Objective To investigate the clinicopathological features and prognosis of chromophobe renal cell carcinoma(ChRCC). Methods The clinical and pathological data of 126 patients with ChRCC treated in Cancer Hospital of Chinese Academy of Medical Sciences were retrospectively analyzed. Results The patients included 64 males and 62 females,with the age of 22-80 years(median of 52 years).The tumor was located on the right side in 70 cases and on the left side in 56 cases.Ultrasound,CT or magnetic resonance imaging(MRI)were performed.Of the 110 cases receiving ultrasound examination,63,23,13,10,and 1 cases showed hypoecho,hyperecho,isoecho,uneven or mixed echo,and dark hypoecho,respectively.Color Doppler flow imaging showed no blood flow signal in 42 cases and low blood flow signal in 60 cases out of 68 cases with blood flow signal.Among the 54 cases receiving CT,50 cases showed equal density or low density and 4 cases showed high density with clear boundary.The enhanced scanning showed mild to moderate uniform or non-uniform reinforcement,mostly below the renal parenchyma,and still showed reinforcement in the delayed period.Among the 97 cases receiving MRI,96 cases showed hypo-or isointense signals and 1 case showed hyperintense signal in T1 weighted images;71 cases showed hyper-or isointense signals and 26 cases showed hypo-or isointense signals in T2 weighted images;93 cases showed hyperintense signals with obvious limited diffusion and 4 cases showed unobvious limited diffusion in diffusion weighted images.Mild to moderate uniform or non-uniform reinforcement was observed in most of the enhanced scans.All the 126 patients underwent surgical treatment,including 64 cases of nephron sparing surgery and 62 cases of radical surgery.Pathological examinations confirmed ChRCC for all the patients,including 91 cases of T1N0M0,15 cases of T2N0M0,and 20 cases of T3N0M0.The immunohistochemical assay demonstrated the positive expression rate of 48.2%(54/112)for CD10,92.3%(96/104)for CD117,8.0%(9/112)for vimentin,85.6%(95/111)for CK7,and 97.6%(83/85)for colloidal iron.Conclusions ChRCC is less common,with low level of malignancy and good prognosis.Since the clinical symptoms of ChRCC are not typical,MRI is an important means of imaging differential diagnosis,and the disease can be confirmed depending on pathological diagnosis.Surgery is the preferred treatment method,and currently there is no standard treatment regimen for metastatic patients.
Adult ; Aged ; Aged, 80 and over ; Carcinoma, Renal Cell/diagnostic imaging* ; Diagnosis, Differential ; Female ; Humans ; Immunohistochemistry ; Kidney Neoplasms/surgery* ; Male ; Middle Aged ; Retrospective Studies ; Young Adult

BACKGROUNDThe difference between renal oncocytomas (RO) and renal clear cell carcinomas (RCCs) presents the greatest diagnostic challenge. The aim of this study was to retrospectively determine if RO and RCCs could be differentiated on computed tomography (CT) images on the basis of their enhancement patterns with a new enhancement correcting method.

METHODSForty-six patients with a solitary renal mass who underwent total or partial nephrectomy were included in this study. Fourteen of those were RO and 32 were RCCs. All patients were examined with contrast-enhanced CT. The pattern and degree of enhancement were evaluated. We selected the area that demonstrated the greatest degree of enhancement of the renal lesion in the corticomedullary nephrographic and excretory phase images. Regions of interest (ROI) were also placed in adjacent normal renal cortex for normalization. We used the values of the normal renal cortex that were measured at the same time as divisors. The ratios of lesion-to-renal cortex enhancement were calculated for all three phases. The Student's t-test and Pearson's Chi-square test were used for statistical analyses.

RESULTSAll RCCs masses showed contrast that appeared to be better enhanced than RO on all contrast-enhanced phases of CT imaging, but there was no significant difference in absolute attenuation values between these two diseases (P > 0.05). The ratio of lesion-to-cortex attenuation in the corticomedullary phase showed significantly different values between RO and RCCs. The degree of contrast enhancement in RCCs was equal to or greater than that of the normal renal cortex, but it was less than that of the normal cortex in RO in the corticomedullary phase. The ratio of lesion-to-cortex attenuation in the corticomedullary phase was higher than the cut off value of 1.0 in most RCCs (84%, 27/32) and lower than 1.0 in most RO (93%, 13/14) (P < 0.05). In the nephrographic phase, the ratio of lesion-to-cortex attenuation was higher than that in the corticomedullary phase in most RO (71%, 10/14), showing a prolonged enhancement pattern; and was lower than that in most RCCs (97%, 31/32), showing an early washout pattern (P < 0.05). In the differentiation of RO from RCCs, the sensitivity was 93%, specificity 84%, positive predictive value 72%, negative predictive value 84%, and accuracy for RO was 87, if the ratio of lesion-to-cortex attenuation in a cortex phase was lower than the cutoff value of 1.0. The sensitivity was 71%, specificity was 97%, positive predictive value was 91%, negative predictive value was 91%, and accuracy for RO was 89%, if the ratio of lesion-to-cortex attenuation in nephrographic phase was higher than that in the corticomedullary phase.

