J Korean Surg Soc.  2002 Jul;63(1):74-78.

A Case of Myoepithelial Carcinoma of the Breast

• Shin SY
• Oh SJ
• Park WC
• Kim JS
• Chang ED
• Jung SS

Abstract

A 42-year-old woman presented with a mass in the lower inner quadrant of the left breast that had been present for about 1 month. The mass was irregular in shape and rubbery in consistency, and measured 2 1.5 cm. It appeared well-demarcated, with a high density mass shadow on the mammogram. Lumpectomy was performed, with a 2 cm safety margin surrounding the tumor mass, with simultaneous ipsilateral axillary dissection. The tumor was diagnosed from its histology and immunohistochemistry as a myoepithelial carcinoma, in which the tumor cells were immunoreactive for the epithelial membrane antigen (EMA), smooth muscle actin and S-100 protein. These proteins are not specific to myoepithelial cells, but in combination, positive findings indicate myoepithelial differentiation. Most myoepithelial tumors of the breast are benign. However, invasive breast tumors, showing myoepithelial cell differentiation, are rare and usually give rise to metastases. She had received postoperative radiotherapy, and local recurrence and distant metastasis have not occurred so far. Here, we present a case of myoepithelial carcinoma of the breast, with a review of the literatures.

Keyword

Breast; Myoepithelial carcinoma

MeSH Terms

Actins
Adult
Breast Neoplasms
Breast*
Cell Differentiation
Female
Humans
Immunohistochemistry
Mastectomy, Segmental
Mucin-1
Muscle, Smooth
Myoepithelioma
Neoplasm Metastasis
Radiotherapy
Recurrence
S100 Proteins
Actins
Mucin-1
S100 Proteins