Sclerosing epithelioid fibrosarcoma of the thigh: report of two cases with synchronous bone metastases

Sclerosing epithelioid fibrosarcoma of the foot: A case report

Sclerosing epithelioid fibrosarcoma (SEF) is a rare and distinctive variant of fibrosarcoma. To date, about 100 cases only have been documented. Histopathologically, it resembles a variety of benign, pseudosarcomatous and other malignancies. Early diagnosis and treatment are vital for improving the treatment outcomes.

Metastatic Pediatric Sclerosing Epithelioid Fibrosarcoma

Sclerosing epithelioid fibrosarcoma (SEF) is a rare and aggressive soft-tissue sarcoma thought to originate in fibroblasts of the tissues comprising tendons, ligaments, and muscles. Minimally responsive to conventional cytotoxic chemotherapies, >50% of SEF patients experience local recurrence and/or metastatic disease. SEF is most commonly discovered in middle-aged and elderly adults, but also rarely in children. A common gene fusion occurring between the EWSR1 and CREB3L1 genes has been observed in 80%–90% of SEF cases. We describe here the youngest SEF patient reported to date (a 3-yr-old Caucasian male) who presented with numerous bony and lung metastases. Additionally, we perform a comprehensive literature review of all SEF-related articles published since the disease was first characterized. Finally, we describe the generation of an SEF primary cell line, the first such culture to be reported. The patient described here experienced persistent disease progression despite aggressive treatment including multiple resections, radiotherapy, and numerous chemotherapies and targeted therapeutics. Untreated and locally recurrent tumor and metastatic tissue were sequenced by whole-genome, whole-exome, and deep-transcriptome next-generation sequencing with comparison to a patient-matched normal blood sample. Consistent across all sequencing analyses was the disease-defining EWSR1–CREB3L1 fusion as a single feature consensus. We provide an analysis of our genomic findings and discuss potential therapeutic strategies for SEF.

Giant Sclerosing Epithelioid Fibrosarcoma of the Thigh: A Case Report

CASE

We present a case of a 35-year-old-man with a giant sclerosing epithelioid fibrosarcoma (SEF) of the thigh. The patient presented with a history of a painful thigh mass. Plain radiographs revealed a soft-tissue mass with extensive calcifications, whereas on magnetic resonance imaging, a lobulated mass between the adductors and the posterior muscles of the thigh was noted. A wide en block resection was undertaken, and the histopathology confirmed the diagnosis of SEF. Postoperative radiation therapy was followed. The patient had no signs of recurrence at the 4-year follow-up.

CONCLUSION

The clinicopathological, imaging characteristics, and treatment options of this rare soft-tissue tumor are discussed.

Primary sclerosing epithelioid fibrosarcoma of the spine: a single-institution experience

AIMS

To present our experience on spinal sclerosing epithelioid fibrosarcoma (SEF) and review the existing literature pertaining to SEF of the spine.

METHODS AND RESULTS

Six cases of spinal SEF were reviewed, and a literature search of all primary SEFs of the spine was performed. All tumours occurred in adults (median age, 41 years) and were located all along the spine, the lumbar vertebrae being the most commonly involved. All patients presented with pain that they had experienced for months. The mean tumour size at diagnosis was 52 mm. Five tumours showed a spectrum of microscopic features consistent with pure SEF, and one showed a hybrid morphology with areas of low-grade fibromyxoid sarcoma. All were diffusely and strongly positive for mucin 4. Two cases were initially misdiagnosed as epithelioid haemangioendothelioma and aggressive chondroblastoma. Fluorescence in-situ hybridisation showed rearrangements of either FUS or EWSR1 in four cases. Reverse transcription polymerase chain reaction showed the presence of FUS-CREB3L1 and EWSR1-CREB3L1 fusion transcripts in two cases and one case, respectively. Of five patients with follow-up data available, two developed one or more local recurrences and three patients had metastatic disease. Distant metastases were mainly to other osseous locations, followed by lungs and lymph nodes. At last follow-up, three patients had died of disease and one was alive with multiple metastases.

CONCLUSIONS

SEF is an aggressive sarcoma that can involve the spine. It is important to recognise the spine as the primary location of SEF, in order to avoid misdiagnosis as more common primary spinal neoplasms, which can impact on therapeutic approaches.

Case Report: Radiological Features of Sclerosing Epithelioid Fibrosarcoma in the Right Fibula

Background

Sclerosing epithelioid fibrosarcoma (SEF) is an extremely rare, aggressive malignant subtype of fibrosarcoma. Only dozens of cases of primary SEF in the bone have been reported so far, without case involving fibula reported in literature to date. Herein we report the first case of primary SEF in the right fibula in a 19-year-old man. In this case report, we firstly give a comprehensive description of fibula SEF, including its complete clinical course and radiological findings.

