The nation needs new strategies to prevent cancer and, when cancer occurs, to catch it at its earliest stages. Smoking, unhealthy diet, obesity, sedentary lifestyles, and failure to get screened all contribute to the excess burden of cancer. Failure to implement proven methods of cancer prevention leads to avoidable disease and death. A 19 percent decline in the rate at which new cancer cases occur and a 29 percent decline in the rate of cancer deaths could potentially be achieved by 2015 if efforts to help people change their behaviors that put them at risk were stepped up and if behavioral change were sustained. This would equate to the prevention of approximately 100,000 cancer cases and 60,000 cancer deaths each year by the year 2015 (Byers et al., 1999). The possible reductions in cancer incidence are particularly striking for certain cancers: accelerated changes in risk behavior could halve the number of smoking-related cancers such as lung cancer and reduce the numbers of cases of colorectal cancer by up to one-third.
To save the most lives from cancer, health care providers, health plans, insurers, employers, policy makers, and researchers should be concentrating their resources on helping people to stop smoking, maintain a healthy weight and diet, exercise regularly, keep alcohol consumption at low to moderate levels, and get screened for breast, cervical, and colorectal cancer. The health benefits of such behavioral changes extend beyond cancer to cardiovascular disease and diabetes as well. Such efforts may also help alleviate the disproportionate burden of cancer borne by members of racial and ethnic minority groups.
Many of the behaviors that place individuals at risk for cancer are well recognized, and calls for behavioral change are not new. What is new is the growing body of evidence confirming the effectiveness of interventions to help people improve their health-related behaviors. Health care providers can boost quit rates among their patients who smoke by adhering to smoking cessation guidelines. Administrators can improve the use of screening tests among health plan members by having systems in place to remind physicians and patients of needed tests. Communities can enact policies to curb exposure to secondhand smoke, limit access to tobacco products by teenagers, and create safe places for physical activity. Each of these strategies works, but especially effective in bringing about behavioral change is the simultaneous action of several parties: health care providers, administrators, educators, and policy makers.
Although personal experience illustrates for most people the great difficulty of achieving sustained behavioral change, Americans have made substantial improvements in their health habits in the past few decades. There has been, for example, a steep decline in the number of Americans who smoke; there have been some improvements in diet; and screening for some cancers is widespread. Investment in the effective clinical and public health tools at hand can produce much greater improvements.
In this report, the National Cancer Policy Board reviews the evidence that cancer incidence rates can be dramatically reduced and outlines a national strategy to realize the promise of cancer prevention and early detection. The report examines
the extent to which the burden of cancer could be reduced through cancer prevention and early detection;
the effectiveness of cancer screening methods and interventions to alter smoking, eating, and exercise habits;1
approaches to enhancing the potential benefits of proven interventions;
a case study of screening for lung cancer, illustrating the problem of adopting new technology when the science is uncertain;
professional education and training needs;
federal and state programs that support cancer prevention and early detection; and
research trends and opportunities.
The Board recommends that the following steps be taken to increase the rates of adoption, the reach, and the impacts of evidence-based cancer prevention and early detection interventions.
Recommendation 1: The U.S. Congress and state legislatures should enact and provide funding for enforcement of laws to substantially reduce and ultimately eliminate the adverse public health consequences of tobacco use and exposure.
Tobacco is the greatest contributor to deaths from cancer, and reduction in tobacco use offers the greatest opportunity to reduce the incidence, morbidity, and mortality of cancer. Specific actions that would be effective include the following:
Taxation is the single most effective method of reducing the demand for tobacco. States should set sufficiently high levels of excise taxation on tobacco products to discourage tobacco use, but levels should not be so high that they encourage significant tax avoidance activities.
States should allocate sufficient funds from the Tobacco Master Settlement Agreement and tobacco excise taxes to support comprehensive, state-based tobacco control efforts consistent with guidelines of the Centers for Disease Control and Prevention.
States should improve compliance with the provisions of the 1992 Synar amendment, which requires that states have sales-to-minor rates of no greater than 20 percent in order to receive federal Substance Abuse Prevention and Treatment Block Grant awards. By 2000, only 25 states had achieved this level of compliance.
