Wednesday May 28 5:52 PM EDT

--In the early 1970s, President Nixon declared war on cancer, but 25 years later, that war is far from over. The good news is that fewer people are dying from cancers of the cervix, uterus, colon, rectum and stomach, and in particular, fewer children are dying of cancer. Yet, the mortality rate from breast and prostate cancer, l ymphomas, brain tumors and melanoma are stable or slightly increasing, despite improvements in detection and treatment.

A new plan of attack may be needed in the war on cancer, including a greater emphasis on preventing the disease from occurring in the first place, according to Dr. John Bailar and Heather L. Gornik of the Department of Health Studies at the University of Chicago in Illinois.

"The effect of new treatments for cancer on mortality has been largely disappointing," they reported in this week's issue of The New England Journal of Medicine. 1'The most promising approach to the control of cancer is a national commitment to prevention, with a concomitant rebalancing of the focus and funding of research."

The cancer mortality rate climbed by 6% from the 1 970s to 1 990s, despite the passage of the National Cancer Act in 1971 to expand cancer research programs. The mortality rate finally plateaued in 1991 at 203 deaths per 100,000 people, and since then has declined by about 1% per year -- mostly due to declining cancer deaths in black males and people younger than 55.

"Some declines are clearly a result of reduced incidence or earlier detection (cancer of the cervix, other cancers of the uterus, and cancers of the colon, rectum and stomach)," Bailar and Gornik wrote. "Similarly, recent changes in mortality from lung cancer are certainly due to changes in smoking patterns over the past f ew decades." The lung cancer death rate has declined steadily in those under 55, and is beginning to decline in men over 55, but is rising steadily in women over 55-- increasing fourfold since 1970.

For children, the cancer rate has dropped significantly since 1970, about 50% for all types of cancer. That drop is due to better understanding of cancer and improved treatment -- but because so few children get cancer, the decline has a minimal impact on the cancer death rate overall.

"Hopes for a substantial reduction in mortality by the year 2000 were clearly misplaced," the researchers wrote. While research into cancer treatment should continue, there also should be a greater emphasis on cancer prevention.

Prevention includes everything from finding new ways to help people to quit smoking, to understanding how the diet and genes predispose some individuals to cancer, as well as reducing exposure to carcinogens and improving cancer surveillance.

"In our view, prudence requires a skeptical view of the tacit assumption that marvelous new treatments for cancer are just waiting to be discovered," Bailar and Gornik concluded. "We, like others, earnestly hope that such discoveries can and will be made, but it is now evident that the worldwide cancer research effort should undergo a substantial shift toward efforts to improve prevention."

SOURCE: The New England Journal of Medicine (1997;336:1569-1574)