Oncocytoma Classification and external resources
Micrograph of a renal oncocytoma. H&E stain.
ICD-O: M8290/0 DiseasesDB 31956 eMedicine med/1045 MeSH D018249
An oncocytoma is an epithelial tumor composed of oncocytes, large eosinophilic cells having small, round, benign-appearing nuclei with large nucleoli.
Oncocytoma can arise in a number of organs.
Salivary gland oncocytoma
The salivary gland oncocytoma is a well-circumscribed, benign neoplastic growth also called an oxyphilic adenoma. It comprises about 1% of all salivary gland tumors. The histopathology is marked by sheets of large swollen polyhedral epithelial oncocytes, which are granular acidophilic parotid cells with centrally located nuclei. The granules are created by the mitochondria.
Salivary gland oncocytomas are most common in ages 70-80, females, the parotid gland (85-90%), and are firm, slowly growing, painless masses of < 4 cm. They may be bilateral.
Thyroid oncocytomas can be benign (adenomas) or malignant (carcinomas). Grossly, oncocytic adenomas are encapsulated, solid nodules with a characteristic brown cut surface. The gross appearance of a minimally invasive oncocytic carcinoma is indistinguishable to that of an adenoma, while widely invasive oncocytic carcinomas are obviously invasive macroscopically and display pervasive vascular invasion with multifocal involvement of the thyroid gland. There are no reliable cytologic features which distinguish oncocytic adenomas from carcinomas and the only criteria for a diagnosis of malignancy is the identification of transcapsular and/or vascular invasion.
Patients with thyroid oncocytomas present with a thyroid nodule, usually with normal thyroid function. If the tumor is big or invasive, there may be other symptoms such as difficulty swallowing or talking.
- ^ Coburn V, Radfar A, Snook D, Mahalingam M (2007). "Cutaneous oncocytoma - a report of three cases and review of the literature". J. Cutan. Pathol. 34 (4): 355–9. doi:10.1111/j.1600-0560.2006.00620.x. PMID 17381809. http://www.blackwell-synergy.com/openurl?genre=article&sid=nlm:pubmed&issn=0303-6987&date=2007&volume=34&issue=4&spage=355.
- ^ "Atlas of Genetics and Cytogenetics in Oncology and Haematology - Thyroid:oncocytic tumors". http://atlasgeneticsoncology.org/Tumors/OncocytThyroidID5068.html. Retrieved 2009-02-01.
Glandular and epithelial neoplasms (ICD-O 8010-8589) Epithelium GlandsOther/multipleAdnexal and
skin appendage (8390-8429)Cystic, mucinous,
and serous (8440-8499)Cystic generalSerousDuctal, lobular,
and medullary (8500-8549)Lobular carcinoma in situ · Invasive lobular carcinomaAcinar cell (8550-8559)
OtherComplex epithelial (8560-8589)see also Template:Epithelium and epithelial tissue Tumors of lip, oral cavity and pharynx / head and neck cancer (C00–C14/D10–D11, 140–149/210) Oral cancer Tumors: urogenital neoplasia: urinary organs (C64–C68/D30, 188–189/223) AbdominalKidneyGlandular and epithelial neoplasm: Renal cell carcinoma · Renal oncocytomaComplex and mixed tumor: Wilms' tumor · Mesoblastic nephroma · Clear-cell sarcoma of the kidney · Angiomyolipoma · Cystic nephroma · Metanephric adenomaby location: Renal medullary carcinoma · Juxtaglomerular cell tumor · Renal medullary fibromaUreter Pelvic Retroperitoneum
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