Systematic Reviews
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Oct 7, 2016; 22(37): 8414-8434
Published online Oct 7, 2016. doi: 10.3748/wjg.v22.i37.8414
Defining response to radiotherapy in rectal cancer using magnetic resonance imaging and histopathological scales
Muhammed R S Siddiqui, Jemma Bhoday, Nicholas J Battersby, Manish Chand, Nicholas P West, Al-Mutaz Abulafi, Paris P Tekkis, Gina Brown
Jemma Bhoday, Manish Chand, Al-Mutaz Abulafi, Muhammed RS Siddiqui, Department of Colorectal Surgery, Croydon University Hospital, Croydon, London CR7 7YE, United Kingdom
Jemma Bhoday, Nicholas J Battersby, Gina Brown, Muhammed RS Siddiqui, Department of Radiology, Royal Marsden Hospital, Sutton SM2 5PT, United Kingdom
Nicholas P West, Pathology and Tumour Biology, Leeds Institute of Cancer and Pathology, St. James’s University Hospital, Leeds LS9 7TF, United Kingdom
Paris P Tekkis, Department of Surgery, Royal Marsden Hospital, Fulham Rd, London SM2 5PT, United Kingdom
Author contributions: Siddiqui MRS, Bhoday J and Battersby NJ performed the literature search; Siddiqui MRS and Brown G analysed the data; Chand M wrote and corrected the manuscript; Siddiqui MRS, West NP, Abulafi AM, Tekkis PP and Brown G wrote and corrected the manuscript and approved it for final submission.
Supported by the Royal Marsden Hospital United Kingdom National Institute for Health Research Biomedical Research Centre (to Brown G); and the Yorkshire Cancer Research and Pathological Society of Great Britain and Ireland (to West NP).
Conflict-of-interest statement: None to declare.
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. Gina Brown, Consultant Radiologist, Professor, Department of Radiology, Royal Marsden Hospital, Downs Rd, Sutton SM2 5PT, United Kingdom.
Telephone: +44-208-6613156 Fax: +44-208-6439414
Received: March 23, 2016
Peer-review started: March 23, 2016
First decision: May 12, 2016
Revised: July 4, 2016
Accepted: July 31, 2016
Article in press: August 1, 2016
Published online: October 7, 2016
Core Tip

Core tip: The degree of primary tumour regression following neo-adjuvant therapy identified on final histopathological specimens is a prognostic factor and response variation has allowed risk stratification, aiding in post-surgical treatment and follow-up decisions. To do this effectively, we need to have a common language for defining good and poor response. Definitions of response using histopathology scales are heterogenous with 19 different scales. There is one pre-operative magnetic resonance imaging (MRI) scale. Outcomes of recurrence and survival histopathology regression assessments should use Mandard 1, 2/Dworak 3, 4 for good response and Mandard 3, 4, 5/Dworak 0, 1, 2 for poor response. MRI indicates good and poor response by mrTRG1-3 and mrTRG4-5, respectively.