Solid Renal Cell Carcinoma Research Articles

Eosinophilic Solid and Cystic Renal Cell Carcinoma (ESC RCC): Further Morphologic and Molecular Characterization of ESC RCC as a Distinct Entity.

Eosinophilic solid and cystic renal cell carcinoma (ESC RCC) has been recently described as a unique and indolent renal neoplasm, found in female patients with and without tuberous sclerosis complex. Although ESC RCC has a distinct morphology and frequent CK20 reactivity, its molecular karyotype has been previously studied only in few cases. We identified 19 ESC RCC from multiple institutions; all patients were female individuals without clinical features of tuberous sclerosis complex. Molecular karyotyping was performed in 13 cases (12 with informative result). The median age was 55 years (range: 32 to 79 y). The tumors were yellow-gray with a median size of 31 mm (range: 12 to 135 mm) and showed solid and cystic gross appearance. All tumors demonstrated typical microscopic features with solid areas admixed with variably sized macrocysts and microcysts. The cells showed eosinophilic cytoplasm with granular cytoplasmic stippling and round-to-oval nuclei. CK20 was positive in 14/19 (74%) cases. Stage pT1 was found in 17/19 (89%) patients (pT1a in 12, pT1b in 5); 1 patient each had pT2a and pT3a. A total of 15/16 patients with available follow-up were alive and without evidence of disease progression, after 1 to 169 months (median: 44 mo; mean: 49.6 mo); 3 died of other causes. The most common copy number gains were 16p13.3-16q23.1 (33% to 67%), 7p21.2-7q36.2 (42% to 50%), 13q14.2 (33%), and 19p12 (33%). The most common copy number losses included Xp11.21 (42%) and 22q11.23 (33%). Loss of heterozygosity was most frequently found at 16p11.2-11.1 (75%), Xq11.1-13.1 (75%), Xq13.1-21.1 (33%), 11p11.2-11.11 (33%), 9q21.1-22.2 (33%), and 9q33.1 (33%). ESC RCC demonstrates common molecular karyotype alterations, which further support its distinct nature.

Applications of contrast-enhanced ultrasound in the kidney.

Incidental discovery of renal lesions on cross-sectional imaging studies performed for other indications is not uncommon. With the increased reliance on medical imaging, the number of incidentally detected renal lesions has also grown over time. While simple cysts account for the majority of these lesions, the presence of complex features within a cystic lesion, such as septations and solid components, can present a confusing picture. Solid lesions, too, can be indeterminate, and distinguishing between benign solid masses (like lipid-poor angiomyolipomas and oncocytomas) and renal cell carcinoma affects patient management and can prevent unnecessary interventions. Indeterminate renal lesions are traditionally further characterized by multiphase imaging, such as contrast-enhanced computed tomography and magnetic resonance imaging. Contrast-enhanced ultrasound (CEUS) is a new, relatively inexpensive technique that has become increasingly employed in the diagnostic workup of indeterminate renal lesions. With its lack of nephrotoxicity, the absence of ionizing radiation, and the ability to evaluate the enhancement pattern of renal lesions quickly and in real-time, CEUS has unique advantages over traditional imaging modalities. This article provides an overview of the current clinical applications of CEUS in characterizing renal lesions, both cystic and solid. Additional applications of CEUS in the kidney, including its roles in renal transplant evaluation and guidance for percutaneous biopsy, will also be briefly discussed.

Statistical clustering of parametric maps from dynamic contrast enhanced MRI and an associated decision tree model for non-invasive tumour grading of T1b solid clear cell renal cell carcinoma.

To apply a statistical clustering algorithm to combine information from dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) into a single tumour map to distinguish high-grade from low-grade T1b clear cell renal cell carcinoma (ccRCC). This prospective, Institutional Review Board -approved, Health Insurance Portability and Accountability Act -compliant study included 18 patients with solid T1b ccRCC who underwent pre-surgical DCE MRI. After statistical clustering of the parametric maps of the transfer constant between the intravascular and extravascular space (K trans ), rate constant (K ep ) and initial area under the concentration curve (iAUC) with a fuzzy c-means (FCM) algorithm, each tumour was segmented into three regions (low/medium/high active areas). Percentages of each region and tumour size were compared to tumour grade at histopathology. A decision-tree model was constructed to select the best parameter(s) to predict high-grade ccRCC. Seven high-grade and 11 low-grade T1b ccRCCs were included. High-grade histology was associated with higher percent high active areas (p = 0.0154) and this was the only feature selected by the decision tree model, which had a diagnostic performance of 78% accuracy, 86% sensitivity, 73% specificity, 67% positive predictive value and 89% negative predictive value. The FCM integrates multiple DCE-derived parameter maps and identifies tumour regions with unique pharmacokinetic characteristics. Using this approach, a decision tree model using criteria beyond size to predict tumour grade in T1b ccRCCs is proposed. • Tumour size did not correlate with tumour grade in T1b ccRCC. • Tumour heterogeneity can be analysed using statistical clustering via DCE-MRI parameters. • High-grade ccRCC has a larger percentage of high active area than low-grade ccRCCs. • A decision-tree model offers a simple way to differentiate high/low-grade ccRCCs.

