The fibroma-like variant of epithelioid sarcoma

Abstract

Five cases of a previously undescribed variant of epithelioid sarcoma are presented. This variant differs from the usual lesion in its absence of the typical necrobiotic nodular epithelioid pattern. It is instead composed of deceptively bland fibrohistiocytic and myoid cells arranged in a fibroma‐like or dermatofibroma‐like pattern with an affinity for osseous involvement. The clinical presentation, ultrastructural features, and presence of vimentin and low molecular weight keratin within the tumor cells justifies their designation as an epithelioid sarcoma variant. Cancer 1992; 69:1382‐1395.

Pleomorphic liposarcoma of a young woman following radiotherapy for epithelioid sarcoma

“…(1) dedifferentiation, (2) abrupt change to a higher grade sarcoma and (3) acquisition of differentiation 7 has not been reported in epithelioid sarcomas. This statement is also true for the fibroma-like variant of ES reported by Mirra et al 15 et al in 1992 in which bland spindle cell proliferation predominates in storiform or desmoid-like pattern. In the recurrent fibroma-like variant of ES Mirra et al 15 observed increasing anaplasia but not change in the histological appearance.…”

“…This statement is also true for the fibroma-like variant of ES reported by Mirra et al 15 et al in 1992 in which bland spindle cell proliferation predominates in storiform or desmoid-like pattern. In the recurrent fibroma-like variant of ES Mirra et al 15 observed increasing anaplasia but not change in the histological appearance. In the second tumor of our case the spindle cells were pleomorphic and negative for epithelial markers, consequently the diagnosis of recidive ES with fibroma-like features could be excluded.…”

An aggressive case of pseudomyogenic haemangioendothelioma of bone with pathological fracture and rapidly progressive pulmonary metastatic disease: case report and review of the literature

“…More than 2 decades ago, Mirra et al described five cases of a distinctive cytokeratin-positive soft tissue tumour characterised by multifocal involvement in a single limb [1]. Because the tumour commonly presents in the extremities of young patients, they suspected a variant of epithelioid sarcoma.…”

“…Comprehensive immunohistochemical (IHC) studies by these authors suggested that these tumours were endothelial in origin rather than epithelioid tumours. Despite their multicentric and ominous presentation, they have been shown to generally behave in an indolent clinical manner at follow-up [1][2][3].…”

“…Multifocal, multi-layered involvement confined to one anatomical area with non-contiguous limb involvement makes these tumours quite unusual. The bone lesions are most commonly cortically based although medullary involvement has been described [1,4,5]. Patients almost always present with soft tissue disease with, to the best of our knowledge, only three previous cases of purely osseous PMH described in the literature [3,4,6].…”