A renal oncocytoma is a kidney tumour of the kidney made up of , epithelial cell with an excess amount of mitochondria.
Signs and symptoms
Renal oncocytomas are often asymptomatic and are frequently discovered by chance on a CT or
ultrasound of the abdomen. Possible signs and symptoms of a renal oncocytoma include
hematuria, flank pain, and an
abdomen mass.
Pathophysiology
Renal oncocytoma is thought to arise from the intercalated cells of
of the kidney. It represent 5% to 15% of surgically resected
renal . Ultrastructurally, the eosinophilic cells have numerous
mitochondria.
Histologic appearance
An oncocytoma is an
epithelial tumor composed of oncocytes, large
cells having small, round, benign-appearing
Cell nucleus with large
nucleoli and excessive amounts of
mitochondria.
Diagnosis
In gross appearance, the tumors are tan or mahogany brown, well circumscribed and contain a central scar. They may achieve a large size (up to 12 cm in diameter).
The main differential diagnosis of renal oncocytoma is chromophobe renal cell carcinoma oncocytic variant, which like the renal oncocytoma has eosinophilic cytoplasm, but has perinuclear clearing and, typically, some degree of nuclear atypia.
Immunohistochemical profile
[Renal]
Treatment
Renal oncocytoma is considered
benign tumor, cured by
nephrectomy. There are some familial cases in which these tumors are multicentric rather than solitary.
[Robbins pathology, page 1015] However, they may be resected to exclude a malignant tumor, e.g. renal cell carcinoma.
Prognosis
The overall five-year survival rate has been estimated to be 63%, with 100% disease-specific survival.
==Additional images==
of a renal oncocytoma. H&E stain.]]
See also
External links