Pax8, Napsin A, and CD10 as Immunohistochemical Markers of Canine Renal Cell Carcinoma.

Pax8, napsin A, and CD10 are useful immunohistochemical markers of human renal cell carcinoma (RCC); however, their diagnostic utility in canine RCC is unclear. Forty formalin-fixed paraffin-embedded renal cell carcinomas from dogs (15 papillary, 12 solid, and 13 tubular) and 10 metastases were evaluated for expression of Pax8, napsin A, and CD10. Thirty-nine (98%), 24 (60%), and 19 (50%) tumors expressed Pax8 (nuclear labeling), napsin A (cytoplasmic labeling), and CD10 (cytoplasmic and membranous labeling), respectively. Pax8 was expressed in 92% of solid, 100% of papillary, and 100% of tubular tumors. Napsin A was expressed in 58% of solid, 60% of papillary, and 62% of tubular RCC. CD10 was expressed in 33% of solid, 47% of papillary, and 62% of tubular RCC. Pax8 was expressed in 80% of the metastatic tumors, napsin A in 60%, and CD10 in 50%. Additionally, Pax8 immunoreactivity was stronger overall than that of napsin A or CD10. In summary, Pax8 is a more sensitive marker than napsin A or CD10 for primary and metastatic canine RCC; its nuclear and more intense reactivity also makes it easier to interpret. Tubular and papillary RCCs were more likely than solid RCC to express all 3 markers. These findings highlight the utility of Pax8 as an immunohistochemical marker in diagnosing all major subtypes of canine primary and metastatic renal cell carcinoma.

Renal cell carcinoma: applicability of the apparent coefficient of the diffusion-weighted estimated by MRI for improving their differential diagnosis, histologic subtyping, and differentiation grade.

Renal cell carcinoma (RCC) represents the most common malignant epithelial neoplasm of the kidney. Accurate assessment of the renal masses, defining the histologic subtype and the grade of differentiation of the tumor, is vital to ensure an adequate case management as well as for staging and prognosis. Recently, diffusion-weighted imaging (DWI) magnetic resonance imaging (MRI) tends to be increasingly appealing for the clinicians as an imaging procedure of choice for the diagnosis and staging of the RCC, which is predetermined by several advantages over CT. The goal of the survey was to assess the applicability of the apparent diffusion coefficient (ADC) of the DWI MRI for the differential diagnostics, histologic subtyping, and defining the grade of differentiation of the RCC. The study enrolled 288 adult patients with renal lesions: 188 patients with solid RCC-126 patients with clear cell subtype (ccRCC), 32 patients with papillary RCC (pRCC), 30 patients with chromophobe RCC (chRCC); 27 patient with cystic form or RCC (Bosniak cyst, category IV); 32 patients with renal angiomyolipoma (AML); 25 patients with renal oncocytoma (OC); and 16 patients with the renal abscess (AB). In total, 245 lesions were pathologically verified. As a reference, 19 healthy volunteers were included into the study. All patients underwent MRI of the kidneys, involving DWI with subsequent evaluation of the ADC. There was a reliable difference (p<0.05) in mean ADC values between the normal renal parenchyma (NRP), solid RCC of different histologic subtypes and grades, cystic RCC, and benign renal lesions. The mean ADC values obtained in the result of the study were (×10-3mm2/s): 2.47±0.12 in NRP, 1.63±0.29 in all solid RCCs, 1.82±0.22 in solid ccRCC (1.92±0.11-Fuhrman grade I, 1.84±0.14-Fuhrman grade II, 1.79±0.10-Fuhrman grade III, 1.72±0.06-Fuhrman grade IV), 1.61±0.07 in pRCC, 1.46±0.09 in chRCC, 2.68±0.11 in cystic RCC, 2.13±0.08 in AML, 2.26±0.06 in OC, and 3.30±0.07 in AB. The data received in our study demonstrate a substantial restriction of diffusion of hydrogen molecules in tissues of ccRCC in comparison with the healthy renal parenchyma preconditioned by the greater density of tumor. A statistically significant difference in mean ADC values of ccRCC with different grades of nuclear pleomorphism by Fuhrman was observed: Low-grade tumors showed higher mean ADC values compared to high-grade tumors. The modality of the MRI DWI along with ADC measurement allows to reliably differentiate between the solid RCC of main histologic subtypes and grades, cystic RCC, and the benign renal lesions.

