Abstract
BACKGROUND: Blood loss is a major perioperative concern in metastatic spine tumor surgery (MSTS). Allogeneic blood transfusion (ABT) remains the standard method of blood replacement but is associated with well-recognised complications. Salvaged blood transfusion (SBT) using intraoperative cell salvage may mitigate many of these risks; however, its oncological safety and long-term outcomes in MSTS remain controversial. METHODS: This was a prospective cohort study of patients who underwent MSTS between 2014 and 2017. Clinical outcomes included overall survival (OS) and tumor progression (TP), assessed using RECIST (version 1.1). A propensity score-matched cohort was generated using relevant predictors of treatment allocation and outcomes of interest to enable comparison between patients receiving SBT and ABT. RESULTS: A total of 98 patients (mean age 60 years) were included, of whom 33 received SBT, 39 received ABT, and 26 received no blood transfusion. Median estimated blood loss was 400 mL (IQR 200-900 mL), and median blood transfusion volume was 328.5 mL (IQR 0-1042 mL). Propensity score matching yielded 30 patients in the ABT group and 28 in the SBT group. There was no significant difference in overall survival between patients receiving SBT and ABT (p=.250). Importantly, SBT was not associated with an increased risk of 4-year TP (p=.908). CONCLUSIONS: SBT demonstrates comparable long-term survival and TP outcomes to ABT in patients undergoing MSTS, while avoiding the known complications associated with ABT. This study represents the first long-term propensity score-matched analysis of SBT in MSTS, supporting its oncological safety and clinical utility in contemporary spine oncology practice.