1/316. Hepatic angiomyolipoma: report of changing size and internal composition on follow-up examination in two cases. We present two cases of hepatic angiomyolipoma in which the size and internal composition of the tumor changed during the course of follow-up study. The tissue elements composing the tumor are thought to grow or regress independently during the disease's clinical course. Radiologists should be aware that hepatic angiomyolipoma can change in size and internal composition during its natural course. ( info) |
2/316. Percutaneous nephrolithotomy with renal angiomyolipomas: a rare challenge. Renal angiomyolipomas (AML) are vascular tumors associated with a risk of spontaneous bleeding. Renal trauma may also initiate such hemorrhage. We present a case in which we initially avoided direct puncture and the possible risk of bleeding through extensive renal AMLs and then subsequently performed a direct puncture through the tumors. A 21-year-old obese male patient with tuberous sclerosis and mental retardation presented to our institution with left renal colic and was found to have a staghorn calculus. A CT scan revealed extensive bilateral renal AMLs. The patient had previously undergone renal angioinfarction for an enlarging right-sided AML, and nuclear renography demonstrated 70% function from the left side. The patient had a nephrostomy access created on the morning of a scheduled percutaneous nephrolithotomy under three-dimensional CT guidance. There was no clinically significant bleeding. Intraoperatively, a second access site was required in order to render the patient stone free. This was done using standard biplanar fluoroscopic technique and traversed an AML. Both tracts were balloon dilated prior to placement of a 34F Amplatz sheath. Postoperatively, the patient had an uneventful recovery. A CT scan performed 1 day postoperatively revealed no retroperitoneal collection. This case demonstrates that renal access can be achieved with remarkable accuracy using 3D CT imaging. Furthermore, although this approach seems most prudent in the case of extensive renal AMLs, fluoroscopically guided renal access and dilation to 34F was not associated with bleeding in this patient. ( info) |
3/316. Renal cell carcinoma with a fatty component mimicking angiomyolipoma on CT. A very unusual CT appearance of renal cel carcinoma is presented, in which the fatty density mimicked a benign angiomyolipoma. ( info) |
4/316. Renal angiomyolipoma resembling gastrointestinal stromal tumor with skenoid fibers. We report an unusual case of renal angiomyolipoma occurring in 68-year-old man. The tumor lacked well-developed vascular and adipose components and was composed almost exclusively of smooth muscle cells. Numerous skenoid-like periodic acid-Schiff-positive globules were interspersed between the tumor cells; the lesion therefore closely resembled a low-grade stromal tumor of the gastrointestinal tract. The HMB45-positive/CD34-negative immunophenotype was essential for the diagnosis of angiomyolipoma. Neither gastrointestinal tumor nor any signs of tuberous sclerosis were found. This lesion should be included in the list of morphologic variations of angiomyolipoma, which may cause diagnostic difficulties. ( info) |
5/316. Composite renal cell carcinoma and angiomyolipoma: a study of the histogenetic relationship of the two lesions. The purpose of the present study was to investigate the possible histogenetic relationship of renal cell carcinoma (RCC) and angiomyolipoma (AMYL) occurring in the same renal nodule by examining two cases of composite RCC and AMYL in patients without stigmata of tuberous sclerosis and by reviewing the medical literature of similar cases. Case 1 represents an epithelioid variant of AMYL with multiple additional nodules of typical AMYL in a surgically removed kidney. The patient subsequently developed a lesion consisting of a mixture of epithelioid variant of AMYL and RCC 24 months later in the retroperitoneum and, an additional 4 months later, in the liver. The RCC cells resembled mononucleated epithelioid cells of the epithelioid AMYL except that they were focally reactive with epithelial membrane antigen (EMA) in the retroperitoneum and focally reactive with both EMA and cytokeratin (CK) in the liver. Case 2 consisted of a typical AMYL admixed with a chromophil cell RCC. A review of the medical literature revealed seven additional cases with histopathological findings similar to this case. All cases had multiple foci of typical AMYL. Immunostaining results are available in five