Sclerosing epithelioid fibrosarcoma

Sclerosing epithelioid fibrosarcoma
Synonyms	SEF
Pronounce	N/A
Specialty	N/A
Symptoms	Pain, swelling, mass
Complications	Metastasis
Onset	Typically in adulthood
Duration	Chronic
Types
Causes	Unknown
Risks
Diagnosis	Biopsy, imaging studies
Differential diagnosis	Fibrosarcoma, low-grade fibromyxoid sarcoma
Prevention
Treatment	Surgery, radiation therapy, chemotherapy
Medication
Prognosis	Variable, depends on stage and treatment
Frequency	Rare
Deaths	N/A

Sclerosing Epithelioid Fibrosarcoma Sclerosing epithelioid fibrosarcoma (SEF) is a rare type of soft tissue sarcoma that is characterized by its unique histological appearance and aggressive clinical behavior. It is considered a variant of fibrosarcoma, distinguished by its sclerosing and epithelioid features.

Clinical Presentation

Patients with sclerosing epithelioid fibrosarcoma typically present with a slow-growing mass. The tumor can occur in various locations, including the extremities, trunk, and head and neck region. It is most commonly diagnosed in adults, but cases have been reported across a wide age range.

Histopathology

Histologically, SEF is characterized by nests and cords of small, round to oval epithelioid cells embedded in a densely sclerotic stroma. The tumor cells often exhibit mild nuclear atypia and scant cytoplasm. Mitotic activity is generally low, but the presence of necrosis and increased mitotic figures can be observed in more aggressive cases.

Immunohistochemistry

Immunohistochemical staining is crucial for the diagnosis of SEF. The tumor cells typically express vimentin and may show focal positivity for epithelial markers such as cytokeratin and epithelial membrane antigen (EMA). Other markers, such as CD34 and S-100, are usually negative, helping to differentiate SEF from other soft tissue tumors.

Genetic Features

Molecular studies have identified recurrent genetic alterations in SEF, including EWSR1-CREB3L1 and EWSR1-CREB3L2 gene fusions. These genetic markers can aid in the diagnosis and differentiation from other sarcomas.

Prognosis and Treatment

The prognosis for patients with sclerosing epithelioid fibrosarcoma is generally poor due to its high potential for local recurrence and distant metastasis, particularly to the lungs. Treatment typically involves wide surgical excision with negative margins. The role of radiation therapy and chemotherapy is not well established but may be considered in cases of unresectable or metastatic disease.

Differential Diagnosis

The differential diagnosis for SEF includes other soft tissue tumors such as:

• Synovial sarcoma
• Epithelioid sarcoma
• Desmoplastic small round cell tumor

Also see

• Soft tissue sarcoma
• Fibrosarcoma
• Epithelioid sarcoma
• Histopathology