The ALASCCA trial found low-dose aspirin lowered 3-year colorectal cancer recurrence in tumors with PIK3CA changes (7.7% vs 14.1%). Aspirin also carries bleeding risks.
In the double-blind ALASCCA trial, 3-year recurrence in patients with PIK3CA hotspot mutations was 7.7% with aspirin versus 14.1% with placebo. The confidence interval was wide.
Severe adverse events were more common with aspirin (16.8% versus 11.6%) and aspirin carries real bleeding risks, so this is a conversation for your oncologist.
What if aspirin, a drug that's been around more than a hundred years, could cut the risk of cancer recurrence in half, but only in the right patients?
In 2025, the New England Journal of Medicine published a study looking at 3,000 patients treated with surgery for their colorectal cancer. And the results were pretty remarkable. More than 600 eligible patients were randomized to aspirin or placebo for three years. About 37% had alterations in genes involving the PI3K pathway. The aspirin dose was 160 milligrams daily.
Among patients with the specific hotspot mutations the researchers were primarily studying, cancer recurred within three years in 14.1% of the patients taking placebo, but with aspirin, almost half the recurrence rate at 7.7%. That's a 51% relative reduction in recurrence.
Now, aspirin's not harmless. Serious adverse events were more common with aspirin, 16.8% versus 11.6%. And these results apply to biomarker-selected colorectal cancer, not every cancer patient.
But this is where oncology may be headed. Not simply asking, does aspirin fight cancer? But whose cancer has a biology that makes aspirin's risk worth it?
Here's the research. You decide.
Educational research summary, not medical advice. Talk with your oncologist and pharmacist before starting, stopping or changing any treatment or supplement.