Sclerosing epithelioid fibrosarcomas involving the neuraxis: report of three cases.

ABSTRACT

OBJECTIVE AND IMPORTANCE Sclerosing epithelioid fibrosarcoma (SEF) is a rare mesenchymal neoplasm composed of rounded, vimentin-immunoreactive tumor cells disposed in nests and cords within a hyalinized collagenous matrix. Most examples arise in the deep skeletal muscles of adults. The cases recorded to date have been characterized by protracted clinical evolutions with a tendency for stubborn local recurrence, followed by late metastasis. Accordingly, SEF has been regarded as a low-grade sarcoma. A single instance of brain and vertebral metastasis has been described. We report three examples of SEF distinguished by primary involvement of the neuraxis at initial presentation. CLINICAL PRESENTATION Two tumors had intracranial, calvarial and extracalvarial, soft-tissue components, whereas the third tumor manifested as a paraspinal mass with extension into the T12-L1 neural foramen and invasion of the T12 nerve root. INTERVENTION All three affected patients experienced local recurrence and distant metastasis after resection of the primary site. These complications appeared early in the disease course in two cases. In no case was there a response to adjuvant chemotherapy or radiotherapy. CONCLUSION: Our experience indicates that SEFs arising along the neuraxis may demonstrate unexpectedly aggressive clinical behavior, compared with those arising in the more typical location of deep skeletal muscles.