metanephric adenoma

Definition: Metanephric adenoma is a rare benign tumor of the kidney. It is considered to be derived from embryonic renal tissue and to be the benign counterpart of the Wilms tumor. Although its imaging findings and immunohistochemistry are nonspecific, it has a typical microscopic morphology.

Images

 Metanephric adenoma

• WT1/CD57+, AMACR-, opposite IHC of papillary RCC, can be hard to distinguish on bx, CK7++ in pRCC, focal in MA
• https://twitter.com/RyanneMDMBA/status/819746736537120768
• https://twitter.com/WebPathology/status/851903465806864385
• http://www.webpathology.com/case.asp?case=65

 Cards

• https://twitter.com/GeronimoJrLapac/status/947194756957917184

Embryonal (metanephric) adenoma of the kidney, like Wilms’ tumor, exhibits small monomorphic, blue cells arranged as vague, tubular rosettes. Unlike Wilms’ tumor, which requires chemotherapy or multi-modality therapy for optimal management, the available evidence indicates that embryonal adenoma is most likely cured by simple enucleation or nephrectomy.

Immunochemistry

 CDH17+ / cadherin-17+ (25768256)

Variants

 multifocal metanephric adenoma

Cytogenetics

 t(9;15)(p24;q24) (15747102)
 inv(12)(q13q15) (15747102)
 t(1;22)(q22;q13) (16938529)
 t(15;16)(q21;p13) (16938529)

CGH

• lack of DNA copy number changes by high-resolution array CGH (20102400)

See also

 cystic renal tumors

 Tumors

• renal tumors
  • metanephric adenofibroma

References

 Cadherin 17 is a sensitive and specific marker for metanephric adenoma. Yakirevich E, Magi-Galluzzi C, Grada Z, Lu S, Resnick MB, Mangray S. Am J Surg Pathol. 2015 Apr;39(4):479-86. doi : 10.1097/PAS.0000000000000401 PMID: 25768256

 High-resolution array CGH of metanephric adenomas: lack of DNA copy number changes. Szponar A, Yusenko MV, Kovacs G. Histopathology. 2010 Jan;56(2):212-6. PMID: 20102400

 Lerut E, Roskams T, Joniau S, Oyen R, Achten R, Van Poppel H, Debiec-Rychter M. Metanephric adenoma during pregnancy: clinical presentation, histology, and cytogenetics. Hum Pathol. 2006 Sep;37(9):1227-32. PMID: 16938529

 Rakheja D, Lian F, Tomlinson GE, Ewalt DH, Schultz RA, Margraf LR. Renal metanephric adenoma with previously unreported cytogenetic abnormalities: case report and review of the literature. Pediatr Dev Pathol. 2005 Mar-Apr;8(2):218-23. PMID: 15747102

 Muir TE, Cheville JC, Lager DJ. Metanephric adenoma, nephrogenic rests, and Wilms’ tumor: a histologic and immunophenotypic comparison. Am J Surg Pathol. 2001 Oct;25(10):1290-6. PMID: 11688464

 Renshaw AA, Freyer DR, Hammers YA. Metastatic metanephric adenoma in a child. Am J Surg Pathol. 2000 Apr;24(4):570-4. PMID: 10757405

 Zafar N, Spencer D, Berry AD 3rd. Embryonal adenoma of the kidney: a report of two cases. Diagn Cytopathol. 1997 Jan;16(1):42-6. PMID: 9034736

 Davis CJ Jr, Barton JH, Sesterhenn IA, Mostofi FK.Metanephric adenoma. Clinicopathological study of fifty patients.Am J Surg Pathol. 1995 Oct;19(10):1101-14. PMID: 7573669

 Jones EC, Pins M, Dickersin GR, Young RH. Metanephric adenoma of the kidney. A clinicopathological, immunohistochemical, flow cytometric, cytogenetic, and electron microscopic study of seven cases. Am J Surg Pathol. 1995 Jun;19(6):615-26. PMID: 7755148