Oncocytic Carcinoma of the Breast
Definition
- Breast carcinoma with abundant eosinophilic cytoplasm due to large numbers of mitochondria
Alternate / Historical Names
- Malignant oncocytoma
- Mammary epithelial oncocytoma
Diagnostic Criteria
- Only four cases reported
- Unrecognized cases may have been called apocrine carcinoma
- Indistinguishable from apocrine carcinoma on H&E stain
- Abundant granular cytoplasm
- Sharp cell borders
- Large round nuclei with prominent nucleoli
- Immunohistologically differs from apocrine carcinoma
- GCDFP15 negative
- Antimitochondrial antibody positive
- May be in situ or invasive
Richard L Kempson MD
Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342
Original posting:: May 15, 2006