Ewing Tumor of Bone/Specific Sites
Separate journal articles have been written that discuss diagnostic findings, treatment, and outcome of patients with bone lesions at the following sites:
- Hand and foot.[37,38]
- Chest wall/rib.[39,40,41,42]
- Head and neck.
Extraosseous Ewing Sarcoma
Extraosseous Ewing sarcoma (EOE) is biologically similar to Ewing sarcoma arising in bone. Until recently, most children and young adults with EOE were treated on protocols designed for the treatment of rhabdomyosarcoma. This is important because many of the treatment regimens for rhabdomyosarcoma do not include an anthracycline, which is a critical component of current treatment regimens for Ewing tumor of bone (ETB). Currently, patients with EOE are eligible for studies that include ETB.
From 1987 to 2004, 111 patients with nonmetastatic EOE were enrolled on the RMS-88 and RMS-96 protocols. Patients with initial complete tumor resection received ifosfamide, vincristine, and actinomycin (IVA) while patients with residual tumor received IVA plus doxorubicin (VAIA) or IVA plus carboplatin, epirubicin, and etoposide (CEVAIE). Seventy-six percent of patients received radiation. The 5-year EFS and OS were 59% and 69%, respectively. In a multivariate analysis, independent adverse prognostic factors included axial primary, tumor size greater than 10 cm, IRS Group III, and lack of radiation therapy.
Two hundred thirty-six patients with EOE were entered on studies of the German Pediatric Oncology Group. The median age at diagnosis was 15 years and 133 patients were male. Primary tumor site was either extremity (n = 62) or central site (n = 174). Sixty of 236 patients had metastases at diagnosis. Chemotherapy consisted of vincristine, doxorubicin, cyclophosphamide, and actinomycin (VACA); CEVAIE or; vincristine, ifosfamide, doxorubicin, and etoposide (VIDE). The 5-year EFS and OS were 49% and 60%, respectively. Five-year survival was 70% for patients with localized disease and 33% for patients with metastases at diagnosis. OS in patients with localized disease did not seem related to tumor site or size. In a retrospective French study, patients with EOE were treated using a rhabdomyosarcoma regimen (no anthracyclines) or an ETB regimen (includes anthracyclines). Patients receiving the anthracycline-containing regimen had a significantly better EFS and OS compared with patients receiving no anthracyclines.[50,51]
Superficial Ewing sarcoma is a soft tissue tumor in the skin or subcutaneous tissue. Two small series suggested that superficial Ewing sarcoma had a better prognosis than tumors arising in other sites, but not all cases had molecular confirmation of diagnosis.[53,54] A larger series of molecularly confirmed cases reported that patients with superficial Ewing sarcoma did well when treated with local control and systemic therapy similar to the therapy used for all other Ewing sarcoma patients.