Primary epithelioid leiomyosarcoma of the endothoracic fascia

The case we describe is, to our knowledge, the first primary epithelioid leiomyosarcoma of the endothoracic fascia reported in the literature. The endothoracic fascia is localized between the costal parietal pleura and the inner face of the thoracic wall and contains connective, adipose, smooth muscular tissues, lymphoid aggregates and vessels. Malignant tumors of the endothoracic fascia are difficult to identify because they quickly infiltrate the lung, the chest wall and the mediastinum. When discovered, these tumors are classified as primary soft tissue sarcomas of these sites. In the present case, early diagnosis of an asymptomatic lesion allowed us to establish its origin in the endothoracic fascia. The CT characteristics suggested a non-aggressive lesion, with clearly defined profiles and without signs of infiltration of the adjacent lung, fat and cartilages. Histological differential diagnosis and role of radiology in the management of the case are discussed. As radiological techniques spread and improve, we expect the diagnosis of endothoracic fascia primary tumors could become more frequent.