Giant Dedifferentiated Liposarcoma of the Mediastinum

Soft tissue sarcomas are rare, accounting for only 1% of adult malignancies, with liposarcoma being a common subtype. However, mediastinal liposarcomas are extremely uncommon, comprising less than 1% of cases. Dedifferentiated liposarcoma (DDLPS) is a particularly aggressive variant, characterized by a transition from well-differentiated to high-grade non-lipogenic sarcoma. Due to its rarity and often asymptomatic nature until significant progression, mediastinal DDLPS presents a unique diagnostic and therapeutic challenge.

An 83-year-old woman with ischemic heart disease presented with progressive dyspnea over two months. Imaging revealed a giant, well-circumscribed mediastinal mass (21 × 23 × 25 cm), occupying 80% of the thoracic cavity and causing significant pulmonary compression and mediastinal shift. A multidisciplinary tumor board recommended surgical resection.

Initial uniportal video-assisted thoracic surgery exploration confirmed no pleural invasion. This was followed by a posterolateral thoracotomy for complete tumor excision. The patient recovered without complications. Histopathology confirmed DDLPS with complex histological architecture, including both well-differentiated and dedifferentiated sarcomatous components. The patient is disease-free three years postoperatively.

Our case report emphasizes the requirement of a multidisciplinary approach to treat massive chest malignancy. Complete surgical resection remains the gold standard to obtain long-term survival.