States should impose tobacco-licensing requirements for merchants selling tobacco products, as recommended in the 2000 report of the Surgeon General (U.S. Department of Health and Human Services and Office of Disease Prevention and Health Promotion, 2000). The threat of revocation of the license as a consequence of selling tobacco products to minors could provide a strong incentive for merchants to comply with existing laws. Further, requiring that merchants pay for a license to sell tobacco could provide needed funds for monitoring and enforcement.
Internet sales of tobacco products are not covered by the Synar amendment, which leaves a significant opening for minors to have access to tobacco. More than 90 websites sell cigarettes in the United States, and the number is expected to grow. Congress should therefore act to prohibit the promotion, sale, and distribution of tobacco products over the Internet to individuals under the age of 18.
Regulations at the state level vary greatly across the country. Until the passage of federal legislation, state and local legislatures should increase
their regulatory efforts related to environmental tobacco smoke by establishing smoke-free indoor workplaces, public buildings, and restaurants.
Further restrictions are needed to reduce tobacco promotion and advertising, which compromises youth tobacco prevention efforts. Restrictions now in place include a mix of voluntary agreements, restrictions resulting from settlements of lawsuits, and prohibitions defined by state or local ordinances, but some efforts have been hampered by protection of commercial speech. The Board urges renewed national consideration of how to address the practices of placing advertising at convenience stores and in magazines that are particularly attractive to minors, and tobacco sponsorship of youth-oriented events.
Recommendation 2: A national strategy should be developed and coordinated by the U.S. Department of Health and Human Services to address the epidemic of obesity, unhealthy diet, and physical inactivity in America, which are all significant risk factors for cancer and other diseases. Effective interventions need to be identified and broadly applied to reduce cancer risk among the general population and among populations at higher risk.
Dietary interventions to prevent cancer have, to date, focused primarily on particular components such as the consumption of fruits and vegetables, fiber, and fats. Obesity and physical inactivity have recently joined unhealthy diet as leading risk factors for cancer.
Efforts to maintain a healthy weight that start early in childhood and continue throughout adulthood are likely to be more successful than efforts to achieve and maintain weight loss once obesity is established. Over time, even a small decrease in the numbers of calories consumed and a small increase in physical activity can help prevent weight gain or facilitate weight loss.
Worksite fitness programs have resulted in increased levels of physical activity among employees, and it is recognized that environmental policies related to zoning, land use, safety, and transportation greatly affect opportunities for exercise. Among youth, school policies regarding healthy school lunches, physical education requirements, and the availability of after-school recreational programs improve nutrition and affect rates of participation in exercise.
The National Cancer Policy Board endorses the comprehensive Recommendations for Public Health Action on Weight Control and Physical Activity to Promote Cancer Prevention proposed by the International Agency for Research on Cancer, an agency within the World Health Organization (International Agency for Research on Cancer, 2000) (see Box 11.3 in Chapter 11). These recommendations could serve as a basis for the formulation of a national strategy through the Office of Disease Prevention and Health Promotion.
Recommendation 3: The U.S. Congress should provide sufficient appropriations to the Centers for Disease Control and Prevention to support innovative public and private partnerships to develop, implement, and evaluate comprehensive community-based programs in cancer prevention and early detection. Every state should have and implement a comprehensive cancer control plan.
The Centers for Disease Control and Prevention (CDC) is the federal link to the nation’s public health infrastructure, principally through state and local health departments. State efforts in cancer prevention and early detection are in many cases piecemeal and are organized around categorically funded programs. CDC needs to build the capacities of states—and, in turn, their local partners—to develop and implement comprehensive cancer control plans.
CDC’s National Comprehensive Cancer Control Program defines cancer control plans as those with an integrated and coordinated approach to reduce the rates of incidence, morbidity, and mortality of cancer through prevention, early detection, treatment, rehabilitation, and palliation (www.cdc.gov/cancer/ncccp/index.htm). Roughly half of the states (27 states) report having a comprehensive cancer control plan, but the plans are in various stages of implementation. CDC supports states in developing and implementing such plans, but the available support has been modest (approximately $37 million since 1998). The CDC estimates that $30 million per year would be needed for states to have plans developed and implementation in progress by 2005 (Leslie Given, Division of Cancer Prevention and Control, CDC, personal communication to Maria Hewitt, IOM, September 9, 2002).
