Transcript Clear Cell Sarcoma of the Kidney (CCSK)

CPC #3
Pathology
Radical Nephrectomy
• Three intrarenal masses with cystic change
(9, 7, and 5cm)
• Nodular Mass (3cm) in perirenal fat
Not all Renal Tumors (Masses)
are Renal Cell Carcinoma!
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Angiomyolipoma
Oncocytoma
Xanthogranulomatous Pyelonephritis
Malakoplakia
Adrenal Rest
Xanthogranulomatous Pyelonephritis
• Subacute/chronic inflammation forming a
mass lesion in the kidney
• Tender unilateral flank mass
• Nephrolithiasis (70%)
– Long term recurrent obstruction
• Adults
• Female Predominance (2:1)
Xanthogranulomatous Pyelonephritis
• Gross:
– yellow mass often extending into perirenal fat,
mimicking renal cell carcinoma
• Microscopic:
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Lipid-laden macrophages
Fibroblastic proliferation
Lymphocytes, plasma cells
Microabscesses
• Microbiology:
– Often Proteus mirabilis, E. Coli
CD68
Diagnosis
Xanthogranulomatous Pyelonephritis
ACID-FAST STAIN
ACID-FAST STAIN
Diagnosis
• Xanthogranulomatous Pyelonephritis
• Numerous Acid-fast Bacilli
Similar Cases in Literature
• Shah HN et al. Renal tuberculosis simulating
xanthogranulomatous pyelonephritis with
contagious hepatic involvement. Int J Urology
2006;13: 67-68.
• Izbudak-Oznur et al. Renal tuberculosis
mimicking xanthogranulomatous pyelonephritis:
ultrasonography, computed tomography and
magnetic resonance imaging findings. Turk J
Pediatr 2002;44: 168-171
Important Point
• Immunocompromised patients often do not
form granulomas well
• One may see Mycobacterial or Fungal
Infections without well-formed granulomas