Solid papillary renal cell carcinoma: clinicopathologic, morphologic, and immunohistochemical analysis of 10 cases and review of the literature.

Solid papillary renal cell carcinoma is rarely reported in the literature, and its tumor characteristics are not entirely compatible with the concept of 2 histological subtypes of papillary renal cell carcinoma (PRCC). Tumor is composed mostly of small compressed tubules and short abortive papillae giving solid appearance of monomorphic epithelial cells with scanty cytoplasm and small nuclei, sometimes mimicking spindle cells, without or with sparse true papillae. It shows immunohistochemical (+ CK7, + EMA, + AMACR) and genetic hallmarks (polysomy/trisomy 7/17, loss of Y) of conventional PRCC. About 53 cases have been described in the literature, with male predominance and age ranging from 17 to 82 years. By available follow-up data, solid PRCC has a favorable clinical course. We describe 10 cases compatible with the diagnosis of solid PRCC. All patients were males age range was from 34 to 70 years, and all but one were pT1 according to TNM 2009. On follow-up, 9 patients were without evidence of disease, and 1 had recurrent tumor. Size of the tumor ranged from 1.4 to 5.5 cm (mean, 3.32 cm). Tumors were well-circumscribed whitish to yellow masses with granular surface. Although solid architecture was a prominent morphologic feature, detailed analysis revealed that the tumors were composed of compressed short abortive papillae and compressed tubules admixed with true solid areas. Well-formed papillae were exceptionally present. All 10 cases were strongly and diffusely positive for CK7 and negative for WT-1. In conclusion, solid PRCC is a rare tumor with an incidence of less than 1% of all renal tumors. In majority of the cases, tumors were composed of tightly compressed tubular structures and short abortive papillae that render a solid morphologic appearance. Immunohistochemical and molecular features do not differ from conventional PRCC. Metanephric adenoma; epithelioid nephroblastoma; and, rarely, mucinous tubular and spindle cell carcinoma and oncocytic variant of PRCC should be considered in the differential diagnosis.

Solid Renal Cell Carcinomas With an Attenuation Similar to That of Water on Unenhanced CT.

Solid Renal Cell Carcinomas With an Attenuation Similar to That of Water on Unenhanced CT.

Reply to "Solid Renal Cell Carcinomas With an Attenuation Similar to That of Water on Unenhanced CT".

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Enhancement Threshold of Small (< 4 cm) Solid Renal Masses on CT.

The objective of our study was to determine whether small (< 4 cm) solid renal cell carcinomas (RCCs) enhance on CT below the published enhancement thresholds. For this retrospective study, we reviewed CT examinations of patients with pathologically characterized small solid renal masses. Patients with lipid-rich angiomyolipomas were excluded. The study included consecutive patients who had pathologically characterized small (< 4 cm) renal masses and had undergone CT during the un-enhanced phase and nephrographic phase (NP). Most CT examinations also included imaging during the corticomedullary phase (CMP); four patients did not have CMP images. The CT examinations were performed on a 64-MDCT scanner. Similar-sized ROIs were placed on each lesion on unenhanced and enhanced images and enhancement (in Hounsfield units) was calculated. Masses were considered solid with a threshold enhancement greater than either 15 or 20 HU. There were 137 masses in 137 patients, 90 men and 47 women (age range, 21-91 years; median age, 65 years). The renal masses were 1.0-3.9 cm (median, 2.4 cm). Of the 137 masses, 117 (85.4%) were malignant and 20 (14.6%) were benign. One malignant mass and three benign masses did not have CMP images. Twenty of the 116 (17.2%) renal cell carcinomas (RCCs) did not reach the 15-HU threshold enhancement on CMP images, nine of 117 masses (7.7%) did not reach the 15-HU enhancement threshold on NP images, and four of 117 masses (3.4%) did not reach the 15-HU enhancement threshold on both CMP and NP images. The numbers of masses that did not reach the 20-HU enhancement threshold were 24 of 116 masses (20.7%) on CMP images, 14 of 117 masses (11.9%) on NP images, and 11 of 117 masses (9.4%) on both CMP and NP images. Depending on the phase or enhancement threshold, 13.6-59.1% of papillary RCCs did not reach the enhancement threshold. A minority of small RCCs do not reach either a 15- or 20-HU enhancement threshold and might be misinterpreted as a hyperattenuating cyst. Most RCCs below these enhancement thresholds are papillary RCC.