State and local health departments, in partnership with private organizations, can play important roles in instituting and coordinating comprehensive cancer prevention programs. Health departments can, for example:
monitor and publicize state trends in cancer and cancer-related behaviors;
support media campaigns to promote healthy behaviors;
target interventions to low income and racial/ethnic groups at high risk for cancer, e.g., by providing breast, cervical, and colorectal cancer screening services to medically uninsured and medically underserved populations;
develop and distribute best-practice guidelines to major employer human resources departments to encourage smoking cessation programs, wellness programs, on-site healthy eating and exercise facilities, flexible time for employees to allow alternative means of commuting (e.g., by bicycle or foot), and use of preventive health services (e.g., screening and smoking cessation programs);
collaborate with school systems to develop cancer prevention-related educational curricula and programs;
collaborate with public and private organizations to provide incentives for physical activity, healthy eating, and participation in weight loss programs (e.g., reduced fees for fitness clubs, on-site weight control groups, employer nonautomotive commuting programs);
track state use of funds available through the 1998 Transportation Equity Act for the 21st Century (Public Law 105-178), which provides federal funds to construct sidewalks and bicycle trails and to integrate mass transit, roads, and pedestrian and bicycle facilities into a comprehensive transportation plan;
support free and reduced-fee health clinics organized through local health departments and other community-based programs; and
evaluate the effectiveness of services and programs.
Recommendation 4: Public and private insurers and providers should consider evidence-based cancer prevention and early detection services to be essential benefits and should provide coverage for them. These services at a minimum should include interventions recommended in the 2000 U.S. Public Health Service’s clinical practice guideline on treating tobacco use and dependence, screening for breast cancer among women age 50 and older, screening for cervical cancer among all sexually active women with an intact cervix, and screening for colorectal cancer among adults age 50 and older.
Public and private health insurers and providers who want to improve the health of their beneficiaries should include in their benefit packages coverage for evidence-based interventions for cancer prevention and early detection. Nicotine replacement therapy, treatment with certain antidepressants (e.g., Bupropion SR), and counseling, for example, are effective in helping individuals quit smoking. Very few insurers or health maintenance organizations cover the cost of pharmaceutical treatment for smoking cessation, and health education and preventive counseling are usually not defined benefits.
For insurers that offer coverage for preventive services, the reduction or elimination of cost sharing (e.g., coinsurance and copayments) can address a financial deterrent to seeking services and can improve the rate of service use (Solanki and Schauffler, 1999; Solanki et al., 2000). Employer benefits managers informed of the effectiveness of cancer prevention services might be motivated to obtain more comprehensive coverage for their employees.
Just as preventive services of proven effectiveness should be covered under insurance plans, services for which evidence of benefit is lacking should be excluded from coverage. Population-based or routine screening of smokers for lung cancer using spiral or helical computed tomography (CT) scans, for example, does not presently meet standards of evidence to support their coverage under health insurance plans.
Employers can provide coverage for preventive services as part of their insurance benefit packages, give discounts to employees who choose plans
with more extensive prevention services, and can create financial incentives for health plans to meet performance goals. Employers can also support wellness and physical fitness programs either through on-site facilities or through employee discounts to local gymnasiums or fitness programs.
Recommendation 5: The U.S. Congress should increase support for programs that provide primary care to uninsured and low-income people (e.g., Community and Migrant Health Centers and family planning programs of Title X of the Public Health Service Act). These programs increase the use of cancer prevention and early detection services among medically underserved populations.
A pervasive problem in the United States is poor access to health care because of a lack of health insurance. People with health insurance are more likely to have a primary care provider and to have received appropriate preventive care such as recent cancer screening tests. In 2001, an estimated 15 percent of the U.S. population (41.2 million individuals) was uninsured during the entire year (U.S. Census Bureau, 2002). Many others are underinsured, with poor coverage for interventions that have been proven to be effective, such as smoking cessation counseling and products.
