For instance, other research has found that women with breast cancer who regularly take aspirin, which is an anti-inflammatory, may have a decreased risk of recurrence.
"I think this study is interesting, but very far from being conclusive," said Chung. It's not known, she said, whether there is a true association or whether it may be due to chance or another factor.
"There is more work to be done before you can say whether this relationship is meaningful and will hold up," agreed Dr. Len Lichtenfeld, deputy chief medical officer for the American Cancer Society.
As in other retrospective studies, he said, more research is needed to verify the potential link.
"There are many other factors that come into play that could explain what happened," Lichtenfeld said. "What if the women who take the beta blockers are more attuned to their health and they may be taking better care of themselves?"
Like Chung, he agreed the proposed association is not far-fetched, just that more study is needed. Previous research, Lichtenfeld said, has found a reduced rate of skin cancer among men who take another type of blood pressure-lowering drug.
Powe said he plans to do another study to validate the results.
To learn more about inflammation and cancer, visit the U.S. National Cancer Institute.
SOURCES: Des Powe, Ph.D., senior healthcare research scientist, Queen's Medical Centre, Nottingham University Hospital NHS Trust, Nottingham, U.K.; Len Lichtenfeld, M.D., Ph.D., deputy chief medical officer, American Cancer Society, Atlanta; Cathie Chung, M.D., Ph.D., medical oncologist and assistant professor, oncology, City of Hope National Medical Center, Duarte, Calif.; March 26, 2010, presentation, European Breast Cancer Conference, Barcelona
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