Myoepithelial Carcinoma of the Breast
Malignant myoepithelioma; Metaplastic carcinoma; Spindle cell carcinoma
A malignant lesion composed of myoepithelial cells with increased mitotic activity and expression of myoepithelial markers, such as high molecular weight cytokeratins, p63, smooth muscle actin, and others.
Myoepithelial carcinomas of the breast represent an extremely rare and poorly understood entity of invasive breast cancer. The exact incidence of these tumors is unknown, partially due to the disputed definition. According to the actual WHO classification, myoepithelial carcinomas are a subgroup of metaplastic carcinoma (Reis-Filho et al. 2012). Under these assumptions, the incidence is probably significantly lower than <1%.
Myoepithelial carcinomas have been seen in all age groups from 25 to 81 years.
Rare cases of myoepithelial carcinoma of the breast have been described in women. The incidence in male patients is not known.
A predominant site within...
References and Further Reading
- Reis-Filho, J. S., Lakhani, S. R., Gobbi, H., & Sneige, N. (2012). Metaplastic carcinoma. In S. R. Lakhani, I. O. Ellis, S. J. Schnitt, P. H. Tan, & M. J. van de Vijver (Eds.), WHO classification of tumours of the breast (pp. 119–124). IACR: Lyon.Google Scholar
- Schmitt, F., Tan, P. H., Dabbs, D., & Jones, L. (2012). Myoepithelial and epithelial–myoepithelial lesions. In S. R. Lakhani, I. O. Ellis, S. J. Schnitt, P. H. Tan, & M. J. van de Vijver (Eds.), WHO classification of tumours of the breast (pp. 119–124). IACR: Lyon.Google Scholar
- Schnitt, S. J., & Collins, L. C. (2009). Spindle cell lesions. In S. J. Schnitt (Ed.), Biopsy interpretation of the breast (pp. 323–343). Philadelphia: Lippincott Williams & Wilkins.Google Scholar
- Tavassoli, F. A., & Eusebi, V. (2009). Myoepithelial lesions. In F. A. Tavassoli & V. Eusebi (Eds.), Tumors of the mammary gland (pp. 249–262). Washington, DC: Armed Forces Institute of Pathology.Google Scholar