[Ewing's sarcoma of the pelvis: treatment results of 31 patients]

To define oncologic and functional outcomes of multidisciplinary treatment methods combined chemotherapy, surgery and radiotherapy, patients with Ewing's sarcoma of the pelvis who were treated at our center were analyzed.

Thirty-one patients with Ewing's sarcoma of the pelvis were eligible for this analysis. Primary lung metastases occurred in ten patients who were classified as stage III according to the system of Musculoskeletal Tumor Society (MSTS). All the patients received multidisciplinary treatment methods combined chemotherapy, surgery and radiotherapy. Twenty-eight patients underwent limb-sparing surgery, three patients underwent hemipelvectomy. The complications, including radiation or surgery-related complications and mechanical failures were recorded, besides the functional results were evaluated according to the MSTS 93 criteria. Kaplan-Meier survival analysis and Cox multivariate analysis were used as statistical methods.

The 5-year overall survival (OS) rate for all the patients was 42.3%. The 5-year OS for patients with small tumor (< 10 cm) had a significant better prognosis than patients with large tumor (≥ 10 cm, 58.2% vs. 26.0%, χ(2) = 4.382, P < 0.05). The 5-year OS for patients with surgical stage IIb was significantly better than for those with surgical stage III (50.2% vs. 30.3%, χ(2) = 4.521, P < 0.05). The 5-year OS for patients with wide or radical surgery had a better prognosis than patients with marginal, intralesional surgery or no surgery (60.0% vs. 29.4%, χ(2) = 4.851, P < 0.05). In multivariate analysis, surgical stage III (RR = 2.480, 95%CI: 0.857 - 7.173) and resection margin (RR = 2.576, 95%CI: 0.474 - 14.011) were independent prognostic factors. The mean MSTS 93 score for all the patients was 63.3%. The complication rate in patients treated with surgery was 29.0% (9/31).

Patients with Ewing'sarcoma of the pelvis can benefit from multidisciplinary treatment in terms of improved survival, acceptable functional results and reasonable complications. Surgical staging and resection margin are independent prognostic factors.