The prognostic importance of red blood cell distribution width for gastric cancer: a systematic review and meta-analysis

Background: For cancer patients, red blood cell distribution width (RDW) is a readily accessible and cost-effective preoperative prognostic predictor. This study aimed to determine whether RDW is a predictive factor for individuals undergoing radical surgery for gastric cancer (GC). Methods: A literature search was performed to select relevant studies for inclusion in the subsequent meta-analysis. Relevant data were pooled to assess the association between RDW and GC results, including overall survival (OS), disease-free survival (DFS), and cancer-specific survival (CSS), as well as clinicopathological features. Results: The meta-analysis and systemic review included data from 8 studies comprising 1,587 individuals diagnosed with GC. In this context, RDW refers to the coefficient of variation of RDW (RDW-CV). A high level of RDW-CV was significantly associated with older age [odds ratio (OR) =2.25; 95% confidence interval (CI): 1.72–2.94; P<0.00001], larger tumor diameter (OR =1.90; 95% CI: 1.42–2.56; P<0.0001), and vascular invasion (OR =2.22; 95% CI: 1.10–4.49; P=0.03). After hazard ratios (HRs) and 95% CIs were pooled, RDW-CV was found to be an independent prognostic factor of OS (HR =1.79; 95% CI: 1.21–2.66; I2=85%; P=0.004), DFS (HR =1.81; 95% CI: 1.37–2.39; I2=0%; P<0.0001), and CSS (HR =2.73; 95% CI: 1.36–5.49; I2=0%; P=0.005) in patients with GC. Conclusions: The association between high levels of RDW-CV and poor survival in GC suggests that RDW-CV may be a viable prognostic indicator for patients with GC.