Imaging characterization of renal clear cell carcinoma Poster No.: C-0327 Congress: ECR 2011 Type: Educational Exhibit Authors: S. Ballester 1, A. Gaser 2, M. Dotta 1, M. F. CAPPA 1, F. Hammar 1 ; 1 2 Buenos Aires/AR, C1113AAE/AR Keywords: DOI: Abdomen, Kidney, Oncology, CT, MR, Ultrasound, Comparative studies, Education, Neoplasia 10.1594/ecr2011/C-0327 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. www.myesr.org Page 1 of 9
Learning objectives To identify the imaging characteristics that favor the diagnosis of renal cell clear cells carcinoma (RCC) over a renal mass detected in incidental form. Background The renal carcinoma represents 2 % of adult visceral malignant neoplasms, and 90 % of renal malignant tumors. Eighty percent corresponds to RCC, being the most frecuent subtype. It is three times more common in men, between sixth and seventh decades of life. The classic triad of hematuria, abdominal pain and abdominal palpable mass only occurs in 10% of the cases, generally advanced. It shows multiple forms of presentation, with varied signs and symptoms, such as paraneoplastic syndromes, impregnation syndrome, or simply like an incidental finding in asymptomatic patients (Figure 1). Aproximately half of them are in a stage I or II at diagnosis, but 45% show invasion of the capsule or renal vein, and less frequently secondary lesions in lungs, bones, liver and soft tissue (Figure 2). The prognosis depends directly on the tumor stage, therefore early treatment improves survival. Their treatment is essentially surgical, relegating chemotherapy and alternative treatments for specific cases and / or palliation. The advent of MDCT and the continuous development of MRI allowed to diagnose increasingly smaller lesions and in more precocious stages. However, it is essential to conduct imaging studies with specific renal protocols, thus increasing the sensitivity and specificity of these techniques, and thus, the diagnostic yield. Images for this section: Page 2 of 9
Fig. 1: Asymptomatic 60 year old male patient, who presented a solid nodular lesion in the upper pole of right kidney in ultrasound. CT with intravenous contrast material in their different phases, confirmed this finding, wich can be seen more clearly in nephrographic and excretory phases. Page 3 of 9
Fig. 2: RCC in the left kidney of a 62 year old male patient; it was a stage III lesion, showing direct invasion by contiguity of ipsilateral psoas muscle and adjacent soft tissues. Page 4 of 9
Imaging findings OR Procedure details Tomographic study for renal masses evaluation should include the three corticomedullary, nephrographic and excretion phases (Figure 1), because the heterogeneity in their composition make the lesions more clearly manifested in a particular phase when compared with another. Within the available literature, there are several works that were proposed to analyze differentials tomographic features of renal tumors, arguing that the presence of neovascularization, or calcifications, has a slight association with increased malignancy of the lesion, although their presence and pattern are not predictive of the degree of malignancy of the disease, and that the smooth contours are seen in less aggressive tumors. However, it is now accepted that the most important feature for recognition and high reliability to predict the diagnosis of renal tumor subtype, is the degree and pattern of behavior after intravenous contrast administration. Renal tumors subtypes show different behaviors and patterns of enhancement depending on their type of vascularization and other features. The clear cell carcinoma typically presents as a morphologically heterogeneous mass (Figure 2) and may contain areas of hemorrhage, necrosis, calcification and cystic spaces. These lesions are hypervascularized with intravenous contrast studies (CT, RMI), which showed marked and predominantly peripheral enhancement after its administration (Figure 3), with central hypodense areas represented by areas of necrosis or cystic changes. In MRI studies, they are hypo-isointense on T1 weighted images and iso-hyperintense on T2 weighted images. In in-phase and opposed phase sequences may show signal drop if they have fat content. In ultrasound studies they are nonspecific, showing hyper, iso or hypoechogenicity in comparison to normal renal parenchyma. Images for this section: Page 5 of 9
Fig. 1: CT of the abdomen of a 56 year old male patient with RCC in the right kidney. Note the appearance of the lesion in different phases of the dynamic scan, being more evident in nephrographic phase and difficult to identify in other phases when analyzed individually. Page 6 of 9
Fig. 2: CT of the abdomen with intravenous contrast material showing a large RCC in the left kidney. However, there is no evidence of compromise of adjacent structures. Note the heterogeneous enhancement of the lesion demonstrated on post-contrast phases. Page 7 of 9
Fig. 3: CT of the abdomen with intravenous contrast material of a 53 year old man who had abdominal pain and hematuria. There is a solid mass at the left kidney, which eventually corresponded to an RCC. Note the predominantly peripheral enhancement of the lesion. Page 8 of 9
Conclusion Because of its frequency and malignancy, RCC is one of the most important variants. The main characteristics to predict their diagnosis in imaging studies, and for differential diagnosis with a high degree of reproducibility between different subtypes of renal tumors, are the behavior and pattern of enhancement of these lesions after administration of intravenous contrast material, which in RCC is considerable and varied. The continuous advance of imaging studies has allowed the early detection of renal tumor lesions. It is very important to know the characteristics of this tumor to achieve a specific diagnosis allowing the proper therapeutic approach. Personal Information References Computed Body Tomography with MRI Correlation; Lee-Sagel-Stanley- Heiken, 4th edition, 2006; Basis of TAC Body ; Webb-Brant-Major, 2007 edition; Solid Renal Cortical Tumors: Differentiation with CT. Radiology August 2007 244:494-504; Renal Cell Carcinoma: Unusual Imaging Manifestations. Radiographics January-February 2006 26:233-244; Current Concepts in the Diagnosis and Management of Renal Cell Carcinoma: Role of Multidetector CT and Three-dimensional CT. Radiographics October 2001 21:S237-S254; Common and Uncommon Histologic Subtypes of Renal Cell Carcinoma: Imaging Spectrum with Pathologic Correlation. Radiographics November- December 2006 26:1795-1806. Page 9 of 9