Can Aspirin Help Prevent Colorectal Cancer?

According to the American Cancer Society, colorectal cancer is the second most common cause of cancer deaths among men and women. Colorectal cancer starts as benign cells that grow inside the colon or the rectum. The cells, also referred to as polyps, can turn into cancer over time if they’re not removed. These cancerous cells may spread to other parts of the body.

A Mass General Brigham-led study, published in JAMA Oncology, reports that daily low-dose use of aspirin may help lower the risk of colorectal cancer, particularly for those with less healthy lifestyles. The researchers studied more than 100,000 people, and results showed that people who had several lifestyle-related risk factors for colorectal cancer benefited from taking aspirin.

“Our results show that aspirin can proportionally lower the markedly elevated risk in those with multiple risk factors for colorectal cancer,” says Daniel Sikavi, MD, lead author of the study and a gastroenterologist at Massachusetts General Hospital. “In contrast, those with a healthier lifestyle have a lower baseline risk of colorectal cancer, and, therefore, their benefit from aspirin was still evident, albeit less pronounced.”

Dr. Sikavi co-authored the research with Andrew T. Chan, MD, MPH, director of epidemiology at Mass General Cancer Center and gastroenterology director of the Center for Young Adult Colorectal Cancer at Massachusetts General Hospital, and Long H. Nguyen, MD, MS, a Mass General Brigham gastroenterologist and investigator in the Clinical and Translational Epidemiology Unit and Division of Gastroenterology at Mass General.

Aspirin and colorectal cancer prevention: Regular use may reduce cancer risk

The study shows that regular aspirin use may reduce the risk of colorectal cancer by 18% compared to non-regular use.

The research forms part of an effort to encourage a more nuanced approach to aspirin in cancer prevention. The Mass General Brigham researchers compared the outcomes of participants who took aspirin regularly with those who did not take aspirin regularly. Participants formed part of the Nurses’ Health Study and Health Professionals Follow-Up Study. Previously, the U.S. Preventive Services Task Force (USPSTF) withdrew the recommendation of taking a daily low-dose of aspirin to prevent cardiovascular risks and colorectal cancer due to concerns about the risk of gastrointestinal bleeding. 

Aspirin, as the new Mass General Brigham study reveals, may reduce the uncontrolled growth of cells in the colon or rectum that can cause cancer. “Aspirin likely prevents colorectal cancer through multiple mechanisms,” Dr. Chan says.

“We sought to identify individuals who are more likely to benefit from aspirin to facilitate more personalized prevention strategies,” Dr. Chan explains. The researchers also assessed other factors like diet, lifestyle, medical history, and disease outcomes.

The researchers observed a greater benefit of aspirin in people with a less healthy lifestyle. These included people with high body mass index (BMI), frequent cigarette and alcohol use, less physical activity, and poorer quality of diet.

“Health care providers might more strongly consider recommending aspirin to patients who have less healthy lifestyles,” said Dr. Nguyen. 

Should I take aspirin to help prevent colorectal cancer?

Talk to your primary care provider before taking any new medication, including aspirin. They can help you understand if it’s a good choice for you based on your medical history, risk for colorectal cancer, lifestyle, and possible side effects or interactions with other medications you take.

Most people take aspirin as an over-the-counter medicine to relieve pain from mild aches and pains such as those common with mild arthritis, or menstrual periods. Aspirin also can reduce fever. When used as a prescription drug, aspirin can relieve pain from osteoarthritis, and lupus. Some patients with a history of heart attacks and strokes take aspirin to help prevent blood clots or clot growth.

What are the causes of colorectal cancer?

Colorectal cancer is associated with mutations, or changes in the genetic material (DNA). It is yet unclear why these mutations occur. It also can be associated with family history and it’s possible to be born with this DNA. Changes in DNA can happen during a person’s lifetime. Doctors have found other risk factors, but it is not yet known how they are related to the genes.

What are colorectal cancer risk factors?

According to the Centers for Disease Control and Prevention (CDC), some risk factors associated with contributing to colorectal cancer are:

• Lack of exercise
• A diet low in fruits, vegetables, and fiber
• A diet high in fat and processed meats
• Obesity
• Consumption of alcohol
• Smoking
• A family or personal history of colorectal cancer
• Crohn's disease or ulcerative colitis

Tips to prevent colorectal cancer

Other ways to reduce the risk of getting colorectal cancer include:

• Eat less red meat.
• Exercise more.
• Don’t drink alcohol.
• Keep a healthy weight.
• Quit smoking.

Colorectal cancer screenings

Getting colorectal cancer screenings can help catch cancer early, when it’s easier to treat. Talk to your PCP about colorectal cancer screenings based on your family history and medical history.