Renal oncocytosis

Renal oncocytosis
Diagnosis in short
LM DDx	other renal tumours with eosinophilic cytoplasm
IHC	characteristic of the histologic appearance - stain like oncocytoma, ChRCC and hybrid tumour
Gross	multiple brown kidney nodules (bilateral or unilateral)
Grossing notes	total nephrectomy for tumour grossing, partial nephrectomy grossing
Staging	kidney tumour staging
Site	kidney - see kidney tumours
Syndromes	Birt–Hogg–Dubé syndrome
Clinical history	+/-chronic renal failure and hemodialysis
Prevalence	rare
Radiology	multiple renal tumours
Clin. DDx	metastatic disease, multifocal renal cell carcinoma

Renal oncocytosis is the presence of multiple oncocytic lesions within the kidney.

General

• Rare.
• May be seen in the context of Birt–Hogg–Dubé syndrome or chronic renal failure or may be sporadic.

Gross

• Multiple (unilateral or bilateral) brown-coloured nodules.

Microscopic

Features:

• Any mixture of oncocytic tumours (hybrid tumour, chromophobe renal cell carcinoma, renal oncocytoma).

DDx:

• Hybrid tumour.
• Chromophobe renal cell carcinoma.
• Renal oncocytoma.
• Other renal tumours with eosinophilic cytoplasm.

IHC

• Characteristic of the histologic appearance.
• Stain like renal oncocytomas, chromophobe renal cell carcinomas and hybrid tumours.

See also

• Renal tumours.