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Kwong A, Mitchell A, Wang D, McGahan JP. Etiology of Small Echogenic Renal Masses. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2022; 41:2567-2575. [PMID: 35043978 DOI: 10.1002/jum.15946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 12/09/2021] [Accepted: 01/02/2022] [Indexed: 06/14/2023]
Abstract
OBJECTIVES There has been controversy on how frequently small echogenic masses are angiomyolipomas (AMLs) versus renal cell carcinoma (RCC) and how best to manage these echogenic masses. We performed this study to determine the etiologies of echogenic renal masses and compare them with prior publications to reach possible management decisions. METHODS This is a retrospective chart review of all consecutive renal ultrasound examinations performed at our institution between January 2015 and December 2016, with an ultrasound report finding containing the wording "echogenic" and "mass." This yielded 6462 total examinations. A total of 107 echogenic lesions met inclusion and exclusion criteria with correlative computed tomography, pathology, or long-term (>5 years) follow-up ultrasound. These lesions were stratified into those that were ≤2 cm and those that were >2 cm. RESULTS Almost all masses were benign, with the majority (79/107) being AMLs (73.8%); 64 of the 79 (81%) of the AMLs were in female patients. Two of the 107 masses were RCCs, and 1 mass was an oncocytic neoplasm. There were 77 of the masses that were ≤2 cm and these masses were benign except for one lesion of an oncocytic neoplasm. There were 30 of the 107 masses >2 cm, with 2 of the 30 (6.7%) being RCCs. CONCLUSIONS Incidental echogenic renal masses are most commonly AMLs. However, some masses may be RCCs. In comparing our results with the prior literature, we feel that small echogenic renal masses ≤1 cm usually require no further evaluation, while masses greater than that size require other imaging.
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Affiliation(s)
- Austin Kwong
- Department of Radiology, UC Davis Health SOM, Sacramento, California, USA
| | - Ana Mitchell
- Department of Radiology, UC Davis Health SOM, Sacramento, California, USA
| | - Danielle Wang
- Department of Radiology, UC Davis Health SOM, Sacramento, California, USA
| | - John P McGahan
- Department of Radiology, UC Davis Health SOM, Sacramento, California, USA
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Elbanna KY, Jang HJ, Kim TK, Khalili K, Guimarães LS, Atri M. The added value of contrast-enhanced ultrasound in evaluation of indeterminate small solid renal masses and risk stratification of cystic renal lesions. Eur Radiol 2021; 31:8468-8477. [PMID: 33912992 DOI: 10.1007/s00330-021-07964-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Revised: 02/09/2021] [Accepted: 03/29/2021] [Indexed: 11/25/2022]
Abstract
OBJECTIVES To investigate accuracy of contrast-enhanced ultrasound (CEUS) to characterize indeterminate small solid renal masses (sSRMs), excluding lipid-rich AMLs, and cystic renal masses (CRMs) according to the proposed Bosniak Classification 2019 MATERIALS AND METHODS: CEUS of pathology-proven CRMs and sSRMs (without definite enhancement or macroscopic fat on CT/MRI), and CRMs with ≥18 months follow-up were retrospectively reviewed. Two radiologists blindly categorized CRMs according to new Bosniak Classification on CT/MRI. On CEUS, two other radiologists evaluated arterial-phase enhancement of sSRMs relative to renal cortex and categorized CRMs following new Bosniak Classification. Fisher's exact/chi-squared test was used to compare categorical variables, and Cohen κ statistics for inter-observer agreement RESULTS: A total of 237 patients had 241 lesions: 161 pathology-proven sSRMs (122 malignant and 39 benign), 29 pathology-proven CRMs, 