Difference between revisions of "Pediatric kidney tumours"

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(→‎Wilms tumour: split out)
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==Wilms tumour==
==Wilms tumour==
*[[AKA]] nephroblastoma, AKA Wilms' tumour.
*[[AKA]] nephroblastoma, AKA Wilms' tumour.
 
{{Main|Wilms tumour}}
===General===
*Common abdominal [[pediatric pathology|pediatric]] tumour.
*May be associated with a syndrome:<ref>URL: [http://emedicine.medscape.com/article/989398-overview http://emedicine.medscape.com/article/989398-overview]. Accessed on: 9 March 2011.</ref>
**WAGR syndrome (Wilms tumour, Aniridia (absence of iris), GU abnormalities, Retardation).<ref>{{OMIM|194072}}</ref>
**[[Beckwith-Wiedemann syndrome]].<ref>{{OMIM|130650}}</ref>
**[[Denys-Drash syndrome]].<ref>{{OMIM|194080}}</ref>
 
===Gross===
*Lobulated tan mass.
 
Image: [http://library.med.utah.edu/WebPath/EXAM/IMGQUIZ/rnfrm.html Wilms tumour (med.utah.edu)].
 
===Microscopic===
Features - classically three components (blastema, immature stroma, tubules):<ref name=Ref_PCPBoD8_254-5>{{Ref PCPBoD8|254-5}}</ref>
#Malignant [[Small round blue cell tumours|small round blue cells]] ("blastema"):
#*Size = ~ 2x RBC diameter.
#*Nuclear pleomorphism (variation of size, shape and staining).
#**Irregular nuclear membrane - '''important'''.
#*Scant/difficult to discern cytoplasm - basophilic (light blue).
#*Mitoses - common.
#Stroma ("immature stroma"):
#*Spindle cells:
#**Elliptical nuclear membrane.
#**Abundant loose cytoplasm.
#Tubular structures ("tubules"):
#*Usually clustered.
#*Vaguely resemble a glomerulus.
#*Usu. have a central (clear/white) space surrounded by a rim of intensely eosinophilic cytoplasm.
#*Nuclei of tubular structures often elongated and palisaded.
 
Other findings:
*Commonly seen in association with ''nephrogenic rests''.
**Cluster of cells small (blue) cells; lack nuclear atypia seen in Wilms tumour.<ref>URL: [http://www.pathconsultddx.com/pathCon/diagnosis?pii=S1559-8675%2806%2970416-8 http://www.pathconsultddx.com/pathCon/diagnosis?pii=S1559-8675%2806%2970416-8]. Accessed on: 28 March 2011.</ref>
*+/-Heterologous elements (skeletal muscle, smooth muscle adipose tissue, cartilage).<ref name=Ref_WMSP282>{{Ref WMSP|282}}</ref>
**Heterologous = doesn't normally belong there.<ref>URL: [http://www.biology-online.org/dictionary/Heterologous http://www.biology-online.org/dictionary/Heterologous]. Accessed on: 1 October 2011.</ref>
 
DDx:
*[[Metanephric adenoma]].
*Nephrogenic nests.
*Other [[small round cell tumours]].
*[[Synovial sarcoma]], biphasic - especially in adults.
 
Notes:
*Palisade = fence made of stakes driven into the ground.<ref>URL: [http://www.thefreedictionary.com/palisaded http://www.thefreedictionary.com/palisaded]. Accessed on: 2 February 2011.</ref>
*Approximately 30-40% Wilms tumour cases have nephrogenic rests.<ref name=pmid8047084>{{cite journal |author=Coppes MJ, Haber DA, Grundy PE |title=Genetic events in the development of Wilms' tumor |journal=N. Engl. J. Med. |volume=331 |issue=9 |pages=586–90 |year=1994 |month=September |pmid=8047084 |doi=10.1056/NEJM199409013310906 |url=}}</ref>
*The three phases are also called ''blastemal, epithelial and stromal''.<ref name=Ref_WMSP282>{{Ref WMSP|282}}</ref>
 
====Images====
<gallery>
Image:Wilms_tumour_-_low_mag.jpg | Wilms tumour - low mag. (WC/Nephron)
Image:Wilms tumour - intermed mag.jpg | Wilms tumour - intermed. mag. (WC/Nephron)
Image:Wilms tumour - high mag.jpg | Wilms tumour - high mag. (WC/Nephron)
Image:Wilms_tumour_-_very_high_mag.jpg | Wilms tumour - very high mag. (WC/Nephron)
</gallery>
www:
*[http://www.biologydisease.com/images/kidney/nephrogenic-rests/nephrogenic-rest.jpg.php Nephrogenic rests (biologydisease.com)].
*[http://www.webpathology.com/image.asp?n=1&Case=73 Wilms tumour (webpathology.com)].
 