CONCLUSIONSThe ratios of renal lesion-to-cortex attenuation ratios may be helpful in differentiating RO from RCCs.

Adenoma, Oxyphilic ; diagnosis ; diagnostic imaging ; Adult ; Aged ; Carcinoma, Renal Cell ; diagnosis ; diagnostic imaging ; Female ; Humans ; Kidney Neoplasms ; diagnosis ; diagnostic imaging ; Male ; Middle Aged ; Tomography, X-Ray Computed

OBJECTIVETo explore the possibility of predicting the histopathological types of small renal cell carcinoma (RCC) by analyzing the different ways of enhancement with multiphasic multidetector computed tomography (MDCT) of small renal cell carcinomas (diameter≤4 cm).

METHODSCT images of 93 cases, diagnosed as RCC by pathology, were analyzed retrospectively, including 70 clear cell renal cell carcinoma (CCRCC), 13 papillary renal cell carcinoma (PRCC) and 10 chromophobe renal cell carcinoma (CRCC). All of the cases were examined by multiphasic multidetector CT scanning.

RESULTSIn plain scans, 46 CCRCCs were homogeneous, 21 CCRCCs were heterogeneous with low-density area and 3 of them had calcification. CCRCCs were enhanced in contrast scan with a presence of "wash in and wash out" enhancement in general. 11 PRCCs were homogeneous and 2 PRCCs had calcification. Slight-homogeneous enhancement and "delayed enhancement" were present in the PRCCs. Six CRCCs were homogeneous and 2 were calcified, 2 CRCCs were heterogeneous with low-density area. The CRCCs presented as slight or moderate enhancement and 5 CRCCs as homogeneous enhancement, while one CRCC was "spoke-wheel-like enhancement", with a trend of "delayed enhancement". Statistically significant differences were revealed among the actual enhanced CT values, the ratio of enhanced CT value to aorta CT value in the corticomedullary phase, nephrographic phase and excretory phase between the CCRCCs and non-CCRCCs (P<0.001). The analysis of receiver operating characteristic curves (ROC) revealed that when the actual enhanced CT value of tumors in CMP larger than 84.2 HU, the ratio of actual enhanced CT value to aorta CT value at the same phase in CMP larger than 0.315 were used as criteria to diagnose CCRCCs and excluded non-CCRCCs, the diagnostic value was best.

CONCLUSIONSMDCT is of an important significance in the diagnosis and differential diagnosis of small CCRCCs and non-CCRCCs.

Calcinosis ; diagnostic imaging ; Carcinoma, Papillary ; diagnostic imaging ; Carcinoma, Renal Cell ; diagnostic imaging ; Carcinoma, Small Cell ; diagnostic imaging ; Contrast Media ; Diagnosis, Differential ; Humans ; Kidney Neoplasms ; diagnostic imaging ; Multidetector Computed Tomography ; ROC Curve ; Retrospective Studies

OBJECTIVETo study the CT findings of cystic nephroma (CN) and multilocular cystic renal cell carcinoma (MCRCC) and to improve the accuracy of preoperative diagnosis of these two diseases.

METHODSThe CT findings of nine CN cases and 19 MCRCC cases confirmed by pathology were blindly reviewed and compared with their pathological results. Fisher's exact test and independent-samples T test were applied to statistically analyze some of the CT features of the CN and MCRCC lesions.

