In overweight and obese women who used aspirin or other nonsteroidal anti-inflammatory drugs regularly, the recurrence of hormone-related breast cancer was cut by half, found in a data published in Cancer Research, a journal of the American Association for Cancer Research.
"Our studies suggest that limiting inflammatory signaling may be an effective, less toxic approach to altering the cancer-promoting effects of obesity and improving patient response to hormone therapy," said Linda A. deGraffenried, PhD, associate professor of nutritional sciences at The University of Texas in Austin.
The study found that women whose body mass index (BMI) was greater than 30 and had estrogen receptor alpha (ERα)-positive breast cancer had a 52 percent lower rate of recurrence and a 28-month delay in time to recurrence if they were taking aspirin or other NSAIDs.
"These results suggest that NSAIDs may improve response to hormone therapy, thereby allowing more women to remain on hormone therapy rather than needing to change to chemotherapy and deal with the associated side effects and complications," said deGraffenried. "However, these results are preliminary and patients should never undertake any treatment without consulting with their physician."
Using blood from obese patients, deGraffenried and colleagues conducted experiments in the laboratory to recreate a tumor environment containing cancer cells, fat cells, and the immune cells that promote inflammation. They found that the factors associated with obesity initiate a network of signaling within the tumor environment to promote growth and resistance to therapy.
"These studies show that the greatest benefit from aspirin [and other NSAIDs] will be in those with a disease driven by inflammation, and not just obesity," explained DeGraffenried.
Researchers used data from 440 women diagnosed with invasive, ERα-positive breast cancer and treated at The University of Texas Health Science Center and the START Center for Cancer Care clinic, both in San Antonio, Texas, between 1987 and 2011.
Of the women studied, 58.5 percent were obese and 25.8 percent were overweight. About 81 percent took aspirin, and the rest took another NSAID. About 42 percent and 25 percent took statins and omega-3 fatty acid, respectively.
There was an indication of protection from aspirin and other NSAIDs even after controlling for statins and omega-3 fatty acid use, which also have anti-inflammatory effects.