Individuals who are uninsured (or underinsured) rely on a patchwork of public and private programs for primary care (IOM, 2000d). Community and Migrant Health Centers and Title X family planning clinics are vital sources of primary health care and are important providers of cancer prevention and early detection services. Full support for these programs enhances the nation’s health care safety net and at the same time extends the availability of cancer prevention and early detection services to vulnerable populations. Even with increased program support, however, many people would likely remain underserved, given the fragmented and limited nature of the nation’s health care safety net.
Recommendation 6: Support for the Centers for Disease Control and Prevention’s National Breast and Cervical Cancer Early Detection Program should be increased so that the program can reach all uninsured women using innovative delivery strategies. Support is also needed for a similar program at the CDC to provide screening for colorectal cancer for uninsured and low-income men and women.
Underfunding of CDC’s National Breast and Cervical Cancer Early Detection Program (NBCCEDP) contributes to lost opportunities for prevention. NBCCEDP has succeeded in improving screening rates among medically underserved populations, but the program reaches only 15 percent of eligible women because of limited financial support. This is especially unfortunate insofar as racial, ethnic, and socioeconomic disparities in cancer mortality can often be traced to under-use of screening services.
Because screening for colorectal cancer is also a proven strategy for reducing cancer mortality in people over 50 years of age, a similar program is needed to provide colorectal cancer screening to people who are uninsured and underinsured. The majority of individuals eligible for colorectal screening have not been screened, and screening rates are particularly low among minority and low-income populations.
Recommendation 7: The U.S. Department of Health and Human Services should complete a comprehensive review to assess whether evidence-based prevention services are being offered and successfully delivered in federal health programs.
The federal government administers or funds Medicare; Medicaid; the Health Resources and Services Administration’s Community and Migrant Health Centers; Title X family planning clinics; the U.S. Department of Agriculture’s programs such as the Special Supplemental Nutrition Program for Women, Infants, and Children; the Indian Health Service; U.S. Department of Defense health programs; and Federal Employees Health Benefits Program. These programs do not always reflect best practices in cancer prevention and early detection.
The Medicare program, for example, does not cover any costs for smoking cessation treatment, and two-thirds of state Medicaid programs cover such treatments (Schauffler et al., 2001a). The lack of coverage for effective prevention services in public programs introduces a significant barrier to those most burdened by cancer: the uninsured population and members of racial and ethnic minority groups who often depend on federal programs for care.
Evidence-based prevention services should be available in these and other public programs. Therefore, a comprehensive review of the benefits being offered and the effectiveness of delivery systems is needed to identify opportunities to improve access to cancer prevention and early detection services in federal programs.
Recommendation 8: Programs are needed for health care providers to improve their education and training, monitor their adherence to evidence-based guidelines, and enhance their practice environments to support their provision of cancer prevention and early detection services.
Primary care providers in health care settings are effective agents of behavioral change. When counseled about smoking in clinical settings, 5 to 10 percent of individuals are able to quit. Evidence suggests, however, that physicians and other practitioners are not providing effective clinical interventions such as counseling and screening tests as often as would be beneficial. Fewer than half of adults who smoke cigarettes, for example, report that at their last visit the physician inquired whether they smoked.
Shortcomings in providers’ delivery of clinical preventive services can, in part, be traced to a lack of education and training. Strategies for improving education and training include:
Professional education and training programs should adequately cover cancer prevention and early detection in their curricula.
Training institutions and professional organizations should provide continuing education in cancer prevention and early detection. Continuing medical education programs can be made more accessible by applying new learning technologies (e.g., distance learning and online continuing medical education).
Professional organizations representing primary care providers should promote their members’ adherence to evidence-based cancer prevention and early detection guidelines.
Systems of health care depend on supportive management structures; efficient patient-flow procedures; and information systems that support reminder systems, documentation of services, timely follow-up and referrals, and coordinated communication with providers and institutions across the community. Evidence consistently shows that such support systems improve physician and patient compliance with recommended preventive practices.
Health systems should support the infrastructure needed to identify patients in need of intervention (e.g., smokers or those who are due for screening), remind providers to intervene, and track progress toward clinical goals.
Efforts to improve the quality of health care delivery have increasingly relied on monitoring the performance of health care providers and systems of care. There are many opportunities to monitor performance and assist providers in improving their practices:
CMS could examine provider performance regarding adherence to recommended cancer prevention and early detection recommendations. CMS has specified in the most recent scope of work for Quality Improvement Organizations that the quality of breast cancer services is a priority area. Assessments of provider adherence to mammography guidelines could be undertaken.
