Review
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Radiol. May 28, 2016; 8(5): 484-500
Published online May 28, 2016. doi: 10.4329/wjr.v8.i5.484
Review of renal cell carcinoma and its common subtypes in radiology
Gavin Low, Guan Huang, Winnie Fu, Zaahir Moloo, Safwat Girgis
Gavin Low, Guan Huang, Winnie Fu, Department of Radiology and Diagnostic Imaging, University of Alberta Hospital, Edmonton, Alberta T6G 2B7, Canada
Zaahir Moloo, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G 2R3, Canada
Safwat Girgis, Department of Pathology, University of Alberta Hospital, Edmonton, Alberta T6G 2B7, Canada
Author contributions: All authors contributed to the conception and design of the manuscript, acquisition of data, literature review and analysis, critical revision and editing, and approval of the final version.
Conflict-of-interest statement: Authors declare no conflict 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/
Correspondence to: Gavin Low, MBChB, MPhil, MRCS, FRCR, Department of Radiology and Diagnostic Imaging, University of Alberta Hospital, 2A2.41 WMC, 8440-112 Street, Edmonton, Alberta T6G 2B7, Canada. timgy@yahoo.com
Telephone: +1-780-4076907 Fax: +1-780-4073853
Received: August 18, 2015
Peer-review started: August 21, 2015
First decision: January 15, 2016
Revised: January 20, 2016
Accepted: March 7, 2016
Article in press: March 9, 2016
Published online: May 28, 2016
Abstract

Representing 2%-3% of adult cancers, renal cell carcinoma (RCC) accounts for 90% of renal malignancies and is the most lethal neoplasm of the urologic system. Over the last 65 years, the incidence of RCC has increased at a rate of 2% per year. The increased incidence is at least partly due to improved tumor detection secondary to greater availability of high-resolution cross-sectional imaging modalities over the last few decades. Most RCCs are asymptomatic at discovery and are detected as unexpected findings on imaging performed for unrelated clinical indications. The 2004 World Health Organization Classification of adult renal tumors stratifies RCC into several distinct histologic subtypes of which clear cell, papillary and chromophobe tumors account for 70%, 10%-15%, and 5%, respectively. Knowledge of the RCC subtype is important because the various subtypes are associated with different biologic behavior, prognosis and treatment options. Furthermore, the common RCC subtypes can often be discriminated non-invasively based on gross morphologic imaging appearances, signal intensity on T2-weighted magnetic resonance images, and the degree of tumor enhancement on dynamic contrast-enhanced computed tomography or magnetic resonance imaging examinations. In this article, we review the incidence and survival data, risk factors, clinical and biochemical findings, imaging findings, staging, differential diagnosis, management options and post-treatment follow-up of RCC, with attention focused on the common subtypes.

Keywords: Papillary renal cell carcinoma, Multidetector computed tomography, Clear cell renal cell carcinoma, Magnetic resonance imaging, Chromophobe renal cell carcinoma, Tumor staging, Treatment protocols

Core tip: The common renal cell carcinoma (RCC) subtypes can often be discriminated non-invasively based on characteristic imaging appearances. Clear cell RCC typically shows a heterogeneous consistency (secondary to necrosis, cystic change or hemorrhage), has high signal intensity on T2-weighted magnetic resonance imaging (MRI), and is hypervascular on dynamic contrast-enhanced computed tomography or MRI examinations. Most papillary RCCs are detected while at a low grade and small size, show low signal intensity on T2-weighted MRI, and are hypovascular following contrast administration. Chromophobe RCCs may have a homogeneous solid appearance even when large, and may exhibit a central stellate scar and spoke-wheel enhancement.