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Comparative diagnostic performance of contrast-enhanced ultrasound and dynamic contrast-enhanced magnetic resonance imaging for differentiating clear cell and non-clear cell renal cell carcinoma. Eur Radiol 2023; 33:3766-3774. [PMID: 36725722 DOI: 10.1007/s00330-023-09391-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 12/09/2022] [Accepted: 12/23/2022] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To compare the diagnostic efficiency of contrast-enhanced ultrasound (CEUS) with that of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for the differential diagnosis of clear and non-clear cell renal cell carcinoma, as confirmed by subsequent pathology. METHODS A total of 181 patients with 184 renal lesions diagnosed by both CEUS and DCE-MRI were enrolled in the study, including 136 clear cell renal cell carcinoma (ccRCC) and 48 non-clear cell renal cell carcinoma (non-ccRCC) tumors. All lesions were confirmed by histopathologic diagnosis after surgical resection. Interobserver agreement was estimated using a weighted kappa statistic. Diagnostic efficiency in evaluating ccRCC and non-ccRCC was compared between CEUS and DCE-MRI. RESULTS The weighted kappa value for interobserver agreement was 0.746 to 0.884 for CEUS diagnosis and 0.764 to 0.895 for DCE-MRI diagnosis. Good diagnostic performance in differential diagnosis of ccRCC and non-ccRCC was displayed by both CEUS and DCE-MRI: sensitivity was 89.7% and 91.9%, respectively; specificity was 77.1% and 68.8%, respectively; and area under the receiver operating curve was 0.834 and 0.803, respectively. No statistically significant differences were present between the two methods (p = 0.54). CONCLUSIONS Both CEUS and DCE-MRI imaging are effective for the differential diagnosis of ccRCC and non-ccRCC. Thus, CEUS could be an alternative to DCE-MRI as a first test for patients at risk of renal cancer, particularly where DCE-MRI cannot be carried out. KEY POINTS • CEUS and DCE-MRI features can help differentiate ccRCC and non-ccRCC. • The differential diagnosis of ccRCC and non-ccRCC by CEUS is comparable to that of DCE-MRI. • Interobserver agreement is generally high using CEUS and DCE-MRI.
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Prevalence of benign pathology after partial nephrectomy for suspected renal tumor: A systematic review and meta-analysis. Int J Surg 2020; 84:161-170. [PMID: 33220454 DOI: 10.1016/j.ijsu.2020.11.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 08/13/2020] [Accepted: 11/09/2020] [Indexed: 12/31/2022]
Abstract
OBJECTIVE To investigate the overall prevalence of benign pathology after partial nephrectomy (PN) and identify predictive factors for benign pathology after PN. METHODS A systematic review was performed following the PRISMA guidelines. PubMed/Medline, Embase, and the Cochrane Library were searched up to January 2019PRISMA guidelines. The data for the meta-analysis and network meta-analysis were pooled using a random-effects model. RESULTS There were 144 studies included in the final analysis, which was comprised of 79 observational studies (n = 37,300) and 65 comparative studies (n = 18,552). The overall prevalence rate of benign pathology after PN was 0.19 (95% CI: 0.18-0.21). According to the procedure types, the prevalence rate of benign pathology was 0.17 (95% CI: 0.15-0.19), 0.24 (95% CI: 0.22-0.27), and 0.16 (95% CI: 0.15-0.18) in open partial nephrectomy, laparoscopic partial nephrectomy, and robot-assisted laparoscopic partial nephrectomy, respectively. The significant moderating factors were gender, publication year, the origin of the study, and procedure types. The three most common benign pathology types were oncocytomas, angiomyolipomas, and renal cysts (44.50%, 30.20%, and 10.99%, respectively). CONCLUSIONS The overall prevalence of benign pathology after PN was not low and it was affected by female gender, studies published before 2010, studies originating from Western areas, and laparoscopic procedure types.
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Yaşar S, Voyvoda N, Voyvoda B, Özer T. Using texture analysis as a predictive factor of subtype, grade and stage of renal cell carcinoma. Abdom Radiol (NY) 2020; 45:3821-3830. [PMID: 32253464 DOI: 10.1007/s00261-020-02495-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
OBJECTIVE The aim of this study was to evaluate the correlation between the tissue texture analysis and the histological subtypes, grade and stage of the disease in patients with renal cell carcinoma (RCC). MATERIALS AND METHODS Seventy-seven patients who underwent computed tomography due to renal mass and diagnosed with RCC as a result of pathological examination were retrospectively analyzed. In these analyses, the demographic characteristics, pathological and radiological findings of the patients were evaluated. The masses were introduced to the Radiomics extension of the software and the first- and second-order texture analysis parameters were obtained. The correlation of these parameters with histological subtype, Fuhrman grade and TNM stage was investigated. RESULTS In the comparison of the Radiomics values by stages, "minimum", "Long Run Low Gray-level Emphasis" values were higher in the stage 1-2 group, while "Energy", "Total energy", "Range", "Joint Average", "Sum Average", "Gray-Level Non-Uniformity", "Short-Run High Gray-level Emphasis ", "Run Length Non-Uniformity "and "High Gray-Level Run Emphasis "values were higher in the stage 3-4 group. Of these parameters, only "Gray-Level Non-Uniformity" and "Run Length Non-Uniformity'' values were significantly lower in tumors with low Fuhrman grade (1-2) and low TNM stage (1-2). There was no statistically significant correlation between the parameters found to be significant in histological subtype differentiation and Fuhrman grade and TNM stage. CONCLUSION This study demonstrates that "Gray-Level Non-Uniformity" and "Run Length Non-Uniformity "parameters in the texture analysis method can be used to evaluate the prognosis in patients with RCC.
