Annual Report to the Nation on the Status of Cancer 1975-2003, With a Special Feature on Cancer Among U.S. Hispanic/Latino Populations: Questions and Answers
- Incidence rates for all forms of cancers, for all sexes and populations combined, have been stable from 1992-2003. (Question 4)
- The long-term trend in overall cancer death rates, declining since the early 1990s, continued through 2003 for all races and both sexes combined. (Question 6)
- Through 2003, prostate, lung, colon and rectum in men, and breast, lung, colon and rectum in women continue to be the leading types of cancer for incidence and mortality for each racial and ethnic group. (Questions 5 and 7)
- Latinos had lower incidence rates in 1999-2003 for most cancers, but higher rates for myeloma (in females) and cancers of the stomach, liver, kidney and cervix than non-Latino white populations. (Question 11)
1. What is the purpose of this report and who created it?
This report provides an update of cancer incidence rates (new cases), death rates, and trends in the United States. The North American Association of Central Cancer Registries (NAACCR), the Centers for Disease Control and Prevention (CDC), the American Cancer Society (ACS), and the National Cancer Institute (NCI), which is part of the National Institutes of Health, collaborated to create this report. These reports have been issued annually since 1998.
This report describes cancer incidence and death rates for Hispanic, non-Hispanic white (NHW), and non-Hispanic black populations.
2. What are the sources of the data?
Cancer mortality information in the United States is based on causes of death reported by physicians on death certificates and filed by state vital statistics offices. The mortality information is processed and consolidated in a national database by CDC through the National Vital Statistics System, which covers the entire United States.
Information on newly diagnosed cancer cases occurring in the United States is based on data collected by registries in NCI's Surveillance, Epidemiology, and End Results (SEER) Program and CDC's National Program of Cancer Registries (NPCR). NAACCR evaluates and publishes data annually from registries in both programs. Incidence rates are for invasive cancers, except for bladder cancer, which includes in situ cancer.
Long-term (1975-2003) trends for all races for all sites combined and the 15 most common cancers were based on SEER incidence data covering about 10 percent of the U.S. population. Fixed-interval trends (1995-2003) for five race/ethnic populations, (white, black, Asian/Pacific Islander race groups, and Hispanic/Latino and non-Hispanic ethnic groups regardless of race) by sex, for all sites combined and the 15 most common cancers were based on 73 percent of the U.S. population. Average-annual (1999-2003), sex-specific, and age-adjusted incidence rates were based on incidence data from 38 cancer registries, covering about 82 percent of the U.S. population, including 90 percent of the U.S. Latino population.
3. Which reporting periods were chosen as a main focus of the report?
The period from 1999 through 2003 was used for describing the cancer burden, and the period 1995 through 2003 was used for describing trends among the five major racial and ethnic populations. The period from 1975 through 2003 was chosen to represent the best perspective on long-term trends in cancer incidence and death rates among all races combined.
Update on Incidence and Mortality Trends for All Cancer Sites Combined and the Top 15 Cancers
4. What is happening with cancer incidence rates overall?
After increasing from 1975-1992, incidence rates for all forms of cancer, for all sexes and populations combined, have been stable from 1992-2003. For men, incidence rates for all cancers decreased by 4.5 percent per year from 1992-1995 and were stable from 1995-2003. For women, incidence rates for all cancers combined increased from 1987-2003 by 0.3 percent per year.
5. What is happening with incidence rates for the top 15 cancers among men and women?
Among men, incidences rates of myeloma, leukemia, and cancers of the prostate, liver, kidney, and esophagus continued to increase through 2003. Incidence rates are still decreasing for cancers of the stomach and oral cavity, lung, and more recently for colon and rectum cancer and were stable through 2003 for the remaining top 15 cancers (non-Hodgkin lymphoma, melanoma, and cancers of the bladder, pancreas, and brain). Cancer of the larynx, one of the top 15 sites for males in previous years, was replaced by myeloma in this year's ranking.
Among women, the rates for non-Hodgkin lymphoma, melanoma, leukemia, and cancers of the lung, bladder, and kidney have been increasing for 28 years. The cancer incidence rates decreased more recently for cancers of the colon and rectum, uterus, ovary, and oral cavity, while stomach and cervical cancers have been declining since 1975. The incidence rates for breast cancer stabilized from 2001-2003, ending increases begun in the 1980s. The incidence rates for pancreatic cancer also stabilized from 2000 -2003, after decreasing for 16 years. Thyroid cancer incidence rates have increased in women since 1981.
