Epithelioid sarcoma

Epithelioid sarcoma is another challenging and deadly tumor worthy of special consideration. Although this sarcoma is generally rare, the most common location is the distal upper and lower extremities, with approximately 15% of all cases located in the distal lower extremity. Most patients are young adults, with 75% percent of cases occurring in persons under 40, but children and the elderly may be affected. Men are affected more commonly than women.

The tumor may present as a small, firm superficial or deep nodule or a focal cluster of nodules. Regional multifocal presentation is an unusual characteristic displayed by this tumor. This tumor is frequently misdiagnosed as a skin condition, warts, or corns, and a correct diagnosis may be delayed with serious medical and legal consequences. About one half of the tumors are not painful.

The tumor grows and spreads along lymph and vascular channels as well as tendon sheaths, leading to more generalized swelling and a permeative mass. Contrast-enhanced MRI and PET CT imaging of the entire limb is essential to detect the complete extent of the disease and locate the frequent local and regional metastases.

For surgically controllable disease, surgical removal with a wide margin is mandatory. Local andregional metastasis may necessitate amputation. The local recurrence rate is approximately 35% and the rate of distant metastasis is about 40%, with the regional lymph nodes and lungs being the most common metastatic sites. Metastasis to regional lymph nodes occurs in 25% of cases. Five and ten year survival is 70% and 42%.

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