Regular use of baby aspirin prior to a diagnosis of colorectal cancer may reduce the risk of death from the disease, Cedars-Sinai Cancer researchers said Monday.
Taking the drug at least 15 times per month pre-diagnosis has been linked to limiting the spread of cancerous tumors, according to the study published in the Journal of National Cancer Institute.
Starting aspirin after a colorectal cancer diagnosis was not associated with as strong a benefit as pre-diagnosis use, the researchers found. And the use of non-aspirin, nonsteroidal anti-inflammatory drugs such as ibuprofen, acetaminophen and naproxen, failed to confer the same benefits.
“More evidence is needed, but this association between baby aspirin and lower death rates is highly significant,” said epidemiologist and lead study author Jane C. Figueiredo. “These findings may provide an inexpensive lifestyle option to people seeking to prevent colorectal cancer, or to improve their prognoses if they are diagnosed.”
Colorectal cancer starts in the colon or the rectum and is the third-leading cause of cancer death for men and women in the U.S., causing about 53,000 deaths last year. The American Cancer Society estimates that about 104,600 cases of colon cancer and 43,300 cases of rectal cancer were diagnosed in the U.S. in 2020. Treatment usually involves surgery to remove the cancer, and possibly radiation therapy and chemotherapy.
Researchers said low-dose aspirin use irreversibly prevents blood cells called platelets from activating and producing the enzyme thromboxane A2, which allows them to clump together. Tumor cells can attach to these clumps of platelets and spread throughout the body.
“Aspirin inhibits platelet activation, which also could inhibit metastases,” explained Figueiredo, the director of Community and Population Health Research and an associate professor of Medicine at the Samuel Oschin Cancer Institute at Cedars-Sinai.
The observational study conducted by Figueiredo and colleagues included data from more than 2,500 men and women enrolled in the American Cancer Society Cancer Prevention Study-II nutrition cohort. All shared information about their aspirin and non-aspirin NSAID use and all eventually were diagnosed with colorectal cancer. Researchers tracked participants’ outcomes from their time of enrollment in 1992 or 1993 through December 2016.
Figueiredo said that ongoing clinical trials are examining the impact of aspirin use, before and after diagnosis, on colorectal cancer mortality. When completed, they will provide additional guidance for physicians recommending treatments for their patients.
“We have to wait until those results come out,” Figueiredo said. “There are potential harms associated with aspirin use… There really needs to be a conversation between clinicians and patients about both the risks and benefits. These studies and our results really add to that conversation.”