['The aim of the present study was to investigate the relationship between the preoperative plasma fibrinogen level and the extent of tumor involvement in gastric cancer patients.', 'Preoperative plasma fibrinogen levels of 354 patients who underwent gastric cancer surgery were quantified using an immunoassay. The relationships between the plasma fibrinogen level and other prognostic variables (tumor size, macroscopic and histological type, depth of tumor invasion, presence of lymph node involvement and distant metastasis) were then examined using univariate and multivariate linear regression analyses.', 'The plasma fibrinogen level was significantly lower in patients with early gastric cancer than in those with advanced gastric cancer (312+/-6.7 vs. 361.9+/-97.0 mg/mL, p<0.001). A significant relationship existed between the preoperative fibrinogen levels and the presence of metastatic lymph nodes (320+/-78.6 vs. 352.6+/-94.1 mg/mL, p=0.001) and distant metastasis (338.2+/-89.5 vs. 396.9+/-128.3 mg/mL, p=0.013). Size of the tumors and depth of tumor invasion could predict elevated fibrinogen levels positively in both the univariate regression and multivariate linear regression analyses.'] Do preoperative plasma fibrinogen levels in gastric cancer patients correlate with extent of tumor?