Effectiveness of managing suspected metastasis using plasma D-dimer testing in gastric cancer patients

Tumor metastasis is closely related to the coagulation system. Tumor metastasis and hypercoagulability promote each other through multiple mechanisms. However, whether coagulation indicators can reflect tumor metastasis remains to be explored. Clinical characteristics of a total of 3447 patients from three tertiary referral centers were collected. Then the diagnostic efficacy of FDP, D-dimer and GC tumor markers [Carcinoembryonic antigen (CEA), Carbohydrate antigen 19-9 (CA19-9) and Carbohydrate antigen 72-4 (CA72-4)] for GC metastases was evaluated by the receiver operating characteristic curve (ROC) analyses. Then we conducted a joint ROC curve analysis. The effects of coagulation parameters and tumor markers on gastric cancer metastasis were assessed using multiple logistic regression analysis. 2049 patients were diagnosed with primary GC, 1398 patients with metastatic GC. Based on comparison of AUC, FDP (cutoff, 1.915) had significantly higher diagnostic efficacy than fibrinogen (P<0.001), CEA (P<0.001), CA199 (P<0.001) and CA724 (P<0.001). No significant difference was observed between D-dimer (cutoff, 0.905) and FDP (P=0.158). The AUC of tumor markers combined with coagulation indexes was higher than that without combination (P<0.001). In multiple logistic regression analysis, age, smoking, D-dimer, FDP, CEA, CA19-9, CA72-4 were found to be significantly associated with GC metastasis (all P<0.001, except for smoking P=0.004). We conclude that plasma FDP and D-dimer may be novel clinical biomarkers for screening metastases of GC.