Benign cortical cyst of the kidney

Benign cortical cyst of the kidney
Diagnosis in short
Benign cortical renal cyst with papillary projections. H&E stain.
LM	simple epithelial lining without atypia, may have clear cells
LM DDx	localized cystic disease of the kidney, cystic neoplasms/renal cell carcinoma (e.g. cystic clear cell renal cell carcinoma), multicystic renal cell neoplasm of low malignant potential, other cystic kidney diseases
Gross	thin-walled cyst in the renal cortex, usually filled with serous fluid, usually unilocular
Site	kidney - see cystic kidney diseases
Prevalence	very common
Radiology	simple cyst with thin wall; usually Bosniak I or II - see Bosniak classification of renal cysts
Prognosis	benign
Treatment	none

Benign cortical cyst of the kidney is an extremely common benign kidney finding.

Benign renal cyst redirects here. A more general discussion about cysts in the kidney is in the article cystic kidney diseases.

General

• Very common.
• Benign.

Gross

• Thin-walled cyst - usually filled with serous fluid.
• Usually unilocular.

Microscopic

Features:

• Simple epithelial lining without atypia.
• May have clear cells.

Note:

• Do not have clear cells within the wall of the cyst.

DDx:

• Localized cystic disease of the kidney.
• Cystic neoplasms/renal cell carcinoma:
  • Cystic clear cell renal cell carcinoma - thick septa with clear cells.
  • Multicystic renal cell neoplasm of low malignant potential - thin septa, clear cells within stroma.
• Other cystic kidney diseases.

Images

• 

  ARC - very low mag. (WC)

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  ARC - low mag. (WC)

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  ARC - intermed. mag. (WC)

• 

  ARC - intermed. mag. (WC)

• 

  ARC - high mag. (WC)

• 

  ARC - very high mag. (WC)

• 

  ARC - low mag. (WC)

• 

  ARC - intermed. mag. (WC)

• 

  ARC - high mag. (WC)

See also

• Cystic kidney diseases.
• Bosniak classification of renal cysts.
• Benign clear cell clusters of the kidney.