Eosinophilic, Solid, and Cystic Renal Cell Carcinoma: Clinicopathologic Study of 16 Unique, Sporadic Neoplasms Occurring in Women.

A unique renal neoplasm characterized by eosinophilic cytoplasm and solid and cystic growth was recently reported in patients with tuberous sclerosis complex (TSC). We searched multiple institutional archives and consult files in an attempt to identify a sporadic counterpart. We identified 16 morphologically identical cases, all in women, without clinical features of TSC. The median age was 57 years (range, 31 to 75 y). Macroscopically, tumors were tan and had a solid and macrocystic (12) or only solid appearance (4). Average tumor size was 50 mm (median, 38.5 mm; range, 15 to 135 mm). Microscopically, the tumors showed solid areas admixed with variably sized macrocysts and microcysts that were lined by cells with a pronounced hobnail arrangement. The cells had voluminous eosinophilic cytoplasm with prominent granular cytoplasmic stippling and round to oval nuclei with prominent nucleoli. Scattered histiocytes and lymphocytes were invariably present. Thirteen of 16 patients were stage pT1; 2 were pT2, and 1 was pT3a. The cells demonstrated a distinct immunoprofile: nuclear PAX8 expression, predominant CK20-positive/CK7-negative phenotype, patchy AMACR staining, but no CD117 reactivity. Thirteen of 14 patients with follow-up were alive and without disease progression after 2 to 138 months (mean: 53 mo; median: 37.5 mo); 1 patient died of other causes. Although similar to a subset of renal cell carcinomas (RCCs) seen in TSC, we propose that sporadic "eosinophilic, solid, and cystic RCC," which occurs predominantly in female individuals and is characterized by distinct morphologic features, predominant CK20-positive/CK7-negative immunophenotype, and indolent behavior, represents a novel subtype of RCC.

Solid Renal Cell Carcinoma Measuring Water Attenuation (-10 to 20 HU) on Unenhanced CT.

The objectives of this study were to evaluate the incidence of solid renal cell carcinoma (RCC) with attenuation similar to that of water (-10 to 20 HU) on unenhanced CT and to examine imaging features that can allow RCC to be differentiated from simple cysts. We performed an enriched quantitative and qualitative retrospective analysis of consecutive patients who underwent unenhanced CT before resection of solid (noncystic and nonnecrotic) renal masses measuring < 5 cm from 2008 to 2013. In all, 93 patients with 96 tumors (55 clear cell, 27 papillary, and 14 chromophobe) were evaluated with unenhanced CT. Attenuation was measured at three standardized levels and compared using the Kruskal-Wallis test. Two radiologists independently assessed calcification, margin (smooth or irregular), and heterogeneity (homogeneous or heterogeneous). Results were compared using the chi-square test with Bonferroni correction. Mean ± SD attenuation values were 31.8 ± 9.6 HU (range, 11-63 HU) overall, 29.9 ± 8.8 HU (range, 11.0-49.0 HU) for clear cell tumors, 34.6 ± 10.3 HU (range, 20.3-63.0 HU) for papillary tumors, and 35.5 ± 9.2 HU (range, 20.7-47 HU) for chromophobe tumors (p = 0.06). Eight clear cell RCCs had attenuation similar to that of water (15.7 ± 2.4 HU; range, 11-18.7 HU). There was no significant difference in calcification or margin among different types of tumors (p = 0.91 and p = 0.55, respectively). Chromophobe tumors were more likely to be homogeneous (p < 0.001). Interobserver agreement was moderate to very good (κ = 0.91 for calcification, κ = 0.55 for margin, and κ = 0.44 for heterogeneity). All eight clear cell RCCs with attenuation similar to that of water were considered heterogeneous by both readers. Irregular margins were identified in three of these eight tumors by reader 1 and four of eight tumors by reader 2. A minority of solid RCCs have attenuation similar to that of water on unenhanced CT. In this study, all such tumors were of the clear cell subtype and qualitatively heterogeneous, suggesting they can be distinguished from simple cysts on unenhanced CT.