6. What is happening with cancer death rates overall?
The overall decline in cancer death rates for all race and ethnic populations, first noticed in the early 1990s, has continued through 2003. This decline was more pronounced among men (1.6 percent per year from 1993-2003) than women (0.8 percent per year from 1992-2003). Death rates are the best indicator of progress against cancer.
7. What is happening with death rates for the top 15 cancers among men and women?
From 1995-2003, death rates decreased for 11 of the 15 most common cancers in men (i.e., lung, prostate, colon and rectum, pancreas, leukemia, non-Hodgkin lymphoma, bladder, stomach, brain, myeloma, and oral cavity). Death rates increased for esophageal and liver cancers in men, but recently stabilized for kidney cancer and melanoma.
Death rates among women decreased for 10 of the 15 most common cancers (i.e., breast, colon and rectum, non-Hodgkin lymphoma, leukemia, brain, myeloma, stomach, kidney, cervix, and bladder). However, death rates were stable in women for cancers of the pancreas, ovary, and uterus and increased at varying rates for lung and liver cancers.
8. What is happening with incidence rates for breast cancer?
Breast cancer incidence rates have stabilized. Most registries in this Report, upon which the fixed-interval trends statistics are based, reported a steep decline in the number of 2003 breast cancer cases. The factors that influence breast cancer incidence are complex, including changes in reproductive risks, obesity, age-cohort effects, and the prevalence of mammography screening, among others. Recent reports hypothesize that the stabilization of breast cancer incidence may be related to the rapid discontinuation of hormone replacement therapy, a known risk factor for breast cancer. Change, even stabilization, in mammography screening prevalence also affects incidence trends. Whether this first indication of a changing trend is a real or random fluctuation cannot be determined until data reporting in the next few years is complete.
9. What is happening with incidence rates for lung cancer?
Overall, lung cancer incidence rates increased in women from 1975-2003, though the rate of increase slowed over time. In particular, this year's report suggests a small increase in female lung cancer incidence rate from 1991-2003. The increase observed during this period represents a change from last year's annual report, where rates appeared stable. From 1995-2003, rates were increasing in women 65 years and older, decreasing among women ages 45-64 years old, and stable in women younger than 45 years old. In comparison, lung cancer rates in men were decreasing in all age groups.
Cancer Among U.S. Latinos
10. What is the size of the Latino population in the U.S. and how is it growing?
According to the 2000 U.S. Census, 13 percent of the population stated they were of Hispanic/Latino origin, second in size only to the non-Hispanic white population. Latinos were the fastest growing demographic population in the U.S. From 1990 to 2000, the U.S. Hispanic population grew by 58 percent, while the total U.S. population grew by 13 percent.
11. How do cancer incidence rates differ in the Latino population compared to the non-Hispanic white population?
The report finds that for 1999 to 2003, Latinos had lower incidence rates than non-Hispanic whites (NHW) for most cancers, but were less likely than the NHW population to be diagnosed with localized stage cancers of the lung, colon and rectum, prostate, female breast, and cervix. However, Latinos also had higher incidence rates for myeloma (females) and cancers of the stomach, liver, and cervix than non-Latino white populations.
12. What is happening with cancer rates for Latino children and adolescents compared to non-Hispanic whites?
The incidence of specific cancers differed substantially among Latino and non-Latino children and adolescents. Latino boys had a higher incidence rate of Hodgkin lymphoma than non-Latino boys while all Latino adolescents had lower incidence rates than NHW adolescents. Latino boys and girls had higher incidence rates of germ cell tumors than did NHW children, an observation also seen for Latino and NHW female adolescents. Also, Latino children have higher incidence of leukemia, retinoblastoma, and osteosarcoma, than do non-Latino white children. Among the cancers that have lower incidence in Latino children and adolescents, CNS tumors, neuroblastoma, and renal tumors have lower incidence rates among those born in Central and South America compared to those born in North America.
Many questions remain unanswered regarding the development of cancer in children and adolescents, exposure differences, and genetic predisposition between Latinos and non-Latinos. The diversity and large numbers of Latino immigrants to the U.S. provide a unique opportunity to study childhood and adolescent cancers.