RESULTSThe thickness of cystic walls and partitions in the nine CN cases ranged from 0.5 to 5 mm. Cystic walls and partitions were slightly thicker in some parts without visible mural nodules. Varying amounts of solid tissue could be found in all the 19 MCRCC tumors, and the cystic walls and partitions were found partially thickened ranging from 3 mm to 13 mm. Eight cases were with mural nodules (nodule diameter: 4.5-16 mm). Nine cases of CN tumors were lobulated and 7 protruded into the renal sinus. Three out of the 19 MCRCC presented shallow lobulation, and 7 tumors protruded into the renal sinus. The CT contrast-enhancement scanning displayed moderate delayed enhancement in the cystic walls and partitions in 8 cases. The enhanced scanning revealed that all the nine cases showed enhancement of the cystic walls and partitions, while 8 cases of them had mild to moderate delayed enhancement. The cystic walls, partitions and nodules were enhanced in 19 MRCC cases, among them 17 cases displayed obvious enhancement in the cortical phase. Among the differences of CT findings between MC and MRCC, the shallow lobulation, protruding into the renal sinus, mural nodules, cystic wall and partition thickness, and net growth in the cortical and nephrographic phase were statistically significantly different (P<0.05 for all).

CONCLUSIONSCT scan can provide significant evidence for CN and MCRCC diagnosis. CN cases usually present relatively thin and even cystic walls and partitions without mural nodules and with shallow lobulation and protruding into the renal sinus. The enhancement is mild to moderate, dynamic and delayed, while the opposite CT findings may indicate a higher possibility of MCRCC.

Adenocarcinoma, Clear Cell ; diagnostic imaging ; Carcinoma, Renal Cell ; diagnostic imaging ; Diagnosis, Differential ; Humans ; Kidney ; diagnostic imaging ; Kidney Diseases, Cystic ; diagnostic imaging ; Kidney Neoplasms ; diagnostic imaging ; Tomography, X-Ray Computed

OBJECTIVETo study the clinical and histopathologic features of metanephric adenoma (MA).

METHODSEight cases of recently diagnosed MA were retrieved from archival file. Immunohistochemical study was carried out. The clinical characteristics, pathologic parameters, differential diagnosis, treatment options and prognosis of MA were analyzed, with literature review.

RESULTSThe patients included 6 females and 2 males. The age of patients ranged from 12 to 70 years (mean=43.6 years). Eight cases were located in renal cortex and showed well-defined borders. Histologically, the tumor was composed of tubules lined by small basophilic cells and embedded in an edematous stroma. Papillary structures and psammoma bodies were focally seen. Immunohistochemical study showed that the tumor cells were positive for PAX2 and vimentin in all the 8 cases. WT-1 was positive in 2 cases, focal and weak in 5 cases, and negative in 1 case. CK-Pan was positive in 3 cases. CK7 staining was mostly negative, with focal and weak positivity only in 1 case. The proliferative index, as highlighted by Ki-67 staining, was less than 2% in 7 cases and focally around 5% in 1 case. The expressions of CK20, CD10, RCC, epithelial membrane antigen, CD56, synaptophysin and chromogranin A were negative. Follow-up information from 7 to 57 months was available in all patients; and none of them developed local recurrence or distant metastasis.

CONCLUSIONSThe diagnosis of MA relies primarily on thorough histologic examination and immunohistochemical study (vimentin and PAX2 positive, WT-1 focally and weakly positive in some cases, and low proliferative index). Correlation with clinical and radiologic findings would also be helpful.

Adenoma ; diagnostic imaging ; metabolism ; pathology ; surgery ; Adolescent ; Adult ; Aged ; Biomarkers, Tumor ; metabolism ; Carcinoma, Renal Cell ; metabolism ; pathology ; Child ; Diagnosis, Differential ; Female ; Follow-Up Studies ; Humans ; Kidney Neoplasms ; diagnostic imaging ; metabolism ; pathology ; surgery ; Male ; Middle Aged ; Nephrectomy ; methods ; PAX2 Transcription Factor ; metabolism ; Tomography, X-Ray Computed ; Vimentin ; metabolism ; WT1 Proteins ; metabolism ; Wilms Tumor ; pathology ; Young Adult

BACKGROUNDThere are relatively few reports focusing on clinical and multi-slice CT (MSCT) imaging findings of mucinous tubular and spindle cell carcinoma (MTSCC). Our study aimed to characterize the clinical and MSCT imaging features of MTSCC.

METHODSThe imaging findings in 17 patients with MTSCC by MSCT were retrospectively studied. MSCT was undertaken to investigate tumor location, size, density, cystic or solid appearance, calcification, capsule sign, enhancement pattern, and retroperitoneal lymph node metastasis.

RESULTSTumors (mean diameter, (3.9 ± 1.7) cm) were solitary (17/17), solid (16/17) with cystic components (5/17), had no calcifications (14/17), had a poorly defined margin (14/17), were centered in the medulla (15/17), compressed the renal pelvis (7/17), and neither lymph node nor distant metastasis was found. The attenuation of MTSCC tumors was equal to that of the renal cortex or medulla on unenhanced CT (32.3 ± 2.6, 36.3 ± 4.6, 33.2 ± 3.9, respectively, P > 0.05), while tumor enhancement after administration of a contrast agent was lower than that of normal renal cortex and medulla during all phases (P < 0.05).

