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This tumor arises from the mesenchymal elements of the kidney and exhibits a collection of blood vessels, smooth muscle, and mature adipose tissue. These tumors may remain silent for many years or are discovered incidentally on radiographs. It may also present with flank or abdominal pain in 50% of patients or hematuria in 20% of patients.

The most important association of this tumor is with tuberous sclerosis. This tumor is one of the major diagnostic criteria of the disease and occurs in 47% of these patients. In this setting, 71% are bilateral and 87% are multiple. Overall, however, there are 4 times as many sporadic angiomyolipomas as there are cases associated with tuberous sclerosis.


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INCIDENCE Most common mesenchymal tumor of the kidney
0.7-2% of all kidney tumors
AGE RANGE-MEDIAN Mean 41 years


Tuberous Sclerosis  
von Recklinghausen disease  
von Hippel-Lindau syndrome  
Autosomal dominant Adult polycystic disease  

Concurrent Angiomyolipoma and Renal Cell Neoplasia: A Study of 36 Cases

Rafael E. Jimenez, etal.

Mod Pathol 2001;14:157-163 Abstract quote

Little is known about the association of angiomyolipoma and adult renal-cell neoplasia.

We studied the clinicopathologic features of 36 patients with concurrent angiomyolipoma and renal-cell neoplasia from the consultation and surgical pathology files of nine institutions. HMB-45 immunoreactivity was analyzed in both neoplasms.

Twenty-five sporadic cases of patients with angiomyolipoma and renal-cell neoplasia and 11 cases of patients with tuberous sclerosis, as defined by Gomez’ criteria, had mean ages of 59 and 53 years, respectively, and female–male ratios of 2:1 and 5:1, respectively. The mean size of the angiomyolipomas was 1 cm in the sporadic cases and 3 cm in those patients with tuberous sclerosis (medians: 0.5 and 3 cm, respectively, P = .002). The mean sizes of the renal-cell neoplasms were 5 cm in sporadic cases and 6 cm in patients with tuberous sclerosis (medians: 4 and 5 cm, respectively; P = .88).

In both clinical settings, angiomyolipoma was more commonly the incidental tumor. Clear-cell (conventional) renal-cell carcinoma was the most common renal-cell neoplasm in both groups of patients, accounting for approximately two thirds of the tumors.

In patients with tuberous sclerosis, 27% of renal-cell neoplasms were oncocytomas, compared with 8% in sporadic cases (P = .15). Papillary neoplasia, chromophobe, and collecting-duct renal-cell carcinoma were found only in sporadic cases. All of the 22 renal-cell neoplasms studied were negative for HMB-45, whereas all 25 angiomyolipomas studied were positive.

Renal Disease in Adults With TSC2/PKD1 Contiguous Gene Syndrome

Guido Martignoni, M.D. ; Franco Bonetti, M.D. ; Maurizio Pea, M.D. ; Regina Tardanico, M.D. ; Matteo Brunelli, M.D. ; John N. Eble, M.D.

From the Dipartimento di Patologia-Sezione Anatomia Patologica (G.M, F.B., M.P., M.B.), Universita' di Verona, Verona; Dipartimento di Anatomia Patologica (R.T.), Universita' di Brescia, Brescia, Italy; and Roudebush VA Medical Center (J.N.E.), Indiana University, Indianapolis, Indiana, U.S.A.

Am J Surg Pathol 2002;26:198-205 Abstract quote

The most common renal lesions of tuberous sclerosis complex, an autosomal-dominant syndrome resulting from losses of TSC1 (9q34) or TSC2 (16p13.3), are renal cysts and angiomyolipomas. Epithelial neoplasms are less common. The TSC2 gene lies adjacent to PKD1 , the major gene responsible for autosomal-dominant polycystic kidney disease. Recently, a deletion mutation disrupting both TSC2 and PKD1 has been described in young children with tuberous sclerosis complex with severe renal cystic disease. This disease has been termed the TSC2/PKD1 contiguous gene syndrome.

