Clinical features of pulmonary embolism in patients with lung cancer: A meta-analysis

Background
Pulmonary embolism (PE) is correlated with increased mortality among patients with lung cancer (LC). The characteristics of patients with LC presenting with PE have not been fully established, and our meta-analysis aims to comprehensively investigate the clinical characteristics associated with PE in patients with LC to help physicians identify PE earlier in these patients.
Methods
Multiple databases were searched, including PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure and Wanfang. Odds ratios (ORs) and weighted mean differences (WMDs) with 95% confidence intervals (95% CIs) were used as effect measures for dichotomous and continuous variables, respectively. Moreover, Egger’s test, Begg’s test and a sensitivity analysis were performed to assess the publication bias and reliability of the articles.
Results
In total, 16 studies were included in our meta-analysis. The results indicated that history of chronic obstructive pulmonary disease (OR = 2.59, 95% CI: 1.09, 6.15; P = 0.03), adenocarcinoma (OR = 2.28, 95% CI: 1.88, 2.77; P < 0.01), advanced tumour stage (TNM III-IV vs. I-II, OR = 2.38, 95% CI: 1.99, 2.86; P < 0.01), history of central venous catheter (OR = 1.95, 95% CI: 1.36, 2.78; P < 0.01), history of chemotherapy (OR = 2.32, 95% CI: 1.80, 2.99, P < 0.01), high levels of D-dimer (WMD = 4.31, 95% CI: 2.53, 6.10; P < 0.01) and carcinoembryonic antigen (WMD = 10.30, 95% CI: 9.95, 10.64; P < 0.01) and a low level of partial pressure of oxygen (WMD = -25.97, 95% CI: -31.31, -20.62; P < 0.01) were clinical features of LC patients with PE compared to those without PE.
Conclusions
These results reveal that LC patients with PE have specific clinical features, including but not limited to several cancer- and treatment-related factors, that may help their early identification.