted all segments of the population equally. A special section of the report finds cancer death rates for individuals with the least education are more than twice those of the most educated and that closing that gap could have prevented 37% -- or 60,370 -- of the premature cancer deaths that occurred in 2007 in people ages 25-64 years.
Each year, the American Cancer Society estimates the numbers of new cancer cases and deaths expected in the United States in the current year and compiles the most recent data on cancer incidence, mortality, and survival based on incidence data from the National Cancer Institute, Centers for Disease Control and Prevention, and the North American Association of Central Cancer Registries, and mortality data from the National Center for Health Statistics.
A total of 1,596,670 new cancer cases and 571,950 deaths from cancer are projected to occur in the U.S. in 2011. Overall cancer incidence rates were stable in men in the most recent time period after decreasing by 1.9% per year from 2001 to 2005; in women, incidence rates have been declining by 0.6% annually since 1998. Overall cancer death rates, which have been dropping since the early 1990s, continued to decrease in all racial/ethnic groups in both men and women since 1998 with the exception of American Indian/Alaska Native women, among whom rates were stable. African American and Hispanic men showed the largest annual decreases in cancer death rates during this time period, 2.6% and 2.5%, respectively. Lung cancer death rates showed a significant decline in women after continuously increasing since the 1930s.
Cancer Statistics 2011 is published early online in CA: A Cancer Journal for Clinicians. Other highlights of the report include:
- Among men, cancers of the prostate, lung and bronchus, and colorectum account for more than half (about 52%) of all newly diagnosed cancers. Prostate cancer alone accounts for 29% (240,890) of incident cases in men.
- The three most commonly diagnosed types of cancer among women in 2011 are breast, lung and bronchus, and colorectum, accounting for about 53% of estimated cancer cases in women. Breast cancer alone is expected to account for 30% (230,480) of all new cancer cases among women.
- The lifetime probability of being diagnosed with an invasive cancer is higher for men (44%) than women (38%).
- It is estimated that about 571,950 Americans will die from cancer, corresponding to over 1,500 deaths per day.
- Cancers of the lung and bronchus, prostate, and colorectum in men, and cancers of the lung and bronchus, breast, and colorectum in women continue to be the most common causes of cancer death. These four cancers account for almost half of the total cancer deaths among men and women.
- Lung cancer is expected to account for 26% of all cancer deaths among women in 2011.
- The lung cancer mortality rate in women has finally begun to decline, more than a decade later than the decline began in men. The lag in lung cancer trends in women compared with men reflects a later uptake of cigarette smoking in women, among whom smoking peaked about 20 years later than in men.
- Recent rapid declines in colorectal cancer incidence rates largely reflect increases in screening that can detect and remove precancerous polyps.
- The overall cancer death rate decreased by 1.9% per year from 2001-2007 in males and by 1.5% in females from 2002-2007, compared to smaller declines of 1.5% per year in males from 1993-2001 and 0.8% per year in females from 1994-2002.
- Between 1990/1991 and 2007, cancer death rates decreased by 22.2% in men and by 13.9% in women.
- Mortality rates have continued to decrease for colorectum, female breast, and prostate cancers.
- Among men, the reduction in death rates for lung, prostate, and colorectal cancers account for nearly 80% of the total decrease in the cancer death rate, while among women, a reduction in death rates for breast and colorectal cancers account for almost 60% of the decrease.
"The nearly 900,000 cancer deaths avoided over a 17-year period stand in stark contrast to the repeated claim that cancer death rates have not budged," said John R. Seffrin, Ph.D., chief executive officer of the American Cancer Society and its advocacy affiliate, the American Cancer Society Cancer Action Network (ACS CAN). "Nonetheless, we refuse to be satisfied, and are committed to doing whatever it takes, not only to ensure cancer death rates continue to drop, but to accelerate the decline."
The reports feature a Special Section on the impact of eliminating disparities on cancer deaths. Level of education is often used as a marker of socioeconomic status. In 2007, cancer death rates in the least educated segment of the population were 2.6 times higher than those in the most educated. This disparity was largest for lung cancer, for which the death rate was five times higher in the least educated than for the most educated. Differences in lung cancer death rates reflect the striking gradient in smoking prevalence by level of education; 31% of men with 12 or fewer years of education are current smokers, compared to 12% of college graduates and 5% of men with graduate degrees.
The special section also estimated the numbers of potential premature cancer deaths that could be avoided in the absence of socioeconomic and/or racial disparities. If all adults ages 25 to 64 in the United States in 2007 had the cancer death rate of the most educated non-Hispanic whites, 37% --or 60,370 out of 164,190premature cancer deaths could potentially have been avoided. For African Americans, closing the gap between death rates among the most and least educated could potentially avert twice as many premature cancer deaths as eliminating racial disparities between blacks and whites, underscoring the preponderance of poverty in cancer disparities across all segments of the population.
The annual reports have become critical tools for scientists, public health experts, and policymakers in assessing the current burden of cancer. These estimates are some of the most widely quoted cancer statistics in the world. The Society's leading team of epidemiologic researchers, in collaboration with scientists from the National Cancer Institute, compiles and analyzes incidence and mortality data to estimate the number of new cancer cases and deaths for the current year nationwide and in individual states.
The expected numbers of new cancer cases and cancer deaths should be interpreted with caution because these estimates are based on statistical models and may vary considerably from year to year. Not all changes in cancer trends can be captured by modeling techniques and sometimes the model may be too sensitive to recent trends, resulting in over- or under-estimates. For these reasons, the estimates should not be compared from year-to-year to determine trends; age-standardized cancer incidence and death rates are the best way to monitor changes in cancer occurrence and death. Despite these limitations, the American Cancer Society's estimates of the number of new cancer cases and deaths in the current year provide reasonably accurate estimates of the burden of new cancer cases and deaths in the United States. Such estimates will assist in continuing efforts to reduce the public health burden of cancer.