PELVIC LOCALISATIONS OF EWING SARCOMA AND OSTEOSARCOMA: 31 CASES

Abstract

Purpose: The purpose of this work was to analyse and compare survival in patients with osteosarcoma (OS) or Ewing sarcoma (EW) of the pelvis as a function of treatment.

Material and methods: This retrospective series included 31 patients with OS (n=15) or EW (n=16) of the pelvis who were given a homogeneous therapeutic sequence associating chemotherapy, surgery and/or radiotherapy. Mean follow-up was 37 months (2–144). Mean age was 20 years for EW and 28 years for OS. Localisations in the pelvis were: zone I (n=12), zone I and II (n=4), zone II (n=1), zone II and III (n=7), zone III (n=1), and zone I, II and III (n=6). All patients were given chemotherapy, 15 underwent surgery, and 16 were given radiotherapy alone. Five patients were given complementary radiotherapy after surgery. Actuarial survival curves were compared with the logrank test. Comparison factors were presence of surgical resection, presence of initial or secondary metastasis, tumour response (radiographic measure), and pathology (good or poor responder) after chemotherapy.

Results: Five-year survival rate for patients with EW was 53%, 31% for OS. There was no significant difference in survival rates between tumour type. The only factor significantly correlated with lower survival rate was presence of initial metastasis.

Discussion and conclusion : The pelvic localisation of osteosarcoma and Ewing sarcoma is a factor of poor prognosis. Unlike data reported in the literature, surgery did not appear to influence outcome, not being found to be a factor of better prognosis. Surgery does however appear to improve short-term survival. In the pelvic localisation, osteosarcoma appears to have a poorer prognosis in terms of survival than Ewing tumour.