Diagnostic and prognostic value of circulating tumor DNA in gastric cancer: a meta-analysis

// Yunhe Gao 1, * , Kecheng Zhang 1, * , Hongqing Xi 1, * , Aizhen Cai 1 , Xiaosong Wu 1 , Jianxin Cui 1 , Jiyang Li 1 , Zhi Qiao 1 , Bo Wei 1 , Lin Chen 1 1 Chinese PLA General Hospital, Department of General Surgery, Beijing, 100853, People’s Republic of China * These authors contributed equally to this work Correspondence to: Lin Chen, email: chenlinbj@sina.com Keywords: ctDNA, gastric cancer, diagnosis, prognosis, meta-analysis Received: September 26, 2016      Accepted: December 13, 2016      Published: December 21, 2016 ABSTRACT Background: Circulating tumor DNA (ctDNA) has offered a minimally invasive approach for detection and measurement of gastric cancer (GC). However, its diagnostic and prognostic value in gastric cancer still remains unclear. Results: A total of 16 studies comprising 1193 GC patients met our inclusion criteria. The pooled sensitivity and specificity were 0.62 (95% confidence intervals (CI) 0.59−0.65) and 0.95 (95% CI 0.93–0.96), respectively. The AUSROC (area under SROC) curve was 0.94 (95% CI 0.89–0.98). The results showed that the presence of certain ctDNA markers was associated with larger tumor size (OR: 0.26, 95% CI 0.11–0.61, p = 0.002), TNM stage (I + II/III + IV, OR: 0.11, 95% CI 0.07−0.17, p = 0.000), as well as H. pylori infection. ( H.p negative/ H.p positive, OR: 0.57, 95% CI 0.36–0.91, p = 0.018). Moreover, there was also a significant association between the presence of ctDNA and worse overall survival (HR 1.77, 95% CI 1.38−2.28, p < 0.001), as well as disease-free survival (HR 4.36, 95% CI 3.08−6.16, p < 0.001). Materials and Methods: Pubmed, Embase, Cochrane Library and Web of Science databases were searched for relating literature published up until November 30, 2016. Diagnostic accuracy variables were pooled by the Meta-Disc software. Engauge Digitizer and Stata software were applied for prognostic data extraction and analysis. Conclusions: Our meta-analysis indicates the detection of certain ctDNA targets is significantly associated with poor prognosis of GC patients, with high specificity and relatively moderate sensitivity.