We describe the lesions in the resected kidneys of two adults with TSC2/PDK1 contiguous gene syndrome, at the time of the nephrectomies: a 31-year-old man and his 44-year-old mother. The four kidneys were enlarged reniform masses composed of cysts lined by flattened, cuboidal, or, infrequently, large deeply eosinophilic epithelial cells. The kidneys also contained numerous classic angiomyolipomas and rare intraglomerular microlesions. In the son the largest tumor was a monotypic epithelioid angiomyolipoma. In the wall of his left renal pelvis there was a plaque-shaped, HMB-45-positive localized lesion of lymphangioleiomyomatosis. This is the first description of the renal lesions in adults with genetically confirmed TSC2/PDK1 contiguous gene syndrome.

The pathologic findings highlight the importance of thorough sampling for histology in polycystic kidney diseases and indicate that the observation of an angiomyolipoma in biopsy material from patients with enlarged cystic kidneys should suggest the diagnosis of TSC2/PKD1 contiguous gene syndrome, even in cases without ultrasonographic and macroscopic evidence of angiomyolipoma.


Derived from a perivascular epithelial cells (PEC) Type of muscle cells which expresses HMB-45

Apparent preferential loss of heterozygosity at TSC2 over TSC1 chromosomal region in tuberous sclerosis hamartomas.

Carbonara C, Longa L, Grosso E, et al.

Genes Chrom Cancer 1996;15:18–25.

Frequent allelic losses at chromosome 16p, site of the lesion related to tuberous sclerosis complex (TSC), frequently shows loss of heterozygosity of variable portions of chromosome arm 16p encompassing the TSC2 gene locus in both sporadic and TSC-associated tumors

Molecular Genetic Evidence for Different Clonal Origin of Components of Human Renal Angiomyolipomas

Liang Cheng, M.D.; Jian Gu, M.S.; John N. Eble, M.D.; David G. Bostwick, M.D.; Cheryl Younger, M.D.; Gregory T. MacLennan, M.D.; Fadi W. Abdul-Karim, M.D.; William A. Geary, M.D.; Michael O. Koch, M.D.; Shaobo Zhang, M.D.; Thomas M. Ulbright, M.D.

From the Departments of Pathology (L.C., J.G., J.N.E., C.Y., W.A.G., S.Z., T.M.U.) and Urology (M.O.K.), Indiana University School of Medicine, Indianapolis, Indiana; Bostwick Laboratories (D.G.B.), Richmond, Virginia; and the Department of Pathology (G.T.M., F.W.A.-K.), Case Western Reserve University, Cleveland, Ohio, U.S.A.

Am J Surg Pathol 2001;25:1231-1236 Abstract quote

Renal angiomyolipoma is a benign neoplasm composed of variable proportions of blood vessels, smooth muscle, and adipose tissue.

Smooth muscle, adipose tissue, blood vessels, and adjacent normal kidney tissue were separately microdissected from sections prepared from formalin-fixed, paraffin-processed tissues from angiomyolipomas from 18 women. X chromosome inactivation analysis using the methylation pattern at exon 1 of the human androgen receptor gene on chromosome Xq11–12 was used to study the clonal origin of each component.

Nonrandom inactivation of X chromosomes was found in six of the 15 informative tumors. The smooth muscle and adipose tissue showed differing patterns of nonrandom inactivation of X chromosomes in five angiomyolipomas and the same pattern of nonrandom inactivation of X chromosomes in one. Samples from the blood vessels showed random inactivation of X chromosomes in all informative cases.

Our data showed that the adipose tissue and smooth muscle cells of renal angiomyolipoma are both monoclonal but may arise independently. The coexistence of tumor subclones with morphologic heterogeneity can lead to the formation of a clinically detectable tumor.



Lobular and yellow with areas of firm gray tumor

Hemorrhage is common and may replace most of the tumor

Mean 9.4 cm but ranges from 3-20 cm

Compress the surrounding structures and may rupture into the renal calyces or renal vein

Multiple in 20%


Pleomorphic Angiomyolipoma of Digestive Tract: A Heretofore Unrecognized Entity.

Prasad ML, Keating JP, Teoh HH, McCarthy SW, Battifora H, Wasef E, Rosai J.

Departments of Pathology, Memorial Sloan-Kettering Cancer Center, New York, NY.