Metanephric adenoma: the utility of immunohistochemical and cytogenetic analyses in differential diagnosis, including solid variant papillary renal cell carcinoma and epithelial-predominant nephroblastoma

Metanephric adenoma is a benign renal neoplasm that overlaps in morphology with the solid variant of papillary renal cell carcinoma and epithelial-predominant nephroblastoma. To aid in resolving this differential diagnosis, we investigated the utility of immunohistochemical and molecular analyses in distinguishing between these entities; the first study, to our knowledge, to use a combined approach in analyzing all three tumors. We analyzed 37 tumors originally diagnosed as metanephric adenomas (2 of which we reclassified as papillary renal cell carcinomas), 13 solid variant papillary renal cell carcinomas, and 20 epithelial-predominant nephroblastomas using a combination of immunohistochemistry and fluorescence in situ hybridization (FISH) assessing for trisomy of chromosomes 7 and 17 and loss of Y. Immunohistochemical staining was performed for CK7, AMACR, WT1, and CD57. The combination of CK7–, AMACR–, WT1+, and CD57+ was considered characteristic of metanephric adenoma. Most of the tumors originally diagnosed as metanephric adenomas (31/37) showed the expected staining pattern of metanephric adenoma (CK7−, AMACR–, WT1+, and CD57+). Of the six tumors with discordant immunophenotype, two tumors were reclassified as papillary renal cell carcinoma after cytogenetic workup. It is recommended that all adult cases histologically resembling metanephric adenoma have WT1, CD57, CK7, and AMACR immunohistochemical staining performed. If the staining pattern is characteristic for metanephric adenoma (CK7–, AMACR–, WT1+, and CD57+, including membranous staining), then no other diagnostic tests are indicated. However, if there is a different immunostaining pattern, then we recommend FISH analysis.

MP69-04 NUTRITIONAL SCREENING IS STRONGLY ASSOCIATED WITH OVERALL SURVIVAL IN PATIENTS TREATED WITH TARGETED AGENTS FOR ADVANCED RENAL CELL CARCINOMA

available at http://www.ncbi.nlm.nih.gov/pubmed/26901011 Editorial Comment: This study examined 137 renal masses without fat. All masses were smaller than 4 cm. Patients were scanned during the noncontrast and nephrographic phases (many also underwent corticomedullary imaging). A total of 117 renal cell carcinomas and 20 benign lesions were included. Of the 117 malignant masses 9 (8%) did not reach the 15 HU enhancement threshold on nephrographic imaging and 14 (12%) did not reach the 20 HU threshold. Clear cell, papillary and chromophobe lesions were identified as the hypoenhancing masses. As we closely scrutinize small renal lesions, enhancement is an important indicator of whether a lesion is solid or cystic. Some solid renal cell carcinomas may be hypoenhancing and overlap in the range with renal cysts that may show some artifactual pseudoenhancement. Radiologists must review the morphology of the small hypoenhancing mass, review prior studies and consult the patient electronic radiology jacket to see if other imaging (ultrasound or magnetic resonance) may assist in differentiating the subtle solid hypoenhancing lesion from a simple cyst, complicated cyst or high attenuation cyst.

MP69-11 CARBONIC ANHYDRASE IX ASSAY: A PARADIGM SHIFT IN DIAGNOSIS OF MALIGNANT CYSTIC RENAL LESIONS.

