Soft tissue clear cell sarcoma

  Clear cell sarcoma of soft tissue is a malignant tumor commonly found in the deep soft tissues of the limbs, usually around tendons and tendon sheaths. More than 90% of patients have translocations of chromosomes 12 and 22 in their tumors. The prognosis of patients is not related to the presence or absence of translocations or the type of translocation.  The majority of patients have lesions involving the extremities, with approximately 40% of patients presenting in the hands and feet, and the tumors are usually deep in location, rarely involving the skin or subcutis. Patients with gastrointestinal lesions usually involve the small intestine. The tumor is usually slow growing and half of the patients may have pain and tenderness. Metastases to the lymph nodes are more common in about half of the patients.  The disease does not respond well to chemotherapy and surgical resection is the mainstay, with radiation therapy available for patients with positive borders. Patients with progressive disease may be treated with sorefenib or sunitinib. some studies have shown effectiveness with vemurafenib for BRAF-mutated clear cell sarcoma. Chemotherapy regimens may be based on adriamycin, platinum and isocyclophosphamide. Intra-local lesion injections of interferon alpha have also been reported to be effective in the literature.  The overall prognosis of the disease is similar to that of patients with adenoid soft tissue sarcoma, with survival rates of about 67%, 33%, and 10% at 5, 10, and 20 years.