Int J Surg Pathol 2000 Jan;8(1):67-72 Abstract quote

Two cases of pleomorphic angiomyolipoma (AML) composed of bizarre epithelioid smooth muscle cells located in the gastrointestinal tract are reported. One involved the appendix of a 6-year-old girl, and the second the cecum of a 22-year-old woman. In both instances the tumor cells were immunoreactive for HMB-45 and A103.

To the best of our knowledge, this peculiar variant of an AML has not previously been recognized in this location.


Concurrent angiomyolipomas and renal cell carcinoma harboring metastatic foci of mammary carcinoma in the same kidney: An incidental autopsy finding in a patient with a follow-up of thirty years

J. Fernando Val-Bernal, MD, PhD
Fernando Villoria, MD
M. Angeles Pérez-Expósito, MD

Ann Diagn Pathol 2001;5:293-299 Abstract quote

The synchronous occurrence of three different types of renal tumor in a patient is rare.

We report a case of conventional (clear cell) renal cell carcinoma harboring metastatic foci of mammary carcinoma associated with two angiomyolipomas in the left kidney incidentally discovered at the autopsy. The patient was a 75-year-old woman, without the tuberous sclerosis complex, who had undergone left radical mastectomy and radiotherapy for an infiltrating duct carcinoma of breast 30 years before. This tumor was widely disseminated at autopsy, but the nontumorous renal parenchyma was free of metastases.

To the best of our knowledge this combination of neoplasms has not been described before. This case shows the important role played by autopsy in the accurate investigation of interrelations among coexisting tumors.



Mixture of blood vessels, smooth muscle, and adipose tissue composed in a haphazard fashion

May have nuclear enlargement and hyperchromasia of the smooth muscle cells

Blood vessels may be thickened with abnormally formed walls

Atypical angiomyolipoma of kidney in a patient with tuberous sclerosis: a case report with p53 gene mutation analysis.

Ma L, Kowalski D, Javed K, Hui P.

Department of Pathology, Yale University School of Medicine, New Haven, Conn 06510, USA.

Arch Pathol Lab Med. 2005 May;129(5):676-9. Abstract quote  

Angiomyolipoma (AML) is the most common benign mesenchymal tumor of the kidney. It belongs to the family of perivascular epithelioid cell tumors and is typically composed of blood vessels, adipose tissue, and smooth muscle- like cells, which are characteristically positive for HMB-45. Results of recent studies suggest that p53 mutation may play an important role in AML progression.

Here, we describe a locally destructive renal AML in a patient with tuberous sclerosis. The tumor consisted of mostly epithelioid cells with marked nuclear pleomorphism and frequent mitoses and was positive for HMB-45. The diagnosis of atypical epithelioid AML was made. Codon alteration in the p53 gene was not detected, despite focal p53 immunoreactivity and single nucleotide polymorphism at exon 6.

Our finding indicates no definite link between p53 abnormalities and the atypical appearance of AML. To the best of our knowledge, this is the second renal AML case investigated for p53 mutations.
Cystic angiomyolipoma of the kidney: a clinicopathologic description of 11 cases.

Davis CJ, Barton JH, Sesterhenn IA.

1Department of Genitourinary Pathology, Armed Forces Institute of Pathology, Washington, DC, USA.

Mod Pathol. 2006 May;19(5):669-74. Abstract quote  

This report deals with 11 examples of renal angiomyolipomas (AML) which appear to include an epithelial element as a part of the neoplasm in the form of gross or microscopic cysts-usually both. There were seven females and four males between the ages of 20 and 70 years with mean age of 45 years. Three of these were known to be symptomatic: intermittent flank pain and gross hematuria for 2 months; recurrent hematuria both before and after flank trauma and a third patient with acute abdomen due to a ruptured tumor blood vessel.

Cysts were described in three of the six cases where radiographic data were available. Seven tumors were in the right kidney and four in the left. In gross descriptions, cysts were mentioned in seven and they ranged from 6.0 to 2.0 cm with a median and mean maximal diameter of 5.0 and 4.0 cm, respectively.

Microscopically, virtually all of the tumors included multiple smaller cysts and these were lined by flat, cuboidal or columnar epithelium and occasionally hobnail epithelium. There was usually a subepithelial collar of poorly differentiated cells, but the solid element of all tumors was myomatous angiomyolipoma; only one case had any adipose tissue. A dominant histological feature was the prominent lymphatic channels-identical to those of lymphangiomyomas and myomatous or triphasic AMLs. They are much more conspicuous in these cystic cases. Immunohistochemically, all tumors tested were reactive with actin, desmin and HMB-45, with the latter being more intensely positive in the subepithelial collars.