13. What are the possible causes of higher cancer incidence rates in Latinos?
Many types of cancers with higher incidence rates in Latinos are associated with infections: human papilloma virus (HPV) in cervical cancer; helicobacter pylori (H. pylori) in stomach cancer; and hepatitis B (HBV) and hepatitis C (HCV) in liver cancer. Explanations for these differences vary by cancer type and may include higher infection rates in the countries of origin (HPV); chronic infection (HBV and HCV); sanitary conditions (H. pylori); or varied availability and use of preventive measures. In addition, relative to the non-Hispanic white populations, the number of new cases of different types of cancers varied among four Latino groups (Mexican, Puerto Rican, Central American, and South American). Therefore, risks may be different for Latinos of different ethnicity, since not all populations share the same origins, cultural traditions, and immigration status.
14. What factors affect cancer disparities in Latino populations in comparison with non-Latino populations?
Some factors that may contribute to differences in Latino cancer rates include higher incidence of some infection-related cancers; elevated exposures to environmental risk factors in Latinos' living and work places; lower education, health literacy, and income; limited English proficiency; reduced use of screening services; limited access to health care often due to lack of insurance; and less information available regarding possible genetic predispositions. Also, this population experiences unique cultural and language barriers to health services in addition to the multitude of institutional, environmental, logistical, sociodemographic and personal barriers characteristic for all minority groups in the U.S.
15. Do Latinos have equal access to quality cancer care?
Access to quality cancer care is known to be unequal for Latinos, as compared to the non-Hispanic white population and these disparities worsen existing inequalities in cancer outcomes for Latinos. Availability of good health care is related to poverty levels. For example, the variation in incidence rates for cancers of the prostate and breast may be partly related to different rates of screening for these diseases in U.S. counties with more poverty. In addition, higher incidence rates of cancers of the liver, stomach, and cervix may be related to higher infection rates in populations of counties with higher poverty rates.
Overall, Latino men and women were more likely to be diagnosed with metastatic cancer than non-Hispanic white people, and yet Latina women are under-screened. Results of studies examining reasons for lower screening rates among Latinas vary. Some of these reasons may include financial and language barriers, extent of acculturation, and socioeconomic status. However, correlations between these factors and screening rates differ by specific ethnicity and geographic location.
Furthermore, Latinos are less likely than non-Latinos to have health care coverage, especially when they are younger than 65 years old. Hispanic persons are also much less likely to have a regular source of medical care than are non-Hispanic populations, with Latino men being the least likely.
16. How are cancer disparity issues being addressed for Latinos?
Health disparities among U.S. populations are a focus of increased research and interventions. The following organizations and initiatives are seeking to bridge cancer disparity issues in Latinos:
- "Redes En Acción: The National Latino Cancer Research Network." As one of the NCI's Community Networks Programs, Redes En Acción represents a strong effort to coalesce a broad range of forces -- NCI cancer centers, academic institutions, governmental entities, national organizations and foundations, and community-based groups -- to address diverse Latino cancer issues. Redes En Acción confronts issues by combining research, professional training, and public education. [ http://redesenaccion.org/ ]
- The Cancer Prevention and Control Research Network (CPCRN) is a national network of academic, public health, and community partnerships recently established to accelerate the adoption of evidence-based cancer prevention and control in communities. In particular, the Network engages in large-scale efforts to reach underserved populations. [ http://www.cpcrn.org/default.asp ]
- The Racial and Ethnic Approaches to Community Health (REACH) initiative is an important federal initiative that supports community coalitions in designing, implementing, and evaluating community-driven strategies to eliminate disparities experienced by Latinos and other minority populations. [ http://www.cdc.gov/reach2010/ ]
- Several other examples of national networks for community programs include the CDC's National Breast and Cervical Cancer Early Detection Program (http://www.cdc.gov/cancer/NBCCEDP/) and the National Comprehensive Cancer Control Program (http://www.cdc.gov/cancer/ncccp/). These programs have helped address disparities in breast and cervical cancer screening rates among low-income, uninsured women, including Latinas, and have supported cancer control coalitions in each state to develop and implement cancer control plans in communities across the U.S.
17. How are infection-related cancers being addressed in U.S. Hispanic populations?
Public health interventions that may reduce infection-related cancers among U.S. Hispanic populations include immunization against hepatitis B and the most common oncogenic strains of HPV, screening and counseling for hepatitis B and C, and screening for cervical cancer.