You have accessJournal of UrologyKidney Cancer: Advanced II1 Apr 2015MP69-11 CARBONIC ANHYDRASE IX ASSAY: A PARADIGM SHIFT IN DIAGNOSIS OF MALIGNANT CYSTIC RENAL LESIONS. Himesh Gandhi, Appu Thomas, Balagopal T. Nair, and Vinoth Kumar Lakshmanan Himesh GandhiHimesh Gandhi More articles by this author , Appu ThomasAppu Thomas More articles by this author , Balagopal T. NairBalagopal T. Nair More articles by this author , and Vinoth Kumar LakshmananVinoth Kumar Lakshmanan More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2015.02.2515AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Cystic renal neoplasms are always decided radiologically using Bosniak classification system for renal cysts with many times the histopathology being benign in final report. Carbonic anhydrase IX (CA IX), a known marker for solid clear cell renal cell carcinoma (CCRCC) with good sensitivity and specificity, may be useful for differentiating benign versus malignant renal cystic lesions. The purpose of the study was to demonstrated the usefulness of CAIX in these confusing scenarios and to have a new tool for definitive diagnosis in such cases before contemplating radical surgery. METHODS A total of 22 patients were included in the study prospectively. Twelve patients diagnosed with Complex renal cysts-Bosniak type IIF, III, IV on Contrast-Enhanced Computerized Tomography (CECT) Abdomen and Pelvis undergoing partial/ radical nephrectomy were analysed. Intra-operatively,the aspirates were collected from complex cystic lesions and they were subjected to western blot analysis. Similarly, aspirates were collected from 10 patients with simple renal cysts undergoing surgery for other indications and their apirates were also subjected to western blotting to act as a control. Histopathological examination (HPE)of all operated complex cyst patients was done. Immunohistochemical (IHC) staining and scoring for both intensity and extent of positivity was done on the HPE slides. Scoring was done using a composite Score with score <2 was considered negative for CAIX expression while 2-3 was considerate moderate and > 3 considered strong resp and CA IX expression detected by western blotting and IHC staining were correlated. RESULTS Majority of the cysts in the study population belongs to Bosniak category III (85%). Diagnostic accuracy of the CA IX assay using Western Blotting was 83.33% and correlated with IHC staining with a negative predictive value 100%. Below table shows the correlation between IHC staining and CA IX expression using wetsern blotting. CONCLUSIONS Positive CA IX assay reflects presence of malignancy and those with negative test can be offered an surveillance thus obviating the need for immediate radical surgery as in this era renal preservation should be the main goal. CAIX should be considered a promising molecular marker to differentiate such complex cystic renal tumors (malignant versus benign cysts) and play role in definitive management. Correlation of CA IX expression profile using western blotting with IHC staining in complex cysts aspirates IHC* staining of HPE slides CA IX# positive CA IX # negative Total Positve (C.S.: >/= 2) 10 (83.33%) 2 (16.67%) 12 (100%) Negative (C.S.: < 2) 0 (0) 0 (0) 0 Total 10 (83.33%) 2 (16.67%) 12 (100%) *IHC- Immunohistochemical staining , # CA IX = Carboinc Anhydrase IX , $ C.S. = composite score (Intensity + Extent of staining on IHC). © 2015 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 193Issue 4SApril 2015Page: e870-e871 Advertisement Copyright & Permissions© 2015 by American Urological Association Education and Research, Inc.MetricsAuthor Information Himesh Gandhi More articles by this author Appu Thomas More articles by this author Balagopal T. Nair More articles by this author Vinoth Kumar Lakshmanan More articles by this author Expand All Advertisement Advertisement PDF DownloadLoading ...

204 Nutritional screening is strongly associated with overall survival in patients treated with targeted agents for advanced renal cell carcinoma

available at http://www.ncbi.nlm.nih.gov/pubmed/26901011 Editorial Comment: This study examined 137 renal masses without fat. All masses were smaller than 4 cm. Patients were scanned during the noncontrast and nephrographic phases (many also underwent corticomedullary imaging). A total of 117 renal cell carcinomas and 20 benign lesions were included. Of the 117 malignant masses 9 (8%) did not reach the 15 HU enhancement threshold on nephrographic imaging and 14 (12%) did not reach the 20 HU threshold. Clear cell, papillary and chromophobe lesions were identified as the hypoenhancing masses. As we closely scrutinize small renal lesions, enhancement is an important indicator of whether a lesion is solid or cystic. Some solid renal cell carcinomas may be hypoenhancing and overlap in the range with renal cysts that may show some artifactual pseudoenhancement. Radiologists must review the morphology of the small hypoenhancing mass, review prior studies and consult the patient electronic radiology jacket to see if other imaging (ultrasound or magnetic resonance) may assist in differentiating the subtle solid hypoenhancing lesion from a simple cyst, complicated cyst or high attenuation cyst.

Pseudotumours in chronic kidney disease: Can diffusion-weighted MRI rule out malignancy

