Share on PinterestLow-dose aspirin may slash colorectal cancer recurrence risk by 55%, according to a recent trial. Image credit: soleg/Getty Images
- A new clinical trial tested low-dose aspirin in patients with colon and rectal cancer, also referred to as colorectal cancer.
- The researchers wanted to see if taking aspirin daily could help prevent cancer from recurring in people who had a PIK3 genetic mutation.
- In 3 years’ time, aspirin reduced the risk of cancer recurrence in people with the PIK3 mutation by up to 55% compared to the placebo group.
The National Cancer Institute predicts that colorectal cancers will make up 8% of new cancer cases in 2025, and it is often recurring, so scientists are looking for ways to reduce the risk of it coming back.
Researchers with the Karolinska Institute in Sweden conducted a trial to test aspirin in people with colorectal cancer. They focused on people whose tumors impacted the PIK3 signaling pathway, which make up one-third of colorectal cancer cases.
Participants who took aspirin saw their recurrence risk more than cut in half. Considering how inexpensive and readily available aspirin is, the findings show it could become an important tool for reducing colorectal cancer recurrence in some people.
The study is published in The New England Journal of Medicine.
Can low-dose aspirin help prevent recurrence?
Colorectal cancer is a relatively common cancer and affects people of all genders. Some things that can increase one’s risk for developing this type of cancer include genetics, lifestyle factors — such as smoking and a diet high in red meat — and inflammatory bowel disease (IBD).
If colorectal cancer is detected early and is localized, the American Cancer Society reports that the 5-year survival rate is 91% for colon cancer and 90% for rectal cancer.
The authors noted that prior studies involving aspirin and colorectal cancer were inconsistent, so they wanted to conduct a double-blind trial to test how a daily low dose of aspirin worked in people who had colorectal surgery.
The researchers recruited 626 people ages 31 to 80 with the PIK3 mutation to participate. The PIK3 mutation is a common mutation and can carry a higher risk for recurrence.
The participants were randomly assigned to take aspirin or a placebo after surgery. The aspirin dose was 160 milligrams (mg), which is less than the dose recommended for treating a headache.
They had follow-up appointments, either by phone or in person, every 3 months for 3 years. The participants also had imaging taken periodically to monitor for recurrence.
Aspirin linked to significantly lower colorectal cancer recurrence
The study has staggering results for reducing the risk of cancer recurrence in people with colorectal cancer with the PIK3 mutation.
The participants who were randomly assigned to aspirin had a 55% lower risk of recurrence compared with the people who received a placebo.
The study found that colorectal cancer came back in 7.7% of aspirin users with hotspot PIK3 mutations, while recurrence was nearly double (14.1 to 16.8%) in the placebo group.
When conducting subgroup analyses, the study authors said the benefits were especially strong among women. They were unsure why aspirin was more effective for women and said it needs to be studied further.
The researchers suspect aspirin helped in people with PIK3 mutation due to reducing inflammation and disrupting the signaling that drives this type of cancer mutation.
Overall, the trial results show that not only can aspirin be effective at reducing recurrence in people with the PIK3 mutation in colorectal cancer, but it also emphasizes the need to tailor treatments in people with a genetic mutation.
A pathway to personalizing colorectal cancer treatment?
Anton Bilchik, MD, PhD, a surgical oncologist, chief of medicine, and Director of the Gastrointestinal and Hepatobiliary Program at Providence Saint John’s Cancer Institute, spoke with Medical News Today about the study and called the findings “potentially practice changing.”
“It is one of the first randomized trials to show that aspirin can improve survival in patients with colorectal cancer who express the PIK3C gene,” said Bilchik, who was not involved in this study. “This allows for personalizing treatment and knowing which patients are likely to benefit.”
Bilchik noted that patients would need to have their tumors checked for the PIK3 mutation to see if they would benefit from incorporating aspirin into their treatment and that they would also need to discuss aspirin safety with their providers.
He explained that:
“Aspirin is safe and has been shown to prevent colon polyps, but this study is one of the first to show that it can improve survival after being diagnosed with colorectal cancer. It is important, however, that patients discuss taking aspirin with their physicians because of the potential risks of developing gastritis or gastric bleeding.”
While aspirin is generally safe, it does increase the risk of gastrointestinal bleeding with regular use.
Joshua C. Lukenbill, MD, an oncologist with Mission Cancer + Blood, a part of University of Iowa Health Care, also discussed the findings with MNT.
“This is especially important given the high incidence of colon cancers and changing demographics, impacting younger patients without traditional risk factors,” Lukenbill, who was likewise not involved in the study, said of the findings.
Lukenbill expressed the need for more research to see exactly how aspirin reduces the recurrence rate in colorectal cancer and also included a word of caution about aspirin.
“Note that low-dose aspirin is not as benign as one may think,” he warned. “Serious adverse events — mainly related to bleeding — were seen in 5.2% more of the aspirin group than the placebo group.”