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Affiliation(s)
- Servan Yaşar
- Department of Radiology, Kocaeli Derince Training and Research Hospital, University of Health Sciences, İbni Sina M. Sopalı Mevki Lojman S. Derince, Kocaeli, Turkey
| | - Nuray Voyvoda
- Department of Radiology, Kocaeli Derince Training and Research Hospital, University of Health Sciences, İbni Sina M. Sopalı Mevki Lojman S. Derince, Kocaeli, Turkey.
| | - Bekir Voyvoda
- Department of Urology, Kocaeli Derince Training and Research Hospital, University of Health Sciences, Kocaeli, Turkey
| | - Tülay Özer
- Department of Radiology, Kocaeli Derince Training and Research Hospital, University of Health Sciences, İbni Sina M. Sopalı Mevki Lojman S. Derince, Kocaeli, Turkey
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Kim JH, Li S, Khandwala Y, Chung KJ, Park HK, Chung BI. Association of Prevalence of Benign Pathologic Findings After Partial Nephrectomy With Preoperative Imaging Patterns in the United States From 2007 to 2014. JAMA Surg 2019; 154:225-231. [PMID: 30516801 DOI: 10.1001/jamasurg.2018.4602] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Importance Although the intent of nephron-sparing surgery is to eradicate malignant tumors found on preoperative imaging, benign masses often cannot be differentiated from malignant tumors. However, in the past there have been discrepancies in the reported percentages of benign masses removed by partial nephrectomy (PNx). Objective To investigate the annual trend of prevalence of benign pathologic findings after PNx and to investigate what potential factors are associated with this prevalence. Design, Setting, and Participants A total of 18 060 patients who underwent PNx between 2007 and 2014 were selected from Truven Health MarketScan Research Databases. We selected those patients who underwent PNx as an inpatient from 2007 and set the surgery date as the index date. Overall, a total of 21 445 patients with International Classification of Diseases, Ninth Revision, Clinical Modification code of 55.4 were identified from 2007 to 2015. Main Outcomes and Measures The annual trend of benign pathologic findings was described as an actual number and as a proportion. Univariate and multiple analyses were performed to investigate factors predictive of a benign final pathologic diagnosis, including type of preoperative imaging modality or performance of a renal mass biopsy. Results Among the 18 060 patients, mean (SD) age was 57 (12) years, and there were 10637 (58.9%) men and 7423 (41.1%) women. The overall prevalence of benign pathologic findings was 30.9% and the annual trends demonstrated a prevalence of over 30% for nearly every year of the study period. On univariate analysis, the performance of magnetic resonance imaging (MRI) and renal mass biopsy was associated with benign pathologic findings (P = .02 and P < .001, respectively). On multivariable analysis, female sex (odds ratio [OR], 0.62; 95% CI, 0.58-0.66; P < .001), older age (>65 years) (OR, 0.99; 95% CI, 0.99-0.99; P < .001), and computed tomography (CT) only preoperative imaging (OR, 1.16; 95% CI, 1.05-1.28; P = .004) were associated with benign pathologic findings after PNx. Conclusions and Relevance We found that the overall prevalence of benign pathologic findings after PNx was higher than the literature suggests, with consistent year-over-year rates exceeding 30%. Female sex, older age (>65 years), and CT only preoperative imaging were predictive of a benign tumor. Further elucidation concerning covariates associated with a benign diagnosis should be the focus of future investigations to identify a cohort of patients who could potentially avoid unnecessary surgical intervention.
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Affiliation(s)
- Jae Heon Kim
- Department of Urology, Stanford University Medical Center, Stanford, California.,Department of Urology, Soonchunhyang University Hospital, Soonchuhyang University Medical College, Seoul, Korea
| | - Shufeng Li
- Department of Urology and Dermatology, Stanford University Medical Center, Stanford, California
| | - Yash Khandwala
- Department of Urology, Stanford University Medical Center, Stanford, California.,San Diego School of Medicine, University of California, San Diego
| | - Kyung Jin Chung
- Department of Urology, Stanford University Medical Center, Stanford, California
| | - Hyung Keun Park
- Department of Urology, Stanford University Medical Center, Stanford, California
| | - Benjamin I Chung
- Department of Urology, Stanford University Medical Center, Stanford, California
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Ziegelmüller BK, Spek A, Szabados B, Casuscelli J, Clevert DA, Staehler M. [Epidemiology and diagnostic assessment of small renal masses]. Urologe A 2019; 57:274-279. [PMID: 29460170 DOI: 10.1007/s00120-018-0585-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
BACKGROUND The incidence of small renal masses has been rising over the last few decades. At the same time, mortality of renal cell carcinoma (RCC) is decreasing. These trends can be explained by the availability of improved therapeutic measures and the good prognosis of small renal masses (SRM) turning out to be histopathologically benign or of low malignancy in many cases. OBJECTIVES The aim of this article is to present epidemiology and diagnostic assessment of SRM. MATERIALS AND METHODS Statistics, basic research, guidelines. RESULTS The incidence of SRM is rising due to the widespread use of imaging techniques such as computed tomography (CT), magnetic resonance imaging (MRI), and contrast-enhanced ultrasound (CEUS). Sensitivity is excellent for CEUS and for CECT in the characterization of SRM, while good specificity values can be reached by MRI. For characterization of complex cystic renal masses, CEUS has good diagnostic accuracy. CONCLUSIONS Due to improved diagnostic possibilities, SRMs can be diagnosed in early asymptomatic stages. As SRM have a good prognosis and often are of low malignancy therapy, options should be carefully considered; especially in older patients, active surveillance should considered.
