Angiomyolipoma (AML) is a rare benign mesenchymal tumor in the liver, which is composed of blood vessels, smooth muscle, and adipose cells. The proportion of each component varies, making a diagnosis difficult. This paper reports a case of AML in the liver without adipose tissue, mimicking a hepatocellular carcinoma (HCC), which was diagnosed by a surgical tissue biopsy. A 65-year-old woman was admitted for an evaluation of a hepatic mass that had been detected by ultrasonography. The serologic markers of viral hepatitis B and C were negative. The liver function tests and alpha fetoprotein level were within the normal limits. Magnetic resonance imaging revealed a 1.9 cm sized mass in segment 6 of the liver with early arterial enhancement and washout on the delayed phase accompanied by a rim-like enhancement, which is similar to the imaging findings of HCC. A frozen section examination during surgery indicated a hepatocellular neoplasm and suggested the possibility of HCC. On the other hand, the final pathologic diagnosis was epithelioid myoid type of AML with no adipose tissue component. The tumor cells were positive for human melanocyte B-45 and negative for cytokeratin and hepatocyte paraffin 1. This paper reports a very rare case of AML without adipose tissue in the liver mimicking HCC that was diagnosed by a surgical tissue biopsy.
Adipose Tissue ; Aged ; alpha-Fetoproteins ; Angiomyolipoma ; Biopsy ; Blood Vessels ; Carcinoma, Hepatocellular ; Diagnosis ; Female ; Frozen Sections ; Hand ; Hepatitis B ; Hepatocytes ; Humans ; Keratins ; Liver Function Tests ; Liver ; Magnetic Resonance Imaging ; Melanocytes ; Muscle, Smooth ; Paraffin ; Ultrasonography

The prevalence of small renal masses (SRM) has risen, paralleling the increased usage of cross-sectional imaging. A large proportion of these SRMs are not malignant, and do not require invasive treatment such as nephrectomy. Therefore, differentation between early renal cell carcinoma (RCC) and benign SRM is critical to achieve proper management. This article reviews the radiological features of benign SRMs, with focus on two of the most common benign entities, angiomyolipoma and oncocytoma, in terms of their common imaging findings and differential features from RCC. Furthermore, the role of percutaneous biopsy is discussed as imaging is yet imperfect, therefore necessitating biopsy in certain circumstances to confirm the benignity of SRMs.
Abdominal Fat/pathology ; Adenoma, Oxyphilic/diagnosis/radiography/ultrasonography ; Angiomyolipoma/diagnosis/radiography/ultrasonography ; Carcinoma, Renal Cell/*diagnosis/radiography/ultrasonography ; Diagnosis, Differential ; Humans ; Kidney Neoplasms/*diagnosis/*radiography/ultrasonography ; Leiomyoma/diagnosis/radiography/ultrasonography

OBJECTIVE: To evaluate the value of enhancement features and quantitative parameters of contrast-enhanced ultrasonography (CEUS) in differentiating solid hypoechoic renal angiomyolipomas (AMLs) from clear cell renal cell carcinomas (ccRCCs). MATERIALS AND METHODS: We analyzed the enhancement features and quantitative parameters of CEUS in 174 hypoechoic renal masses (32 AMLs and 142 ccRCCs) included in the study. RESULTS: Centripetal enhancement pattern was more common in AMLs than in ccRCCs on CEUS (71.9% vs. 23.2%, p < 0.001). At peak enhancement, all AMLs showed homogeneous enhancement (100% in AML, 27.5% in ccRCCs; p < 0.001). Quantitative analysis showed no significant difference between rise time and time to peak. Tumor-to-cortex (TOC) enhancement ratio in AMLs was significantly lower than that in ccRCCs (p < 0.001). The criteria of centripetal enhancement and homogeneous peak enhancement together with TOC ratio < 91.0% used to differentiate hypoechoic AMLs from ccRCCs resulted in a sensitivity and specificity of 68.9% and 95.8%, respectively. CONCLUSION: Both qualitative and quantitative analysis with CEUS are valuable in the differential diagnosis of hypoechoic renal AMLs from ccRCCs.
Adult ; Aged ; Angiomyolipoma/*diagnosis/pathology/*ultrasonography ; Carcinoma, Renal Cell/*diagnosis/pathology/*ultrasonography ; Contrast Media ; Diagnosis, Differential ; Female ; Humans ; Kidney Neoplasms/diagnosis/pathology/*ultrasonography ; Language ; Lipoma/ultrasonography ; Male ; Middle Aged ; Sensitivity and Specificity

