Table of Contents
Definition / general | Clinical features | Case reports | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Negative stains | Electron microscopy description | Differential diagnosisCite this page: Roychowdhury M. Sebaceous. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/breastmalignantsebaceouscarcinoma.html. Accessed July 6th, 2022.
Definition / general
- Very rare primary breast carcinoma resembling skin adnexal tumor with sebaceous differentiation, but no evidence of cutaneous derivation (see J Med Case Rep 2008;2:276 for cutaneous tumor of breast)
Clinical features
- Associated with Muir-Torre syndrome (Cancer 2005;103:1018)
Case reports
- 45 year old woman with extensive metastatic disease (Pathol Int 2000;50:63)
- 46 year old woman with Muir-Torre syndrome (AJR Am J Roentgenol 2000;174:541)
- 50 year old woman (Pathol Int 2009;59:188)
- 63 year old woman (Virchows Arch 2006;449:484)
- 83 year old woman with tumor of nipple (J Cutan Pathol 2008;35:608)
Microscopic (histologic) description
- Well defined solid sheets or lobules of atypical epithelial cells, including large, pale or clear cells with coarsely vacuolated cytoplasm, containing Oil red O staining lipid and often scalloped nuclei
- Often focal squamous morules
Microscopic (histologic) images
Positive stains
- Cytokeratin, including 35betaH11 (Pathol Res Pract 1993;189:888), EMA
- ER, PR, Oil Red O
- Mismatch repair genes: MLH1, PMS2, MSH2, MSH6 (Ceska Gynekol 2010;75:50)
- Some cells may express neuroendocrine markers
Negative stains
- GCDFP-15, CEA, S100 and vimentin
- Alpha smooth muscle actin, p63, androgen receptor (usually), mucins, HER2 and CK15
Electron microscopy description
- Empty appearing, non membrane bound vacuoles
Differential diagnosis
- Apocrine carcinoma: > 90% of tumor cells have cytologic or immunohistochemical features of apocrine cells
- Lipid rich carcinoma: usually not coarsely vacuolated, often squamous morules, usually HER2+, ER-, PR-