Gulgun Engin, Rasul Sharifov REVIEW 214 June 10, 2017|Volume 8|Issue 3| WJCO|www.wjgnet.com Magnetic resonance imaging for diagnosis and neoadjuvant treatment evaluation in locally advanced rectal cancer: A pictorial review Gulgun Engin, Oncology Institute, Istanbul University, 34390 Capa, Istanbul, Turkey Rasul Sharifov, Department of Radiology, Faculty of Medicine, Bezmialem Vakif University, 34093 Fatih, Istanbul, Turkey Author contributions: Engin G designed and wrote the paper; Sharifov R performed MRI. Confict-of-interest statement: Authors declare no confict of interests for this article. 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: http://creativecommons.org/ licenses/by-nc/4.0/ Manuscript source: Invited manuscript Correspondence to: Gulgun Engin, MD, Oncology Institute, Istanbul University, Millet Street, 34390 Capa, Istanbul, Turkey. gengin@istanbul.edu.tr Telephone: +90-212-4142000 Fax: +90-212-5348078 Received: January 28, 2017 Peer-review started: February 10, 2017 First decision: March 27, 2017 Revised: May 4, 2017 Accepted: May 18, 2017 Article in press: May 20, 2017 Published online: June 10, 2017 Abstract High-resolution pelvic magnetic resonance imaging (MRI) is the primary method for staging rectal cancer. MRI is highly accurate in the primary staging of rectal cancer; however, it has not proven to be effective in re- staging, especially in complete response evaluation after neoadjuvant therapy. Neoadjuvant chemoradiotherapy produces many changes in rectal tumors and on adjacent area, as a result, local tumor extent may not be accurately determined. However, adding diffusion-weighted se- quences to the standard approach can improve diagnostic accuracy. In this pictorial review, an overview of the situation of MRI in the staging and re-staging of rectal cancer is exhibited as a pictorial assay. An experience- and literature-based discussion of limitations and diffculties in interpretation are also presented. Key words: Rectal cancer; Locally advanced; Magnetic resonance imaging; Staging; Neoadjuvant treatment © The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved. Core tip: Accurate staging and circumferential resection margin evaluation significantly impacts determining op- timal treatment scheme. Preoperative magnetic resonance imaging (MRI) is highly accurate; however, it has yet to be proved as effective in re-staging. The adding of diffusion- weighted sequences to standard T2-weighted MRI can positively affect its diagnostic accuracy. Engin G, Sharifov R. Magnetic resonance imaging for diagnosis and neoadjuvant treatment evaluation in locally advanced rectal cancer: A pictorial review. World J Clin Oncol 2017; 8(3): 214-229 Available from: URL: http://www.wjgnet.com/2218-4333/full/v8/ i3/214.htm DOI: http://dx.doi.org/10.5306/wjco.v8.i3.214 INTRODUCTION Multimodal treatment of rectal cancer, with the combination World Journal of Clinical Oncology W JC O Submit a Manuscript: http://www.f6publishing.com DOI: 10.5306/wjco.v8.i3.214 World J Clin Oncol 2017 June 10; 8(3): 214-229 ISSN 2218-4333 (online)