CONCLUSIONMTSCC tends to be a solitary, isodense mass with poorly defined margin arising from the renal medulla with enhancement less than the cortex and medulla during all phases.

Adenocarcinoma, Mucinous ; diagnosis ; diagnostic imaging ; Adult ; Carcinoma ; diagnosis ; diagnostic imaging ; Carcinoma, Renal Cell ; diagnosis ; diagnostic imaging ; Female ; Humans ; Kidney Neoplasms ; diagnosis ; diagnostic imaging ; Male ; Middle Aged ; Radiography

OBJECTIVETo investigate the value of real-time contrast-enhanced ultrasound (CEUS) in the diagnosis and differential diagnosis of renal solid renal lesions (RSLs).

METHODSWe retrospectively analyzed 140 cases of 152 RSLs with a mean diameter 3.1∓1.9 cm. CEUS was performed and the perfusion characteristics were analyzed using contrast pulse sequences (CPS) technique. CEUS findings were compared with biopsy histopathologic findings.

RESULTSA total of 137 malignant lesions (including 127 renal clear cell carcinomas, 8 renal papillary carcinomas and 2 chromophobe cell carcinomas) and 15 benign lesions (13 angiomyolipomas and 2 renal oncocytomas) were detected. Of the 137 malignant lesions, 98 (71.5%) showed contrast agent fast perfusion and hyper-enhancement or iso-enhancement in cortical phase, 104 (75.9%) showed hypo-enhancement in later corticalmedullary and late phase, and 125 (91.2%) showed rim-like enhancement. Tumors with a diameter ≤2 cm presented with homogeneous enhancement, and those ranging from 2 to 4 cm showed heterogeneous enhancement with a honeycomb feature; tumors greater than 4 cm featured heterogeneous enhancement with large no-enhancement necrotic areas. Of the benign lesions, 13 angiomyolipomas and 2 renal oncocytomas showed slow wash-in and slow wash-out mode. The diagnostic specificity, accuracy and positive predictive value of CEUS for RSLs were 94.9%, 96.1%, and 73.7%, as compared to 72.3%, 71.1%, and 19.1% with conventional US, respectively (P<0.001). The sensitivity and negative predictive value of CEUS were 93.3% and 99.2%, respectively, significantly higher than those of conventional US (60% and 94.3%, P=0.084, and 0.062, respectively).

CONCLUSIONReal-time CEUS can provide valuable information for improving the diagnosis and differential diagnosis of RSLs.

Adenoma, Oxyphilic ; diagnostic imaging ; Carcinoma, Renal Cell ; diagnostic imaging ; Contrast Media ; Diagnosis, Differential ; Humans ; Kidney Diseases ; diagnostic imaging ; Kidney Neoplasms ; diagnostic imaging ; Retrospective Studies ; Sensitivity and Specificity ; Ultrasonography

OBJECTIVETo investigate the value of contrast enhanced ultrasound (CEUS) imaging in the differential diagnosis between benign and malignant renal neoplasms.

METHODSTwo hundred and forty-five cases of renal space-occupying lesions confirmed by biopsy or surgical pathology were included in this study. The CEUS features of the renal space-occupying lesions, i.e., the enhancement degree, homogeneity of enhancement, washing-in and washing-out time and enhancement pattern, were retrospectively analyzed.

RESULTSThere were 210 cases of malignant renal tumors and 35 cases of benign lesions. The CEUS modes of the malignant renal tumors included "quick in and quick out" 82 cases, "quick in and slow out" 64 cases, "slow in and quick out" 18 cases and "slow in and slow out" 46 cases; good enhancement 150 cases (71.4%) and inhomogeneous enhancement 180 cases (85.7%).Both the contrast agent filling defect area and solid component enhancement of solid-cystic tumors were important features of malignant renal tumors. In the 35 cases of benign lesions,the CEUS modes included "quick in and quick out" 4 cases, "quick in and slow out" 8 cases, "slow in and quick out" 10 cases and "slow in and slow out" 13 cases. Most of the benign tumors showed low enhancement 51.4% (18/35) and inhomogeneous enhancement 54.3% (19/35). There were significant differences between the malignant and benign renal neoplasms in CEUS mode, degree of enhancement and homogeneity of enhancement (P < 0.05), and in time of increasing, peak time, peak intensity and peak intensity ratio (P < 0.05). The accuracy rates of contrast-enhanced ultrasound for diagnosis of benign and malignant tumors were 77.1% and 83.8%, respectively, while the two-dimensional ultrasound diagnosis of benign and malignant tumors were 68.6% and 76.7%, respectively, with a significant difference (P < 0.05).

