title: Perioperative blood transfusion: does it influence survival and cancer progression in metastatic spine tumor surgery?
abstract: Despite advances in surgical techniques for spinal metastases, there is often substantial blood loss, resulting in patients requiring blood transfusion during the perioperative period. Allogeneic blood transfusion (ABT) has been the main replenishment method for lost blood. However, the impact of ABT on cancer-related outcomes has been controversial in various studies. We aimed to evaluate the influence of perioperative ABT on disease progression and survival in patients undergoing metastatic spinal tumor surgery (MSTS).
  
  
  
  We conducted a retrospective study that included 247 patients who underwent MSTS at a single tertiary institution between 2005 and 2014. The impact of using perioperative ABT (either exposure to or quantities of transfusion) on disease progression and survival was assessed using Cox regression analyses while adjusting for potential confounding variables.
  
  
  
  Of 247 patients, 133 (54%) received ABT. The overall median number of blood units transfused was 2 (range, 0-10 units). Neither blood transfusion exposure nor quantities of transfusion were associated with overall survival (hazard ratio [HR], 1.15 [p = 0.35] and 1.10 [p = 0.11], respectively) and progression-free survival (HR, 0.87 [p = 0.18] and 0.98 [p = 0.11], respectively). The factors that influenced overall survival were primary tumor type and preoperative Eastern Cooperative Oncology Group performance status, whereas primary tumor type was the only factor that had an impact on progression-free survival.
  
  
  
  This is the first study providing evidence that disease progression and survival in patients who undergo MSTS are less likely to be influenced by perioperative ABT. The worst oncologic outcomes are more likely to be caused by the clinical circumstances necessitating blood transfusion, but not transfusion itself. However, because ABT can have a propensity toward developing postoperative infections, including surgical site infection, the use of patient blood management interventions would be worthwhile rather than relying solely on ABTs for these patients, if and whenever possible.
authors.affiliation: Department of Orthopaedic Surgery, National University Hospital.
authors.forename: Aye Sandar
authors.initials: AS
authors.lastname: Zaw
authors.affiliation: Department of Orthopaedic Surgery, National University Hospital.
authors.forename: Shashidhar B
authors.initials: SB
authors.lastname: Kantharajanna
authors.affiliation: Department of Orthopaedic Surgery, National University Hospital.
authors.forename: Karthikeyan
authors.initials: K
authors.lastname: Maharajan
authors.affiliation: Department of Orthopaedic Surgery, National University Hospital.
authors.forename: Barry
authors.initials: B
authors.lastname: Tan
authors.affiliation: Radiation Oncology, National Cancer Institute of Singapore, Singapore.
authors.forename: Balamurugan
authors.initials: B
authors.lastname: Vellayappan
authors.affiliation: Department of Orthopaedic Surgery, National University Hospital.
authors.forename: Naresh
authors.initials: N
authors.lastname: Kumar
mesh_terms: D000368:Aged; D001803:Blood Transfusion; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D019990:Perioperative Care; D012189:Retrospective Studies; D012307:Risk Factors; D013125:Spinal Neoplasms / Q000401:mortality / Q000473:pathology / Q000556:secondary / Q000628:therapy; D015996:Survival Rate