Case Presentation

A 19-year-old man presented with a half-year history of soreness in the right lower leg. Contrast-enhanced computed tomography (CE-CT) and magnetic resonance imaging (MRI) of the right lower leg were performed. Based on the radiological examinations, a diagnosis of malignant tumor arising in the fibular diaphysis was made. Final diagnosis of primary SEF in the right fibula was confirmed by histopathological and immunohistochemical examinations after surgical resection. The patient had no signs of recurrence or metastasis during a 24-month follow-up.

Conclusion

We report an exceedingly rare case of primary SEF in the right fibula and its radiological features with CE-CT and MRI.

Sclerosing epithelioid fibrosarcoma of bone: morphological, immunophenotypical, and molecular findings of 9 cases

Primary sclerosing epithelioid fibrosarcoma (SEF) of bone is a rare and scarcely reported neoplasm. We document clinicopathological and molecular features of 9 additional cases. Five males and 4 females had a mean age of 39 years (14-71 years). Most tumors affected flat/irregular bones; only 3 cases involved a long bone. By radiology, it has characteristic radiographic features of a predominantly lytic expansile lesion with a sclerotic rim. Referring diagnoses were SEF (n = 2), low-grade osteosarcoma (n = 2), chondrosarcoma (n = 1), and chondromyxoid fibroma (n = 1). Histologically, five cases revealed classical morphology of SEF of soft tissue. Remaining cases were classified as hybrid SEF/low-grade fibromyxoid sarcoma, characterized by spindle or stellate cells, prominent stroma, and giant hyalinized areas. Various morphological deviations such as prominent vasculature (n = 3), osteoid-like material (n = 4), or parallel bone trabeculae (n = 2) were observed. Immunohistochemically, all cases showed diffuse and strong MUC4 expression. SATB2 was observed in 5/8 cases. Using FISH, EWSR1, and FUS rearrangements were detected in 4 cases and 1 case, respectively. EWSR1-CREB3L1 fusion was identified in 1 additional case by next-generation sequencing. Recurrence and metastasis were observed in 1 case and 2 cases, respectively. All but one patient were alive with disease for a mean interval of 31 months. SEF of bone is a relatively indolent sarcoma of adults, most commonly located in the flat/irregular bones. Due to overlapping histological features, it is often misdiagnosed as osteosarcoma or a chondroid tumor. Most SEF of bone exhibit EWSR1 rearrangements, but rare cases may harbor a FUS gene fusion.

Composite peek/carbon fiber pre-shaped rods and sublaminar bands for posterior stabilization of cervico-thoracic junction: A novel technique

The combination of surgery plus radiotherapy is a valid treatment option when en bloc resection with wide margins is not feasible. The aim of this paper is to show a novel technique for fixation of cervico-thoracic junction with carbon fiber reinforced peek pre-shaped rods with sublaminar bands in order to guarantee cervical spine stability and particle therapy efficacy. A 42 years-old man with a Sclerosing Epithelioid Fibrosarcoma (SEF) arising from C7, involving the right latero-cervical region from C5 to the apex of the right lung, underwent an en bloc resection with a double approach (anterior plus posterior). Fixation of cervical spine was achieved with composite PEEK/carbon fiber rods connected to C4 and T2 laminae with sublaminar bands. After surgery, the patient received 9 cycles of chemotherapy (cisplatin, etoposide and adriamycin) and proton therapy. At 2 years follow-up, no local recurrence was detected with implant stability demonstrating no mechanical failure. The main issues related to this case were: planning en bloc resection able to achieve an Enneking appropriate margin; incorporate in the decision making process the functional loss related to the sacrifice of neurological structures infiltrated by the tumor; establish a therapeutic strategy that included, in addition to surgery, adjuvant chemotherapy and radiotherapy for improving local and systemic control; stabilize with implants that do not interfere with accelerated particle radiotherapy.

Metastatic Sclerosing Epithelioid Fibrosarcoma in Bone Marrow

Sclerosing epithelioid fibrosarcoma (SEF) is an aggressive neoplasm thought to be related to low-grade fibromyxoid sarcoma, which typically occurs in middle-aged adults in the deep soft tissues of the lower extremities and trunk. It comprises nests and cords of relatively uniform epithelioid polygonal cells with clear or eosinophilic cytoplasm in densely sclerotic stroma, and it is typically associated with EWSR1 gene rearrangements, and most commonly EWSR1-CREB3L1 fusions. As primary SEF can arise in bone, and bone is also a common metastatic site for SEF, its recognition at this site is important. We illustrate bone marrow showing diffuse infiltration by SEF and highlight the potential for confusion with a range of neoplasms such as carcinoma, hematolymphoid neoplasms, and other sarcomas.