51 CRMs with adequate follow-up. Arterial-phase enhancement < renal cortex predicted malignancy with specificity of 97.4% (38/39) (CI 85.6-99.9%), and positive predictive value (PPV) of 98.2% (54/55) (CI 90.4-99.9%). Inter-observer kappa was 0.95. In pathology-proven CRMS, sensitivity of CEUS vs CT/MRI was 100% (15/15) (CI 79.6-100%) vs 60% (9/15) (CI 35.8-80.1%) (p value = .002) and negative predictive value (NPV) 100% (2/2) (CI 17.8-100%) vs 25% (2/8 ) (CI 4.4-59.1%) (p value < 0.0001), with similar specificity (50%) and PPV- 88.2% (15/17) (CI 65.7-97.9%) vs 81.8% (9/11) (CI 52.3-96.8%) ( p value = 0.586). Bosniak Classification inter-observer kappa was 0.92 for CEUS vs 0.68 for CT/MRI (p value = 0.009). CONCLUSION In our cohort, CEUS had high specificity and PPV to diagnose RCC in sSRMs excluding lipid-rich AML. CEUS had significantly higher sensitivity/NPV to diagnose malignancy in CRMs as compared to CT/MRI. KEY POINTS • Once lipid-rich AML is excluded by the other modalities, sSRM arterial phase hypo-enhancement relative to renal cortex on CEUS yielded high specificity (97.4%) and PPV (98.2%) to diagnose RCC. • When applying the proposed Bosniak Classification 2019, CEUS showed higher sensitivity compared to CT/MRI (100% vs 60%), p value=.0024, in the stratification of cystic renal masses to diagnose malignancy. • CEUS may reduce the number of CT/MRI Bosniak IIF lesions by assigning them to either II or III/IV categories.
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Affiliation(s)
- Khaled Y Elbanna
- Toronto Joint Department of Medical Imaging, University Health Network, Sinai Health System and Women's College Hospital, University of Toronto, Toronto, ON, Canada
| | - Hyun-Jung Jang
- Toronto Joint Department of Medical Imaging, University Health Network, Sinai Health System and Women's College Hospital, University of Toronto, Toronto, ON, Canada
| | - Tae Kyoung Kim
- Toronto Joint Department of Medical Imaging, University Health Network, Sinai Health System and Women's College Hospital, University of Toronto, Toronto, ON, Canada
| | - Korosh Khalili
- Toronto Joint Department of Medical Imaging, University Health Network, Sinai Health System and Women's College Hospital, University of Toronto, Toronto, ON, Canada
| | - Luís S Guimarães
- Toronto Joint Department of Medical Imaging, University Health Network, Sinai Health System and Women's College Hospital, University of Toronto, Toronto, ON, Canada
| | - Mostafa Atri
- Toronto Joint Department of Medical Imaging, University Health Network, Sinai Health System and Women's College Hospital, University of Toronto, Toronto, ON, Canada.
- Department of Medical Imaging, Toronto General Hospital, University of Toronto, 585 University Avenue, Toronto, ON M5G 2N2, Canada.
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Renal Angiomyolipoma: Radiologic Classification and Imaging Features According to the Amount of Fat. AJR Am J Roentgenol 2017; 209:826-835. [PMID: 28726505 DOI: 10.2214/ajr.17.17973] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE The purposes of this article are to introduce the radiologic classifications of renal angiomyolipoma (AML) and the clinical implications, to show the imaging features of each type of AML, and to describe which types of AML should be biopsied. CONCLUSION Renal AML can be classified according to amount of fat as fat rich, fat poor, or fat invisible. To detect fat, one needs to thoroughly evaluate the entire AML by controlling the size and shape of the ROI. Fat-invisible AML should be biopsied, and fat-poor AML requires further investigation to determine whether biopsy is necessary to differentiate it from renal cell carcinoma. If differentiation between AML and renal cell carcinoma is not clear with CT and MRI, percutaneous biopsy may be performed.
