1/131. 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.- - - - - - - - - - ranking = 1keywords = kidney (Clic here for more details about this article) |
2/131. amyloid deposition in renal angiomyolipoma.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.- - - - - - - - - - ranking = 1keywords = kidney (Clic here for more details about this article) |
3/131. 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.- - - - - - - - - - ranking = 3keywords = kidney (Clic here for more details about this article) |
4/131. angiomyolipoma of the kidney and lymph nodes.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.- - - - - - - - - - ranking = 7keywords = kidney (Clic here for more details about this article) |
5/131. angiomyolipoma of the parotid gland: a case report.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.- - - - - - - - - - ranking = 1keywords = kidney (Clic here for more details about this article) |
6/131. Mucocutaneous angiomyolipoma. A report of 2 cases arising in the nasal cavity.OBJECTIVE: angiomyolipoma (AML) is a distinctive tumor that usually occurs in the kidney and rarely in the liver. angiomyolipoma of other sites is extremely rare, and, to our knowledge, only 2 cases have been described in the nasal cavity. We present 2 additional cases of AML of the nasal cavity and discuss the difference between them and renal AML. case reports AND PATHOLOGIC FINDINGS: Two tumors in a 66-year-old man and an 88-year-old woman without tuberous sclerosis are described. They showed 20-mm, well-circumscribed, polypoid shapes. Histologically, they were composed of mature smooth muscle cells, fat cells, and various-sized blood vessels. In addition, aggregated small lymphocytes were noted. Neither epithelioid smooth muscle cells nor HMB45 immunoreactivity was seen in either case. CONCLUSIONS: The clinicopathologic features of AML of the nasal cavity are distinct from renal and hepatic AML and are common to those of AML arising in the skin and oral and pharyngeal mucosa. The term mucocutaneous angiomyolipoma is thought to be appropriate to express these characteristic tumors.- - - - - - - - - - ranking = 1keywords = kidney (Clic here for more details about this article) |
7/131. Lymphangiectasia within angiomyolipoma in a tuberous sclerosis patient.This is a presentation of a case of tuberous sclerosis with multifocal hamartomas in the retroperitoneum, both kidneys, and the liver. Lymphangiectasia and numerous ectatic lymphatic channels penetrating through the retroperitoneal angiomyolipoma were demonstrated by lymphography and computed tomography. The findings in our study may document the presence of degenerative change in the lymphatic system--not just in elastic vessels--an association which has not yet been reported in the radiological literature.- - - - - - - - - - ranking = 1keywords = kidney (Clic here for more details about this article) |
8/131. Malignant angiomyolipoma of the liver: a hitherto unreported variant.AIMS: After their original recognition in the kidney, angiomyolipomas (AMLs) have been reported in the liver for more than 20 years. In the kidney, five cases of malignant AML have been reported. We report the first case of malignant hepatic AML. methods AND RESULTS: A 70-year-old female patient presented with abdominal discomfort. Clinical examination revealed a palpable liver. CT scan showed a polymorphous hypervascular lesion in the right liver lobe. A biopsy was taken and resulted initially in a differential diagnosis between a hepatocellular carcinoma, a metastatic tumour (possibly of renal origin) and angiomyolipoma (AML). After immunohistochemistry, a hepatic AML was suggested, given the immunoreactivity for HMB45/NKIC-3. The mass was resected 5 years later because of relapsing abscess formation. Gross examination of the resection specimen showed a focally encapsulated brown mass with focal necrosis. Microscopic examination showed a tumour growing in sheets, separated by sinusoidal-like vessels. Most of the tumour cells had a large, polygonal, clear cytoplasm, often with eosinophilic condensation around the nucleus. There was prominent vascular invasion. immunohistochemistry (reactivity for HMB-45, NKIC-3, S100 and alpha smooth muscle actin, negativity for cytokeratin and vimentin) and electron microscopy confirmed the diagnosis of monomorphic epithelioid AML with prominent vascular invasion. Seven months after tumour resection, the patient died of recurrent disease. CONCLUSIONS: This case highlights the importance of immunohistochemistry and electron microscopy in diagnosing this type of tumour. Possibly, in the past, malignant AML of the liver has been misdiagnosed as HCC.- - - - - - - - - - ranking = 2keywords = kidney (Clic here for more details about this article) |
9/131. Malignant pigmented clear cell epithelioid tumor of the kidney: clear cell ("sugar") tumor versus malignant melanoma.A 73-year-old woman presented with an hemorrhagic kidney tumor initially interpreted as a renal cell carcinoma (RCC). A retroperitoneal recurrence infiltrating the duodenal wall was made up of clear cells, some of which contained Fontana-Masson positive pigment, immunopositive for HMB-45, S-100 protein, actin, and vimentin. The same immunohistochemical profile was retrospectively reproduced in the kidney tumor, where melanosomes were also found ultrastructurally. Lipomatous differentiation was not observed. There was no history of malignant melanoma (MM), or stigmata of tuberous sclerosis. The patient died of disease 5 years after the initial diagnosis. This neoplasm can be considered as a malignant, pigmented, clear-cell epithelioid variant of angiomyolipoma, or "sugar" tumor of the kidney, with the peculiarity of having a previously unreported component of pigmented cells visible on light microscopy. This finding raises the possibility that the exceptional cases of MM reported in renal parenchyma may be pigmented variants of epithelioid angiomyolipoma rather than true MM.- - - - - - - - - - ranking = 7.0123750189446keywords = kidney, neoplasm (Clic here for more details about this article) |
10/131. Renal angiomyolipoma with epithelioid sarcomatous transformation and metastases: demonstration of the same genetic defects in the primary and metastatic lesions.angiomyolipoma (AML) is a benign neoplasm that occurs either sporadically or in patients with tuberous sclerosis complex (TSC) and shows frequent allelic losses at chromosome arm 16p. It has been suggested recently that the melanogenesis marker-positive perivascular epithelioid cell (PEC) has been found consistently in AML. The authors report a 50-year-old woman without evidence of TSC affected by classic renal AML containing an area composed of atypical epithelioid cells with the same morphoimmunophenotypic characters of PEC. After 7 years from surgical removal of the lesion, the patient developed a local recurrence and successive lung and abdominal metastases that showed morphologic and immunohistochemical features overlapping those of the epithelioid area of the previously removed AML. Genetic analysis showed that the classic AML and its epithelioid area as well as the pulmonary and abdominal metastases shared the same allelic loss on chromosome arm 16p. Based on these findings, the authors view this case as evidence of a malignant transformation of a classic AML with morphologic, immunophenotypic, and genetic demonstration of its clonal origin.- - - - - - - - - - ranking = 0.012375018944606keywords = neoplasm (Clic here for more details about this article) |
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