MALIGNANT MIXED TUMOR

 

 

 

Epidemiology.

Malignant mixed tumor presents in middle-aged adults, most commonly in women.

 

Etiology.

This malignant counterpart of benign mixed tumor appears mainly to develop de novo.

 

Clinical Findings.

Malignant mixed tumor shows predilection for the trunk and extremities, anatomic sites not usually involved by benign mixed tumors. It appears as a solitary, occasionally painful, firm or cystic, non-ulcerated cutaneous or subcutaneous nodule measuring 2 to 10 cm in diameter

 

Histopathology.

The tumor shows lobulated epithelial aggregations with tubular structures, cords, and solid elements. The epithelial component is surrounded by a fibrous stroma with myxomatous and cartilaginous areas. Neoplastic cells display polygonal, plasmacytoid, or cuboidal appearances with variable pleomorphism and scattered mitotic figures. Tubular structures show either apocrine or eccrine differentiation.

 

Treatment.

 Treatment of choice is total surgical excision. Local and distant metastases, especially to lymph nodes, are common. Prophylactic removal of regional lymph node chains and/or adjuvant radiotherapy may facilitate long-term survival