Report to the Nation: U.S. Latinos and Cancer
The overall decline in cancer death rates in the United States, a trend first reported in the early 1990s, continued through 2003, according to the Annual Report to the Nation on the Status of Cancer, published online September 6 in Cancer.
The report provides updated statistics on cancer rates and trends from 1975 through 2003. It features a special section on cancer among Hispanic/Latino populations living in the United States.
Overall cancer incidence rates (the rates at which new cancers are diagnosed) have been stable for both sexes and all races combined from 1992 through 2003.
For men, the overall incidence rates were stable from 1992 through 2003, but the same rates for women increased from 1979 through 2003, due in part to small but persistent increases in lung cancer. This year, however, there was some apparent good news.
"The rate of new cases of female lung cancer is still increasing, but the rates of increase are slowing down," says lead researcher Dr. Holly L. Howe of the North American Association of Central Cancer Registries, Inc. (NAACCR).
Another change is that incidence rates for breast cancer have stabilized, ending a rise that began in the 1980s. The researchers will not know for several years whether this indication of a changing trend is a true reversal or a random fluctuation.
The incidence rate of thyroid cancer among women has doubled several times since 1981. The increases may reflect improvements in the detection of the disease, but changes in risk factors may also play a role, the researchers say.
In contrast, many cancer types have declining death and incidence rates, which the researchers attribute in part to successful cancer prevention efforts to reduce exposure to tobacco and other cancer risk factors.
"The statistics for cervical cancer are remarkable, in that both incidence and death rates have been decreasing for all racial and ethnic groups since 1975," the researchers write.
Improvements in screening have "had a measurable impact on this disease," but not all women have benefited equally, the report notes. In fact, disparities prevail among women of different socioeconomic backgrounds.
Disparities are a focus of the report's special section, which is the most comprehensive collection of cancer information about the nation's rapidly growing Hispanic/Latino populations.
"The report covers almost all of the Latino population in the U.S. and is really the first of its kind," says Dr. Howe.
Latinos had lower incidence rates for most cancers from 1999 to 2003 compared with non-Latino white populations, but had higher rates for myeloma (in females) and cancers of the stomach, liver, kidney, and cervix.
The report, which will appear in print in the October 15 Cancer, confirms previous findings that cancer is frequently discovered late in Latinos.
"Latino patients are often diagnosed in the later stages of disease, when there are fewer treatment options," says co-author Dr. Amelie Ramirez of Baylor College of Medicine.
Many of the cancers with higher incidence rates in Latinos have infectious origins, including cervical cancer (human papillomavirus virus, or HPV) and stomach cancer (Helicobacter pylori).
On the other hand, U.S. Latinos have low rates of several cancers that are common in affluent, industrialized countries where smoking, obesity, and physical inactivity are prevalent.
The report emphasizes that not all Latino populations are alike. The findings suggest that it may not be possible to compare studies on Latino populations if the populations do not share the same origins, cultural traditions, and immigration status.
By 2050, Latino populations will have contributed significantly to the growth of the U.S. population. In order to develop national strategies for controlling cancer, accurate information about the disease in these groups is needed, the researchers conclude.
The report covers 100 percent of the U.S. population for mortality, 10 percent for long-incidence trends, 73 percent for the most recent 8-year incidence trends, and 82 percent for current-incidence rates. The data are analyzed by racial and ethnic categories.
The researchers combined information from cancer registries throughout the U.S. that also participate in NCI's Surveillance, Epidemiology, and End Results (SEER) Program and/or the National Program of Cancer Registries, supported by the Centers for Disease Control and Prevention (CDC).
First published in 1998, the report is produced by the American Cancer Society, CDC, NAACCR, and NCI.
"This report pulls together a tremendous amount of information, and it should be viewed as a reference document where people can go to find the latest information on cancer," says co-author Dr. Brenda K. Edwards of NCI's Division of Cancer Control and Population Sciences.
By Edward R. Winstead