tumors. Chromophil RCC showed variable reactivity with CK and EMA. In addition, RCC in the two cases in the present study also displayed a positive reaction with mucin staining and a positive reactivity with carcinoembryonic antigen. There appears to be a spectrum of histopathological and immunohistochemical changes from the epithelioid variant of AMYL through a mixed epithelioid AMYL/RCC to chromophil RCC in three successive specimens in case 1. Moreover, the intimate admixture of AMYL and RCC and the similar expression of epithelial markers of RCC in the two cases in the present study, as well as other cases in the literature, suggest that some RCC develop from the same precursor cell as AMYL or from a component of AMYL. ( info) |
6/316. Giant retroperitoneal angiomyolipoma. A case report. We discuss a case of a giant renal angiomyolipoma. A 28 year-old woman presented with a history of a painless and swelling abdominal mass. A computerized tomography (CT) scan of the abdomen demonstrated a 27 x 13 x 11 cm tumor in the right retroperitoneum. At laparotomy, a wide excision of the mass was performed and the histopathological examination of the resected specimen revealed the presence of an angiomyolipoma. The clinical, radiological and pathological findings of this case are reported with a review of the literature. ( info) |
| An irregular tumor shadow, seen on the left kidney in a 48-year-old woman by computed tomography, was pathologically diagnosed as 'angiomyolipoma'. HMB-45 immunoreactivity distinguished angiomyolipoma from renal cell carcinoma of sarcomatoid type. The amyloid deposition was limited to the tumor. M-protein and Bence-Jones protein were negative. For amyloid protein characterization, immunohistochemical studies were performed with antiamyloid A, anti-kappa, anti-lambda, anti-prealbumin and anti-beta-2 microglobulin, but none reacted with the amyloid. This is the first documented case of amyloid deposition in angiomyolipoma and may represent a novel precursor protein of amyloid. ( info) |
8/316. tuberous sclerosis associated with multiple hepatic lipomatous tumors and hemorrhagic renal angiomyolipoma. We report a case of tuberous sclerosis associated with hepatic lipomatous tumors and renal angiomyolipomas. Abdominal ultrasonography revealed a high echoic large tumor in the left kidney. A provisional diagnosis of angiomyolipomas of the kidney was made based on computed tomography. Subsequent laparotomy revealed that the extracted tumor was renal angiomyolipoma. It was also revealed that there was an association with hepatic lipomatous tumors thought to be lipomas or angiomyolipomas by liver biopsy. Nearly half of all cases of angiomyolipoma in the kidney are reported as occasional association with tuberous sclerosis complex, but lipomatous tumors in the liver are rare. ( info) |
| angiomyolipoma (AML) is a benign mesenchymal tumor predominantly occurring in the kidney. Despite its low incidence of 0.07-0.03% in an unselected population, this tumor is well known, because the typical AML can be diagnosed without histological confirmation by a combination of ultrasound (US) and computerized tomography (CT) imaging in up to 95% of cases. In contrast, simultaneous involvement of the kidney and the regional lymph nodes is less known and might be confused with metastasizing malignant tumor. We report a case of the very uncommon simultaneous involvement of the kidney and the lymph nodes in AML. ( info) |
| angiomyolipoma is a hamartomatous process that most frequently occurs as a single lesion or multiple foci in the kidneys of patients affected by tuberous sclerosis. angiomyolipoma can also arise in extrarenal sites, among which the liver is the most frequently recorded. Only rare cases of angiomyolipoma located in the head and neck region (ear and oral and nasal cavity) have been described. The purpose of the present article is to report a case of angiomyolipoma of the parotid gland. A 68-year-old woman appeared for treatment with a slow-growing nodule located in her right parotid gland. Ultrasound examination revealed a heterogeneous nodule with well-defined margins. The nodule was surgically removed by total parotidectomy and showed the characteristic appearance of angiomyolipoma, with an admixture of fat smooth muscle cells, and tortuous, thick-walled blood vessels. Careful physical examination of the patient failed to reveal features of tuberous sclerosis. angiomyolipoma should be considered in the differential diagnosis of mesenchymal lesions involving the salivary gland. ( info) |