Primary sclerosing epithelioid fibrosarcoma of the sacrum: a case report and review of the literature

Abstract

Sclerosing epithelioid fibrosarcoma is a rare tumour characterised histologically by a predominant population of epithelioid cells arranged in strands and nests, embedded in a fibrotic and hyalinised stroma. It is a low grade tumour with an indolent course. A 48 year old woman presented with a painful swelling over her back for six months. Investigation and biopsy revealed features of sclerosing epithelioid fibrosarcoma involving the left half of the sacrum, left sacro-iliac joint, and posterior part of the left ilium. Preoperative radiotherapy and wide location excision of the tumour were followed by metastatic recurrence of the tumour in the lung and scalp six years after initial presentation. The tumour showed typical histology of sclerosing epithelioid fibrosarcoma. The radiological features confirmed its primary location in the sacrum. The patient declined chemotherapy and died of disseminated disease eight years after initial presentation. Review of the literature confirms the fact that sclerosing epithelioid fibrosarcoma, despite its low grade, is a clinicopathologically distinct tumour with full malignant potential, the recurrence, metastasis, and mortality rate being 48%, 60%, and 35%, respectively. Sclerosing epithelioid fibrosarcoma can occur as a primary bone tumour, the clinical behaviour of which is probably similar to its soft tissue counterpart.

Sclerosing Epithelioid Fibrosarcoma – A Rare Sacral Lesion and Literature Review

“…There are several descriptions of metastatic lesions at the time of presentation [23]. One important concern was the reference to a much higher proliferative activity on metastatic tumour cells (60%), when comparing the staining positivitymortality evaluation, with rates from 35% to 60% [5,7,10]. On the comprehensive report of Ossendorf et al [6], that included 90 patients, twenty-three patients (34%) died from their disease after a mean of 46 months.…”

“…Those features were not specific. The typical image of SEF with bone involvement is predominantly lytic and poorly marginated [5,10]. Accordingly, the following mainly tumours were included in the differential diagnosis: osteosarcoma, liposarcoma, assorted mesenchymal neoplasms that may exhibit epithelioid appearances, metastatic carcinoma, sclerosing hematolymphoid tumours, and malignant melanoma.…”

“…Metastatic rate reports range from 40% to 86% and the interval ranged from synchronous with the primary diagnosis to 14 years [6,7,23]. The median interval to the first local recurrence was 4.8 years (range, 2.3-11 years) and that to metastasis was 7.7 years (range, 4.7-14 years) [2,10,22]. There are several descriptions of metastatic lesions at the time of presentation [23].…”

“…Sarcomas are rare malignant tumours of mesenchymal origin, accounting for less than 1% of all new cancer diagnoses [10] SEF represents a small subtype of soft tissue sarcomas, that is often linked to low-grade fibromyxoid sarcoma (LGFMS) and hyalinizing spindle cell tumour with giant rosettes (HSCTGR) [8,11,12].…”

“…The first description of SEF with bone origin was found in 2002 by Abdulkader et al [4] that reported a case of an iliac SEF as a primary bone tumour. To our knowledge, on literature (Embase®, NCBI-Pubmed® and Google Scholar®), from around 20 cases of SEF arising from bone [7][8][9], five cases were allocated to the axial skeleton, but there is only one report of sacrum involvement, by Chow et al [10]. Here we describe a rare case of SEF arising from sacral bone tissue, an unusual origin and location for such a relatively rare lesion.…”