Malignant mesenchymoma of the pleura.

Malignant mesenchymomas are rare soft tissue tumors of mesenchymal origin. We report a case of pleural localization with liposarcomatous, leiomyosarcomatous and osteocartilaginous elements. The treatment associated surgical resection, chemotherapy and radiotherapy. Sixteen months after the diagnosis a metastatic retroperitoneal sarcoma with osteosarcomatous differentiation appeared without any sign of thoracic recurrence. A surgical resection was performed, but a rapid retroperitoneal recurrence led to death.