Radiology and pathology of malignant fibrous histiocytomas of the soft tissues: a report of ten cases

Pleomorphic spindle cell sarcoma (PSCS) formerly known as malignant fibrous histiocytoma (MFH): a complex malignant soft-tissue tumor

A presentation defining the nature, characteristics, causation, treatment and outcome of patients with lesions formerly known as malignant fibrous histiocytoma and now as pleomorphic spindle cell sarcoma is clearly a very difficult subject. Many authors do not believe that the tumor exists and instead describe them as forms of fibrosarcomas, fibromyxoid lesions, dedifferentiated chondrosarcomas or even leiomyosarcomas. The reasons for this confusion are presumably related to the fact that the malignant pleomorphic spindle cell sarcoma does not seem to be a distinct type of lesion with specific histologic and genetic characteristics. Instead, the tumor has at least four separate histologic variations and no specific gene signature and in fact does not seem to be either familial or ethnic in presentation. In view of the fact that the tumor was traditionally the most frequently encountered malignant soft-tissue neoplasm, the world of orthopedic oncology is clearly distressed by the problems that these patients have and is joined by the radiation oncologists and chemotherapists in seeking new solutions.

Primary malignant fibrous histiocytoma of the chest wall: CT and MR appearance

PURPOSE

The purpose of this work is to describe the CT and MR appearance of primary malignant fibrous histiocytoma (MFH) of the chest wall.

METHOD

Eleven men and eight women (45-76 years old) with primary MFH of the chest wall who underwent both CT and MRI were enrolled, and the imaging interpretation was retrospectively compared to the pathologic specimen.

RESULTS

All tumors were inhomogeneous in appearance on CT scans. All tumors showed high signal intensity on T2-weighted images. On T1-weighted MR images, tumors displayed inhomogeneous isosignal intensity in 15 cases (79%) and low signal intensity in 5 (21%) compared with the surrounding muscle. Tumors exhibited inhomogeneous enhancement in all except three localized tumors on enhanced CT and MRI. Invasion of intercostal muscle was noted on MR images in 18 patients (95%) and on CT in 11 patients (58%).

CONCLUSION

There might be various radiologic appearances of MFH. However, CT and MRI are able to demonstrate the exact localization and disease extent of MFH arising in the chest wall.

Malignant fibrous histiocytoma of soft tissue imaging with emphasis on MRI

Malignant fibrous histiocytoma (MFH) is the most common soft tissue sarcoma in adults. This pictorial essay describes and illustrates the clinical, pathologic, and radiologic features of MFH. The cross-sectional imaging features on CT and MRI are emphasized in relation to the diagnosis and staging of MFH.

Magnetic resonance imaging of malignant fibrous histiocytoma

The magnetic resonance imaging (MRI) changes in 39 patients with malignant fibrous histiocytoma (MFH) were reviewed retrospectively. Twenty-one sarcomas were in the lower extremity, five each in the upper extremity and trunk, two each in the neck and heart, and one each in the maxillary sinus, sella turcica, tongue, and spermatic cord. The examinations were performed with spin-echo sequences on a 1.5 Tesla Signa Scanner (GE, Milwaukee WI). Twenty-two tumors exhibited intermediate signal intensity on T1-weighted images and 23 were of high signal intensity on T2-weighted images. There was no significant differences in signal intensity of 12 preoperative and 13 recurrent neoplasms. Twelve of 13 patients were correctly diagnosed as having postoperative changes. The MR sensitivity and specificity for detecting a neoplasm were 96% and 83% respectively, but the signal changes were nonspecific for MFH. When compared to CT in 14 patients, MR better defined the extent of the MFH, its relationship to surrounding tissues and vessels, and best differentiated residual or recurrent disease from postoperative changes when examined at least 3 months after surgery.

Angiography of histopathologic variants of synovial sarcoma

Synovial sarcomas are rare soft tissue tumors which histopathologically can be divided into monophasic, biphasic and mixed variants. As part of a protocol for intra-arterial chemotherapy 12 patients with biopsy proven synovial sarcoma underwent angiography. The angiograms on these patients were reviewed to determine whether synovial sarcomas and their variants demonstrated a characteristic angiographic appearance. Synovial sarcomas appeared angiographically as soft tissue masses which showed a fine network of tumor vessels with an inhomogeneous capillary blush. Their degree of vascularity varied according to their histopathology. Monophasic synovial sarcomas demonstrated in general a higher degree of neovascularity than the biphasic form. This finding was also suggested by histopathologic analysis of the vessels in the tumor. Although angiography did not show a distinctive vascular pattern it may be useful to evaluate tumor size and vascularity.