Metanephric adenoma
| Metanephric adenoma | |
|---|---|
| Diagnosis in short | |
 Metanephric adenoma. H&E stain. | |
|
| |
| LM | small uniform cells with fine chromatin, no apparent nucleolus, and a relatively smooth nuclear membrane; variable architecture - may be sheets or ductal |
| LM DDx | Wilms tumour, papillary renal cell carcinoma (type 1) |
| IHC | WT-1 +ve, CD57 +ve, AMACR -ve, CD56 -ve |
| Site | kidney - see kidney tumours |
|
| |
| Clinical history | usu. adults, occasionally children |
| Prevalence | uncommon |
| Prognosis | good, benign |
Metanephric adenoma is a benign tumour of the kidney.
It should not be confused mesonephric adenoma, another term for nephrogenic adenoma.
This can be remembered as follows: metanephric adenoma is a tumour.
General
- Benign.
- Afflicts adults and occasionally children.
- May be associated with polycythemia.[1]
Microscopic
Features:[2]
- Small uniform cells with:
- Fine chromatin.
- No apparent nucleolus.
- A relatively smooth nuclear membrane.
- Variable architecture - may be sheets or ductal.
- +/-Psammoma bodies.
DDx:
- Epithelioid nephroblastoma (Wilms tumour) - these typically have:
- Irregular nuclear membrane.
- Nucleoli.
- Mitoses (rare in metanephric adenoma).
- Papillary RCC.[2]
- Other small round cell tumours, e.g. small cell carcinoma.
Images
Metanephric adenoma (WC/Nephron)
Metanephric adenoma - cropped (WC/Nephron)
Metanephric adenoma - PaRCC-like - low mag. (WC/Nephron)
Metanephric adenoma - PaRCC-like - intermed. mag. (WC/Nephron)
Metanephric adenoma - PaRCC-like - very high mag. (WC/Nephron)
Metanephric adenoma - PaRCC-like - very high mag. (WC/Nephron)
www:
IHC
- WT-1 +ve.[3]
- CD57 +ve.[3]
- AMACR -ve.[3]
- CD56 -ve.[4]
- Positive in Wilms tumour[4] and small cell carcinoma.
- CK7 +ve (focal).[4]
- TTF-1 -ve.[citation needed]
Sign out
Left kidney, total nephrectomy: - Metanephric adenoma, see comment. COMMENT: The tumour stains as follows: POSITIVE: WT1, CD57, PAX8. NEGATIVE: CD56, TTF-1, AMACR.
See also
References
- ↑ Le Nué, R.; Marcellin, L.; Ripepi, M.; Henry, C.; Kretz, JM.; Geiss, S. (Aug 2011). "Conservative treatment of metanephric adenoma. A case report and review of the literature.". J Pediatr Urol 7 (4): 399-403. doi:10.1016/j.jpurol.2010.09.010. PMID 21220212.
- ↑ 2.0 2.1 Humphrey, Peter A; Dehner, Louis P; Pfeifer, John D (2008). The Washington Manual of Surgical Pathology (1st ed.). Lippincott Williams & Wilkins. pp. 284. ISBN 978-0781765275.
- ↑ 3.0 3.1 3.2 Watanabe, S.; Naganuma, H.; Shimizu, M.; Ota, S.; Murata, S.; Nihei, N.; Matsushima, J.; Mikami, S. et al. (2013). "Adult nephroblastoma with predominant epithelial component: a differential diagnostic candidate of papillary renal cell carcinoma and metanephric adenoma-report of three cases.". Case Rep Pathol 2013: 675875. doi:10.1155/2013/675875. PMID 24083046.
- ↑ 4.0 4.1 4.2 Muir, TE.; Cheville, JC.; Lager, DJ. (Oct 2001). "Metanephric adenoma, nephrogenic rests, and Wilms' tumor: a histologic and immunophenotypic comparison.". Am J Surg Pathol 25 (10): 1290-6. PMID 11688464.
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