Recurrent intrathoracic dedifferentiated liposarcoma: A case report and literature review

Liposarcoma (LPS) is the second most common type of soft tissue sarcoma, accounting for approximately 15-20% of all the sarcomas. Primary intrathoracic LPS, however, is quite rare. LPS is a malignant mesenchymal tumor, comprised of lipogenic tissue with varying degrees of atypia. It can be subclassified into well-differentiated LPS (WDLPS), myxoid LPS (MLPS)/round cell LPS, pleomorphic LPS (PLPs), and dedifferentiated LPS (DDLPS), based on the histology.

A 76-year-old male patient initially presented to the emergency room with a complaint of precordial chest pain for one month. Computed tomography (CT) of his chest showed a large, 8 cm × 8 cm x 10 cm, supradiaphragmatic, complex solid mass in the lower left hemithorax, along the anterior chest wall. Chest wall mass excision revealed dedifferentiated LPS, with excision of margins. Positron emission tomography (PET) scan did not show metastatic disease. Seven months later, he presented with shortness of breath, and CT of the chest showed large, left pleural-based masses, causing compression of surrounding structures. He was not a candidate for surgical resection. This patient subsequently failed chemotherapy and opted for hospice.

Intrathoracic LPS is a rare tumor. Recurrence is higher with dedifferentiated histology forms. Radical surgery with excision of margins is the primary recommended treatment.