Estrogen and progesterone receptors were usually positive, also. The behavior of these lesions appears to be no different from that of other AMLs.

Oncocytoma-like Angiomyolipoma.

Martignoni G, Pea M, Bonetti F, Brunelli M, Eble JN.

Dipartimento di Patologia-Sezione Anatomia Patologica, Universita' di Verona, Verona, Italy (Drs Martignoni, Pea, Bonetti, and Brunelli); and Roudebush VA Medical Center, Indiana University, Indianapolis (Dr Eble).

Arch Pathol Lab Med 2002 May;126(5):610-2 Abstract quote

We report the clinical, pathologic, and immunohistochemical features of an unusual tumor of the kidney composed of densely eosinophilic, polygonal epithelioid cells. The patients were a 56-year-old woman and a 35-year-old man. The renal tumors were discovered during follow-up for breast carcinoma and evaluation for abdominal pain, respectively.

The tumors closely resembled oncocytoma in routine sections, but were negative for epithelial markers and positive for HMB-45, a pattern of reactions characteristic of angiomyolipoma. In the woman, a single additional microscopic angiomyolipoma was present in the renal parenchyma at a distance from the main tumor. Both patients are alive without recurrence 7 and 10 years after surgery, respectively.

Based on clinical, morphologic, and immunophenotypic features, we conclude that these tumors are oncocytoma-like angiomyolipomas.


Renal Angiomyolipoma With Epithelioid Sarcomatous Transformation and Metastases Demonstration of the Same Genetic Defects in the Primary and Metastatic Lesions

G. Martignoni, M.D.; M. Pea, M.D.; G. Rigaud, Ph.D.; E. Manfrin, M.D.; C. Colato, M.D.; G. Zamboni, M.D.; A. Scarpa, M.D.; R. Tardanico, M.D.; M. Roncalli, M.D., Ph.D.; F. Bonetti, M.D.

From the Dipartimento di Patologia—Sezione Anatomia Patologica (G.M., M.P., G.R., E.M., C.C., G.Z., A.S., F.B.), Università di Verona; the Istituto di Anatomia Patologica (R.T.), Università di Brescia; and the Anatomia Patologica (M.R.), Istituto Clinico Humanitas, Università di Milano, Milan, Italy.

Am J Surg Pathol 2000;24:889-894 Abstract quote

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.

Malignant epithelioid angiomyolipoma (Sarcoma ex angiomyolipoma)
Am J Surg Pathol 2001;25:121-126
One case, HMB45 positive arising from angiomyolipoma
Originally treated with partial nephrectomy
Developed liver nodules 3 years later
50% reduction in size after 2 cycles of doxorubicin



Melanoma Markers in Angiomyolipoma of the Liver and Kidney A Comparative Study

Hala R. Makhlouf, MD, PhD, Kamal G. Ishak, MD, PhD, Raj Shekar, MD, Isabell A. Sesterhenn, MD, Denise Y. Young, BS, and Julie C. Fanburg-Smith, MD

From the Departments of Hepatic and Gastrointestinal Pathology (Drs Makhlouf and Ishak), Genitourinary Pathology (Drs Shekar, Sesterhenn, and Young), and Soft Tissue Pathology (Dr Fanburg-Smith), Armed Forces Institute of Pathology, Washington, DC.

Arch Pathol Lab Med 2002;Vol. 126, No. 1, pp. 49–55. Abstract quote

Context.—Melanoma markers, especially the new microphthalmia transcription factor (mitf), have not been previously compared in hepatic and renal angiomyolipomas. Objectives.—To evaluate expression of the novel melanocytic markers mitf and tyrosinase in angiomyolipomas, and to compare these markers with the established markers HMB-45 and melan-A in both hepatic and renal tumors.

Design.—Clinical, histopathologic, and immunohistochemical features of 15 hepatic angiomyolipomas were compared with those of 10 renal angiomyolipomas.