ObjectivesTo evaluate whether diffusion-weighted MRI (DW-MRI) can distinguish pseudotumours in chronic kidney disease (CKD pseudotumours) from renal-cell-carcinomas (RCCs) (with or without CKD) and whether it offers additional benefit over conventional MRI. MethodsOne-hundred patients underwent MDCT, MRI and DW-MRI (at b-values of 0 and 500s/mm2) for evaluation of focal renal lesions. Of these, 20 patients with 40 CKD pseudotumours and 36 patients with 40 RCCs were retrospectively analyzed. T1-weighted, T2-weighted, diffusion-weighted images were evaluated, apparent-diffusion-coefficient (ADC) values were compared and receiver-operating-characteristic (ROC) curves were drawn to establish cut-off ADC-values. Results92.5% of CKD pseudotumours remained indeterminate after conventional MRI. On DW-MRI, none of them showed restricted diffusion and thus malignancy could be ruled out in 100% of the lesions. In contrast, all the solid RCCs showed diffusion restriction. Mean ADC-value for CKD pseudotumours was significantly higher than RCCs and surrounding diseased parenchyma [2.50 vs 1.56 (×10−3mm2/s) (P<0.0001) and 2.05 (×10−3mm2/s) (P=0.0001) respectively]. ROC analysis for differentiating CKD pseudotumours and RCC yielded high sensitivity (91.7%) and specificity (100%) for cut-off ADC-value of 2.04 (×10−3mm2/s). ConclusionsCKD pseudotumors usually remain indeterminate on conventional non-contrast MRI. DW-MRI can distinguish CKD pseudotumors from RCCs and offers a non-contrast non-invasive alternative for ruling out malignancy.

Metanephric adenoma and solid variant of papillary renal cell carcinoma: common and distinctive features

To evaluate morphological and immunohistochemical (IHC) features helpful in distinguishing metanephric adenoma (MA) from solid papillary renal cell carcinoma (s-PRCC). We present a detailed study of 21 MA and 23 s-PRCC. The two entities exhibited significant similarities, both being well-circumscribed tumours composed of tightly packed small cells arranged in solid sheets or ill-defined tubules, often presenting glomeruloid bodies, psammoma bodies and dystrophic calcification, and showing overlapping immunoreactivity for S100, CD57 and CK7. Conversely, most MA were non-encapsulated, whereas most s-PRCC showed a thick fibrous pseudocapsule; MA cells had scanty cytoplasm and a high nuclear:cytoplasmic ratio in comparison to s-PRCC, where occasional tumour cells showed abundant cytoplasm and high nuclear grade. Polypoid branching fronds were common in MA, but absent in s-PRCC; multifocality and papillary hyperplasia/adenoma were seen only in s-PRCC. MA were positive for WT1 and negative for EMA and alpha-methylacyl-CoA racemase (AMACR); s-PRCC were positive for EMA and AMACR and negative for WT1. Despite overlapping features, careful morphological and architectural evaluation should result in accurate diagnosis of most MA and s-PRCC. In challenging cases, IHC stains for WT1, EMA and AMACR may help in distinguishing these two entities.

Preoperative decision making for renal cell carcinoma: Cystic morphology in cross-sectional imaging might predict lower malignant potential

ObjectivesSeveral histologic studies showed more favorable oncologic outcome for renal cell carcinoma (RCC) with cystic change. However, there is no prognostic tool to judge on cystic RCC preoperatively. We hypothesized, that cystic morphology in cross-sectional imaging predicts lower malignant potential. Materials and methodsFrom our prospectively conducted oncologic database, we identified 825 patients who underwent surgery for malignant renal tumors between 2001 and 2010. In 348 cases (42%), adequate imaging was available for an independent review by 2 radiologists. We excluded recurrent and synchronous bilateral RCC, familial syndromes, collecting duct carcinoma, and metastases of other origin. For the resulting 319 patients, we compared clinical, pathologic, and survival outcomes. ResultsMedian age was 63 (19–88) years and 220 (69%) patients were male. Median follow-up was 1.7 (0–9.8) years. Of 319 renal masses, 277 (86.8%) were solid and 42 (13.2%) were cystic. In cystic RCC, median tumor diameter was lower (3cm vs. 4cm, P = 0.002) and nephron-sparing surgery was more frequent (69% vs. 41.5%, P = 0.002). None of the patients with cystic RCC and 56 (20.2%) with solid RCC had synchronous systemic disease (P = 0.001). The nuclear grade of cystic RCC was more favorable (P = 0.002). Patients with cystic RCC showed better overall (P = 0.049) and cancer-specific survival (P = 0.027). In a multivariate model, only synchronous metastases, positive R status, and greater tumor diameter were independent risk factors (P≤ 0.03). ConclusionsWe report the first study to show that cystic morphology in cross-sectional imaging might predict RCC with a lower malignant potential. This insight could allow less invasive treatment strategies in selected patients.