How to Read This Report
18. How are cancer incidence and death rates presented?
Cancer incidence rates and death rates are measured as the number of cases or deaths per 100,000 people per year and are age-adjusted to the 2000 U.S. standard population. When a cancer affects only one gender -- for example, prostate cancer -- then the number is per 100,000 persons of that gender. The numbers are age-adjusted, which allows for comparison of rates from different populations with varying age composition over time and regions.
19. What is an annual percent change or APC?
The annual percent change (APC) is the average rate of change in a cancer rate per year in a given time frame (i.e., how fast or slowly a cancer rate has increased or decreased each year over a period of years). Annual percent change was calculated for both incidence and death rates. The number is given as a percent, such as the approximate one percent per year decrease.
A negative APC describes a decreasing trend, and a positive APC describes an increasing trend. In this report, trends are reported as increasing and decreasing only if they are statistically significant.
20. What are proportional incidence rates and why were they used for the first time in a Report to the Nation?
Since population estimates for specific Latino population groups were not available from the U.S. Bureau of the Census by age and sex between 1999 to 2003, proportional incidence ratios (PIR) were used to compare the proportion of all cancer cases due to a specific cancer type among a specific Latino group with the corresponding proportion among non-Hispanic white people. The proportion of liver cancer was higher among all Latino groups when each was compared with NHW people; cancers of the stomach and gallbladder were proportionally higher among all groups when each was compared with the NHW population (except stomach cancer in Cuban males and gallbladder cancer in Cuban females).
21. Why were rates adjusted for delays in reporting incidence data to SEER?
This report presents analyses of long-term trends in cancer incidence rates with and without adjustment for reporting delays and more complete information. Adjusting for these delays and accumulating more complete and accurate information provides the basis for a potentially more definitive assessment of incidence rates and trends in the most recent years for which data are available. Cancer registries routinely take two to three years to compile their current cancer statistics. An additional one to two years may be required to have more complete incidence data on certain cancers, such as melanoma, prostate and breast cancers, particularly when they are diagnosed in outpatient settings. Cancer registries continue to update incidence rates to include these cases. Consequently, the initial data reported for certain cancer incidence rates may be an underestimate. Long-term reporting patterns in SEER registries have been analyzed, and it is now possible to adjust site-specific incidence rates and incidence rates for all cancers combined to correct for expected reporting delays and more complete information.
22. What is joinpoint analysis and how does it account for the different time periods used for trends analysis in this report?
Joinpoint analysis is a statistical method that describes changing trends over successive segments of time and the amount of increase or decrease within each segment. This statistical method chooses the best-fitting point or points, which are called joinpoints; these points are where the rate of increase or decrease changes significantly.
Joinpoint regression analysis involves fitting a series of joined straight lines to the age-adjusted rates, and each line segment is described by an annual percent change that is based on the slope of the line segment. Each joinpoint denotes a statistically significant change in trend. Thus, for death rates for all cancers combined in men, the slope, or trend, changes in 1995 and is reported as a 1.6 percent per year decline from 1993 to 2003. However, for women, the trend changes in 1992 and is reported as a 0.8 percent per year decline from 1992 to 2003 in this report.
Joinpoint analyses were performed for incidence and mortality trends for 1975 to 2003.
23. Where is this report published?
The report appeared online on September 6, 2006 at www.interscience.wiley.com/cancer/report2006 and will appear in the October 15, 2006 print edition of Cancer.
24. Where can I find out more about the report?
For more information, visit the following Web sites:
'Annual Report to the Nation' press release: http://cancer.gov/newscenter/pressreleases/ReportNation2006Release
For supplemental material, please go to www.interscience.wiley.com/cancer/report2006.
CDC (Division of Cancer Prevention and Control): http://www.cdc.gov/cancer
CDC (National Center for Health Statistics' mortality report): http://www.cdc.gov/nchs/about/major/dvs/mortdata.htm
Citation: Howe HL, Wu X, Ries LA, Cokkinides V, Ahmed F, Jemal A, Miller B, Williams M, Ward E, Wingo PA, Ramirez A, Edwards BK. Annual Report to the Nation on the Status of Cancer, 1975-2003, Featuring Cancer among U.S. Hispanic/Latino Populations. Cancer. October 15, 2006.