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Habibollahi P, Chauhan A, Sultan LR, Jones LP, Sehgal CM. Can "Tumor-to-Cortex Echogenicity Ratio" Differentiate Angiomyolipomas from Other Hyper-Echoic Renal Masses. ULTRASOUND IN MEDICINE & BIOLOGY 2017; 43:1372-1377. [PMID: 28400076 DOI: 10.1016/j.ultrasmedbio.2017.02.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 02/20/2017] [Accepted: 02/21/2017] [Indexed: 06/07/2023]
Abstract
A retrospective study was performed to evaluate the diagnostic value of tumor-to-cortex echogenicity ratio (TCER) in the characterization of hyper-echoic renal masses. The radiology database was queried between 2012 and 2014 for hyper-echoic renal masses on the basis of defined exclusion and inclusion criteria. Each included mass was characterized as either an angiomyolipoma (AML) or a non-AML based on pre-defined criteria. The ratio of renal mass echogenicity to that of adjacent renal cortex (TCER) was calculated for each mass using commercially available software. A total of 70 masses in 65 patients were identified, including 49 AMLs. TCER values >2.26 were associated with a sensitivity and specificity of 81.6% and 71.4%, respectively, for diagnosis of AML. Moreover, TCER values >3.98 resulted in 100% specificity for AML diagnosis with a sensitivity of 28.6%. These findings suggest that the TCER may be a valuable tool for the characterization of hyper-echoic renal masses.
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Affiliation(s)
- Peiman Habibollahi
- Department of Radiology, Hospital of the University of Pennsylvania, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Anil Chauhan
- Department of Radiology, Hospital of the University of Pennsylvania, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
| | - Laith R Sultan
- Department of Radiology, Hospital of the University of Pennsylvania, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Lisa P Jones
- Department of Radiology, Hospital of the University of Pennsylvania, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Chandra M Sehgal
- Department of Radiology, Hospital of the University of Pennsylvania, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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Woo S, Kim SH. Differentiation of Small, Solid Renal Masses: A Pattern Recognition Approach. Semin Ultrasound CT MR 2017; 38:28-36. [DOI: 10.1053/j.sult.2016.08.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Roy C, Gengler L, Sauer B, Lang H. [Role of contrast enhanced US in the evaluation of renal tumors]. ACTA ACUST UNITED AC 2009; 89:1735-44. [PMID: 19106830 DOI: 10.1016/s0221-0363(08)74478-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To evaluate the role of contrast enhanced US in the characterization of renal tumors. Materials and methods. Eighty-six renal tumors (33 solid, 53 cystic) underwent contrast enhanced US after indeterminate CT/MRI (67 lesions) or US (19 lesions). Pathological correlation was available for 42 cases, and follow-up at 3 and 6 months was available for 13 cases. Diagnosis was achieved in 21 cases. Lesions included: 19 renal cell carcinomas (4 conventional, 14 papillary, 1 tubulocystic), 5 oncocytomas, 3 metastases, 6 pseudomasses, and 53 cystic lesions including 6 malignant tumors. RESULTS Solid tumors were correctly identified in 100% of cases. Characterization of solid tumors was possible with specificity of 92.9% for papillary carcinoma, 57.1% for clear cell carcinoma, and 100% for oncocytoma. The specificity for distinguishing solid benign from solid malignant tumor was 100% based on the presence of hypoechogenicity relative to normal renal parenchyma on delayed imaging. Contrast enhanced US allowed reclassification of 23 indeterminate lesions on conventional US. It is of limited value for large cystic lesions or cystic lesions with extensive wall calcification. CONCLUSION Contrast enhanced US is easily performed in clinical practice and allows improved characterization of some renal tumors compared to other cross sectional imaging techniques.
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Affiliation(s)
- C Roy
- Service de Radiologie B, Centre Hospitalier Universitaire de Strasbourg, Hôpital Civil, 1, place de l'hôpital, BP426, 67091 Strasbourg Cedex, France.