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Affiliation(s)
- B K Ziegelmüller
- Urologische Klinik und Poliklinik, Klinikum der Ludwig-Maximilians-Universität München, Marchioninistr. 15, 81377, München, Deutschland.
| | - A Spek
- Urologische Klinik und Poliklinik, Klinikum der Ludwig-Maximilians-Universität München, Marchioninistr. 15, 81377, München, Deutschland
| | - B Szabados
- Urologische Klinik und Poliklinik, Klinikum der Ludwig-Maximilians-Universität München, Marchioninistr. 15, 81377, München, Deutschland
| | - J Casuscelli
- Urologische Klinik und Poliklinik, Klinikum der Ludwig-Maximilians-Universität München, Marchioninistr. 15, 81377, München, Deutschland
| | - D-A Clevert
- Urologische Klinik und Poliklinik, Klinikum der Ludwig-Maximilians-Universität München, Marchioninistr. 15, 81377, München, Deutschland
| | - M Staehler
- Urologische Klinik und Poliklinik, Klinikum der Ludwig-Maximilians-Universität München, Marchioninistr. 15, 81377, München, Deutschland
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Vogel C, Ziegelmüller B, Ljungberg B, Bensalah K, Bex A, Canfield S, Giles RH, Hora M, Kuczyk MA, Merseburger AS, Powles T, Albiges L, Stewart F, Volpe A, Graser A, Schlemmer M, Yuan C, Lam T, Staehler M. Imaging in Suspected Renal-Cell Carcinoma: Systematic Review. Clin Genitourin Cancer 2019; 17:e345-e355. [DOI: 10.1016/j.clgc.2018.07.024] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 07/08/2018] [Accepted: 07/30/2018] [Indexed: 01/14/2023]
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Kim JH, Li S, Khandwala Y, Del Giudice F, Chung KJ, Park HK, Chung BI. National trends of preoperative imaging modalities before partial nephrectomy for renal masses in the U.S. from 2007-2015. Can Urol Assoc J 2019; 13:E89-E94. [PMID: 30169151 DOI: 10.5489/cuaj.5414] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Although the performance of partial nephrectomies (PN) for renal masses has increased rapidly over the years, only a few studies have investigated the frequency and patterns of preoperative imaging modalities. The aim of this study was to investigate the frequency and patterns in preoperative imaging modalities before PN. METHODS A total of 21 445 patients who underwent PN between 2007 and 2015 were selected from a national representative population in the MarketScan database and included in this study. The annual incidence and proportion of PN, as well as the use of each preoperative imaging modality were analyzed. RESULTS Both annual crude number and frequency rate of PN decreased or became static since 2012. Computed tomography (CT) shows the greatest proportion of the crude number and percentage; despite a slight decrease in percentage, it is still >80%. Among the combinations, CT alone and CT combined with ultrasonography showed the highest performance rate during the complete observational period. The proportion of all other combinations, which include other complex combinations except CT alone, CT plus ultrasonography, CT plus magnetic resonance imaging (MRI), and CT plus MRI plus ultrasonography, was 13.95% in 2007, but increased to 19.04% in 2014. CONCLUSIONS CT still plays a major role in preoperative imaging for renal masses, whereby CT alone and CT combined with ultrasonography account for a major proportion of the preoperative imaging patterns. The use of other imaging combinations, as well as renal biopsies, shows an increasing trend. Additional studies are needed to investigate whether this trend in preoperative imaging is related to the frequency rate of PN.
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Affiliation(s)
- Jae Heon Kim
- Department of Urology, Stanford University Medical Center, Stanford, CA, United States.,Department of Urology, Soonchunhyang University Hospital, Soonchuhyang University Medical College, Seoul, Korea
| | - Shufeng Li
- Department of Urology and Dermatology, Stanford University Medical Center, CA, United States
| | - Yash Khandwala
- Department of Urology, Stanford University Medical Center, Stanford, CA, United States.,University of California, San Diego School of Medicine, San Diego, CA, United States
| | | | - Kyung Jin Chung
- Department of Urology, Stanford University Medical Center, Stanford, CA, United States
| | - Hyung Keun Park
- Department of Urology, Stanford University Medical Center, Stanford, CA, United States
| | - Benjamin I Chung
- Department of Urology, Stanford University Medical Center, Stanford, CA, United States
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Wang HY, Su ZH, Xu X, Huang N, Sun ZP, Wang YW, Li L, Guo AT, Chen X, Ma X, Ma L, Ye HY. Dynamic Contrast-enhanced MRI in Renal Tumors: Common Subtype Differentiation using Pharmacokinetics. Sci Rep 2017; 7:3117. [PMID: 28596583 PMCID: PMC5465189 DOI: 10.1038/s41598-017-03376-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 04/27/2017] [Indexed: 01/14/2023] Open
Abstract
Preoperative renal tumor subtype differentiation is important for radiology and urology in clinical practice. Pharmacokinetic data (Ktrans & Ve, etc.) derived from dynamic contrast-enhanced MRI (DCE-MRI) have been used to investigate tumor vessel permeability. In this prospective study on DCE-MRI pharmacokinetic studies, we enrolled patients with five common renal tumor subtypes: clear cell renal cell carcinoma (ccRCC; n = 65), papillary renal cell carcinoma (pRCC; n = 12), chromophobic renal cell carcinoma (cRCC; n = 9), uroepithelial carcinoma (UEC; n = 14), and fat-poor angiomyolipoma (fpAML; n = 10). The results show that Ktrans of ccRCC, pRCC, cRCC, UEC and fpAML (0.459 ± 0.190 min−1, 0.206 ± 0.127 min−1, 0.311 ± 0.111 min−1, 0.235 ± 0.116 min−1, 0.511 ± 0.159 min−1, respectively) were different, but Ve was not. Ktrans could distinguish ccRCC from non-ccRCC (pRCC & cRCC) with a sensitivity of 76.9% and a specificity of 71.4%, respectively, as well as to differentiate fpAML from non-ccRCC with a sensitivity of 100% and a specificity of 76.2%, respectively. Our findings suggest that DCE-MRI pharmacokinetics are promising for differential diagnosis of renal tumors, especially for RCC subtype characterization and differentiation between fpAML and non-ccRCC, which may facilitate the treatment of renal tumors.
