Synovial sarcoma appears to be more sensitive to chemotherapy than many other STSs, and children with synovial sarcoma seem to have a better prognosis when compared with adults.[5,127,131,132,133,134,135,136,137] The most commonly used regimens for the treatment of synovial sarcoma incorporate ifosfamide and doxorubicin.[135,138,139] Response rates to the ifosfamide and doxorubicin regimen are higher than in other nonrhabdomyosarcomatous STSs. A meta-analysis also suggested that response to chemotherapy was correlated with improved survival.
Several treatment centers advocate adjuvant chemotherapy following resection and radiation therapy of synovial sarcoma in children and young adults.[128,136,139,141,142,143] The International Society of Pediatric Oncology-Malignant Mesenchymal Tumors studies showed that select patients (young age, < 5 cm resected tumors) with nonmetastatic synovial sarcoma can have excellent outcome in the absence of radiation, but it is still unclear whether or not that approach obviates an advantage of radiation for local or regional control. A German trial suggested a benefit for adjuvant chemotherapy in children with synovial sarcoma. A meta-analysis also suggested that chemotherapy may provide benefit. However, unequivocal proof of the value of adjuvant chemotherapy from prospective, randomized clinical trials is lacking and the results of COG-ARST0332 are pending. Survival following relapse is poor (30% at 5 years). Factors associated with outcome after relapse include duration of first remission (> or ≤ 18 months) and lack of a second remission.
Undifferentiated sarcoma; sarcoma, NOS
Patients with undifferentiated STS had been eligible for participation in rhabdomyosarcoma trials coordinated by the Intergroup Rhabdomyosarcoma Study Group and the Children's Oncology Group (COG) from 1972 to 2006. The rationale was the observation that patients with undifferentiated STS had similar sites of disease and outcome as those with alveolar rhabdomyosarcoma. Therapeutic trials for adults with STS include patients with undifferentiated STS and other histologies, which are treated similarly, using ifosfamide and doxorubicin, and sometimes with other chemotherapy agents, surgery, and radiation therapy. Currently in the COG, they are treated on clinical trials for patients with nonrhabdomyosarcomatous STSs.
Vascular tumors vary from hemangiomas, which are always considered benign, to angiosarcomas, which are highly malignant. Vascular tumors include the following tumor subtypes:
- Angiosarcoma (deep).
- Epithelioid hemangioendothelioma.
- Hemangiopericytoma (infantile).
Complete surgical excision appears to be crucial for angiosarcomas and lymphangiosarcomas despite evidence of tumor shrinkage in some patients in response to local or systemic therapy.[146,147,148,149] A review of 222 patients (median age, 62 years; range, age 15–90 years) showed an overall disease-specific survival (DSS) rate of 38% at 5 years. Five-year DSS was 44% in 138 patients with localized, resected tumors but only 16% in 43 patients with metastases at diagnosis.