Diagnostic and prognostic value of plasma D-dimer levels for metastasis and survival in gastric cancer: A systematic review and meta-analysis.

e16089 Background: Gastric cancer (GC) is frequently associated with hypercoagulability, yet the clinical utility of D-dimer as a biomarker remains inconsistent. While elevated D-dimer is linked to venous thromboembolism, its potential to predict distant metastasis and long-term survival in GC is debated. We performed a systematic review and meta-analysis to evaluate the diagnostic accuracy of pretreatment D-dimer for detecting metastasis and its prognostic value for overall survival (OS). Methods: We searched PubMed, Embase, and Cochrane Library databases through January 2026 for observational studies evaluating D-dimer in histologically confirmed GC. Inclusion criteria were studies reporting diagnostic performance (sensitivity/specificity) for metastasis or hazard ratios (HR) for survival. Quality was assessed using QUADAS-2 and NOS. A bivariate random-effects model was used to pool diagnostic metrics. Due to heterogeneous reporting of survival outcomes, prognostic data were synthesized qualitatively. Results: Eight studies comprising 6,189 patients were included. Four studies (n = 5,008) provided extractable data for diagnostic meta-analysis of metastasis (hematogenous, lymph node, or bone). The pooled sensitivity and specificity of elevated D-dimer for detecting metastasis were 0.67 (95% CI, 0.66-0.69) and 0.78 (95% CI, 0.77-0.79), respectively. The diagnostic odds ratio (DOR) was 7.40, indicating patients with metastasis had 7-fold higher odds of elevated D-dimer. The area under the summary receiver operating characteristic curve (SROC AUC) was 0.81, indicating moderate-to-high diagnostic accuracy. Regarding prognosis, 5 studies assessed survival outcomes. Elevated pretreatment D-dimer was universally associated with shorter OS in univariate analyses (P < 0.001). However, multivariate results were mixed: two studies confirmed D-dimer as an independent prognostic factor for 1-year mortality and OS, whereas two others found it dependent on tumor stage. D-dimer levels consistently correlated with tumor load, TNM stage, and vascular invasion. Conclusions: Pretreatment plasma D-dimer demonstrates high specificity and moderate sensitivity for detecting metastasis in gastric cancer, making it a viable, cost-effective initial screening tool. While consistently associated with poor survival, its independent prognostic value varies by study population. Routine D-dimer assessment may aid in risk stratification for occult metastasis. Diagnostic performance of d-dimer for gastric cancer metastasis. Study N Cut-off (mg/L) Sensitivity (%) Specificity (%) AUC (95% CI) Zhang X et al. 2022 3,447 0.91 68.2 76.3 0.77 (0.76–0.79) Wang et al. 2023 454 1.03 69.0 72.8 0.76 (0.71–0.80) Yan et al. 2025 65 1.63 87.1 94.1 0.91 (0.83–0.99) Diao et al. 2014 1,042 1.50 61.9 86.6 0.80 (0.76–0.83)