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Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Radiol. Oct 28, 2015; 7(10): 319-328
Published online Oct 28, 2015. doi: 10.4329/wjr.v7.i10.319
Diffusion-weighted imaging of pancreatic cancer
Riccardo De Robertis, Paolo Tinazzi Martini, Emanuele Demozzi, Flavia Dal Corso, Claudio Bassi, Paolo Pederzoli, Mirko D’Onofrio
Riccardo De Robertis, Paolo Tinazzi Martini, Department of Radiology, Casa di Cura Pederzoli, 37019 Peschiera del Garda, Italy
Emanuele Demozzi, Flavia Dal Corso, Mirko D'Onofrio, Verona Comprehensive Cancer Network, Department of Radiology, G.B. Rossi Hospital - University of Verona, 37134 Verona, Italy
Claudio Bassi, Verona Comprehensive Cancer Network - Department of Pancreatic Surgery, G.B. Rossi Hospital - University of Verona, 37134 Verona, Italy
Paolo Pederzoli, Department of Pancreatic Surgery, Casa di Cura Pederzoli, 37019 Peschiera del Garda, Italy
Author contributions: All authors contributed equally to this work; Tinazzi Martini P, Bassi C, Pederzoli P and D’Onofrio M designed the research; Demozzi E and Dal Corso F performed the research and analyzed the data; De Robertis R, Demozzi E and Dal Corso F wrote the paper.
Informed consent statement: The authors declare no potential conflicts of interest for this paper.
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/
Correspondence to: Riccardo De Robertis, MD, Department of Radiology, Casa di Cura Pederzoli, via Monte Baldo 24, 37019 Peschiera del Garda, Italy. riccardo.derobertis@hotmail.it
Telephone: +39-45-8124301 Fax: +39-45-8027490
Received: January 28, 2015
Peer-review started: January 28, 2015
First decision: April 14, 2015
Revised: April 27, 2015
Accepted: August 25, 2015
Article in press: August 28, 2015
Published online: October 28, 2015
Abstract

Magnetic resonance imaging (MRI) is a reliable and accurate imaging method for the evaluation of patients with pancreatic ductal adenocarcinoma (PDAC). Diffusion-weighted imaging (DWI) is a relatively recent technological improvement that expanded MRI capabilities, having brought functional aspects into conventional morphologic MRI evaluation. DWI can depict the random diffusion of water molecules within tissues (the so-called Brownian motions). Modifications of water diffusion induced by different factors acting on the extracellular and intracellular spaces, as increased cell density, edema, fibrosis, or altered functionality of cell membranes, can be detected using this MR sequence. The intravoxel incoherent motion (IVIM) model is an advanced DWI technique that consent a separate quantitative evaluation of all the microscopic random motions that contribute to DWI, which are essentially represented by molecular diffusion and blood microcirculation (perfusion). Technological improvements have made possible the routine use of DWI during abdominal MRI study. Several authors have reported that the addition of DWI sequence can be of value for the evaluation of patients with PDAC, especially improving the staging; nevertheless, it is still unclear whether and how DWI could be helpful for identification, characterization, prognostic stratification and follow-up during treatment. The aim of this paper is to review up-to-date literature data regarding the applications of DWI and IVIM to PDACs.

Keywords: Pancreas, Pancreatic neoplasms, Pancreatic ductal carcinoma, Magnetic resonance imaging, Diffusion magnetic resonance imaging

Core tip: Diffusion-weighted imaging (DWI) plays an important role for the identification of pancreatic adenocarcinoma, even if small in size, thus allowing early diagnosis. The intravoxel incoherent motion model is a promising DWI technique for the characterization of this tumor, with potential usefulness for the differentiation from mass-forming pancreatitis. Thanks to its high negative prognostic value, DWI should be used to assess the presence of liver metastases in patients with pancreatic adenocarcinoma.