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Affiliation(s)
- Hai-Yi Wang
- Department of Radiology, Chinese PLA General Hospital, No.28 Fuxing Road, Haidian District, Beijing, 100853, China
| | - Zi-Hua Su
- Beijing Aerospace Changfeng Co. Ltd., No. 51-A Yongding Road, Haidian District, Beijing, 100854, China
| | - Xiao Xu
- Lift Science, Advanced Application Team, GE Healthcare China, Shanghai, 201203, China
| | - Ning Huang
- Lift Science, Advanced Application Team, GE Healthcare China, Beijing, 100176, China
| | - Zhi-Peng Sun
- Department of Radiology, No.1 Hospital of Zhangjiakou, Zhangjiakou, 075000, Hebei Province, China
| | - Ying-Wei Wang
- Department of Radiology, Chinese PLA General Hospital, No.28 Fuxing Road, Haidian District, Beijing, 100853, China
| | - Lu Li
- Department of Radiology, Chinese PLA General Hospital, No.28 Fuxing Road, Haidian District, Beijing, 100853, China
| | - Ai-Tao Guo
- Department of Pathology, PLA General Hospital, Beijing, China, No. 28 Fuxing Road, Haidian District, Beijing, 100853, China
| | - Xin Chen
- Department of Pathology, PLA General Hospital, Beijing, China, No. 28 Fuxing Road, Haidian District, Beijing, 100853, China
| | - Xin Ma
- Department of Urology, PLA General Hospital, Beijing, China, No. 28 Fuxing Road, Haidian District, Beijing, 100853, China
| | - Lin Ma
- Department of Radiology, Chinese PLA General Hospital, No.28 Fuxing Road, Haidian District, Beijing, 100853, China
| | - Hui-Yi Ye
- Department of Radiology, Chinese PLA General Hospital, No.28 Fuxing Road, Haidian District, Beijing, 100853, China.
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Tzortzakakis A, Gustafsson O, Karlsson M, Ekström-Ehn L, Ghaffarpour R, Axelsson R. Visual evaluation and differentiation of renal oncocytomas from renal cell carcinomas by means of 99mTc-sestamibi SPECT/CT. EJNMMI Res 2017; 7:29. [PMID: 28357787 PMCID: PMC5371538 DOI: 10.1186/s13550-017-0278-z] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 03/15/2017] [Indexed: 12/28/2022] Open
Abstract
Background Despite the progress in the quality of multiphasic CT and MRI scans, it is still difficult to fully characterize a solid kidney lesion. Approximately 10% of all solid renal tumours turn out to be oncocytomas. In actual clinical practice, this is verified only following unnecessary surgery or a renal biopsy/ablation. The objective of our pilot study examines whether 99mTc-sestamibi SPECT/CT can play a crucial role in the characterization of solid renal neoplasms and the differentiation of oncocytomas from renal cell carcinomas. The study included 27 patients identified with 31 solid renal lesions. All patients were discussed in a multidisciplinary conference, and a decision for surgery or biopsy was taken. Prior to invasive procedures, patients underwent a SPECT/CT with 99mTc-sestamibi. Visual evaluation was performed, and any focal 99mTc-sestamibi uptake detected on SPECT in the localisation of tumour was considered as positive. Results Eleven out of 12 oncocytomas (91.6%) displayed positive uptake of 99mTc-sestamibi. Three hybrid tumours (mixed-type oncocytoma and chromophobe renal cancer) were positive on SPECT/CT. One papillary renal cell carcinoma had a slight uptake of 99mTc-sestamibi. The remaining 11 renal cell carcinomas were sestamibi negative. Conclusions Differentiation of benign renal oncocytomas from renal cell carcinomas seems very promising on 99mTc-sestamibi SPECT/CT examination. Additional supplement to visual evaluation, i.e. quantitative tools, should be sought for an accurate estimate of biological behaviour and hence a secure diagnosis.