PURPOSE: Ultrasound (US) is highly sensitive in the detection of renal masses. However, it may not be able to differentiate benign and malignant lesions in smaller masses. The purpose of this study was to determine the diagnostic efficacy of contrast-enhanced ultrasound (CEUS) for small renal masses. MATERIALS AND METHODS: From January 2011 to December 2013, a total of 85 patients underwent CEUS for evaluation of renal masses. Of these patients, CEUS findings were retrospectively analyzed for small renal cell carcinoma (RCC) cases (n=38) and angiomyolipoma (AML) cases (n=11). The tumor echogenicity and enhancement patterns and degrees were evaluated. The diagnostic efficacy of CEUS in differentiating the two diseases was compared. RESULTS: On CEUS, the findings of diffuse heterogeneous enhancement (observed in 78.9% of RCCs and 27.3% of AMLs, p=0.003), washout from hyperenhancement or iso-enhancement to hypoenhancement in late phase (73.7% of RCCs and 18.2% of AMLs, p=0.001), and perilesional rim-like enhancement (57.9% of RCCs and 9.1% of AMLs, p=0.006) were significantly different between AML and RCC cases. The corresponding sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 86.8% (33/38), 63.6% (7/11), 89.2% (33/37), 58.3% (7/12), and 81.6% (40/49), respectively. CONCLUSIONS: Our results suggest that the characteristic CEUS features could have diagnostic value in the evaluation of small renal mass. CEUS showed a higher diagnostic efficacy than conventional US for differentiating RCC and AML.
Adult ; Aged ; Aged, 80 and over ; Angiomyolipoma/*ultrasonography ; Carcinoma, Renal Cell/*ultrasonography ; Contrast Media/diagnostic use ; Diagnosis, Differential ; Female ; Humans ; Kidney Neoplasms/*ultrasonography ; Male ; Middle Aged ; Reproducibility of Results ; Retrospective Studies ; Sensitivity and Specificity ; Sulfur Hexafluoride/diagnostic use ; Ultrasonography/*methods

PURPOSE: Ultrasound (US) is highly sensitive in the detection of renal masses. However, it may not be able to differentiate benign and malignant lesions in smaller masses. The purpose of this study was to determine the diagnostic efficacy of contrast-enhanced ultrasound (CEUS) for small renal masses. MATERIALS AND METHODS: From January 2011 to December 2013, a total of 85 patients underwent CEUS for evaluation of renal masses. Of these patients, CEUS findings were retrospectively analyzed for small renal cell carcinoma (RCC) cases (n=38) and angiomyolipoma (AML) cases (n=11). The tumor echogenicity and enhancement patterns and degrees were evaluated. The diagnostic efficacy of CEUS in differentiating the two diseases was compared. RESULTS: On CEUS, the findings of diffuse heterogeneous enhancement (observed in 78.9% of RCCs and 27.3% of AMLs, p=0.003), washout from hyperenhancement or iso-enhancement to hypoenhancement in late phase (73.7% of RCCs and 18.2% of AMLs, p=0.001), and perilesional rim-like enhancement (57.9% of RCCs and 9.1% of AMLs, p=0.006) were significantly different between AML and RCC cases. The corresponding sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 86.8% (33/38), 63.6% (7/11), 89.2% (33/37), 58.3% (7/12), and 81.6% (40/49), respectively. CONCLUSIONS: Our results suggest that the characteristic CEUS features could have diagnostic value in the evaluation of small renal mass. CEUS showed a higher diagnostic efficacy than conventional US for differentiating RCC and AML.
Adult ; Aged ; Aged, 80 and over ; Angiomyolipoma/*ultrasonography ; Carcinoma, Renal Cell/*ultrasonography ; Contrast Media/diagnostic use ; Diagnosis, Differential ; Female ; Humans ; Kidney Neoplasms/*ultrasonography ; Male ; Middle Aged ; Reproducibility of Results ; Retrospective Studies ; Sensitivity and Specificity ; Sulfur Hexafluoride/diagnostic use ; Ultrasonography/*methods

