Abstract
BACKGROUND: Elevated plasma fibrinogen (Fbg) levels contribute to tumor progression and metastasis; however, limited research on Fbg in small cell lung cancer (SCLC) has been conducted. This study evaluated the prognostic value of Fbg levels in patients with SCLC. METHODS: Data on plasma Fbg level, clinical features, and overall survival were retrospectively collected. Kaplan-Meier estimates and log-rank tests were used to analyze the relationship between Fbg level and survival. Multivariate analyses were performed to determine independent prognostic factors. Subgroup analyses were performed based on extensive/limited disease and Eastern Cooperative Oncology Group status. RESULTS: A total of 120 patients with SCLC were included. The one, three, and five-year survival rates for the entire cohort were 48.3%, 9.2%, and 1.7%, respectively. Univariate analyses revealed that age, alcohol use, clinical stage, pleural effusion, Eastern Cooperative Oncology Group grade, and Fbg and lactate dehydrogenase levels were associated with survival (P < 0.05). The median survival time for patients with high Fbg levels (> 400 mg/dL) was shorter than for those with low Fbg levels (8 vs. 14 months; P = 0.013). Furthermore, multivariate analysis revealed that Fbg was negatively and independently associated with SCLC prognosis (hazard ratio 1.505, 95% confidence interval 1.018-2.226; P = 0.041). Higher Fbg levels were associated with shorter survival in the extensive disease subgroup (7 vs. 12 months; P = 0.004). CONCLUSIONS: Elevated plasma Fbg was an independent factor associated with poor outcomes in SCLC patients and could serve as a prognostic biomarker.