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Fan L, Lianfang D, Jinfang X, Yijin S, Ying W. Diagnostic efficacy of contrast-enhanced ultrasonography in solid renal parenchymal lesions with maximum diameters of 5 cm. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2008; 27:875-885. [PMID: 18499847 DOI: 10.7863/jum.2008.27.6.875] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
OBJECTIVE The purpose of this study was to evaluate the diagnostic efficacy of contrast-enhanced ultrasonography (CEUS) using a sulfur hexafluoride contrast agent and the cadence contrast pulse sequencing mode in differentiating solid renal parenchymal lesions (SRPLs) with a maximum diameter of 5 cm. METHODS Seventy-one patients with 72 SRPLs with a maximum diameter of 5 cm underwent conventional ultrasonographic and CEUS examinations in our department. The final diagnoses were 44 renal cell carcinomas (RCCs; confirmed by pathologic examination), 24 renal angiomyolipomas (4 by pathologic examination and 20 by computed tomography, magnetic resonance imaging, and follow-up studies), 1 oncocytoma (by pathologic examination), 2 hypertrophied columns of Bertin, and 1 renal abscess (both by computed tomography, magnetic resonance imaging, and follow-up studies). Three observers who were blinded to other results and the final diagnoses reviewed the conventional ultrasonographic and CEUS images. RESULTS Hyperenhancement in the late phase (30-90 seconds after agent injection) was the most important finding for predicting SRPLs with a maximum diameter of 5 cm to be RCCs. With this criterion, the specificity and sensitivity for diagnosing solid RCCs (<or= 5 cm) were 96.4% and 77.3%, respectively. Heterogeneous enhancement was another valuable finding suggestive of RCCs. Most renal angiomyolipomas were homogeneously enhanced with hypoenhancement in the arterial and late phases. Hypertrophied columns of Bertin could be reliably differentiated on CEUS; however, there was an overlap of CEUS appearances between some benign lesions and hypovascular RCCs. CONCLUSIONS Contrast-enhanced ultrasonography could be an effective and necessary examination for differentially diagnosing SRPLs with a maximum diameter of 5 cm.
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Affiliation(s)
- Li Fan
- Department of Ultrasound, Shanghai Jiaotong University Affiliated First People's Hospital, 85 Wu Jin Rd, 200080 Shanghai, China
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Farrelly C, Delaney H, McDermott R, Malone D. Do all non-calcified echogenic renal lesions found on ultrasound need further evaluation with CT? ACTA ACUST UNITED AC 2007; 33:44-7. [PMID: 17849156 DOI: 10.1007/s00261-007-9306-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND This is a study using Evidence Based Practice (EBP) technique to evaluate if non-calcified renal lesions detected with ultrasound, suspected to represent an angiomyolipoma (AML), need a CT to rule out a renal cell carcinoma (RCC). METHODS The secondary and primary literature were searched for all relevant information. This was appraised for validity and strength. The results from the papers with the highest level of evidence were grouped together and analyzed. RESULTS Three papers in the primary literature constituted the highest level of evidence. In total these three papers examined 220 lesions. The prevalence of AML was 45% in this sample. Overall, hyperechoic non-calcified renal lesions had a sensitivity of 0.99 (95% confidence interval (CI) 0.97-1.00), a specificity of 0.43 (95% CI 0.34-0.51), a positive predictive value (PPV) of 0.58 and a negative predictive value (NPV) of 0.98 for AMLs. 57.4% of RCCs were hyperechoic to renal parenchyma. Two of the studies found that posterior acoustic shadowing had a sensitivity of 0.34 (95% CI 0.40-0.56) and a specificity of 1.0 (95% CI 1.0-1.0) for AML. CONCLUSIONS From the surprisingly limited evidence available in the literature, it must be concluded that all non-calcified echogenic renal lesions detected with ultrasound need a CT to rule out an RCC.
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Affiliation(s)
- Cormac Farrelly
- Radiology Department, St. James's Hospital, James's Street, Dublin 8, Dublin, Ireland.
