Primary malignant fibrous histiocytoma of the diaphragm: report of a case.

We present herein the case of a 55-year-old man with primary malignant fibrous histiocytoma (MFH) of the diaphragm. He was admitted to our hospital with right anterior chest pain, where diagnostic imaging showed a huge tumor in the right diaphragm with a tumor thrombus in the vena cava, spreading to the left lobe of the liver and the pericardium. Although invasion into the right lung was identified at the time of surgery, the entire tumor was removed. Histopathological examination of the resected specimen revealed the characteristics of MFH. We discuss the clinical features of this patient in comparison with the few previous reports on MFH of the diaphragm.