Prognostic and predictive value of plasma d-dimer levels in patients with small-cell lung cancer

BackgroundTo investigate the predictive value of plasma d-dimer levels for short-term therapeutic effect and progression-free survival (PFS) in patients with small-cell lung cancer (SCLC); and to analyze the correlation between baseline plasma d-dimer levels and other clinicopathological features. The aim of the study was to investigate whether the levels of plasma d-dimer could serve as a predictive and prognostic factor in patients with SCLC.MethodsA retrospective review of the clinicopathological data of 160 patients with pathologically confirmed SCLC, who were treated at the Department of Thoracic Oncology of Tianjin Medical University Tumor Institute and Hospital between June 2011 and June 2016, was performed. At the same time, we collected 100 patients with benign pulmonary diseases as a control group. The correlations between baseline plasma d-dimer levels and other clinical features, therapeutic effect and PFS were analyzed statistically.ResultsThe level of plasma d-dimer in patients with SCLC was significantly higher than that of patients with benign pulmonary diseases (P=0.001). The PFS of patients with elevated d-dimer levels before therapy were significantly shorter than that of patients with normal d-dimer levels (6.0 versus 7.5months, P=0.013). The patients whose plasma d-dimer level always (before and after treatment) in the normal range have the best prognosis, and continuously elevated d-dimer carried out a poor prognosis (8.0 versus 5.0months). According to multivariate analysis, elevated d-dimer level was confirmed to be an independent prognostic factor for worse survival (P=0.029). The level of d-dimer was associated with tumor stage, the level of neuron-specific enolase, the presence of distant metastasis, hyponatremia, and the Karnofsky performance status score; and levels decreased when therapy was effective, but increased when the disease progressed.ConclusionsHigh levels of baseline plasma d-dimer may indicate advanced disease stage and poor prognosis. Therefore, plasma d-dimer levels could serve as a predictive and prognostic factor in patients with SCLC.