OBJECTIVETo investigate the sonographic and computed tomography (CT) features of hepatic angiomyolipoma (HAML).

METHODSSonographic and CT findings were analyzed in 12 patients (9 females and 3 males) with pathologically proved HAML. The size, margin, location, gray scale, and color Doppler flow imaging characteristics were observed.

RESULTSHAML was located correctly with ultrasound in all patients. The sonographic features of 12 HAML included regular shape, clear margin, and three type of echoes including homogeneous hyperechoes (n=5), heterogeneous internal echoes (n=5), or homogeneous hypoechoes (n=2). The arterial flow signal was detected in two HAML. The CT findings included adipose density (n=3), soft tissue density (n=3), and mixed density (n=6). The sonographic and CT findings were correlated with the composition and distribution of fat, vessels, and smooth muscle tissue.

CONCLUSIONSFatty tissues within HAML shows typical imaging findings. The ultrasonographic and CT have their own advantages in detecting the fatty tissue inside HAML, and therefore a combination of these two techniques may increase the diagnostic accuracy of HAML.

Adult ; Aged ; Angiomyolipoma ; diagnostic imaging ; Female ; Humans ; Liver Neoplasms ; diagnostic imaging ; Male ; Middle Aged ; Retrospective Studies ; Tomography, X-Ray Computed ; Ultrasonography

PURPOSE: The renal manifestations of tuberous sclerosis complex (TSC) are remarkably diverse, including polycystic kidney disease, simple renal cysts, renal cell carcinomas, and angiomyolipomas. All of these occur in children as well as adults in TSC. Angiomyolipomas, which can cause spontaneous life-threatening hemorrhages, are by far the most prevalent and the greatest source of morbidity. Here, we will address our experience, adding to the literature on pediatric patients with TSC requiring evaluation and treatment for renal manifestations. METHODS: A retrospective analysis was made on 19 patients in whom TSC was diagnosed between May 2001 and Oct. 2005 at Severance Hospital. All patients had clinical diagnoses of TSC as defined by the 1998 tuberous sclerosis complex consensus conference. RESULTS: The patients consisted of 13 boys and 6 girls with a mean age of 7.3 years (range 1 to 22). The renal disease associated with TSC included angiomyolipoma in nine patients (47.4 percent), renal simple cyst in one (5.3 percent), hydronephrosis in one (5.3 percent) patient. Eight patients (42.1 percent) presented with normal kidney contours at abdominal ultrasonography. One patient underwent renal replacement therapy due to chronic renal insufficiency after nephrectomy. Hemorrhage from angiomyolipoma was not detected. CONCLUSION: In our review of 19 cases of TSC, renal manifestations are reported in 57.9 percent of patients. Asymptomatic angiomyolipoma associated with TSC grow gradually, although severe hemorrhages are rare. So patients with TSC should be followed up with serial computerized tomography or abdominal ultrasonography. And also, renal function should be monitored conservatively.
Adult ; Angiomyolipoma ; Carcinoma, Renal Cell ; Child ; Consensus ; Diagnosis ; Female ; Hemorrhage ; Humans ; Hydronephrosis ; Kidney ; Kidney Failure, Chronic ; Nephrectomy ; Polycystic Kidney Diseases ; Renal Insufficiency, Chronic ; Renal Replacement Therapy ; Retrospective Studies ; Tuberous Sclerosis* ; Ultrasonography

OBJECTIVETo study the diagnosis and management of renal angiomyolipoma (RAML), and to identify risk factors affecting spontaneous angiomyolipoma rupture.

