Untargeted contrast-enhanced ultrasound versus contrast-enhanced computed tomography: a differential diagnostic performance (DDP) study for kidney lesions

OBJECTIVES: Histopathology is the 'gold standard' for diagnosing renal cell carcinoma but is limited by sample size. Contrast-enhanced ultrasound can differentiate malignant and benign lesions, but the Chinese guidelines on the management of renal cell carcinoma do not include this method. The purpose of this study was to compare the diagnostic parameters of contrast-enhanced ultrasound against those of contrast-enhanced computed tomography for detecting kidney lesions, with histopathology considered the reference standard. METHODS: Patients with suspected kidney lesions from prior grayscale ultrasonography and computed tomography were included in the analysis (n=191). The contrast-enhanced ultrasound, contrast-enhanced computed tomography, and histopathology data were collected and analyzed. A solid, enhanced mass was considered a malignant lesion, and an unenhanced mass or cyst was considered a benign lesion. The Bosniak criteria were used to characterize the lesions. RESULTS: Contrast-enhanced ultrasound and contrast-enhanced computed tomography both detected that 151 patients had malignant tumors and 40 patients had benign tumors. No significant differences in the tumors and their subtypes were reported between contrast-enhanced ultrasound and histopathology (p=0.804). Chromophobe renal cell carcinoma was detected through contrast-enhanced computed tomography (n=1), but no such finding was reported by contrast-enhanced ultrasound. A total of 35 cases of papillary renal cell carcinoma were reported through contrast-enhanced ultrasound while 32 were reported through histopathology. CONCLUSIONS: Contrast-enhanced ultrasound might be safe and as accurate as histopathology in diagnosing kidney lesions, especially renal cell carcinoma. Additionally, this study provides additional information over histopathology and has an excellent safety profile. Level of evidence: III.

A Retrospective Study of Histopathology and Clinical Correlation of Renal Cell Carcinoma in a Tertiary Medical College, India

Background: The study was conducted to understand the clinical solution of renal cell carcinoma. Correlation was done by clinical presentation with radiological features and histopathology of renal cell carcinoma. The stress upon to understand the necessity for a team-approach between Clinician, Radiologist and Pathologist and vice versa is emphasized. Aim: Histopathology and Clinical Correlation of Renal cell carcinoma. Methods: The total number of renal tumours studied during the 8 years period was 45 cases among which 25 cases were diagnosed by histopathology as various types of renal cell carcinoma conclusively. This is a retrospective study of renal tumours, diagnosed by histopathology as various types of renal cell carcinoma. All the relevant clinical data of the patients were searched from the ward records. The various Radiological features were collected. Results: The total number of renal tumours studied during the 8 years period was 45 cases among which 25 cases were diagnosed by histopathology as various types of renal cell carcinoma conclusively. MRI provides molecular information with regard to renal cell carcinoma and potentially aid in biopsy planning. The total cases reported in the department is twenty five vases out of which sixteen cases are attending follow up after 3 years. Conclusion: The Fuhrman grading of renal cell carcinoma correlated grading of renal cell carcinoma. Preoperative radiological classification can be used as a supplement to the histopathological grading. Renal cell carcinoma needs correlation between Radiologist, Pathologist and Clinician.

Contrast-enhanced CT findings of papillary renal cell carcinoma and its subtypes and chromophobe renal cell carcinoma / 实用放射学杂志

