Renal angiomyolipoma with malignant transformation, simultaneous occurrence with malignity and other complex clinical situations

Renal angiomyolipoma is a benign kidney tumor, which is characterized by the presence of mature or immature fat tissue, thick-walled blood vessels, and smooth muscles. However, there is a rare possibility of transformation to a malignancy. This transformation could be toward sarcoma. And also angiomyolipoma could be associated with renal adenocarcinoma in the same kidney. The aim of this study is to show the association of angiomyolipoma with complex clinical situations such as malign transformation, simultaneous occurrence with adenocarcinoma, bilateral tumors with tuberous sclerosis or Wunderlich Syndrome. Findings of clinical presentation, pathological evaluation, urography, ultrasonography, and computerized tomography of 19 patients who were diagnosed angiomyolipoma in our clinic during 1994–2003 were examined retrospectively. Our records indicated that radical nephrectomy was performed in three cases of angiomyolipoma in which the differential diagnosis from adenocarcinoma could not be made and in another case of angiomyolipoma, which was associated with adenocarcinoma. Simple nephrectomy was performed in four symptomatic angiomyolipoma cases with tumor size larger than 4 cm and partial nephrectomy in another case. In one case, renal angiomyolipoma was associated with adenocarcinoma in the same kidney. In one case, post-operative recurrence of angiomyolipoma developed 7 months after nephrectomy. This patient was diagnosed low-grade leiomyosarcoma. Angiomyolipoma is regarded as a benign tumor of the kidney; however, it may also show aggressive behaviors and rarely transform to sarcoma. It may also exist in the same kidney along with adenocarcinoma or sarcoma.     

Tuberous sclerosis complex and renal angiomyolipoma. Collective review.

Numerous case reports of renal angiomyolipoma with or without tuberous sclerosis continue to be published with increasing frequency in the urologic literature. The need for a comprehensive and updated review of the subject is timely. A collective pathologic, clinical, and radiologic review of the subjects of tuberous sclerosis complex and renal angiomyolipoma is presented; and a plan for the urologic management is discussed.     

Management of hemorrhage secondary to renal angiomyolipoma

A case of bilateral angiomyolipoma which was complicated with retroperitoneal massive hemorrhage and in which right-nephrectomy was performed is reported. Eight years ago, this patient had tuberous sclerosis and underwent open renal biopsy with which the diagnosis was confirmed. This patient was admitted for shock caused by the retroperitoneal massive hemorrhage from tumor. For about 30 days, the patient was treated conservatively, such as blood transfusion and hyperalimentation, but retroperitoneal massive hemorrhage reoccurred and the patient underwent right-nephrectomy. The treatment for bilateral angiomyolipoma complicated with retroperitoneal massive hemorrhage is discussed.     

Giant renal angiomyolipoma

We present a case report of a renal angiomyolipoma with the special feature of its big size at the moment of the diagnosis. It is appreciated an important alteration of the kidney morphology and the repercussion produced in the rest of the abdominal organs. Due to this an exeresis with nefrectomy is performed. We do a bibliographic review and we analyzed the relevant aspects of this tumour.     

Juxtaglomerular cells in renal angiomyolipoma. Ultrastructural observation

We have studied a case of renal angiomyolipoma by electron microscopy and found juxtaglomerular cells with typical rhomboid and spherical granules, in addition to smooth muscle cells, fat cells, and abnormal blood vessels. To our knowledge, this is the first ultrastructural demonstration of juxtaglomerular cells in renal angiomyolipoma.     

Management of renal angiomyolipoma: a report of 53 cases

OBJECTIVE: To evaluate the clinical, therapeutic and prognostic aspects of renal angiomyolipoma (AML) in patients either monitored by clinical and radiological follow-up or treated by surgical therapy. PATIENTS AND METHODS: Fifty-three patients with renal AML were divided in two groups; 33 patients in group 1 were monitored by annual clinical and ultrasonographic follow-up and 20 in group 2 were treated with surgical therapy. Two patients had tuberous sclerosis (TS) with synchronous bilateral and multiple lesions. Apart from the patients with TS, there were 38 lesions in group 1 and 25 in group 2. The mean (range) follow-up of group 1 was 60.2 (12-164) months. RESULTS: In group 1, the diagnosis was most often incidental, after ultrasonography performed for symptoms unrelated to AML. In group 2, the suspicion of a malignant renal lesion, and spontaneous tumour rupture with bleeding and perirenal haematoma, were the main indications for surgical treatment. The mean lesion diameter was significantly greater in group 2 (5.4 cm) and in symptomatic patients (8.1 cm). In group 1, 92% of renal AMLs showed no radiographic changes, serious complications or new renal or extrarenal lesions during the follow-up. Only three lesions grew, after 22, 85 and 164 months, respectively. Of the 20 patients in group 2, 14 underwent conservative surgery. CONCLUSION: Small (<4 cm) isolated AMLs, detected incidentally, showed a low risk of developing during long-term follow-up. Such patients may be followed conservatively by ultrasonography every 2 years. Spontaneous perinephric haemorrhage is related to the size of the lesion. When surgery is indicated (by symptoms or diagnostic doubt), a conservative procedure can be performed in most of cases.     

