epithelioid sarcoma

Epidemiology

• most 2nd to 4th decades
• male predominance

Microscopic pathology

• nodules & clusters of eosinophilic epithelioid or spindled cells
• complex nuclear outlines
• little pleomorphism
• variants:
  • large cell or proximal variant: worse prognosis
  • angiomatoid variant: contain hemorrhagic cysts lined by epitheliod sarcoma cells
• fibrohistiocytic variant: prominant spindle cells, infiltrated by epithelioid cells

Clinical manifestations

• fingers, hands, forearm and foot most common
• can occur in trunk, vulva, perineum and inguinal region
• often involves tendons, may ulcerate
• regional lymph node metastases
• distant metastases in 20-30%
  • typical sites: lung, soft tissue of scalp

Laboratory

Immunocytochemistry:

• vimentin: +
• CK8, CK18, CK19: majority of cells +
• CK7: focally + in 20% cases
• CK14: focally +
• CK17: rarely +
• CK20: -
• EMA: +
• CD34: ~50% +, membrane staining
• E-cadherin: -
• V-cadherin: +
• S100: rarely +
• desmin: rarely +

More general terms

• sarcoma

Patient information

epithelioid sarcoma patient information