Results.—No significant differences between patients with hepatic angiomyolipomas and renal angiomyolipomas were found with respect to age, gender, race, and tumor size. Hepatic angiomyolipomas exhibited a predominance of the epithelioid smooth muscle cell component, in contrast to their renal counterparts, which were predominantly spindled. The smooth muscle cells expressed HMB-45 in 100% of cases in both groups, melan-A in 14 of 15 hepatic angiomyolipomas and 8 of 9 renal angiomyolipomas, mitf in 5 of 12 hepatic angiomyolipomas versus 6 of 10 renal angiomyolipomas, and tyrosinase in 3 of 12 and 2 of 10 hepatic angiomyolipomas and renal angiomyolipomas, respectively. The extent and intensity of immunostaining with HMB-45 and melan-A were dependent on whether spindled or epithelioid cells predominated; the epithelioid cells showed stronger and more widespread reactivity than the spindled cells.

Conclusion.—We believe that the best immunohistochemical marker for confirming the diagnosis of angiomyolipoma is HMB-45, followed by melan-A. Routine use of mitf and/or tyrosinase is not indicated.


Expression of KIT (CD117) in Angiomyolipoma.

Makhlouf HR, Remotti HE, Ishak KG.

Department of Hepatic and Gastrointestinal Pathology, Armed Forces Institute of Pathology, Washington, DC, U.S.A.

Am J Surg Pathol 2002 Apr;26(4):493-7 Abstract quote

Angiomyolipoma is a unique mesenchymal tumor postulated to arise from perivascular epithelioid cells. Immunohistochemical studies have shown that angiomyolipomas express the melanocytic markers HMB-45, MART-1 (Melan A), microphthalmia transcription factor, and tyrosinase, in addition to smooth muscle actin. KIT (CD117) is a transmembrane growth factor receptor expressed in cells of melanocytic and a variety of other cell lineages. To date, KIT immunoreactivity has not been systematically studied in angiomyolipoma.

In this study we immunohistochemically analyzed a series of 21 angiomyolipomas (15 hepatic, six renal) with KIT. All were KIT positive: 14 of 21 (67%) with 3+ staining (>50% of tumor cells), 4 of 21 (19%) with 2+ staining (25-50% of tumor cells), and 3 of 21 (14%) with 1+ staining (<25% of tumor cells). In comparison, the percent of angiomyolipomas showing 3+ staining with HMB-45 was 62% and with Melan A was 52%. Positive KIT staining was detected in the epithelioid, spindle, and intermediate small round cells. Most cases showed diffuse cytoplasmic positivity. Strong perinuclear staining was present in the vacuolated clear epithelioid cells. There was focal KIT staining of fat cells. KIT was not detected in the endothelial cells lining blood vessels within the tumor. KIT may be a useful ancillary marker for the diagnosis of angiomyolipoma. A

ngiomyolipoma should be included in the differential diagnosis of KIT-positive tumors.

HMB45 Am J Surg Pathol 2001;25:65-70
This melanoma marker characteristically is positive in this tumor
Positive in 22/29 cases
Microphthalmia transcription factor expression (MITF) Am J Surg Pathol 2001;25:65-70
Study of 29 cases compared with 15 renal cell carcinomas
50% of cases showed staining in more than half of the tumor cells
MART1 (Melan A) Am J Surg Pathol 2001;25:65-70

Study of 29 cases compared with 15 renal cell carcinomas
24% of cases showed staining in more than half of the tumor cells

Renal Cell Carcinoma Associated With Prominent Angioleiomyoma-like Proliferation: Report of 5 Cases and Review of the Literature.

*Centro Consulenze Anatomia Patologica Oncologica, Centro Diagnostico Italiano, Milan, Italy daggerDepartment of Pathology, Institute National of Pediatrics, Mexico City, Mexico double daggerDepartment of Pathology, University of Bologna, Bologna, Italy section signDepartment of Pathology, Johns Hopkins Medical Institutions, Baltimore parallelGenzyme Genetics, Inc, New York, NY.

Am J Surg Pathol. 2006 Nov;30(11):1372-1381. Abstract quote

Five cases of renal cell carcinoma of clear cell type are presented, Fuhrmann's grade 2, associated with a peculiar stromal proliferation having angioleiomyoma-like features. This proliferation was particularly prominent at the interphase between the tumor edge and the surrounding normal tissues, in which it acquired the configuration of a tumor capsule. Four similar cases were taken from the literature.

