Achieving better cancer care and control within these underserved and high-risk populations is an extremely important goal. Even with additional emphasis, cancer will likely continue to be one of the leading causes of death in the early years of this century. Furthermore, the aging population will dramatically change the patterns of cancer in this century because cancer risks increase with age.
Thus, the need for research on special populations is greater than ever before because these populations are the most vulnerable to negative consequences from the rapidly changing health care system. As several speakers emphasized, “One size does not fit all.” We must be creative in our approach to addressing cancer in various populations. As Dr. Lovell Jones emphasized, if we do what we have always done, then we will get what we always got. For these reasons, many panelists and speakers urged participants to conduct additional research on special populations to address disparities in incidence rates, mortality rates, and access to care in these populations and to put a greater emphasis on environmental disease surveillance including more complete cancer registries across all populations.
Presentations throughout the two days highlighted the fact that many lifestyle and environmental carcinogens have been identified by investigating cancer in populations and that this knowledge has led to new approaches for reducing cancer risk. Yet there is still much to learn about the causes of cancer, particularly why one person with the same cancer-causing exposure (such as smoking or diet) develops cancer, whereas another does not. Individuals’ genetic makeup can affect their risk for developing cancer in ways more subtle than those seen in familial cancer syndromes. Variations in genetic susceptibilities related to how individuals control and respond to endogenous hormone levels, diet, exposure to carcinogens, sun, and infectious agents are likely to influence a given individual’s chance of developing cancer.
According to many speakers, the estimates of cancer incidence support the claim that in an ideal world, more than 50 percent of cancers could be prevented if what is already known about the etiology and early course of cancer were acted on and fully adopted. These speakers also noted that tobacco use accounts for 30 to 40 percent of preventable cancer mortality; diet for another 20 to 40 percent; and alcohol, occupational exposure, and pollution for the remaining 5 to 17 percent. We have seen decreases in some cancer rates in the past 50 years due to positive changes in society. For example, stomach cancer and cervical cancer declined from 1950 to 1993 due to changes in food preparation and storage and improvements in medical screening and early treatment, respectively. In the 1990s, there was a modest (1 to 3 percent) overall age-adjusted decrease in cancer death rates. This decrease can be attributed to changes in behavior and environment, for example, successful reductions in smoking and better early