Perioperative blood transfusion affects oncologic outcomes after nephrectomy for renal cell carcinoma: A systematic review and meta-analysis

Aim: To investigate the association of perioperative blood transfusion (PBT) with oncologic outcomes in patients with renal cell carcinoma (RCC), we conducted a systematic review and meta-analysis of the literature to clarify the long-term oncologic effect of PBT in patients undergoing nephrectomy for RCC. Materials and methods: We searched the MEDLINE, Web of Science, Cochrane Library and Scopus on 15th April 2018 to identify studies that compared patients who received PBT undergoing radical or partial nephrectomy for RCC to patients who did not with the aim of evaluating its impact on overall mortality (OM), cancer-specific mortality (CSM) and disease recurrence using multivariable cox regression analysis. Results: A total of 19,681 patients in 7 studies matched the selection criteria for the systematic review and meta-analysis. All 7 studies were retrospective design and published between 1994 and 2018. Our study included low quality of eligible studies due to their retrospective design and showed a significant heterogeneity. PBT was associated with OM (pooled hazard ratio [HR], 1.49, 1.24–1.78), CSM (pooled HR, 1.46, 1.20–1.77), and disease recurrence (pooled HR, 1.80, 1.03–3.12). In a subgroup analysis of 3,664 patients with nonmetastatic RCC, PBT was remained associated with OM (pooled HR, 1.91; 1.06–3.41), but not anymore with CSM (pooled HR, 1.92, 0.94–3.91) or disease recurrence (pooled HR, 2.18, 0.86–5.55). Conclusions: PBT in patients undergoing nephrectomy for RCC is associated with worse overall survival. While PBT may be reflective of the underlying aggressiveness of the disease, it could be that its detrimental effect on outcomes is caused by its negative effect on the host's resilience.