Blood transfusion might not be recommended for gastric cancer patients with pretransfusion minimum hemoglobin values higher than 90 g/L: a real-world study covering 20 years of 13470 patients

Background: There was no consistent evidence whether perioperative blood transfusion (PBT) affects the long-term survival of gastric cancer (GC) patients after undergoing gastrectomy. This study aimed to investigate the effects of PBT on long-term survival of GC patients, as well as to determine the threshold of PBT and provide evidence for future surgical practice. Methods: We performed this real-world study of GC patients undergoing gastrectomy in China National Cancer Center from January 1, 2000 to December 30, 2019. Overall survival (OS) curves were plotted using the Kaplan-Meier method and compared statistically using the log-rank test. Univariate and multivariate Cox proportional hazards models were used to determine the risk factors for OS. Results: In total, 13470 GC patients undergoing gastrectomy from 2000 to 2019 was included, of whom 3465 (34.6%) GC patients received PBT. PBT ratios declined from 29.1% (114/392) in 2000 to 11.2% in 2019 (149/1178), with the highest blood transfusion ratio in 2005 at 43.7% (220/504). For patients transfused with red blood cells, the median value of hemoglobin (Hb) before transfusion in the PBT group decreased from 110 g/L in 2000 to 87 g/L in 2019. Compared with patients who not receiving perioperative blood transfusion (NPBT), PBT group are more likely to be older (≥65, 39.1% vs. 30.1%, P <0.001), open operation (89.7% vs. 78.1%, P <0.001), higher ASA score (>2, 25.3% vs. 14.9%, P <0.001) and in the later pTNM stage (pTNM stage III, 68.5% vs. 51.5%, P <0.001). Results of multivariable Cox regression analysis showed that PBT was an independent prognostic factor for worse OS in GC patients undergoing gastrectomy (HR=1.106, 95% CI, 1.01-1.211, P =0.03). After stratified according to tumor stage, we found that PBT group had a worse prognosis only in pTNM stage III (HR=1.197, 95% CI, 1.119-1.281, P <0.001). OS was obviously poor in the PBT group when Hb levels were higher than 90 g/L (90 g/L<Hb≤120 g/L:HR=1.196, 95% CI,1.090-1.313, P <0.001; Hb>120 g/L:HR= 1.207, 95% CI, 1.098-1.327, P <0.001), while there was no difference between the two groups when Hb levels were lower than or equal to 90 g/L (Hb≤90 g/L: HR=1.162, 95% CI, 0.985-1.370, P =0.075). Conclusion: In conclusion, PBT was an independent prognostic factor for worse OS. Blood transfusion might not be recommended for gastric cancer patients with perioperative minimum Hb values higher than 90 g/L.