CONCLUSIONSCEUS may provide more information to improve the diagnostic accuracy for renal neoplasms, and may play important role in differential diagnosis between benign and malignant renal lesions.

Adenoma ; diagnostic imaging ; Adult ; Aged ; Carcinoma, Medullary ; diagnostic imaging ; Carcinoma, Renal Cell ; diagnostic imaging ; Contrast Media ; Diagnosis, Differential ; Echocardiography, Doppler, Color ; Female ; Hamartoma ; diagnostic imaging ; Humans ; Kidney Diseases ; diagnostic imaging ; Kidney Neoplasms ; diagnostic imaging ; Male ; Middle Aged ; Nephritis ; diagnostic imaging ; Retrospective Studies ; Young Adult

OBJECTIVETo investigate the clinicopathological characteristics of sporadic renal hemangioblastoma.

METHODSTwo cases of sporadic renal hemangioblastoma were studied by histological and immunohistochemical staining, along with review of the literature.

RESULTSBoth cases were presented with a renal mass during annual physical examination with an age of 40 and 45 years, respectively. The lesions located in the middle portion of the kidney with a sharp tumor border. Histopathologically, the tumors were characterized by two major components: capillary and stromal cells. Immunohistochemically, the stromal cells were positive for vimentin, NSE, S-100 protein and inhibin-α, and negative for CK, HMB45, Melan A, EMA, CD56 and syn. Both tumors showed a very low level of Ki-67 labeling. The endothelial cells were positive for CD34.

CONCLUSIONSporadic renal hemangioblastoma is a rare benign neoplasm, the diagnosis of which is based on the characteristic follicular architecture and an exclusion of other carcinomas of the kidney.

Adult ; Angiomyolipoma ; metabolism ; pathology ; Antigens, CD34 ; metabolism ; Carcinoma, Renal Cell ; metabolism ; pathology ; Diagnosis, Differential ; Female ; Follow-Up Studies ; Hemangioblastoma ; diagnostic imaging ; metabolism ; pathology ; surgery ; Humans ; Immunohistochemistry ; Inhibins ; metabolism ; Kidney Neoplasms ; diagnostic imaging ; metabolism ; pathology ; surgery ; Male ; Middle Aged ; Nephrectomy ; Phosphopyruvate Hydratase ; metabolism ; S100 Proteins ; metabolism ; Tomography, X-Ray Computed ; methods ; Vimentin ; metabolism

PURPOSE: A morphologic contour method for assessing an exophytic renal mass as benign versus malignant on the basis of the shape of the interface with the renal parenchyma was recently developed. We investigated the usefulness of this morphologic contour method for predicting angiomyolipoma (AML) in patients who underwent partial nephrectomy for small renal masses (SRMs). MATERIALS AND METHODS: From January 2004 to March 2013, among 197 patients who underwent partial nephrectomy for suspicious renal cell carcinoma (RCC), the medical records of 153 patients with tumors (AML or RCC) < or =3 cm in diameter were retrospectively reviewed. Patient characteristics including age, gender, type of surgery, size and location of tumor, pathologic results, and specific findings of the imaging study ("ice-cream cone" shape) were compared between the AML and RCC groups. RESULTS: AML was diagnosed in 18 patients and RCC was diagnosed in 135 patients. Gender (p=0.001), tumor size (p=0.032), and presence of the ice-cream cone shape (p=0.001) showed statistically significant differences between the AML group and the RCC group. In the multivariate logistic regression analysis, female gender (odds ratio [OR], 5.20; 95% confidence interval [CI], 1.45 to 18.57; p=0.011), tumor size (OR, 0.34; 95% CI, 0.12 to 0.92; p=0.034), and presence of the ice-cream cone shape (OR, 18.12; 95% CI, 4.97 to 66.06; p=0.001) were predictors of AML. CONCLUSIONS: This study confirmed a high incidence of AML in females. Also, the ice-cream cone shape and small tumor size were significant predictors of AML in SRMs. These finding could be beneficial for counseling patients with SRMs.
Angiomyolipoma ; Carcinoma, Renal Cell ; Counseling ; Diagnostic Imaging ; Female ; Humans ; Incidence ; Kidney ; Logistic Models ; Medical Records ; Nephrectomy ; Retrospective Studies