Studies have shown that the use of low-dose aspirin may reduce the incidence and mortality of cancer, but its impact on the survival of gastric adenocarcinoma is unclear. An international team conducted a related study to evaluate whether taking aspirin after gastric resection for gastric adenocarcinoma can improve long-term survival. The results were published in the journal Gastric Cancer.

This population-based cohort study included patients who underwent gastric resection for gastric adenocarcinoma in Sweden from 2006 to 2015 and was followed up throughout 2020. Exposure to daily low-dose (75-160 mg) aspirin one year, two years, three years before surgery and one year after gastric resection was associated with all-cause mortality at five years (primary outcome) and disease-specific mortality. Multivariable Cox regression analysis provided hazard ratios (HR) with 95% confidence intervals (CI), adjusted for age, sex, education level, year, comorbidities, statin use, tumor location, tumor stage, neoadjuvant chemotherapy, number of surgeons performing gastric resection, and radicality of the surgery.

Among the 2025 patients included in the study, 545 (26.9%) were using aspirin at the time of surgery. Among those taking aspirin, 178 (32.7%) did not take aspirin again after surgery. Approximately 56 (2.8%) patients started using aspirin within one year after gastric resection. Fifty-two (9.5%) aspirin users and 91 (6.2%) non-aspirin users died within 90 days of surgery.

Kaplan–Meier curves showed no statistically significant difference in survival between patients who took and did not take aspirin.

Use of aspirin within one year before surgery did not reduce the risk of adjusted all-cause mortality at five years (HR = 0.98, 95% CI 0.85-1.13) or disease-specific mortality (HR = 1.00, 95% CI 0.86-1.17).

Taking aspirin within 2 years before surgery (HR = 0.98, 95% CI 0.84-1.15) or within 3 years (HR = 0.94, 95% CI 0.79-1.12) did not reduce the risk of 5-year all-cause mortality. Similarly, patients who used aspirin preoperatively and postoperatively for 1 year did not show any reduction in 5-year all-cause mortality (adjusted HR=1.01, 95% CI 0.82-1.25).

In the sensitivity analysis, we excluded 291 patients (14.3%) who underwent gastric resection without a clear treatment purpose. Among the analysis of 1734 patients, the 90-day mortality rate was 4.0%. Compared to those who did not take aspirin, aspirin use was not associated with 5-year all-cause mortality (adjusted HR=0.92, 95% CI 0.78-1.09) or 5-year disease-specific mortality (adjusted HR=0.94, 95% CI 0.79-1.13).

In summary, the study suggests that the use of low-dose aspirin may not improve long-term survival after gastric adenocarcinoma surgery.