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Ahmed M, Aslam M, Ahmed J, Faraz HA, Almahfouz A, Al Arifi A, Raef H, Dayel FA. Renal metastases from thyroid cancer masquerading as renal angiomyolipoma on ultrasonography. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2006; 25:1459-64. [PMID: 17060435 DOI: 10.7863/jum.2006.25.11.1459] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Affiliation(s)
- Mohammed Ahmed
- Department of Medicine, MBC-46, King Faisal Specialist Hospital and Research Center, Riyadh 11211, Saudi Arabia.
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Abstract
Ultrasonography and CT have allowed improved detection of renal mass lesions. Though ultrasonography is less sensitive in the characterization of the renal mass lesions, it is often the first imaging modality for evacuation of the kidneys. This article gives an overview of the benign and malignant renal mass lesions and the role of ultrasonography in their characterization.
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Affiliation(s)
- Raj Mohan Paspulati
- Department of Radiology, University Hospitals of Cleveland, Case Western Reserve University, 11100 Euclid Avenue, Cleveland, OH 44106, USA.
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Pereira JM, Sirlin CB, Pinto PS, Casola G. CT and MR imaging of extrahepatic fatty masses of the abdomen and pelvis: techniques, diagnosis, differential diagnosis, and pitfalls. Radiographics 2006; 25:69-85. [PMID: 15653588 DOI: 10.1148/rg.251045074] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The differential diagnosis of extrahepatic abdominopelvic masses is wide. Demonstration of fat within a lesion at noninvasive imaging is an important clue for narrowing the differential diagnosis. Macroscopic fat is readily identified with both computed tomography (CT) and magnetic resonance (MR) imaging. Demonstration of microscopic fat is more difficult and may require special techniques. Identification of fat with CT is based on x-ray resorption and therefore on the attenuation (typically less than -20 HU). Several MR imaging techniques have been developed for fat suppression. Two of the most widely available are spectroscopic fat saturation and chemical shift (in-phase/opposed-phase) imaging. Entities with predominantly macroscopic fat include myelolipoma, angiomyolipoma, teratoma, liposarcoma, lipoma, epiploic appendagitis, omental infarction, and mesenteric panniculitis. Lesions with predominantly microscopic fat include adrenal adenoma and some teratomas. Other fat-containing entities involve the mesentery and bowel wall; these include fibrofatty mesenteric proliferation and submucosal fat deposition.
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Affiliation(s)
- Jose M Pereira
- Department of Radiology, Porto Medical School, Hospital S. João, Porto, Portugal
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Ascenti G, Gaeta M, Magno C, Mazziotti S, Blandino A, Melloni D, Zimbaro G. Contrast-enhanced second-harmonic sonography in the detection of pseudocapsule in renal cell carcinoma. AJR Am J Roentgenol 2004; 182:1525-30. [PMID: 15150001 DOI: 10.2214/ajr.182.6.1821525] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
OBJECTIVE Our purpose was to assess the capacity of contrast-enhanced second-harmonic sonography to detect a pseudocapsule in renal masses compared with conventional gray-scale sonography. SUBJECTS AND METHODS. Thirty-two patients with 40 renal masses suspicious for renal cancer (mean diameter, 3.1 cm) were prospectively studied with contrast-enhanced second-harmonic sonography during IV administration of a second-generation sonographic contrast agent. The sonographic criteria for the presence of a pseudocapsule were a peritumoral hypoanechoic halo on conventional gray-scale imaging and a rim of perilesional enhancement, increasing in the tardive phase of the examination, on contrast-enhanced second-harmonic imaging. Multiphasic helical CT or dynamic MRI or both were performed in all patients. RESULTS Final diagnoses of the 40 renal masses were as follows: hemorrhagic cysts, five; angiomyolipomas, four; lymphomas, four; metastasis from lung cancer, one; and renal cell carcinomas (RCCs), 26. Histologic diagnosis of RCC was surgically obtained in all patients. Nephron-sparing surgery was performed in 12 of 26 RCCs, and radical nephrectomy was performed in the remaining 14. At pathologic examination, pseudocapsule was found in 14 (53.8%) of 26 RCCs. On conventional sonography, the presence of a pseudocapsule was detected in 3 of 14 RCCs (sensitivity, 21%). Sonographic contrast-enhanced harmonic imaging revealed the presence of pseudocapsule in 12 of 14 RCCs (sensitivity, 85.7%). In the remaining 12 RCCs with either absent or extensive neoplastic infiltration of pseudocapsule seen at pathologic evaluation, pseudocapsule was not visible on either conventional or contrast-enhanced second-harmonic sonography. The pseudocapsule was not visible in any of the 14 noncancerous renal masses on either conventional or contrast-enhanced sonography. CONCLUSION Sonographic contrast-specific imaging with a second-generation contrast agent is effective in improving the sonographic visualization of tumoral pseudocapsule. This finding could be useful both in the sonographic diagnosis and in the choice of conservative surgery for renal cell carcinoma. The potential role of second-harmonic contrast-enhanced sonography in the management of renal cell carcinoma should be investigated in larger series and compared with the findings of state-of-the-art MRI and CT.