637 PREOPERATIVE DECISION-MAKING FOR RENAL CELL CARCINOMA: CYSTIC MORPHOLOGY IN CROSS SECTIONAL IMAGING PREDICTS LOWER MALIGNANT POTENTIAL

You have accessJournal of UrologyKidney Cancer: Evaluation & Staging (I)1 Apr 2013637 PREOPERATIVE DECISION-MAKING FOR RENAL CELL CARCINOMA: CYSTIC MORPHOLOGY IN CROSS SECTIONAL IMAGING PREDICTS LOWER MALIGNANT POTENTIAL Johannes Huber, Alexandra Winkler, Thomas Bruckner, Wilfried Roth, Peter Hallscheidt, Keivan Daneshvar, Markus Hohenfellner, and Sascha Pahernik Johannes HuberJohannes Huber Heidelberg, Germany More articles by this author , Alexandra WinklerAlexandra Winkler Heidelberg, Germany More articles by this author , Thomas BrucknerThomas Bruckner Heidelberg, Germany More articles by this author , Wilfried RothWilfried Roth Heidelberg, Germany More articles by this author , Peter HallscheidtPeter Hallscheidt Heidelberg, Germany More articles by this author , Keivan DaneshvarKeivan Daneshvar Heidelberg, Germany More articles by this author , Markus HohenfellnerMarkus Hohenfellner Heidelberg, Germany More articles by this author , and Sascha PahernikSascha Pahernik Heidelberg, Germany More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2013.02.189AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Several histologic studies showed more favorable oncologic outcome for renal cell carcinoma (RCC) with cystic change. However, there is no prognostic tool to judge on cystic RCC preoperatively. We hypothesized, that cystic morphology in cross sectional imaging predicts lower malignant potential. METHODS From our prospectively conducted oncologic database we identified 825 patients who underwent surgery for RCC from 2001 through 2011. In 348 cases (42%) adequate imaging was available for independent review by two radiologists. We excluded recurrent and synchronous bilateral RCC, familial syndromes, collecting duct carcinoma, and metastases. For the resulting 319 patients we compared clinical, pathological, and survival outcomes. RESULTS Median age was 63 (19-88) years and 220 (69%) patients were male. Median follow-up was 1.7 (0-9.8) years. Of 319 renal masses 277 (86.8%) were solid and 42 (13.2%) were cystic. In cystic RCC median tumor diameter was lower (3 cm vs 4 cm, p=0.002), and nephron-sparing surgery was more frequent (69% vs 41.5%, p=0.002). None of the patients with cystic RCC and 56 (20.2%) with solid RCC had synchronous systemic disease (p=0.001). The nuclear grade of cystic RCC was more favorable (p=0.002). Patients with cystic RCC showed better overall (p=0.049) and cancer-specific survival (p=0.027). In a multivariate model only synchronous metastases, positive R-status, and greater tumor diameter were independent risk factors (p≤0.03). CONCLUSIONS We report the first study to show, that cystic morphology in cross sectional imaging predicts RCC with a lower malignant potential. This insight might allow less invasive treatment strategies in selected patients. © 2013 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 189Issue 4SApril 2013Page: e260 Advertisement Copyright & Permissions© 2013 by American Urological Association Education and Research, Inc.MetricsAuthor Information Johannes Huber Heidelberg, Germany More articles by this author Alexandra Winkler Heidelberg, Germany More articles by this author Thomas Bruckner Heidelberg, Germany More articles by this author Wilfried Roth Heidelberg, Germany More articles by this author Peter Hallscheidt Heidelberg, Germany More articles by this author Keivan Daneshvar Heidelberg, Germany More articles by this author Markus Hohenfellner Heidelberg, Germany More articles by this author Sascha Pahernik Heidelberg, Germany More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Minimal Fat Renal Angiomyolipoma: The Initial Study with Contrast-Enhanced Ultrasonography

We visualized minimal fat renal angiomyolipomas (AMLs) by contrast-enhanced ultrasonography (CEUS). Conventional ultrasound and CEUS images were retrospectively analyzed for solid minimal fat renal AML cases (n = 18) and solid renal cell carcinoma (RCC) cases (n = 105). We compared size, echogenicity and color flow signals with conventional ultrasound, and enhancement patterns with CEUS, in AMLs vs. RCCs. No significant differences in echogenicity and color flow signal existed between AMLs and RCCs using conventional ultrasound. With CEUS, slow centripetal enhancement in the cortical phase (83.3% of AMLs vs. 1.9% of RCCs) and homogeneous peak enhancement (100.0% of AMLs vs. 34.3% of RCCs) were valuable traits for differentiating these tumor types. These two CEUS-determined traits, combined, were differentiating criteria for minimal fat renal AMLs and RCCs; positive and negative predictive values were 100.0% and 97.2%, respectively. Slow centripetal enhancement in the cortical phase and homogeneous enhancement at peak are main features of CEUS-confirmed solid minimal fat renal AML.