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Affiliation(s)
- Antonios Tzortzakakis
- Radiology Department, Division of Medical Imaging and Technology, Karolinska University Hospital, C1-46, SE-141 86, Huddinge, Stockholm, Sweden.
| | - Ove Gustafsson
- Division of Urology, Karolinska University Hospital, Huddinge, Sweden.,Division of Radiology, Department for Clinical Science Intervention and Technology (CLINTEC), Karolinska Institute and Medical Physics and Nuclear Medicine, BOF Karolinska University Hospital, Huddinge, Sweden
| | - Mattias Karlsson
- Medical Radiation Physics and Nuclear Medicine, Functional Unit of Nuclear Medicine, Karolinska University Hospital, Huddinge, Sweden
| | | | | | - Rimma Axelsson
- Division of Radiology, Department for Clinical Science Intervention and Technology (CLINTEC), Karolinska Institute and Medical Physics and Nuclear Medicine, BOF Karolinska University Hospital, Huddinge, Sweden.,Medical Radiation Physics and Nuclear Medicine, Imaging and Physiology, Karolinska University Hospital, Huddinge, Sweden
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10
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Xue LY, Lu Q, Huang BJ, Li CX, Yan LX, Wang WP. Differentiation of subtypes of renal cell carcinoma with contrast-enhanced ultrasonography. Clin Hemorheol Microcirc 2017; 63:361-371. [PMID: 26598999 DOI: 10.3233/ch-152024] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
We aimed to assess the difference of enhancement patterns among the three RCC subtypes with contrast-enhanced ultrasound (CEUS). Two hundreds cases of pathologically proved clear cell renal cell carcinomas (ccRCC), 58 papillary renal cell carcinomas (pRCC) and 51 chromophobe renal cell carcinomas (chRCC) underwent preoperative conventional ultrasound and CEUS. The wash-in and wash-out pattern, peak enhancement degree and homogeneity, and the presence of pseudocapsule were evaluated by two blinded observers respectively. The interreader agreement in the characterization of CEUS features between two observers was good (κ = 0.649-0.775). Compared with pRCCs and chRCCs, ccRCCs demonstrated higher frequency of simultaneous wash-in pattern, hyperenhancement and heterogeneity with necrotic areas. Most pRCCs and chRCCs manifested hypoenhancement, homogeneity, fast wash-out and presence of pseudocapsule. The only difference we obtained between pRCC and chRCC was the wash-in pattern, with slow wash-in in pRCC and simultaneous wash-in in chRCC. In small lesions with long diameter≤3 cm, the majority of the three subtypes of RCC showed homogeneous enhancement and there was no difference among them. CEUS was a useful method to preoperatively differentiate the ccRCC from non-ccRCC subtypes. There were no distinguishing features identifid on CEUS that allowed reliable differentiation of pRCC from chRCC.
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Affiliation(s)
- Li-Yun Xue
- Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai, China.,Shanghai Institute of Medical Imaging, Shanghai, China
| | - Qing Lu
- Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai, China.,Shanghai Institute of Medical Imaging, Shanghai, China
| | - Bei-Jian Huang
- Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai, China.,Shanghai Institute of Medical Imaging, Shanghai, China
| | - Cui-Xian Li
- Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai, China.,Shanghai Institute of Medical Imaging, Shanghai, China
| | - Li-Xia Yan
- Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai, China.,Shanghai Institute of Medical Imaging, Shanghai, China
| | - Wen-Ping Wang
- Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai, China.,Shanghai Institute of Medical Imaging, Shanghai, China
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Differentiation of Clear Cell Renal Cell Carcinoma From Other Renal Cortical Tumors by Use of a Quantitative Multiparametric MRI Approach. AJR Am J Roentgenol 2017; 208:W85-W91. [PMID: 28095036 DOI: 10.2214/ajr.16.16652] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
OBJECTIVE The purpose of this study was to develop a quantitative multiparametric MRI approach to differentiating clear cell renal cell carcinoma (RCC) from other renal cortical tumors. MATERIALS AND METHODS This retrospective study included 119 patients with 124 histopathologically confirmed renal cortical tumors who underwent preoperative MRI including DWI, contrast-enhanced, and chemical-shift sequences before nephrectomy. Two radiologists independently assessed each tumor volumetrically, and apparent diffusion coefficient values, parameters from multiphasic contrast-enhanced MRI (peak enhancement, upslope, downslope, AUC), and chemical-shift indexes were calculated. Univariate and multivariable logistic regression analyses were performed to identify parameters associated with clear cell RCC. RESULTS Interreader agreement was excellent (intraclass correlation coefficient, 0.815-0.994). The parameters apparent diffusion coefficient (reader 1 AUC, 0.804; reader 2, 0.807), peak enhancement (reader 1 AUC, 0.629; reader 2, 0.606), and downslope (reader 1 AUC, 0.575; reader 2, 0.561) were significantly associated with discriminating clear cell RCC from other renal cortical tumors. The combination of all three parameters further increased diagnostic accuracy (reader 1 AUC, 0.889; reader 2, 0.907; both p ≤ 0.001), yielding sensitivities of 0.897 for reader 1 and 0.897 for reader 2, and specificities of 0.762 for reader 1 and 0.738 for reader 2 in the identification of clear cell RCC. With maximized sensitivity, specificities of 0.429 and 0.262 were reached for readers 1 and 2, respectively. CONCLUSION A quantitative multiparametric approach statistically significantly improves diagnostic performance in differentiating clear cell RCC from other renal cortical tumors.
