Aspirin Fails to Prevent Recurrence in Colorectal Cancer Liver Metastases Patients
Daily low-dose aspirin fails to lower the risk of cancer returning after surgical removal or destruction of colorectal cancer that has spread to the liver, medicalxpress.com reported.
- The phase 3 ASAC trial tested 160 mg of daily aspirin against a placebo in 466 randomized patients across 14 hospitals in Norway, Sweden, and Denmark.
- Results showed no statistically significant improvement in disease-free survival for patients taking aspirin following curative-intent treatment for liver metastases.
- Serious adverse events occurred more frequently in the aspirin group, leading researchers to conclude that the medication should not be routinely recommended in this clinical setting.
Colorectal cancer frequently spreads to the liver during the progression of the disease. While surgery or local ablation can remove these liver metastases with the intent of a cure, the cancer returns in most patients. Previous observational studies suggested that regular aspirin use might improve survival and lower recurrence rates. To test this hypothesis definitively, researchers launched the randomized, double-blind, placebo-controlled ASAC trial.
The trial enrolled 466 patients across 14 medical centers in Norway, Sweden, and Denmark who had completed treatment for liver metastases. Participants received either 160 mg of aspirin daily or an identical placebo for up to three years. According to final trial results published in The Lancet Gastroenterology & Hepatology, aspirin did not reduce the recurrence of cancer compared to the placebo group.
The median time before the cancer returned or a patient died was 1.13 years in the aspirin cohort and 1.40 years in the placebo cohort, a difference that researchers noted was not statistically significant. Serious adverse events were more common among patients assigned to take aspirin.
Investigators also observed a lower overall survival rate at three years in the aspirin group, with 75.7% of patients surviving compared to 84.9% in the placebo group. However, trial authors urged caution regarding this survival metric. Because overall survival was a secondary endpoint, the study was not primarily designed to measure it, and researchers did not track subsequent treatments administered after the cancer recurred.
The lack of efficacy in liver metastasis patients contrasts with findings from other recent investigations. The Scandinavian ALASCCA trial found that aspirin reduced recurrence in a subset of patients with localized primary colorectal cancer whose tumors carried specific alterations in the PI3K signaling pathway. However, the ASAC trial found no such benefit for patients with liver metastases, even among those with specific molecular alterations.
Sheraz Yaqub noted that findings from localized primary tumors cannot be directly applied to metastatic disease. He emphasized that patients already taking aspirin for cardiovascular indications or other medical conditions should not discontinue their regimen without consulting their physician.
Disclaimer: The information provided in this article is for educational and scientific communication purposes only and does not constitute medical advice.