Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. Jul 15, 2018; 10(7): 145-158
Published online Jul 15, 2018. doi: 10.4251/wjgo.v10.i7.145
Novel biomarkers for patient stratification in colorectal cancer: A review of definitions, emerging concepts, and data
Manish Chand, Deborah S Keller, Reza Mirnezami, Marc Bullock, Aneel Bhangu, Brendan Moran, Paris P Tekkis, Gina Brown, Alexander Mirnezami, Mariana Berho
Manish Chand, GENIE Centre, University College London, London W1W 7TS, United Kingdom
Deborah S Keller, Department of Surgery, Columbia University Medical Centre, New York, NY 10032, United States
Reza Mirnezami, Department of Surgery, Imperial College London, London SW7 2AZ, United Kingdom
Marc Bullock, Department of Surgery, University of Southampton, Southampton SO17 1BJ, United Kingdom
Aneel Bhangu, Department of Surgery, University of Birmingham, Birmingham B15 2QU, United Kingdom
Brendan Moran, Department of Colorectal Surgery, North Hampshire Hospital, Basingstoke RG24 7AL, United Kingdom
Paris P Tekkis, Department of Colorectal Surgery, Royal Marsden Hospital and Imperial College London, London SW3 6JJ, United Kingdom
Gina Brown, Department of Radiology, Royal Marsden Hospital and Imperial College London, London SW3 6JJ, United Kingdom
Alexander Mirnezami, Department of Surgical Oncology, University of Southampton and NIHR, Southampton SO17 1BJ, United Kingdom
Mariana Berho, Department of Pathology, Cleveland Clinic Florida, Weston, FL 33331, United States
Author contributions: All authors equally contributed to this paper with conception and design of the study, literature review and analysis, drafting and critical revision and editing, and final approval of the final version.
Conflict-of-interest statement: No potential conflicts of interest. No financial support.
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: Manish Chand, FRCS (Gen Surg), PhD, Associate Professor, Surgeon, Consultant Colorectal Surgeon and Senior Lecturer, GENIE Centre, University College London, Charles Bell House, 43 Foley Street, London W1W 7TS, United Kingdom.
Telephone: +44-20-34475879 Fax: +44-20-34479218
Received: March 8, 2018
Peer-review started: March 8, 2018
First decision: March 19, 2018
Revised: April 22, 2018
Accepted: June 8, 2018
Article in press: June 9, 2018
Published online: July 15, 2018

Colorectal cancer (CRC) treatment has become more personalised, incorporating a combination of the individual patient risk assessment, gene testing, and chemotherapy with surgery for optimal care. The improvement of staging with high-resolution imaging has allowed more selective treatments, optimising survival outcomes. The next step is to identify biomarkers that can inform clinicians of expected prognosis and offer the most beneficial treatment, while reducing unnecessary morbidity for the patient. The search for biomarkers in CRC has been of significant interest, with questions remaining on their impact and applicability. The study of biomarkers can be broadly divided into metabolic, molecular, microRNA, epithelial-to-mesenchymal-transition (EMT), and imaging classes. Although numerous molecules have claimed to impact prognosis and treatment, their clinical application has been limited. Furthermore, routine testing of prognostic markers with no demonstrable influence on response to treatment is a questionable practice, as it increases cost and can adversely affect expectations of treatment. In this review we focus on recent developments and emerging biomarkers with potential utility for clinical translation in CRC. We examine and critically appraise novel imaging and molecular-based approaches; evaluate the promising array of microRNAs, analyze metabolic profiles, and highlight key findings for biomarker potential in the EMT pathway.

Keywords: Biomarker, Colorectal cancer, Epithelial-to-mesenchymal-transition pathway, Molecular biomarker, MicroRNA, Metabolic biomarker, Imaging biomarker, Tumour regression grade

Core tip: Biomarkers are an emerging field that can potentially guide the diagnosis, prognosis, and treatment course in rectal cancer. Here, the current definitions, classifications, recent developments and emerging biomarkers with potential utility for clinical translation in colorectal cancer are reviewed by international experts for a better understanding in surgery.