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12
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Diagnostic accuracy of contrast-enhanced computed tomography and contrast-enhanced magnetic resonance imaging of small renal masses in real practice: sensitivity and specificity according to subjective radiologic interpretation. World J Surg Oncol 2016; 14:260. [PMID: 27729042 PMCID: PMC5059933 DOI: 10.1186/s12957-016-1017-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 10/04/2016] [Indexed: 12/26/2022] Open
Abstract
Background The aim of this study was to investigate the diagnostic accuracy of contrast-enhanced computed tomography (CT) and contrast-enhanced magnetic resonance imaging (MRI) of small renal masses in real practice. Methods Contrast-enhanced CT and MRI were performed between February 2008 and February 2013 on 68 patients who had suspected small (≤4 cm) renal cell carcinoma (RCC) based on ultrasonographic measurements. CT and MRI radiographs were reviewed, and the findings of small renal masses were re-categorized into five dichotomized scales by the same two radiologists who had interpreted the original images. Receiver operating characteristics curve analysis was performed, and sensitivity and specificity were determined. Results Among the 68 patients, 60 (88.2 %) had RCC and eight had benign disease. The diagnostic accuracy rates of contrast-enhanced CT and MRI were 79.41 and 88.23 %, respectively. Diagnostic accuracy was greater when using contrast-enhanced MRI because too many masses (67.6 %) were characterized as “4 (probably solid cancer) or 5 (definitely solid cancer).” The sensitivity of contrast-enhanced CT and MRI for predicting RCC were 79.7 and 88.1 %, respectively. The specificities of contrast-enhanced CT and MRI for predicting RCC were 44.4 and 33.3 %, respectively. Fourteen diagnoses (20.5 %) were missed or inconsistent compared with the final pathological diagnoses. One appropriate nephroureterectomy and five unnecessary percutaneous biopsies were performed for RCC. Seven unnecessary partial nephrectomies were performed for benign disease. Conclusions Although contrast-enhanced CT and MRI showed high sensitivity for detecting small renal masses, specificity remained low.
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Quantitative evaluation of contrast-enhanced ultrasound for differentiation of renal cell carcinoma subtypes and angiomyolipoma. Eur J Radiol 2016; 85:795-802. [PMID: 26971426 DOI: 10.1016/j.ejrad.2016.01.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 01/05/2016] [Accepted: 01/16/2016] [Indexed: 12/18/2022]
Abstract
PURPOSE To investigate the value of quantitative parameters of contrast-enhanced ultrasound (CEUS) in the differentiation of subtypes of renal cell carcinoma (RCC) and angiomyolipoma (AML). METHODS The quantitative characteristics of 341 RCCs and 88 AMLs were analyzed with quantitative software (SonoLiver). Quantitative analysis was conducted in the whole tumor (ROItumor) and the maximum enhanced area of the tumor (ROImax), acquiring the parameters of maximum intensity (IMAX), rise time (RT), time to peak (TTP), mean transit time (mTT), and area under the curve (AUC), were derived and analyzed. The difference values between ROImax and normal renal cortex (ΔPar.s, including ΔIMAX, ΔRT, ΔTTP, ΔmTT, ΔAUC) were compared among renal histotypes. RESULTS All time-related parameters (including RT, TTP and mTT) of ROImax were shorter than the corresponding parameters of ROItumor in RCC subtypes (all p<0.05), but made no statistical difference in AMLs (all p>0.05). There were significant differences of all ΔPar.s among RCC subtypes and AML (all p<0.01). ΔIMAX and ΔAUC showed the trend that ccRCC>AML>pRCC=chRCC. ΔTTP showed AML=pRCC=chRCC>ccRCC, ΔRT and ΔmTT showed AML>pRCC=chRCC=ccRCC. ΔmTT could distinguish RCC from AML with the area under the ROC curve (AUC) of 0.86. The AUC of ΔIMAX and ΔAUC was 0.89 and 0.92 vs 0.85 and 0.85 for discriminating between pRCC (or chRCC) and AML vs ccRCC and AML. CONCLUSIONS Quantitative analysis of CEUS is a useful modality in AML and RCC subtypes' differentiation, by using ΔmTT, ΔIMAX and ΔAUC.
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Abstract
This article illustrates the imaging characteristics of cystic and solid renal masses, along with a summary of identified imaging criteria that may be of use to differentiate masses that are more likely to be benign from those that are more likely to be malignant. In addition, important features of known or suspected renal cancers that should be identified before treatment are summarized, including staging of renal cancer and RENAL nephrometry. Finally, the imaging appearance of patients following treatment of renal cancer, including after partial or total nephrectomy, thermal ablation, or chemotherapy for metastatic disease, is reviewed.
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Affiliation(s)
- Richard H Cohan
- Department of Radiology, University of Michigan Hospital, University of Michigan Health System, Room B1-D502, 1500 East Medical Center Drive, Ann Arbor, MI 48109-5030, USA.
