Published online Aug 28, 2016. doi: 10.3748/wjg.v22.i32.7175
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.
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.