Low-dose aspirin reduces colorectal cancer recurrence in patients with a specific genetic mutation, Nordic trial finds
Randomized study across 33 hospitals shows a 55% drop in recurrence among patients with PI3K pathway alterations after tumor removal
A randomized trial across 33 hospitals in Sweden, Norway, Denmark and Finland found that a daily low-dose aspirin regimen significantly reduced colorectal cancer recurrence in a genetic subgroup of patients who had surgery to remove their tumors. The ALASCCA study followed more than 3,500 patients with colorectal cancer and focused on those whose tumors carried a somatic mutation in the PI3K signaling pathway. Among participants with the mutation, those given 160 milligrams of aspirin daily for three years experienced a 55% lower risk of cancer returning compared with a placebo group.
The trial, conducted by researchers from Karolinska Institutet and Karolinska University Hospital, included patients who had undergone surgical removal of their tumors. The aspirin duration, dosage, and the specific genetic marker were central to the study’s design, and the findings were published in the New England Journal of Medicine. The study’s investigators say the results highlight a potential pathway to combine a common, inexpensive drug with precision medicine in colorectal cancer care.
The lead author, Anna Martling, M.D., Ph.D., a professor at the Department of Molecular Medicine and Surgery at Karolinska Institutet and senior consultant surgeon at Karolinska University Hospital, said the trial demonstrates for the first time in a randomized setting that low-dose aspirin can meaningfully reduce recurrence in patients with somatic PI3K pathway alterations. “This applies to more than one-third of all patients with resected colorectal cancer,” she noted. The effect appeared to be stronger in women, a finding that Martling called worthy of further investigation.
Several caveats accompanied the results. The researchers acknowledged that the study was not powered for detailed subgroup analyses, and patients older than 80 were not included. Longer follow-up will be needed to determine whether the reduced recurrence translates into an overall survival benefit. Patients should not begin aspirin therapy outside a medical context, especially given possible side effects such as stomach problems and a higher bleeding tendency. Those with stomach ulcers, bleeding disorders or asthma, and individuals taking other blood-thinning agents or consuming significant amounts of alcohol, should exercise caution under medical supervision. In their view, the findings should inform clinical guidelines but require confirmation in broader practice.
The researchers underscored that the results are immediately relevant to clinicians and guideline committees. They suggested that testing for PI3K pathway alterations could become a standard consideration in colorectal cancer patients after surgery. Nevertheless, Martling emphasized that aspirin should not be used without physician oversight until guidelines and treating physicians adopt these findings. If implemented broadly, the regimen could prevent thousands of recurrences and save lives in settings where access to newer, expensive therapies is limited.
The study’s implications extend to precision medicine by showing how a well-known, low-cost drug can be repurposed for a genetically defined subset of patients. The inclusion of aspirin in a post-surgical plan for colorectal cancer could become a model for integrating molecular profiling with existing treatments, provided that follow-up studies corroborate the results and guidelines reflect the balance of benefits and risks.
Dr. Marc Siegel, a Fox News medical analyst who was not involved in the study, described aspirin as an anti-inflammatory agent that can influence growth factors and cancer risk. He pointed to prior observational work suggesting NSAIDs reduce colon cancer risk and mortality, while stressing the need to assess risks and benefits on a case-by-case basis. The PI3K pathway mutation studied here is associated with rapid cancer cell growth and is found in roughly 30% of colon cancers, according to the researchers.
The ALASCCA trial received support from the Swedish Research Council and the Swedish Cancer Society, highlighting continued investment in integrating high-technology platforms with established, affordable drugs to improve cancer outcomes.