Ewing's sarcoma family of tumors in Finland during 1990-2009: a population-based study.

BACKGROUND: Ewing's sarcoma family of tumors (ESFTs) are rare bone and soft tissue tumors characterized by specific genetic alterations. Our aim was to carry out a nationwide analysis of ESFT, to survey the treatments used and to report the five-year disease specific and event-free survival rates (EFS and DSS). MATERIAL AND METHODS: The study data was gathered from the Finnish National Cancer Registry and all five University Hospitals and consisted of 76 bone and soft tissue ESFT patients diagnosed during 1990-2009. Their medical records were reviewed and data on their disease, treatments, complications and outcome were analyzed. RESULTS: The five-year EFS and DSS of patients with localized disease at diagnosis (n = 57) were 70% and 60%, respectively. Factors contributing to DSS and EFS were the axial vs. peripheral site of primary tumor and adequate surgical resection of the primary tumor. DSS was also affected by patient's age at diagnosis and the treatment employed. The five-year DSS of patients with metastatic disease at diagnosis (n = 19) was 33% and both preoperative and high dose chemotherapy were associated with improved survival. CONCLUSION: Population-based studies including both bone and soft tissue ESFTs are few. In this nationwide, population-based study on Finnish bone and soft tissue ESFT patients, we find their treatment successful and results comparable to those previously published. Absence of metastases, young age at diagnosis and a peripheral primary tumor site were associated with a better prognosis. It seems that surgical resection of the primary tumor should be performed whenever adequate resection margins can be achieved. The role of high dose chemotherapy merits further studies in this setting.

Viable versus nonviable positive margins in Ewing sarcoma and associated recurrence rates: A systematic review.

Residual tumor after curative intent therapy in patients with Ewing's sarcoma is of great clinical significance. Surgeons use the resection margin to indicate the completeness of a surgical excision. However, this margin may be either nonviable/necrotic or viable. This systematic review examines the 5-year event-free survival rate and local recurrence as a function of positive resection margins that are nonviable/necrotic versus those that are viable. Multiple databases were searched using the Ovid interface. After full text screening, 45 articles that reported either margin or postchemotherapy histology and one or more outcomes of interest were identified, and two articles reported on margin and histology simultaneously. An attempt was made to contact the remaining authors and one author was able to provide additional data. The data from the three studies suggest that prognosis in ES depends on both margin involvement and the postchemotherapy histological response simultaneously. However, radiation therapy likely improves local control in patients with inadequate surgical margins, regardless of histological response. This is an area where there is a paucity of evidence that needs to be rectified to ensure that ES patients are provided the highest quality of evidence-based care.