====Anaplasia====
Subclassified as:<ref name=Ref_WMSP282>{{Ref WMSP|282}}</ref>
#Focal anaplasia.
#Diffuse anaplasia.
 
Criteria (all of the following):<ref name=Ref_WMSP282>{{Ref WMSP|282}}</ref>
#Atypical mitoses.
#Nuclear hyperchromasia.
#Nuclear size variation (of the tumour cells) > 3x.
 
===IHC===
*WT-1 +ve.


==Metanephric stromal tumour==
==Metanephric stromal tumour==

Revision as of 03:16, 3 May 2014

This article cover pediatric kidney tumours. Adult kidney tumour are covered in kidney tumours article. An introduction to pediatric pathology is in the pediatric pathology article.

Overview

These are diagnoses pediatric pathologists make.

The most common ones are:

  1. Wilms tumour.
  2. Clear cell sarcoma of the kidney.

Other renal tumours (not covered in this article):

The translocation carcinomas are covered in the kidney tumours article

Specific tumours

Wilms tumour

  • AKA nephroblastoma, AKA Wilms' tumour.

Metanephric stromal tumour

  • Abbreviated MST.

General

Gross

Features:[1]

  • Usu. renal medulla.
  • Solid or cystic.

Microscopic

Features:[1]

  • "Collarettes" - tumour cells surround blood vessels or renal tubules.
  • Spindle cells/stellate cells.
  • Variable cellular density - imparts a nodular appearance at low power.
  • Indistinct cell borders/cytoplasm.
  • Induces epithelioid morphology in smooth muscle cells.

Notes:

  • +/-Heterologous elements.

DDx:

Images:

Metanephric adenofibroma

General

  • Adults and children.

Microsopic

Features:[1]

Mesoblastic nephroma

General

  • Almost exclusively in infants.

Subclassified:

  1. Classic.
  2. Cellular.
  3. Mixed.

Gross

  • Renal sinus infiltration - common.

Microscopic

Classic

Features:[3]

  • Spindle cells in fascicles.
  • Infiltrative border.

Cellular

Features:[3]

  • Plump cells with vesicular nuclei.
  • Well-defined border.
  • Mitotically active.

Mixed

  • Like the name implies - both classic pattern and cellular pattern areas are present.[3]

Molecular

Cellular mesoblastic nephroma:

Clear cell sarcoma of the kidney

General

  • Common pediatric renal tumour - second only to Wilms tumour.
  • Aggressive.

Gross

  • Renal medulla.
  • +/-Cystic.

Image:

Microscopic

Features:[3]

  • Polygonal cells/Stellate cells.
  • Indistinct cell borders/cytoplasm; clear background.
  • No nucleoli.

Images:

IHC

Features:[4]

  • Vimentin +ve.
  • Desmin -ve.
  • Smooth muscle actin -ve.
  • NSE -ve.
  • S-100 -ve.

Renal rhabdoid tumour

  • AKA rhabdoid tumour of the kidney, abbreviated RTK.

General

Microscopic

Features:[5][3]

  • Variable architecture.
  • Round cells.
  • Abundant cytoplasm with eosinophilic inclusions.
  • Eccentric vesicular nucleus.
  • Prominent nucleolus -- key feature.

Images:

IHC

  • INI1 -ve.

Renal cell carcinoma

General

Papillary RCC

See: (adult) renal cell carcinoma.
  • Most common form of RCC in children.

Clear cell RCC

See: (adult) renal cell carcinoma.

See also

References

  1. 1.0 1.1 1.2 1.3 Humphrey, Peter A; Dehner, Louis P; Pfeifer, John D (2008). The Washington Manual of Surgical Pathology (1st ed.). Lippincott Williams & Wilkins. pp. 283. ISBN 978-0781765275.
  2. 2.0 2.1 Palese, MA.; Ferrer, F.; Perlman, E.; Gearhart, JP. (Sep 2001). "Metanephric stromal tumor: a rare benign pediatric renal mass.". Urology 58 (3): 462. PMID 11549506.
  3. 3.0 3.1 3.2 3.3 3.4 3.5 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.
  4. Viswanathan, S.; Dave, BK.; Desai, SB. (Apr 2007). "Clear cell sarcoma of the kidney--a study of seven cases over a period of three years.". Indian J Pathol Microbiol 50 (2): 270-3. PMID 17883043.
  5. Humphrey, Peter A; Dehner, Louis P; Pfeifer, John D (2008). The Washington Manual of Surgical Pathology (1st ed.). Lippincott Williams & Wilkins. pp. 627. ISBN 978-0781765275.