| | - James H Ellis
- Department of Radiology, University of Michigan Hospital, University of Michigan Health System, Room B1-D502, 1500 East Medical Center Drive, Ann Arbor, MI 48109-5030, USA
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Zhang HM, Wu YH, Gan Q, Lyu X, Zhu XL, Kuang M, Liu RB, Huang ZX, Yuan F, Liu XJ, Song B. Diagnostic Utility of Diffusion-weighted Magnetic Resonance Imaging in Differentiating Small Solid Renal Tumors (≤ 4 cm) at 3.0T Magnetic Resonance Imaging. Chin Med J (Engl) 2015; 128:1444-9. [PMID: 26021498 PMCID: PMC4733766 DOI: 10.4103/0366-6999.157648] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND The aim of this study was to assess the performance of apparent diffusion coefficient (ADC) measurement obtained with diffusion-weighted magnetic resonance imaging (DW-MRI) to distinguish renal cell carcinomas (RCCs) from small benign solid renal tumors (≤ 4 cm). METHODS In this cross-sectional study, 49 consecutive patients with histopathologically confirmed small solid renal tumors, and seven healthy volunteers were imaged using nonenhanced MRI and DW-MRI. The ADC map was calculated using the b values of 0, 50, 400, and 600 s/mm 2 and values compared via the Kruskal-Wallis and Mann-Whitney tests. The utility of ADC for differentiating RCCs and benign lesions was assessed using a receiver operating characteristic curve. Multiple nonenhanced MRI features were analyzed by Logistic regression. RESULTS The tumors consisted of 33 cases of clear-cell RCCs (ccRCCs) and 16 cases of benign tumors, including 14 cases of minimal fat angiomyolipomas and 2 cases of oncocytomas. The ADCs showed significant differences among benign tumors ([0.90 ± 0.52] × 10-3 mm 2 /s), ccRCCs ([1.53 ± 0.31] × 10-3 mm 2 /s) and the normal renal parenchyma ([2.22 ± 0.12] × 10-3 mm 2 /s) (P < 0.001). Moreover, there was statistically significant difference between high and low-grade ccRCCs (P = 0.004). Using a cut-off ADC of 1.36 × 10-3 mm 2 /s, DW-MRI resulted in an area under the curve (AUC), sensitivity, and specificity equal to 0.839, 75.8%, and 87.5%, respectively. Nonenhanced MRI alone and the combination of imaging methods led to an AUC, sensitivity and specificity equal to 0.919, 93.9%, and 81.2%, 0.998, 97%, and 100%, respectively. The Logistic regression showed that the location of the center of the tumor (inside the contour of the kidney) and appearance of stiff blood vessel were significantly helpful for diagnosing ccRCCs. CONCLUSIONS DW-MRI has potential in distinguishing ccRCCs from benign lesions in human small solid renal tumors (≤ 4 cm), and in increasing the accuracy for diagnosing ccRCCs when combined with nonenhanced MRI.
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Affiliation(s)
- Han-Mei Zhang
- Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Ying-Hua Wu
- Department of Radiology, The Second Clinical Medicine School, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 610041, China
| | - Qi Gan
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Xiao Lyu
- Department of Urology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Xiang-Lan Zhu
- Department of Pathology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Min Kuang
- Department of Radiology, The Second Clinical Medicine School, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 610041, China
| | - Rong-Bo Liu
- Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Zi-Xing Huang
- Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Fang Yuan
- Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Xi-Jiao Liu
- Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Bin Song
- Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
- Address for correspondence: Dr. Bin Song, Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China E-Mail:
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Raman SP, Chen Y, Schroeder JL, Huang P, Fishman EK. CT texture analysis of renal masses: pilot study using random forest classification for prediction of pathology. Acad Radiol 2014; 21:1587-96. [PMID: 25239842 DOI: 10.1016/j.acra.2014.07.023] [Citation(s) in RCA: 118] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 07/16/2014] [Accepted: 07/26/2014] [Indexed: 02/06/2023]
Abstract
RATIONALE AND OBJECTIVES Computed tomography texture analysis (CTTA) allows quantification of heterogeneity within a region of interest. This study investigates the possibility of distinguishing between several common renal masses using CTTA-derived parameters by developing and validating a predictive model. MATERIALS AND METHODS CTTA software was used to analyze 20 clear cell renal cell carcinomas (RCCs), 20 papillary RCCs, 20 oncocytomas, and 20 renal cysts. Regions of interest were drawn around each mass on multiple slices in the arterial, venous, and delayed phases on renal mass protocol CT scans. Unfiltered images and spatial band-pass filtered images were analyzed to quantify heterogeneity. Random forest method was used to construct a predictive model to classify lesions using quantitative parameters. The model was externally validated on a separate set of 19 unknown cases. RESULTS The random forest model correctly categorized oncocytomas in 89% of cases (sensitivity = 89%, specificity = 99%), clear cell RCCs in 91% of cases (sensitivity = 91%, specificity = 97%), cysts in 100% of cases (sensitivity = 100%, specificity = 100%), and papillary RCCs in 100% of cases (sensitivity = 100%, specificity = 98%). CONCLUSIONS CTTA, in conjunction with random forest modeling, demonstrates promise as a tool to characterize lesions. Various renal masses were accurately classified using quantitative information derived from routine scans.
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Affiliation(s)
- Siva P Raman
- Department of Radiology, JHOC 3251, Johns Hopkins University, 601 N. Caroline Street, Baltimore, MD 21287.
