Primary malignant fibrous histiocytoma of spleen with spontaneous rupture: a case report and literature review.

Malignant fibrous histiocytoma (MFH) is the most common soft tissue sarcoma that mainly occurs in the lower and upper extremities, trunk and retroperitoneum. However, primary MFH of the spleen is especially rare. Only 11 cases of splenic MFH have been reported in the English literature. In this report, we describe a 35-year-old man who was found to have a large accumulation of free fluid in the abdominal cavity and a tumor mass 6 cm in diameter with rupture within the spleen by the abdominal ultrasonography. A splenectomy was performed and the histological diagnosis was malignant fibrous histiocytoma. The patient died 7 months after the operation as a result of generalized metastasis. Compared with the 11 previously documented patients of splenic MFH, our patient is the youngest and the first case with spontaneous rupture, which makes our case exceedingly rare. A literature review of primary MFH of spleen is also provided.