State health departments could use data from cancer registries to examine regions and population subgroups characterized by high rates of late-stage diagnoses of breast, cervical, and colorectal cancer, for which screening programs are available, to identify where to target outreach efforts.
The National Committee for Quality Assurance could expand efforts to monitor preventive practices of managed care plans through its Health Plan Employer Data and Information Set system.
Employers and other group benefit managers could define performance targets for health education and preventive counseling to hold health plans accountable for the provision of these services (Schauffler et al., 1999; Schauffler and Rodriguez, 1996).
The Joint Commission on the Accreditation of Healthcare Organizations could evaluate the availability of services to promote risk behavior change as part of its accreditation process.
The aging of the nation’s population will sharply increase the demand for certain cancer prevention services such as colorectal screening and mammography, and impending shortages of trained personnel have been predicted. If such shortages are anticipated, policies to address them will need to be identified.
The Health Resources and Services Administration should assess the adequacy of the future supply of providers of cancer prevention and early detection services.
There is convincing evidence that nonphysician providers are just as effective as physician providers in delivering certain smoking cessation and screening services, but research is needed on how to integrate provision of prevention services by such providers into routine primary care.
The Agency for Healthcare Research and Quality and other research sponsors should support demonstration programs to evaluate innovative models of prevention service delivery.
Recommendation 9: The U.S. Congress should provide sufficient support to the U.S. Department of Health and Human Services for the U.S. Preventive Services Task Force and the U.S. Task Force on Community Preventive Services to conduct timely assessments of the benefits, harms, and costs associated with screening tests and other preventive interventions. Summaries of recommendations should be made widely available to the public, health care providers, and state and local public health officials and policy makers.
Evidence-based guidelines for clinical and community practice provide maps for action. Two task forces provide rigorous assessments of the effectiveness of preventive services.
The U.S. Preventive Services Task Force, overseen by the Agency for Healthcare Research and Quality, has provided comprehensive assessments of clinical prevention services. Until recently, it has been convened only
periodically. In 2001 the task force published selected updates of recommendations made in 1996 (U.S. Preventive Services Task Force, 2001a,b, 2002). Assessments of prevention services are needed on a continual basis to ensure that public health recommendations incorporate the latest scientific evidence.
The U.S. Community Services Task Force, overseen by CDC, is relatively new and has the responsibility to identify interventions that work for communities. As state efforts to implement comprehensive cancer control plans gain momentum, guidance on the effectiveness of public health interventions will be critically needed.
The Board recommends that support for both task forces be sufficient for systematic syntheses and meta-analyses of data from the literature and to keep abreast of developments in both clinical and community disease prevention and health promotion. Greater investments in dissemination activities are also needed to reach health providers and the general public, both about areas of consensus among public health scientists regarding interventions that work, and about the areas of controversy that remain.
There are examples of screening and other prevention interventions that were quickly adopted before adequate research had been completed to fully understand their potential benefits and harms. Screening for prostate cancer by prostate-specific antigen testing, for example, for which there is comparatively little evidence of effectiveness, is more commonly used than colorectal cancer screening, for which there is strong evidence of effectiveness. More recently, low-dose computed tomography scanning has been promoted as a screening test for lung cancer among high-risk individuals, with the scientific community divided on the merits of its effectiveness. It will be years before the results of clinical trials are available to answer questions about the test’s effectiveness. These two task forces can provide clear information on the potential benefits, harms, and costs of new technologies so that consumers and health care providers can make informed judgments.
Recommendation 10: Public and private organizations (e.g., the National Cancer Institute, the American Cancer Society) should take steps to improve the public’s understanding of cancer prevention and early detection with a focus on promoting healthy lifestyles and informed decision making about health behaviors and cancer screening.
Raising public awareness of the benefits of cancer prevention and early detection is central to reducing the cancer burden. One barrier to effective communication is the contradictory and sometimes questionable research reported by the media.
