Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Feb 21, 2017; 23(7): 1310-1318
Published online Feb 21, 2017. doi: 10.3748/wjg.v23.i7.1310
Prognostic value of circulating tumor cells in esophageal cancer
Hai-Tao Xu, Jing Miao, Jian-Wei Liu, Lian-Guo Zhang, Qing-Guang Zhang
Hai-Tao Xu, Jian-Wei Liu, Lian-Guo Zhang, Qing-Guang Zhang, Department of Thoracic Surgery, Affiliated Hospital of Binzhou Medical University, Binzhou 256603, Shandong Province, China
Jing Miao, Department of Neonatal Intensive Care Unit, Binzhou People’s Hospital, Binzhou 256603, Shandong Province, China
Author contributions: Xu HT and Miao J contributed equally to this work as co-first authors; Xu HT designed the research, analyzed the data and wrote the manuscript; Miao J designed the research, analyzed the data and wrote the manuscript; Liu JW performed the research and contributed analytical tools; Zhang LG performed the research; Zhang QG conceived and designed the research, and revised the manuscript as corresponding author.
Conflict-of-interest statement: The authors declare that this is no conflict of interest related to this study.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Correspondence to: Qing-Guang Zhang, MD, Department of Thoracic Surgery, Affiliated Hospital of Binzhou Medical University, No. 661, Huanghe Erlu, Binzhou 256603, Shandong Province, China.
Telephone: +86-543-3258731 Fax: +86-543-3257792
Received: December 19, 2016
Peer-review started: December 21, 2016
First decision: January 10, 2017
Revised: January 20, 2017
Accepted: February 7, 2017
Article in press: February 8, 2017
Published online: February 21, 2017

To perform a meta-analysis of the related studies to assess whether circulating tumor cells (CTCs) can be used as a prognostic marker of esophageal cancer.


PubMed, Embase, Cochrane Library and references in relevant studies were searched to assess the prognostic relevance of CTCs in patients with esophageal cancer. The primary outcome assessed was overall survival (OS). The meta-analysis was performed using the random effects model, with hazard ratio (HR), risk ratio (RR) and 95% confidence intervals (95%CIs) as effect measures.


Nine eligible studies were included involving a total of 911 esophageal cancer patients. Overall analyses revealed that CTCs-positivity predicted disease progression (HR = 2.77, 95%CI: 1.75-4.40, P < 0.0001) and reduced OS (HR = 2.67, 95%CI: 1.99-3.58, P < 0.00001). Further subgroup analyses demonstrated that CTCs-positive patients also had poor OS in different subsets. Moreover, CTCs-positivity was also significantly associated with TNM stage (RR = 1.48, 95%CI: 1.07-2.06, P = 0.02) and T stage (RR = 1.44, 95%CI: 1.13-1.84, P = 0.003) in esophageal cancer.


Detection of CTCs at baseline indicates poor prognosis in patients with esophageal cancer. However, this finding relies on data from observational studies and is potentially subject to selection bias. Prospective trials are warranted.

Keywords: Circulating tumor cells, Esophageal cancer, Prognosis, Meta-analysis

Core tip: The clinical validity of circulating tumor cells (CTCs) is still controversial and inconclusive in patients with esophageal cancer. Our meta-analysis provides strong evidence that detection of CTCs in peripheral blood at baseline is an independent prognosticator of poor survival outcomes in esophageal cancer patients.