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Affiliation(s)
- Giorgio Ascenti
- Department of Radiological Sciences, University of Messina, Via Consolare Valeria-Gazzi, Messina 98100, Italy.
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Heidenreich A, Hegele A, Varga Z, von Knobloch R, Hofmann R. Nephron-sparing surgery for renal angiomyolipoma. Eur Urol 2002; 41:267-73. [PMID: 12180227 DOI: 10.1016/s0302-2838(02)00015-5] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
INTRODUCTION Renal angiomyolipoma (RAML) is a benign tumor composed of varying amounts of mature adipose tissue, smooth muscle and thick-walled blood vessels. RAML tend to grow over time requiring active intervention due to serious associated complications, such as hemorrhage and pain. Although RAML is an ideal tumor for organ preservation, data concerning efficacy of nephron-sparing surgery (NSS) are sparse. The aim of the study was to evaluate the efficacy of NSS in RAML with regard to renal function, tumor recurrence and surgical feasibility. PATIENTS AND METHODS Charts of patients with pathologically confirmed RAML were reviewed and data recorded: tumor size, associated symptoms, intraoperative blood loss, serum creatinine, follow-up data with regard to tumor recurrence and long-term renal function. A total of 28 patients were identified with RAML who underwent NSS because of tumor size > 4 cm, pain and/or to rule out malignancy due to radiographic features of uncertain interpretation. RESULTS The median follow-up of all patients is 58 (3-114) months; median age was 55.6 (34-78) years, 24 patients were women, 4 patients were men. None of the patients developed a local recurrence. Median size of enucleated tumors was 5.5 (2.5-15) cm; indication for NSS was symptomatic tumor with hemorrhage in 4 patients (16%), prophylaxis of hemorrhage in 5 patients (20%) and radiographic features suspicious for malignancy in 16 patients (64%). In those cases, unenhanced and enhanced CT scans exhibit a hyperdense and a hypodense lesion as compared to the adjacent normal renal cortex, respectively. There were no intraoperative complications, median blood loss was 320 (50-1200) ml, none of the patients required blood transfusions. Post-operative course was uneventful in 26 patients (96%), 2 patients (7.1%) developed a urinary fistula managed by an endoluminal stent. Pre-operative serum creatinine was 0.9 (0.7-1.3) mg/dl, post-operative creatinine was 1.23 (0.7-1.5) mg/dl and serum creatinine at last follow-up was 0.95 (0.7-1.2) mg/dl. CONCLUSIONS NSS can be performed with a high success rate in RAML when surgical management is indicated. Long-term follow-up reveals no local tumor recurrences and stable renal function even in patients with a solitary kidney.
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Affiliation(s)
- Axel Heidenreich
- Department of Urology, Philipps University, Baldingerstrasse, 35043 Marburg, Germany.
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