Impact of perioperative blood transfusion on prognosis after nephrectomy in patients with renal cell carcinoma: A meta-analysis and systematic review

Background:Perioperative blood transfusion (PBT) has been associated with worse prognosis in several malignancies. For renal cell carcinoma (RCC), the effect of PBT is still debated.Objective:To evaluate the impact of PBT on prognosis after nephrectomy in patients with RCC.Methods:This study is A systematic review and meta-analysis of published article data (PRISMA protocol) for literature related to PBT and RCC through extensive search of EMBASE, Medline via PubMed, Web of Science and Cochrane Library, language limited to English, with no time constraint until May 20, 2022. We pooled the results of multivariable cox regression analyses from each study, with subgroup analyses by dose and timing of transfusion. All analyses were done using Stata14.Results:A total of 12 studies involving 27,683 participants were included. Our meta-analysis pooled the results of multivariable cox regression analysis in each study, showing that PBT is associated with higher overall Mortality (OM; hazard ratio [HR] = 1.34, 1.23-1.44), cancer-specific mortality (CSM; HR = 1.35, 1.20-1.51), and disease recurrence (HR = 1.54, 1.18-1.89). when only patients with nonmetastatic RCC were included, PBT was still associated with higher OM (HR = 1.29, 1.11-1.47) and disease recurrence (HR = 1.58, 1.18-1.98), but the association with CSM (HR = 1.26, 0.99-1.52) was not statistically significant. In subgroup analysis by transfusion dose, small (1-2) units of PBT were not associated with CSM (HR = 1.84, 0.95-2.73), but large (>= 3) units were associated with higher CSM (HR = 2.98, 1.74-4.22) and disease recurrence (HR = 1.99, 1.31-2.67). Each additional unit of PBT resulted in a higher CSM (HR = 1.07, 1.04-1.10). In subgroup analysis by transfusion timing, intraoperative transfusion was associated with higher CSM and disease recurrence, but postoperative transfusion was not.Conclusions:PBT is associated with higher OM, CSM and disease recurrence. This adverse effect seems to be particularly significant in high-dose intraoperative transfusion. It is necessary to limit the overuse of PBT, especially high-dose intraoperative transfusion, in order to improve the prognosis of patients undergoing nephrectomy for RCC.