Background: Blood transfusion has been associated with decreased long-term survival in cancer patients, possibly due to various immunological factors. We aimed to evaluate if perioperative transfusions decrease survival in patients who undergo resection for esophageal or gastric cancer and to identify factors associated with such events.

Methods: A population-based cohort study was conducted based on the Swedish National Registry for Esophageal and Gastric Cancer, which prospectively collects clinical data of patients with these tumors. Almost all patients (96 %) resected for esophageal or gastric cancer in Sweden between 2017 and 2022 were included. Survival data were acquired from the Swedish Cause of Death Registry. Multivariable Cox regression was used to calculate hazard ratios (HR) with 95 % confidence intervals (CI), adjusted for age, fitness, neoadjuvant therapy, surgical access, and pathological TNM stage.

Results: Of all 1365 patients, 227 (17 %) received perioperative transfusions. Transfusion was associated with an increased risk of all-cause mortality within 3 years of surgery (adjusted HR 1.50, 95 % CI 1.17-1.91). To exclude the influence of surgery-related postoperative complications, a sensitivity analysis was performed excluding patients who died within 30 days of resection and the negative impact of transfusions on 3-year mortality remained (adjusted HR 1.30, 95 % CI 1.01-1.68). Increasing age, open surgery, esophagectomy, perioperative bleeding, and nodal tumor involvement were all associated with an increased likelihood of receiving transfusions.

Conclusion: Perioperative blood transfusions might have a negative impact on 3-year survival in patients who undergo surgery for esophageal or gastric cancer.