Leslie Bernstein

Bernstein, professor of preventive medicine at the Keck School of Medicine at USC, pointed to the debate over the relationship between induced abortions and breast cancer risk to illustrate the impact that politics and advocacy exert on research. Though the weight of scientific evidence suggests there is no link between having an induced abortion and an increased risk of breast cancer, three states have enacted laws requiring women to be informed of such a purported link. Thirteen states in 2003 and 14 states in 2004 considered enacting statutes that would have required that women be made aware of a link.

"We do need, at times, to step aside from what we're doing and to stand behind our science, because we don't want science used to the detriment of women," Bernstein said.

She described a Congressionally-mandated study that was established in response to breast cancer advocates who perceived that rates of breast cancer were particularly high in the Long Island, NY, area.

"This study used Congress as a vehicle to initiate research," Bernstein said, "and we can ask the question, 'How much should elected representatives be involved in steering our research?'"

Advocates who had pushed for the study were disappointed when no link was found between environmental contaminants and an increased risk of breast cancer, asserted Bernstein. "To the advocates who wanted this study done, it was a failure-negative findings are considered a failure," she said. She later explained in a Q&A session that scientists may help avoid acrimony with advocates if they make a strong effort to interact with them so that the groups view each other with respect and understanding.

Bernstein also focused on the science of breast cancer itself, particularly the factors thought to affect a woman's risk. The field has made notable progress, while leading to more questions. For instance, studies conducted by Bernstein and others support the idea that exercise decreases risk. Yet this conclusion raises more questions than it answers. At what age should women exercise and to what extent? What type of exercise is most beneficial in decreasing risk? Do genes play a role-will some women benefit from exercise more than others? How can researchers motivate sedentary women to engage in exercise? Identifying the link between exercise and decreased breast cancer risk has yet to result in a feasible prescription for action.

The link between breast cancer and the age at which a woman gives birth to her first child has also produced more questions than answers. If an early pregnancy protects against breast cancer because of hormone production, it remains to be seen which hormones are involved and whether researchers can determine how to artificially provide the protection afforded by an early term pregnancy. It also remains unclear if a focus on the hormones of pregnancy will be more effective than a focus on other risk factors.

Bernstein noted that venturing into uncharted research territory produces not only many questions but also unexpected opportunities to improve breast cancer prevention and to save lives.

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