Objective To investigate the enhanced CT features of papillary renal cell carcinoma (PRCC)and its subtypes (PRCC-Ⅰ, PRCC-Ⅱ)and chromophobe renal cell carcinoma(CRCC).Methods The CT features of 30 tumors with pathologically proved PRCC and CRCC were analyzed retrospectively,including location,size,enhanced types,calcification and necrosis etc.The differences in the CT features among PRCC and its subtypes and CRCC were evaluated.Results 1 2 cases of PRCC with single lesion (7 in the right kidney and 5 in the left)were shown;1 case was multifocal PRCC with 1 lesion in the right kidney and 2 lesions in the left.1 5 cases of CRCC were single lesion(9 in the right kidney and 6 in the left).The medium tumor maximum size of CRCC was larger than that of PRCC,and the PRCC-Ⅰ tumors tended to be smaller than PRCC-Ⅱ ones.53% of the PRCC had heterogeneous enhancement,and all calcification and necrosis were found in PRCC-Ⅱ lesions.Of all the CRCC,27% had uniform enhancement,20% had calcification and 40% had necrosis or central scar.There was no significant difference between PRCC and its subtypes and CRCC in location, maximum size,heterogeneity,calcification,necrosis and central scar.The degree of enhancement of CRCC(89.53 HU)was significantly greater than that of PRCC(66.60 HU),PRCC-Ⅰ(71.75 HU)and PRCC-Ⅱ(64.73 HU)in the cortical phase(P<0.05).The enhancement peak in the nephrographic phase was CRCC,PRCC-Ⅰ,PRCC and PRCC-Ⅱ from high to low in turn,which were all higher than that in cortical phase.In the excretory phase,the enhancement of all lesions was declined.Conclusion Contrast-enhanced CT is of certain value in the differential diagnosis among PRCC and its subtypes and CRCC.The enhancement degree of CRCC in the cortical phase is significantly greater than that of PRCC and its subtypes.The enhancement peak of PRCC and its subtypes and CRCC appears in the nephrographic phase.

Local lymphatic metastasis for chromophobe renal cell carcinoma in a child after nephron-sparing surgery:a case report and literature review / 中华泌尿外科杂志

Objective To discuss the lymph node metastasis of chromophobe renal cell carcinoma (chRCC) in children.Methods One case of chRCC was reported.A eleven-year-old boy was admitted to our hospital on November 2,2017 and presented gross hematuria 4 weeks.No mass was palpable in the abdomen and he felt tenderness in the left back.The ultrasound showed a solid mass in the lower pole of the left kidney.There were a lot of tortuous blood vessels in the tumor.Contrast enhanced CT suggested a mass of 4.5 cm × 6.3 cm × 4.9 cm.The left renal artery and vein were thickened.There was no enlarged lymph nodes were seen in both examinassions.During the operation,the tumor was located in the lower pole of the kidney.The frozen section diagnosis was benign renal tumor.Nephron-sparing surgery was performed.Results The pathology showed that the tumor cells had well-defined cell borders and characteristic perinuclear halos surrounded by eosinophilic cytoplasm that was positive for Hale's colloidal iron stain.Immunohistochemical studies were positive for EMA (+),Ki-67 (5％ +),CK19 (+),CK (+),CD10 (+),CD117(+),CD56(+).Fluorescence in situ hybridization showed absence of TFE3 protein,a strong immune marker of Xp11.2/TFE renal cell carcinoma.1 year after the operation,contrastenhancement magnetic resonance showed long T1 signal near the left renal hilum and the mass showed slight enhancement.ChRCC with regional lymph node metastasis hereby was considered.Intraoperatively,an approximately 2.5 cm × 2.0 cm × 2.0 cm mass was seen near the the left renal hilum.The tumor did not involve left kidney,abdominal aorta and inferior vena cava.The mass was completely removed and introoperative fast-frozen pathology revealed chRCC.Nephron-sparing surgery was performed.Postoperative pathology report chRCC local lymph node metastasis.Follow-up at six months after resection,there was no recurrence or metastatic disease identified.Conclusions chRCC is rare in children and clinical stage is low with a good prognosis.Local recurrence and distant metastasis is rare.

Seeding Metastasis of Chromophobe Renal Cell Carcinoma after Robot-Assisted Laparoscopic Partial Nephrectomy

Chromophobe renal cell carcinoma (RCC) is an uncommon subtype of RCC having a better prognosis than clear cell RCC. Although there are several reports of seeding metastasis of RCC after biopsy, seeding metastasis of chromophobe RCC after surgical resection has seldom been reported. Here, we describe a case of multiple seeding metastases in the abdomen and pelvis 78 months after robot-assisted laparoscopic partial nephrectomy, without prior history of biopsy for chromophobe RCC in the right kidney. As magnetic resonance imaging (MRI) of the pelvic mass showed a similar appearance to the primary renal mass and displayed separate margins with the rectum and prostate gland, we were able to make a diagnosis before pathologic confirmation.

