A new study published in the Oct. 25 New England Journal of Medicine suggests that aspirin, one of the world’s oldest and cheapest drugs, may be an effective treatment for fighting colon cancer in people whose tumors have a specific genetic mutation.
“Aspirin appears to work to increase survival of colorectal cancer patients if the tumor has PIK3CA mutation, but does not work if the tumor does not have PIK3CA mutation,” Dr. Shuji Ogino, study researcher and associate professor in the department of epidemiology at the Harvard School of Public Health, told HealthDay.
According to the Centers for Disease Control and Prevention (CDC), cancers of the colon and rectum are the second leading cause of cancer-related deaths in the United States. More than 140,000 cases and 52,000 deaths are expected this year in the U.S. About 20 percent of colorectal patients have PIK3CA.
Among the patients in the study who had the mutation, those who regularly took aspirin lived longer than those who didn’t. An Associated Press article published in the Oct. 24 Boston Herald reported that five years after patients’ cancers were diagnosed, 97 percent of those who took aspirin were still alive compared to 74 percent of those who did not take the drug.
Previous studies have suggested that aspirin may help fight cancer, especially colorectal tumors. However, because the drug can produce serious stomach bleeding, it has not been widely used as a cancer treatment or prevention option.
The new study, sponsored by the National Institutes of Health (NIH) and led by Dr. Andrew Chan, assistant professor of medicine, gastroenterology, Massachusetts General Hospital (MGH), and others from Harvard Medical School, was meant to determine who would benefit most from aspirin treatment to justify using the drug.
The study involved 964 participants who had colorectal cancer, and who were a part of two Harvard-based studies, the Nurses’ Health Study and the Health Professionals Follow-up Study, that began in the 1980s. Every two years, participants filled out surveys on their health habits, including the use of aspirin. Researchers focused on those with PIK3CA. As reported by Associated Press, among those with the mutation, regular aspirin use cut the risk of dying of colon cancer by 82 percent and of dying of any cause by 42 percent during the 13-year study period. The dose – baby or regular aspirin – did not seem to matter.
Researchers, however, caution that aspirin may not be entirely responsible for the improved survival rates seen in the study results. Differences in how patients’ cancer was treated, including surgery and chemotherapy, may have played a role.
The next step, they say, is to include in a study only those who have the PIK3CA mutation and give aspirin to some and not others to validate the current findings.
Still, researchers are cautiously optimistic about the possibility that a readily available drug may be the cheapest gene-targeting therapy ever used for cancer.
“It’s exciting to think that something’s that’s already in the medicine cabinet may really have an important effect beyond relieving pain and helping to prevent heart attacks,” said MGH’s Chan.