From the archives of the AFIP: Pleuropulmonary synovial sarcoma.

Pleuropulmonary synovial sarcoma (PPSS) is increasingly recognized as a subtype of sarcoma because of the recent identification of a distinctive chromosomal translocation specific to synovial sarcoma. Soft-tissue synovial sarcoma is far more common than PPSS and typically develops in para-articular locations of the extremities; affects young and middle-aged adults, with no difference in distribution between the sexes; and has well-documented radiologic manifestations. PPSS may arise in the chest wall, heart, mediastinum, pleura, or lung, and it shares patient demographics and several imaging features with its soft-tissue counterpart. Patients present with a cough, chest pain, or dyspnea. On chest radiographs, PPSS typically appears as a sharply marginated mass with uniform opacity, based either in the pleura or in the lung, and often accompanied by an ipsilateral pleural effusion. Computed tomographic images show a well-circumscribed heterogeneously enhanced lesion without associated involvement of bone and without calcifications (except in the case of a chest wall primary tumor). Magnetic resonance imaging provides superior demonstration of nodular soft tissue and multilocular fluid-filled internal components of PPSS, in addition to peripheral rim enhancement after the intravenous administration of a gadolinium-based contrast material such as gadopentetate dimeglumine. Current treatment consists of surgical resection followed by chemotherapy, radiation therapy, or both.