Seeding Metastasis of Chromophobe Renal Cell Carcinoma after Robot-Assisted Laparoscopic Partial Nephrectomy

Chromophobe renal cell carcinoma (RCC) is an uncommon subtype of RCC having a better prognosis than clear cell RCC. Although there are several reports of seeding metastasis of RCC after biopsy, seeding metastasis of chromophobe RCC after surgical resection has seldom been reported. Here, we describe a case of multiple seeding metastases in the abdomen and pelvis 78 months after robot-assisted laparoscopic partial nephrectomy, without prior history of biopsy for chromophobe RCC in the right kidney. As magnetic resonance imaging (MRI) of the pelvic mass showed a similar appearance to the primary renal mass and displayed separate margins with the rectum and prostate gland, we were able to make a diagnosis before pathologic confirmation.

MRI findings of chromophobe renal cell carcinoma and literature review / 实用放射学杂志

Objective To evaluate the diagnostic value and limitation of MRI for chromophobe renal cell carcinoma.Methods MRI features of 5 cases with pathology proved chromophobe renal cell carcinoma were analyzed retrospectively.Results All tumors showed homogenous isoin-tensity or slightly hypointensity on T1 weighted images and isointensity or slightly hyperintensity on T2 weighted images.Slightly hyperintensity were showed on DWI images,the mean ADC value of tumors was 1.42×10-3 mm2/s.On the contrast enhanced images,all the mass showed slight to moderate enhancement ,1 case had spoke-wheel-like enhancement,1 case showed flowed out blood vessels in the tumor.Conclusion The preoperative diagnosis is difficult for chromophobe renal cell carcinoma,MRI is a valuable method which could provide useful information for qualitative diagnosis.

Differentiation of Chromophobe Renal Cell Carcinoma and Clear Cell Renal Cell Carcinoma by Using Helical CT / 영남의대학술지

BACKGROUND: The purpose of this study was to differentiate chromophobe renal cell carcinoma and clear cell renal cell carcinoma on helical CT. METHODS: The CT images of 9 patients histopathologically proven to have chromophobe renal cell carcinoma and 20 patients with clear cell renal cell carcinoma were reviewed. The tumor sizes, margins, enhancement degrees and patterns, presence or absence of calcification, and tumor spread patterns (including perinephric changes, venous invasion, lymphadenopathy, and distant metastasis) were compared. RESULTS: All the chromophobe renal cell carcinomas showed well-demarcated margins. Thechromophobe renal cell carcinomas showed milder enhancements than the clear cell renal cell carcinomas. The sensitivity and specificity for differentiating the chromophobe renal cell carcinoma from the clear cell renal cell carcinoma were 100 and 88%, respectively, when 101 Hounsfield units was used as the cut-off value in the corticomedullary phase, and 95 and 100% when a less-than-three-time enhancement change was used as a cut-off value in the corticomedullary phase (p0.05). CONCLUSION: The CT findings of the chromophobe renal cell carcinomascompared to those of the clear cell renal cell carcinomas showed that there were mild enhancements in the corticomedullary phase, homogeneous enhancements, and well-demarcated margins.

Claudin-7 is Highly Expressed in Chromophobe Renal Cell Carcinoma and Renal Oncocytoma

Claudin-7 has recently been suggested to be a distal nephron marker. We tested the possibility that expression of claudin-7 could be used as a marker of renal tumors originating from the distal nephron. We examined the immunohistochemical expression of claudin-7 and parvalbumin in 239 renal tumors, including 179 clear cell renal cell carcinoma (RCC)s, 29 papillary RCCs, 20 chromophobe RCCs, and 11 renal oncocytomas. In addition, the methylation specific-PCR (MSP) of claudin-7 was performed. Claudin-7 and parvalbumin immunostains were positive in 3.4%, 7.8% of clear cell RCCs, 34.5%, 31.0% of papillary RCCs, 95.0%, 80.0% of chromophobe RCCs, and 72.7%, 81.8% of renal oncocytomas, respectively. The sensitivity and specificity of claudin-7 in diagnosing chromophobe RCC among subtypes of RCC were 95.0% and 92.3%. Those of parvalbumin were 80.0% and 88.9%. The expression pattern of claudin-7 was mostly diffuse in chromophobe RCC and was either focal or diffuse in oncocytoma. All of the cases examined in the MSP revealed the presence of unmethylated promoter of claudin-7 without regard to claudin-7 immunoreactivity. Hypermethylation of the promoter might not be the underlying mechanism for loss of its expression in RCC. Claudin-7 can be used as a useful diagnostic marker in diagnosing chromophobe RCC and oncocytoma.