The public’s thirst for quick medical “miracles” and simple impatience also pose significant barriers to progress in cancer prevention and early
detection. It can take many years to reap the benefits of behavioral change like smoking cessation. Significant reductions in breast cancer mortality rates as a result of screening programs have only recently been observed in the general population. The fascination of the American public with advanced technology and “getting tested,” the commercial and marketing interests in servicing this demand, and the sense of urgency to take action in combating cancer set the stage for the premature adoption of interventions that are potentially ineffective or harmful.
Increasingly, cancer screening guidelines incorporate the tenets of informed decision making. Rather than issuing prescriptive recommendations regarding prostate-specific antigen testing, for example, most organizations are suggesting that individuals discuss the relative benefits and harms of screening, weigh these factors according to their individual values and preferences, and decide whether or not to proceed with screening. Although this shared decision-making approach tends to be embraced by the well-educated health consumer, little is known regarding its acceptance among the general public and how best to incorporate it into the delivery of preventive services.
Improved understanding of cancer prevention by the general public is also critical to support for research in this area. Although the public is generally supportive of clinical medical innovation, it has less of an appreciation of the potential of public health interventions.
Recommendation 11: Public and private initiatives to reduce disparities in the cancer burden (e.g., initiatives of the National Cancer Institute and the American Cancer Society) should be supported.
There are glaring disparities in rates of morbidity and mortality from cancer among socioeconomic groups, insured and uninsured populations, and certain racial and ethnic groups (IOM, 1999b). The differences among these groups present both a challenge to understand the reasons and an opportunity to reduce the burden of cancer (U.S. Department of Health and Human Services and Office of Disease Prevention and Health Promotion, 2000). Lack of health insurance coverage is a key predictor of lower rates of use of cancer screening tests. Personal barriers can include cultural differences, language barriers, not knowing how or when to seek care, or concerns about confidentiality or discrimination (U.S. Department of Health and Human Services and Office of Disease Prevention and Health Promotion, 2000). In a nation of increasing diversity, interventions to improve cancer prevention and early detection must accommodate different languages, cultural values, and beliefs.
The elimination of racial and ethnic disparities in health is an over-arching goal of Healthy People 2010 (U.S. Department of Health and Human Services and Office of Disease Prevention and Health Promotion, 2000), and cancer screening and management is one of six focus areas of an
ongoing initiative involving agencies of the U.S. Department of Health and Human Services (http://raceandhealth.hhs.gov/sidebars/sbinitOver.htm). The National Institutes of Health (NIH) has drafted a trans-NIH, 5-year Strategic Research Plan to Reduce and Ultimately Eliminate Health Disparities (www.nih.gov/about/hd/strategicplan.pdf), and in December 2000 the National Cancer Institute (NCI) established the Center to Reduce Cancer Health Disparities (http://crchd.nci.nih.gov) to implement the NCI Strategic Plan to Reduce Health Disparities. The Board fully supports this NCI initiative and encourages NCI to collaborate with other private and public efforts to achieve success. Also needed are effective methods to evaluate and track the success of this and other initiatives.
Recommendation 12: Public and private sponsors of research including the National Institutes of Health, the Agency for Healthcare Research and Quality, the Centers for Medicare and Medicaid Services, the Centers for Disease Control and Prevention, the U.S. Department of Defense, and the American Cancer Society should expand their support of applied behavioral research and how best to disseminate evidence-based prevention interventions. Effective strategies are especially needed to encourage healthy behaviors among children and their families, medically underserved populations, and the public at large through multicomponent interventions.
The United States is at a crossroads in cancer prevention research. Basic science and epidemiology are advancing knowledge in a number of areas, from the relationship between cancer and modifiable behavioral risk factors all the way down to the molecular pathways that mediate the actions of those risk factors. At the same time applied research is illustrating how the already vast amount of available evidence can be better used to more rapidly reduce cancer rates. To effectively reduce the cancer burden in the United States, however, there needs to be greater emphasis on action-oriented research (Colditz, 1997, 2001; Wegman, 1992). Knowledge about health problems and their causes does not automatically guarantee that appropriate actions are taken. Only when etiological knowledge is linked to evidence on the sustained effectiveness of behavioral change strategies, and in turn to public awareness and policy support, can the potential to reduce the burden of cancer be realized.