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Setting Goals for Cancer Mortality: Earlier Initiatives Offer Lessons for the Future

Katherine Arnold

Earlier this year, National Cancer Institute director Andrew C. von Eschenbach, M.D., issued a challenge goal to the cancer community to completely eliminate death and suffering from cancer by the year 2015. Although the director has yet to release specifics, two similar plans, one from NCI and one from the American Cancer Society, provide some insight into the effort and coordination that will be central to achieving a major effect on the nation’s cancer mortality rate.

NCI’s Goal for 2000

In 1986, the newly formed NCI Division of Cancer Prevention and Control published a monograph that defined an ambitious plan for an ambitious goal—a 25% to 50% reduction in the cancer mortality rate from the 1980 level by the year 2000. That number was calculated based on a series of estimates about how much particular risk factors, lifestyle factors, and cancer treatment factors contributed to the overall burden of cancer (see table, p. 1501). Working groups in four areas—cancer prevention, screening and detection, treatment, and surveillance—had been asked to come up with estimates of how much of a reduction in mortality could be achieved by 2000 if specific and ambitious programs were put in place.

The monograph also defined a series of objectives to be achieved by 2000 in cancer prevention, screening, and treatment. It called for reductions in the percentage of adults and teens who smoke, reductions in the average consumption of fat and an increase in the average consumption of fiber, an increase in the use of mammography and Pap smears, and an increase in the adoption of state-of-the-art treatments.

"This report provides the background for the NCI projection that a significant fraction of cancer mortality can be eliminated during the next 15 years with widespread aggressive application of existing knowledge and expected advances in knowledge," the report’s editors, Peter Greenwald, M.D., Dr.P.H. (now the director of the NCI’s Division of Cancer Prevention), and Edward J. Sondik, Ph.D. (now the director of the National Center for Health Statistics), wrote in the monograph. "Achievement of this potential depends on the effective coordination of cancer control activities at the federal, state, and local levels and the active participation of volunteer and professional organizations."

But it was a lack of coordination that ultimately led to the objectives falling by the wayside and many of the report’s goals not being achieved. "There wasn’t a full buy-in, especially as directors changed, and then it was just sort of dropped," Greenwald said in an interview this August. "We ended up with goals and recommendations without a full buy-in or real resource allocation for all the different groups that needed to play a role."

John C. Bailar III, M.D., Ph.D., now professor emeritus in the Department of Health Studies at the University of Chicago, was openly critical of the NCI goal. "It is clear that the [goal of a 50% reduction in cancer mortality] will not be attained unless the present upward trend is reversed very soon and there is a precipitous and unprecedented decline," Bailar and colleague Elaine M. Smith, Ph.D., wrote in an article in the New England Journal of Medicine in 1986. "We do not believe that hopes for such a change are realistic."

In retrospect, Bailar said that the outlined plan for the mortality reduction did not have the means to make it succeed. "The fundamental flaw that I saw in that plan was that it was counting on everyone else to do what NCI said they should do, without evidence that that would happen and without proof that it would have the effects that were projected," Bailar said.

Greenwald added that weak national policies on tobacco control and the wealth and influence of the tobacco industry slowed the progress of reducing smoking rates. In addition, obesity rates have reached epidemic levels, and adoption of state-of-the-art treatments and detection technology was uneven, he said.

Cancer mortality rates did indeed decrease from 1994 through 1998, but the final calculation of the decrease between 1980 and 2000 fell far short of the 25% to 50% goal: The 1980 cancer mortality rate was 207.0 per 100,000, and the 2000 rate was 199.6 per 100,000—a decrease of 3.6%. (The mortality rate peaked in 1991 at 215.1 per 100,000, for a decrease of 7.2% between 1991 and 2000.)

ACS Challenge Goal

The NCI had used estimates for mortality reductions in specific areas to calculate its overall goal. A decade later, the American Cancer Society took a somewhat opposite approach. In 1996, when cancer mortality had begun its downward trend, the group took the opportunity to further inspire the cancer community by announcing a challenge goal for a 50% reduction in the cancer mortality rate by 2015. It was not until a few years later that an ACS committee took a hard look at the feasibility of that goal.

"The approach we wanted to take is to say, what do we really know about the determinants of cancer incidence and mortality and what do we know about the changes or rate of change in those risk factors," said Tim Byers, M.D., professor in the Department of Preventive Medicine and Biometrics at the University of Colorado School of Medicine, Denver. "Then, if we could couple that information with some assumptions about the lag time it takes between the change in a behavior and the change in cancer, then we should be able to project into the future what the approximate direction and magnitude of future changes would be."

Byers and colleagues from the ACS Reduction in Cancer Incidence and Mortality Committee used this approach to calculate that, if the trends in cancer risk factors present at the time of the analysis (1999) held true, then a 13% decline in cancer incidence and a 21% decline in cancer mortality from 1990 levels could result. If efforts to reduce the prevalence of known cancer risk factors were substantially increased, then the cancer incidence rate could be reduced by 19% and the mortality rate by 29%.

"We concluded that ... it’s quite likely that we’ll get halfway [to the goal of a 50% reduction in cancer mortality] just by what we know, which means if we fill up the other half of the glass with new knowledge or new efforts or new programs, then maybe it’s not out of reach that this kind of goal could be achieved," Byers said. "Of course there are always the proverbial magic bullets in the pipeline of new drugs that could [come to fruition] between now and then. We won’t try to guess what the impact of those will be. That will have to be in the part of the goal that won’t be achieved without new breakthroughs."

Their model for their calculations was based on several assumptions regarding fruit and vegetable intake, alcohol intake, cancer screening, cancer therapy, use of antiestrogens, and, of course, tobacco use.

"Tobacco is the big gorilla in all of cancer control," Byers said. "Just a few percentage points’ shift in tobacco use makes a huge difference compared to, for instance, mammography. Mammography rates are already pretty high, and even though mammography is important for preventing breast cancer deaths, it still prevents a much smaller proportion of all cancers than does tobacco."

The ACS committee that did the 1999 analysis plans to revisit the issue sometime this year, Byers said. They will take into consideration changes in the trends of tobacco use that have occurred in the last 4 years, changes in screening rates, and the obesity epidemic that shows no signs of abating.

"In our earlier projections, we regarded obesity as a wash, in that we knew that obesity was increasing in the United States and that it had an impact on cancer mortality, but we had assumed that we would be able to turn around the obesity epidemic sufficiently by 2015 so that at that point in time it would be a wash," Byers said. "It’s clear that obesity is a very important nutritional factor."

Future Goals

Both the NCI objectives and the ACS challenge goal had their critics, many of whom challenged the reductions as unreasonable and uninspiring. Earlier this year the National Cancer Policy Board discussed such goals in its report, Fulfilling the Potential of Cancer Prevention and Early Detection. "Goals usually incorporate an element of hope that new research will lead to favorable outcomes," the board wrote. "Although setting lofty goals may be intended to provide extra motivation to individuals and institutions, goals that are unrealistic can have the opposite effect. ... Challenge goals that are set to motivate the application of current knowledge and the research for new knowledge must be accompanied by the attention and resources needed to move toward success."

von Eschenbach has acknowledged that his challenge goal for the cancer community is ambitious, but he said he is confident that it is realistic. "I think the important point is to focus not on 2015 as some magic moment," he said in a press conference earlier this year. "I think the important point is to focus on the opportunity that exists in 2003 to enable us to conquer the burden of cancer and eliminate the suffering and death that occurs as a result of it. ... The timeline is aggressive, and that’s why I call it a challenge."



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