METHODSThe data of 68 patients with RAML from 1989 to 2002 were retrospectively reviewed. These patients were divided in two groups on the basis of tumor size, 35 patients in group A ( 4 cm).

RESULTSSeven patients were identified by image-guided percutaneous biopsy, and no major complications was noted. Sixteen patients with RAML were examined with angiography and 9 of 16 patients had got spontaneous rupture. 41.2% of patients were symptomatic, 4 cases (11.4%) in group A and 24 (72.7%) cases in group B (P < 0.01). There were significant differences in mean tumor size (11.6 cm +/- 5.1 cm vs 5.3 cm +/- 2.9 cm, P < 0.01) and mean aneurysm size (13.6 mm +/- 5.8 mm vs 2.6 mm +/- 3.0 mm, P < 0.01) between 9 cases of the ruptured tumor and 59 cases of unruptured tumor, 9 cases of the ruptured and 7 cases of unruptured tumor with angiography, respectively. Treatment consisted of conservative observation in 10 patients (no radiographic changes during the follow-up of 2 - 7 years); partial nephrectomy in 14 patients, tumor enucleation in 30 patients, total nephrectomy in 14 and posterior laparoscopic nephrectomy in 3 (no recurrence and complication correlation to operation during the follow-up of 2 - 144 months).

CONCLUSIONSIt is an important role that percutaneous biopsy guided by ultrasonography or computerized tomography performs in managing suspicious and/or indeterminate RAML. A higher probability of rupture is related to tumor and/or aneurysms size. Nephron-sparing surgery is the first choice for surgical treatment of RAML.

Adolescent ; Aged ; Angiomyolipoma ; diagnosis ; pathology ; therapy ; Biopsy, Needle ; Female ; Follow-Up Studies ; Humans ; Kidney Neoplasms ; diagnosis ; pathology ; therapy ; Male ; Middle Aged ; Nephrectomy ; methods ; Rupture, Spontaneous ; Tomography, X-Ray Computed ; Ultrasonography, Interventional

Spontaneous rupture of the kidney, Wonderlich syndrome, is a rare event but potentially life-threatening condition. The most comman causes are clear cell carcinoma, benign angiomyolipoma and vascular disease. Among this event, acute pyelonephritis is a very unusual cause. A 67-year-old diabetic woman was admitted with high fever and left flank pain due to acute pyelonephritis. She had uterine prolapse for 10 years with both renal hydronephrosis before this event. Abdominal ultrasonography and CT scan showed fluid collection around left kidney with a rupture of renal parenchyme at lower pole. The renal angiography showed displaced capsular artery due to subcapsular hematoma and decreased blood flow at lower pole. The percutaneous needle aspiration revealed blood collection around left kidney, which confirmed spontaneous rupture of the kidney. We report this case with a review of the relevant literature.
Aged ; Angiography ; Angiomyolipoma ; Arteries ; Female ; Fever ; Flank Pain ; Hematoma ; Humans ; Hydronephrosis ; Kidney* ; Needles ; Pyelonephritis* ; Rupture ; Rupture, Spontaneous* ; Tomography, X-Ray Computed ; Ultrasonography ; Uterine Prolapse ; Vascular Diseases

Angiomyolipomas commonly originate from renal parenchyma but extremely rarely from perinephric space. We report a case of angiomyolipoma of the perinephric space confirmed by radical nephrectomy. A 13-year-old boy presented with left flank pain and abdominal distension, first experienced five months earlier. Ultrasonography and CT indicated that in the space surrounding the left kidney, a huge fat-containing mass with linear strands was present.
Adolescent ; Angiomyolipoma* ; Flank Pain ; Humans ; Kidney ; Male ; Nephrectomy ; Ultrasonography