ADENOMYOEPITHELIOMA

ADENOMYOEPITHELIOMA

• Adenomyoepithelioma is a tumor composed of proliferating myoepithelial cells surrounding epithelial lined ducts.

Clinical features  

• Females with age range of 26 to 82 years (rarely in male breast)
• Presents as palpable lump
• Mammography – well circumscribed density with microcalcifications

Gross findings

• sharply circumscribed tumors with size ranging from 1 to 10cms
• Cut surface – tan to pink with cystic or papillary structures
• Consistency – firm to rubbery
• Presents as solitary mass with satellite nodules

Microscopic features  

• Encapsulated to well lineated tumor characterized by sheets of proliferating myoepithelial cells around ductal spaces lined by epithelial cells
• The tumor may display variable patterns like –
• Spindle cell pattern – solid proliferation of spindled myoepithelial cells surrounding the ductal spaces sometimes totally compressing the ducts
• Tubular variant – this lesion is ill defined , lacking encapsulation and composed of collection of tubule lined by benign epithelial cells surrounded by myoepithelial cells. upto 3 mitptic figures /10hpf may be seen.
• Lobulated variant – In this variant partial to complete thick fibrous capsule is present. The lesion is composed of solid nests of myoepithelal  cells having clear to eosinophilic /amphophilic cytoplasm. fibrous septa of varying thickness separates the lobules. Hyaline degeneration, infarction, calcifications can be seen

Epithelial, myoepithelial or both the components can give rise to malignancy in malignant adenomyoepithelioma.

Prognosis

• Tumor with tubular pattern show multiple recurrences
• Malignant adenomyoepitheliomas are low grade malignancy metastasizing tom lungs. Rarely metastasis can also occur brain, jaws and lymph nodes.

Treatment

• Wide complete excision of tumor.