We postulate that this angioleiomyoma-like change is a tumor epiphenomenon and that it represents yet another manifestation of the well-documented capacity of renal cell carcinoma to induce vascular proliferation, probably through the secretion of angiogenic and other growth factors by the tumor cells.
Incidental stromal-predominant mixed epithelial-stromal tumors of the kidney: a mimic of intraparenchymal renal leiomyoma.

Parikh P, Chan TY, Epstein JI, Argani P.

Division of Surgical Pathology, Johns Hopkins University, Baltimore, Md, USA.
Arch Pathol Lab Med. 2005 Jul;129(7):910-4. Abstract quote  

CONTEXT: Mixed epithelial-stromal tumor of the kidney is a recently recognized benign renal tumor that usually occurs in adult women and typically forms a sizable lesion with solid and cystic areas. The recognized morphologic spectrum of this recently described entity is evolving.

OBJECTIVE: To review the clinicopathologic features of 3 small mixed epithelial-stromal tumors of the kidney that were incidental findings in kidneys removed for other reasons.

DESIGN: The clinical presentation and morphologic findings of the 3 cases were reviewed. A panel of immunohistochemical stains was performed.

SETTING: Academic medical center.

RESULTS: All 3 lesions contained predominantly fascicles of smooth muscle mimicking leiomyoma, but they also had cellular subpopulations of smaller, mullerian-appearing stromal cells. Tubules present within the lesion were most abundant at the periphery, suggesting that they might be entrapped. Although only the spindled smooth muscle cells were immunoreactive for muscle markers desmin and actin, both the spindled smooth muscle cells and the cellular mullerian-appearing stromal cells demonstrated diffuse nuclear labeling for estrogen and progesterone receptors.

CONCLUSIONS: Mixed epithelial-stromal tumor of the kidney may present as an incidental stromal-predominant lesion within the kidney. Such lesions are easily confused with leiomyomas or stromal-predominant angiomyolipomas.


Prognostic Factors

Rare cases of malignant transformation to a sarcoma

Non-malignant cases may develop progressive renal failure and massive hemorrhage

Malignant Transformation of Renal Angiomyolipoma: A Case Report.

Kawaguchi Ki K, Oda Y, Nakanishi K, Saito T, Tamiya S, Nakahara K, Matsuoka H, Tsuneyoshi M.

Department of Anatomic Pathology (K.-I.K., Y.O., T.S., S.T., M.T.), Pathological Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka, and the Departments of Pathology (K. Nakanishi) and Urology (H.M, K. Nakahara), Aso, Izuka Hospital, Izuka, Japan.

Am J Surg Pathol 2002 Apr;26(4):523-529 Abstract quote

We report a case of renal angiomyolipoma (AML) with malignant transformation. A 28-year-old woman developed large bilateral renal masses 5 months before admission to our hospital.

She was diagnosed with tuberous sclerosis when she was 4 years old. Total nephrectomy of the left kidney was performed, but she died during the operation. Although the focal region of the resected tumor had the appearance of a classic AML, most of the lesion showed a diffuse proliferation of atypical epithelioid cells resembling that in renal cell carcinoma. The epithelioid cells had extremely pleomorphic and hyperchromatic nuclei with frequent mitotic figures, including atypical forms. Immunohistochemical analysis revealed that the atypical epithelioid cells and the typical AML lesions were both positive for HMB-45 but that the former were negative for epithelial and myogenic markers. The smooth muscle cells and thick-walled vessels were focally positive for muscle-specific actins. Furthermore, the atypical epithelioid cells were immunoreactive for p53, whereas the foci of the typical AML were negative. Examination of the microdissected paraffin-embedded tissues revealed p53 mutations in the malignant epithelioid areas in AML but not in the renal parenchyma or typical AML areas.

In this case it is proposed that p53 mutation may play an important role in malignant transformation of renal AML.


Malignant tumors have metastasized to the lung

Rarely new tumors have appeared in the remaining kidney after nephrectomy for a contralateral tumor

Treatment Nephrectomy

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Commonly Used Terms

Extrarenal Angiomyolipoma



Tuberous Sclerosis

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