Study Finds ‘Alarming’ Increase in Cancer Rates : Health: In white men born 1948 to 1957, the incidence unrelated to smoking is triple that of their grandfathers. But some experts say the data may be distorted.

The sharp decline in deaths from cardiovascular disease in the United States during the last two decades has been accompanied by an unexpected increase in the overall incidence of cancer, and in cancer deaths among people over 55, researchers say.

White men born during the baby boom of 1948 to 1957 have nonsmoking-related cancer rates three times as high as those of their grandfathers, but the rate of cardiovascular disease has fallen by 43%, a government research team reports today in the Journal of the American Medical Assn.

White women in the same age group have 30% more cancer not related to smoking than did their grandmothers, but 500% more cancer caused by smoking. “This increase is really alarming,” said epidemiologist Devra Lee Davis of the U.S. Department of Health and Human Services, the primary author of the new report.

But the study also has some good news. The incidence of smoking-related cancer among men is now only about 10% higher than it was among their grandfathers, down dramatically from its peak in the first quarter of this century. “That’s a major public health victory,” said Edward Sondik, deputy director of the National Cancer Institute’s Division of Cancer Prevention and Control.

The study also found that cancer mortality among people under the age of 55 decreased by 17% between 1973 and 1987, but increased by 12% among older people. During the same period, the death rate from all causes dropped by 5%.

Other researchers expressed the need for caution in interpreting the increased incidence of cancer, as well as the cancer deaths among older people.

“In the United States, everyone eventually dies of something,” said Dr. Cary Presant, a professor of medicine at USC and chairman of the California Division of the American Cancer Society. When people do not die of heart disease, they live longer and have a higher risk of cancer. As a result of continuing improvements in controlling heart disease, he said, “by the year 2000, the leading cause of death will no longer be cardiovascular disease, but cancer.”

Davis and her colleagues do not know the cause of the increases in the cancer rate but suspect that they result from growing exposure to both known and undiscovered carcinogens in the environment. One strong clue, Davis said, is that farm families show an even higher death rate from the forms of cancer that have shown the greatest increase in the general population.

Such families have high exposures to a variety of agents, including pesticides, herbicides, engine exhausts, chemical solvents, animal viruses and sunlight, that could be the cause of the cancer rate increases, Davis said. The National Cancer Institute is initiating a study of more than 100,000 farm families to try to define the role of such exposures in producing cancer.

Other explanations might include increased exposure to hazardous materials in the workplace and changing patterns of alcohol use, Davis said. Prohibition and wartime restrictions limited the alcohol consumption of men born at the turn of the century, she noted.

“This study shows that we need a national commitment to public health research on the causes of these diseases that are increasing so that we can prevent them,” Davis said.

The new study is based on data collected in the first 15 years of the cancer institute’s Surveillance, Epidemiology and End Results program, an ongoing project in which cancer rates are determined in a representative 10% of the U.S. population.

The researchers focused solely on whites, Davis said, because “blacks and other minorities do not have equal access to health care.” Cancer and other diseases currently are less likely to be diagnosed at an early stage in blacks than in whites, she noted, and were much less likely to be diagnosed in the past. “We didn’t think it worthwhile to analyze the data (on blacks) because we might see an increase that wasn’t real.”

Critics cautioned that the observed increases in cancer might overstate the case somewhat. Sondik noted, for example, that cancer was stigmatized in many areas at the turn of the century and that many cases were given a more palatable--if inaccurate--diagnosis. Techniques for identifying many types of tumors, particularly those of the brain and prostate, have improved significantly, he added, leading to sharp increases in their reported incidences.

“Nonetheless, this tells us something very important about the public health impact of cancer,” he said.