MR Characteristics of Epithelioid Sarcoma

Abstract
The purpose of this study was to characterize MRI findings of epithelioid sarcomas and correlate them with the presence or absence of metastasis and/or recurrence. Thirty-six MRI studies were analyzed retrospectively in 12 patients with histologically proven epithelioid sarcomas. The following parameters were evaluated: lesion location, signal characteristics, and bone or vascular involvement. Also, the time of the appearance and the frequency of local recurrences were determined, as well as location, frequency, and timing of appearance of metastatic disease. Epithelioid sarcomas were located mainly in the upper extremities (58%). The MRI findings divided the tumor into two major categories: hemorrhagic (two patients) and nonhemorrhagic (ten patients). The study showed recurrence in 33% of the cases and metastasis in 50% overall. Both patients with hemorrhagic epithelioid sarcoma showed metastases that appeared earlier than metastases from nonhemorrhagic sarcomas. Only 33% of the nonhemorrhagic sarcomas showed metastases; and 17% of the cases revealed vascular invasion. Magnetic resonance plays a role in recognizing intratumoral hemorrhage in patients with epithelial sarcoma. Patients with hemorrhagic tumors need more aggressive treatments and follow-up studies.