| | - Yifei Chen
- Department of Radiology, JHOC 3251, Johns Hopkins University, 601 N. Caroline Street, Baltimore, MD 21287
| | - James L Schroeder
- Department of Radiology, JHOC 3251, Johns Hopkins University, 601 N. Caroline Street, Baltimore, MD 21287
| | - Peng Huang
- Biostatistics and Bioinformatics Division, Department of Oncology, Johns Hopkins University, Baltimore, Maryland
| | - Elliot K Fishman
- Department of Radiology, JHOC 3251, Johns Hopkins University, 601 N. Caroline Street, Baltimore, MD 21287
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Sevcenco S, Heinz-Peer G, Ponhold L, Javor D, Kuehhas F, Klingler H, Remzi M, Weibl P, Shariat S, Baltzer P. Utility and limitations of 3-Tesla diffusion-weighted magnetic resonance imaging for differentiation of renal tumors. Eur J Radiol 2014; 83:909-913. [DOI: 10.1016/j.ejrad.2014.02.026] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 02/21/2014] [Accepted: 02/27/2014] [Indexed: 01/25/2023]
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Sevcenco S, Krssak M, Javor D, Ponhold L, Kuehhas FE, Fajkovic H, Haitel A, Shariat SF, Baltzer PA. Diagnosis of renal tumors by in vivo proton magnetic resonance spectroscopy. World J Urol 2014; 33:17-23. [DOI: 10.1007/s00345-014-1272-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Accepted: 02/26/2014] [Indexed: 10/25/2022] Open
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Chromophobe renal cell carcinoma: multiphase MDCT enhancement patterns and morphologic features. AJR Am J Roentgenol 2014; 201:1268-76. [PMID: 24261366 DOI: 10.2214/ajr.13.10813] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The purpose of this investigation is to retrospectively describe morphologic features, enhancement characteristics, and clinical outcomes in a series of pathologically proven chromophobe renal cell carcinomas (RCCs). MATERIALS AND METHODS Thirty-five patients who were imaged at a single institution between 2005 and 2012 with pathologically proven chromophobe RCC were identified, all of whom underwent preoperative renal protocol CT (unenhanced, arterial, venous, and delayed images). The morphologic characteristics of each tumor (e.g., necrosis, tumor composition, and calcification), as well as attenuation values (in Hounsfield units) of the tumor, aorta, inferior vena cava, and kidney were evaluated by a board-certified radiologist. In addition, information regarding patient demographics and survival was obtained by a separate radiologist from the electronic medical record. RESULTS Sixty percent of the patients were men, with a mean age of 60.2 years. Forty-six percent of cases were incidentally identified, without patient symptoms. None of the patients had evidence of distant metastatic disease, either on initial staging CT or over the course of follow-up (mean, 2.0 years). Mean maximal tumor diameter was 5.24 cm. Forty-six percent of tumors were homogeneous, 85% of lesions were either completely solid or mostly solid, 14% showed calcifications, and 34% showed a central scar or necrosis. Mean maximum attenuation values were 87.9 HU (arterial phase), 83.9 HU (venous phase), and 60.6 HU (delayed phase), with an average delayed washout of 31%. Tumor-to-cortex ratios for the three enhanced phases were 0.59, 0.48, and 0.50, respectively. CONCLUSION Chromophobe RCCs were found to have a wider variability of CT features than previously reported, although they do have a greater propensity for homogeneity and the presence of a central scar or necrosis. Their enhancement characteristics fall in between those of clear cell and papillary RCC, although there is considerable overlap.
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Liu K, Xie P, Peng W, Zhou Z. Renal carcinomas associated with Xp11.2 translocations/TFE3 gene fusions: findings on MRI and computed tomography imaging. J Magn Reson Imaging 2013; 40:440-7. [PMID: 24136829 DOI: 10.1002/jmri.24349] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Accepted: 07/29/2013] [Indexed: 12/16/2022] Open
Abstract
PURPOSE To retrospectively analyze MRI and computed tomographic (CT) findings from renal carcinomas associated with Xp11.2 translocations/TFE3 gene fusions (Xp11-RCC). MATERIALS AND METHODS Institutional review board permission was obtained to review patient medical records, and the requirement for informed consent was waved . The clinical and MRI/CT features of five cases with Xp11-RCC that were confirmed by pathology were analyzed retrospectively. The image characteristics included the lesion location and size, contribution of cystic and solid components, intratumoral necrosis or hemorrhage, invasion of perinephric tissue and renal sinus, lymphadenopathy, major venous or arterial vascular invasion, pattern of the tumor growth, intratumor calcification and lipids, homogeneity of SI on T2-weighted images, attenuation and SI of the mass with respect to the normal renal cortex on precontrast and contrasted CT/MRI images, tumor SIs, tumor attenuations and tumor-to-cortex indices, homogeneity of enhancement on the contrasted images. RESULTS The mean age was 32 years (range, 15-47 years). Most patients (4/5) were women. All tumors showed a cortical location. The average tumor size was 9 cm (range, 4-18 cm). Four tumors comprised a predominantly solid lesion with focal necrosis, and one tumor comprised a solid lesion with significant necrosis. All tumors showed intertumor hemorrhage, infiltrative growth and invasion of the perirenal adipose/renal sinus. Four cases showed retroperitoneal lymphadenopathy, of which one case showed simultaneous mediastinal and supraclavicular lymphadenopathy. All tumors from four cases showed mild hyperintensity on T1-weighted MRI images, and three tumors showed hypointensity on T2-weighted MRI images relative to the renal cortex except for 1 tumor that showed significant hemorrhage and a relative hyperintensity. For 3 cases who were imaged with CT, two tumors imaged using nonenhanced CT images showed mild hyperdensity relative to the renal cortex. Calcification was noted in all three tumors. All tumors showed mild, persistent enhancement. CONCLUSION Typical Xp11-RCC manifests as an advanced, solid renal mass with mild persistent enhancement, a prevalence of intertumor hemorrhage/calcification, and a cortical epicenter location. The predilection for children and young adults is a useful clinical feature when confirming a diagnosis of Xp11-RCC.
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Affiliation(s)
- Kefu Liu
- Department of Radiology, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou, Jiangsu, China; Department of Radiology, Fudan University Shanghai Cancer Center; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
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Three-Tesla dynamic contrast-enhanced MRI: a critical assessment of its use for differentiation of renal lesion subtypes. World J Urol 2013; 32:215-20. [DOI: 10.1007/s00345-013-1177-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Accepted: 09/28/2013] [Indexed: 12/31/2022] Open
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