Psychosocial stress could play a role in the etiology of breast cancer aggressiveness according to study results presented at the Fourth AACR Conference on The Science of Cancer Health Disparities.

"We found that after diagnosis, black and Hispanic breast cancer patients reported higher levels of stress than whites, and that stress was associated with tumor aggressiveness," said Garth H. Rauscher, Ph.D., associate professor of epidemiology in the division of epidemiology and biostatistics at the School of Public Health, University of Illinois at Chicago.

Rauscher and colleagues studied patient-reported perceptions of fear, anxiety and isolation, together referred to as psychosocial stress, and associations with breast cancer aggressiveness. He cautioned that patients' stress levels were examined two to three months post-diagnosis.

The study included 989 breast cancer patients who were recently diagnosed; of those, 411 were non-Hispanic black, 397 were non-Hispanic white, and 181 were Hispanic. Results showed that psychosocial stress scores were higher for both black and Hispanic patients compared to white patients.

"Those who reported higher levels of stress tended to have more aggressive tumors. However, what we don't know is if we had asked them the same question a year or five years before diagnosis, would we have seen the same association between stress and breast cancer aggressiveness?

"It's not clear what's driving this association. It may be that the level of stress in these patients' lives influenced tumor aggressiveness. It may be that being diagnosed with a more aggressive tumor, with a more worrisome diagnosis and more stressful treatments, influenced reports of stress. It may be that both of these are playing a role in the association. We don't know the answer to that question," Rauscher said.