Overall cancer incidence rates declined by 0.6% per year in men and were stable in women between 2004 and 2008, while cancer death rates decreased by 1.8% per year in men and by 1.6% per year in women, according to the American Cancer Society’s annual cancer statistics report.
Over the past 10 years of available data (1999-2008), cancer death rates have declined in men and women of every racial/ethnic group except American Indians/Alaska Natives, among whom rates have remained stable, according to the Cancer Statistics 2012 report. The reduction in overall cancer death rates since 1990 in men and 1991 in women translates to the avoidance of more than a million total deaths from cancer during that time.
Among other findings in the report:
• A total of 1,638,910 new cancer cases and 577,190 deaths from cancer are projected to occur in the United States in 2012.
• Death rates continued to decline for all four major cancer sites (lung, colorectum, breast and prostate) from 1999 to 2008, with lung cancer accounting for almost 40% of the total decline in men and breast cancer accounting for 34% of the total decline in women.
• The most rapid declines in cancer death rates during the survey period occurred among African American and Hispanic men (2.4% and 2.3% per year, respectively).
• Cancer incidence and death rates varied considerably among racial and ethnic groups. For all cancer sites combined, African-American men had a 15% higher incidence rate and a 33% higher death rate than white men, whereas African-American women had a 6% lower incidence rate but a 16% higher death rate than white women.
• Compared with whites, African-American men and women have poorer survival once cancer is diagnosed. The five-year relative survival is lower in African Americans than in whites for every stage of diagnosis for nearly every type of cancer.
• Cancer incidence and death rates are lower in other racial and ethnic groups than in whites and African Americans for all cancer sites combined and for the four most common cancer sites. However, incidence and death rates for cancers related to infectious agents, such as those of the cervix, stomach and liver, are generally higher in minority populations than in whites.
Further progress can be accelerated by applying existing cancer control knowledge across all segments of the population, with an emphasis on those groups in the lowest socioeconomic bracket, according to the report.
Despite declines in incidence rates for the most common cancers, the incidence of several cancers has increased in the past decade, according to a special section that accompanies the main report. These higher rates apply to cancers of the pancreas, liver, thyroid and kidney, melanoma of the skin, esophageal adenocarcinoma and certain subsites of oropharyngeal cancer associated with human papillomavirus infection.
Researchers led by Edgar P. Simard, PhD, MPH, a senior epidemiologist with the American Cancer Society, examined trends in incidence rates from 1999 through 2008 for those cancers to detail changes by race, sex and age. They found rates for HPV-related oropharyngeal cancer, esophageal adenocarcinoma and melanoma increased only in whites, except for esophageal adenocarcinoma, which also increased in Hispanic men.
Liver cancer rates increased in white, black and Hispanic men and in black women only. In contrast, incidence rates for thyroid and kidney cancers increased in all racial/ethnic groups except American Indian/Alaska Native men.
Increases in incidence rates by age were steepest for liver and HPV-related oropharyngeal cancers among those ages 55 to 64 and for melanoma in those 65 and older. Notably, for HPV-related oropharyngeal cancer in men and thyroid cancer in women, incidence rates were higher in those ages 55 to 64 than in those ages 65 and older. Rates increased for both local and advanced stage diseases for most cancer sites.
The reasons for these increasing trends are not entirely known, according to the researchers. Part of the increase (for esophageal adenocarcinoma and cancers of the pancreas, liver, and kidney) may be linked to the increasing prevalence of obesity as well as increases in early-detection practices for some cancers. These rising trends will exacerbate the growing cancer burden associated with population expansion and aging, the researchers said, and additional research is needed to determine their underlying cause.
The American Cancer Society noted 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.
The report appears on the website of CA: A Cancer Journal for Clinicians. To read the primary report, visit http://bit.ly/xOdqhc; and to read the special section, visit http://bit.ly/yMCsBz.