Malignant Fibrous Histiocytoma Accompanying Hemorrhage in the Pleural Cavity

Malignant fibrous histiocytoma is a type of soft tissue tumor that frequently occurs in the limbs, trunk, retroperitoneum, etc. We herein report a case of MFH occurring in the thoracic wall, which was accompanied by hemorrhage in the pleural cavity. A 79-year-old male transferred to our hospital for a detailed examination of a chest wall tumor in his right back. The tumor was diagnosed as pleomorphic malignant fibrous histiocytoma (MFH) by an incisional biopsy. Before the scheduled operation, the patient developed right upper abdominal pain. A CT, blood test and pleural puncture revealed that the patient had a massive hemothorax, which required emergency surgery. The eighth, ninth and tenth ribs and intercostal muscles, along with the seventh intercostal muscle, were resected, which enabled the tumor to be completely removed. MFH originating in the thoracic wall is rare; but it is important to be aware of the risk of hemothorax when MFH is exposed directly to the pleural cavity.