Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Aug 28, 2016; 22(32): 7175-7185
Published online Aug 28, 2016. doi: 10.3748/wjg.v22.i32.7175
Pancreatic cancer: Are "liquid biopsies" ready for prime-time?
Alexandra R Lewis, Juan W Valle, Mairead G McNamara
Alexandra R Lewis, Juan W Valle, Mairead G McNamara, The Christie NHS Foundation Trust, M20 4BX Manchester, United Kingdom
Juan W Valle, Mairead G McNamara, Institute of Cancer Sciences, University of Manchester, M20 4BX Manchester, United Kingdom
Author contributions: Lewis AR reviewed articles and wrote the paper; Valle JW and McNamara MG contributed critical revision of the manuscript for important intellectual content.
Conflict-of-interest statement: No conflict of interest.
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: Dr. Mairead G McNamara, The Christie NHS Foundation Trust, 550 Wilmslow Road, M20 4BX Manchester, United Kingdom.
Telephone: +44-161-4463000
Received: April 27, 2016
Peer-review started: April 27, 2016
First decision: May 30, 2016
Revised: June 10, 2016
Accepted: July 6, 2016
Article in press: July 6, 2016
Published online: August 28, 2016

Pancreatic cancer is a disease that carries a poor prognosis. Accurate tissue diagnosis is required. Tumours contain a high content of stromal tissue and therefore biopsies may be inconclusive. Circulating tumour cells (CTCs) have been investigated as a potential “liquid biopsy” in several malignancies and have proven to be of prognostic value in breast, prostate and colorectal cancers. They have been detected in patients with localised and metastatic pancreatic cancer with sensitivities ranging from 38%-100% using a variety of platforms. Circulating tumour DNA (ctDNA) has also been detected in pancreas cancer with a sensitivity ranging from 26%-100% in studies across different platforms and using different genetic markers. However, there is no clear consensus on which platform is the most effective for detection, nor which genetic markers are the most useful to use. Potential roles of liquid biopsies include diagnosis, screening, guiding therapies and prognosis. The presence of CTCs or ctDNA has been shown to be of prognostic value both at diagnosis and after treatment in patients with pancreatic cancer. However, more prospective studies are required before this promising technology is ready for adoption into routine clinical practice.

Keywords: Pancreatic, Cancer, Liquid biopsy, Circulating, Tumour, Cells, Circulating tumour DNA

Core tip: Pancreatic cancer is a difficult disease to diagnose and treat. Persistently poor outcomes mean that new biomarkers of disease and treatments are required. Circulating tumour cells and circulating tumour DNA have been investigated as liquid biopsies in pancreatic cancer. Sensitivity is variable but specificity promising. The most effective platform and most informative biomarkers are yet to be identified. There are many potential roles for this technology in the management of patients with pancreatic cancer, including screening, diagnosis, prognosis and monitoring of treatment efficacy; however based on current available evidence they are not yet ready for routine clinical practice.