Bilateral renal angiomyolipoma

Angiomyolipomas are frequent tumours of the kidneys. They are very important in the differential diagnosis of other kidney tumours; sometimes they can present a large size and manifest as an acute massive retroperitoneal haemorrhage. They generally should not be treated unless there are life-threatening problems. In this case report, we present an acute surgical condition due to rupture and haemorrhage of a giant angiomyolipoma. In addition, we review the literature on angiomyolipomas and their severe complications in order to help young surgeons who may be involved in such difficult and life-threatening cases as ours.     

Rupture of renal angiomyolipoma

Spontaneous rupture of renal angiomyolipoma is a rare, but life threatening condition. A case is reported which illustrates the role of computerized tomography in the diagnosis and management of this condition. Rupture of these benign lesions should be managed initially with blood transfusion and angiographic embolization if haemorrhage continues. In cases where surgery is necessary, a kidney-sparing technique should be performed when possible, such as enucleation of the lesion or partial nephrectomy.     

Exophytic renal angiomyolipoma. A case report

A case of a large exophytic renal angiomyolipoma is presented. Despite the features on excretory urography suggestive of an extrarenal mass, computed tomography provided information concerning the origin and pathological nature of the lesion.     

Intra-sinusal renal angiomyolipoma. Differential diagnosis from renal artery aneurysm

We report a case of atypical renal angiomyolipoma (AML) because of its clinic presentation like colic renal pain, its uncommon intrasinusal location, its low fatty content, and especially because of the diagnostic doubt with a renal artery aneurysm that could not be resolved before the surgery in spite of making Doppler ultrasound, renal one sided arteriography, computed tomography (CT) and magnetic resonance imaging (MRI). We gave up doing a percutaneous needle biopsy because of the location, the association with hematoma and the possibility of a vascular origin. It has been said that diagnostic images, mainly ultrasound and CT, have a high capacity to get a renal AML diagnosis before the surgery. However when there is an atypical characteristics association like we have talked about, dismissing other pathologies is necessary. We believe AML must be considered one of these because of its difficult differential diagnosis.     

Diagnostic and therapeutic problems in multicentric renal angiomyolipoma.

Multicentric renal angiomyolipoma is a rare form of benign tumor. However, its effective incidence as evaluated in autopsy studies may be as high as 8%. There are 2 main types of renal angiomyolipoma, that is isolated forms and those associated with other diseases, such as phakomatosis, polycystic kidneys and fibromuscular dysplasia. The tumor may also display malignant behavior with local invasiveness and regional lymph node involvement. However, the clinical course is benign and multicentricity is important for prognosis. Histopathological diagnosis often is difficult. Immunohistochemical analysis of surgical specimens using a panel of monoclonal antibodies, including HMB-45 and actin, enabled us to make a definitive diagnosis in 3 cases of multicentric renal angiomyolipoma.     

Recurrent renal epithelioid angiomyolipoma

Renal angiomyolipoma has traditionally been considered a benign tumor. Recently, a variety of epithelioid angiomyolipomas with malignant potential have been described. We report an adrenal recurrence in a patient who had a cellular angiomyolipoma removed 4 years earlier.     

Spontaneous rupture of renal angiomyolipoma

We report a case of renal angiomyolipoma with retroperitoneal hemorrhage treated by enucleation in a 47 year-old male. The mass in the anterior side of the left kidney, revealed by sonography and CT, was diagnosed as angiomyolipoma with a retroperitoneal hematoma caused by its spontaneous rupture. Removal of hematoma and enucleation of the tumor were performed after the diagnosis. Diagnosis and treatment of ruptured renal angiomyolipoma are discussed.