Objective: Lung cancer is one of the main causes of cancer-related mortality. The
identification of early diagnostic biomarkers improved outcomes for lung cancer patients. This study
investigated the correlation of preoperative plasma fibrinogen level with distant metastasis and
prognosis in lung cancer patients.
Methods: A total of 139 lung cancer patients who underwent curative surgery between January 2009
and November 2010 were enrolled in this study. In addition to clinical and pathological prognostic
factors, we evaluated the prognostic value of plasma fibrinogen on distant metastasis and relapse.
Univariate analysis was performed using the Kaplan-Meier survival analysis and multivariate
analysis was performed using the Cox regression model in order to measure 5-year distant metastasisfree
survival (DMFS), locoregional relapse-free survival (LRFS), relapse-free survival (RFS), and
overall survival (OS).
Results: Median plasma fibrinogen level was 3.59 g/L (range: 1.92-8.73 g/L). A total of 86 patients
(61.9%) had normal plasma fibrinogen levels (<4 g/L) and 53 patients (38.1%) had hyperfibrinogenemia
(>4 g/L). Pearson’s chi-square test showed that plasma fibrinogen level was significantly associated
with age (P=0.047), tumor stage (P<0.001), and lymph node status (P=0.037) whereas there was no
significant association between plasma fibrinogen level and gender, smoking, alcohol, tumor size,
and tumor differentiation. Median follow-up time was 37 months. The 5-year DMFS, LRMFS, RFS,
and OS rates were 26.40, 18.90, 7.50, and 28.30% with hyperfibrinogenemia respectively. Multivariate
analysis showed that lymph node status (P=0.001, HR=0.397 with 95% CI=0.233-0.677) and plasma
fibrinogen level (P=0.002, HR=0.410 with 95% CI=0.234-0.718) were significantly related to LRFS.
RFS was significantly related to plasma fibrinogen level (P=0.036, HR=0.596 with 95% CI=0.368-
0.966) and lymph node status (P<0.001, HR=0.405 with 95% CI=0.260-0.631). DMFS was also
significantly related to lymph node stage (P=0.006, HR=0.501 with 95% CI=0.307-0.817) and
plasma fibrinogen level (P=0.001, HR=0.399 with 95% CI=0.236-0.674).
Conclusion: Preoperative increased plasma fibrinogen level was a predictor of distant metastasis and
was independently associated with the prognosis of lung cancer patients.