The death of the Women's Health Trial on Jan. 7 marks the birth of the need to question the National Cancer Institute's commitment to halting the breast cancer epidemic among American women.
Acknowledging the excellent progress scientists have made in detecting and treating breast cancer, we must still question the validity of funding research primarily in these areas -- and not in prevention.
This practice conveys a message to American women that NCI is committed to breast cancer control rather than prevention. While studies investigating the dietary fat-breast cancer link proceed in Canada, NCI scientists remain deadlocked in deciding on standards for prevention research.
The Women's Health Trial (WHT) was designed by scientists committed to preventing breast cancer through investigating the long-term effects of low-fat diet on breast cancer. The link between dietary fat and breast cancer was considered strong enough, based on both animal and human studies, for the NCI to fund a feasibility phase for the WHT four years ago, which was conducted with 300 women at three sites in Seattle, Houston and Cincinnati.
These women were 45 to 69 and had 1.4 times the national average risk of developing breast cancer because of family and medical history. The intervention group of women in this trial were instructed in lowering the fat in their diets from the American average of 40 percent of total calories to 20 percent. The control group continued eating the standard American diet.
The results of the Women's Health Feasibility Trial conducted during 1985 were presented to the Policy Advisory Committee (PAC) of the Nationa Cancer Institute's Division of Cancer Prevention and Control in January 1986.
Along with successful dietary change, the WHT also produced significant reductions in total serum cholesterol. It is important to note that these blood chemistry changes were made utilizing readily available foods and that there were no adverse health effects as a result of the diet. The motivation and satisfaction levels of participants were strong, as evidenced by almost full attendance by women at six-month and 12-month clinic visits and intervention sessions.
This one-year feasibility trial could not, however, prove or disprove the underlying hypothesis of the study that reducing dietary fat would reduce the incidence of breast cancer. Principal investigators of the WHT, headed by Dr. Maureen Henderson of the Fred Hutchinson Cancer Research Center in Seattle, asserted that this could be done with a full-scale trial involving 32,000 women over a 10-year period for a cost of $100 million. Dr. Henderson justified this high price tag with the rationale that if the WHT ultimately found that breast cancer could be reduced by only 10 percent through low-fat diets, we would still save $500 million each year in treatment costs.
The Board of Scientific Counselors who did a final evaluation of the Women's Health Trial decided that the price tag was too high and "killed" the trial. The strong evidence for the relationship between dietary fat intake and breast cancer, which was considered "good science" when the trial was first approved, became poor science when large amounts of money were required to thoroughly investigate this hypothesis. Was it only the high price tag that caused the board to change its mind about "good science" and the worthwhile nature of this study?
Skeptical scientists claimed that there was no convincing biochemical proof that women had eaten the low-fat diets they claimed to eat and that there was no way to scientifically monitor food intake. Trial researchers claimed that significant differences in blood cholesterol levels found between the intervention and control groups as well as weight loss found in the intervention women were clear indicators that the women had been honest in recording their food intake.
Since this study was conducted in a "real life" setting rather than a laboratory one, participants were instructed in preparing low-fat diets for themselves and some trust was placed in their skill at doing this. An alternative would have been to conduct the study in a controlled environment like a hospital, where participants would come and be given all their meals. Unfortunately, this alternative does not correspond to the daily lives of most women. In other words, the methodology employed by Dr. Henderson and her colleagues was appropriate for testing the diet-breast cancer hypothesis. Their experiment was both justified and well-designed.
By discontinuing funding for the full-scale Women's Health Trial, the federal government is shirking its responsibility to American women and breaking a promise to support scientific investigation that seeks to prevent breast cancer. American women need to ask themselves why the National Cancer Institute is so reluctant to fund prevention studies and so willing to spend millions on detection and treatment studies, which are not permanently "curing" breast cancer. Why not work on preventing this disease before it occurs?
We need to ask ourselves why our government has funded large-scale studies on risk factors in cardiovascular disease since the 1960s, like the Western Collaborative Group Study, the Framingham Heart Study and the Multiple Risk Factor Intervention Trial, and so few prevention studies in breast cancer. Why are prevention-oriented cardiovascular studies good science while preventive breast cancer studies are not?
Commitment to prevention research in breast cancer will begin only after American women begin demanding answers to these questions. Until then, studies like the Women's Health Trial will continue to be quietly and systematically "killed."
Renee Royak-Schaler, PhD, is assistant professor of health sciences at Towson State University and resides in Silver Spring.