CT features of calcifications in abdominal malignant fibrous histiocytoma

The purpose of this study was to describe the computed tomographic (CT) features of intralesional calcifications in abdominal malignant fibrous histiocytomas (MFH). Forty-three pathologically proven abdominal MFH with preoperative CT were retrospectively reviewed, of which seven tumors with intralesional calcifications were studied with pathohistologic correlation. All seven calcified abdominal MFH belonged to the storiform-pleomorphic subtype with peripherally located calcifications that appeared as either lumpy (three cases) or ringlike (four cases), which were due to the presence of variable amounts of osseous (six cases) and chondroid metaplasia (two cases). About 16% of abdominal MFH, especially the storiform-pleomorphic subtype, exhibited metaplastic calcifications which were characteristically located at the periphery of the tumor and appeared as either lumpy or ringlike on CT.