Surgical indications for Ewing's sarcoma of the pelvis

Despite advances in adjuvant therapy, Ewing's sarcoma of the pelvis remains an anatomic site with a poor prognosis. This study evaluate the role of surgery in the management of patients with pelvic Ewing's sarcoma who also received conventional radiation therapy and chemotherapy.

From May 1978 to February 1994, 19 patients with Stage IIB Ewing's sarcoma of the pelvis were treated at the UCLA Medical Center (Los Angeles, CA). There were eight lesions of the ilium, two of the sacrum, and nine involving two adjoining regions of pelvis. All patients received conventional medical management. The 19 patients were divided into two groups according to treatment modality. A group of 12 patients (Group A) had surgical resection, and their results were compared with those of another group of 7 patients (Group B) who did not have surgery.

The 5-year cumulative survival (Kaplan-Meier method) was 39% for all patients, 51% for Group A, and 18% for Group B. The 3-year cumulative survival was 59% for all patients, 72% for Group A, and 36% for Group B. Although the survival rate of Group A seemed better than that of Group B, the difference was not statistically significant (P = 0.093, log rank method). This study also suggested that, regardless of treatment modality, the outcome of patients with lesions involving two adjoining pelvic bones was poorer than that of those with a single lesion. In Group A, the 3-year cumulative survival rate for patients with single bone lesions (n = 8) was 86% and for patients with lesions involving two adjoining pelvic bones (n = 4) was 50% (P = 0.045, log rank method). Furthermore, the statistical analysis of the combined data of the single pelvic bone lesions in UCLA and that of Mayo Clinic series (n = 16 for surgery group and n = 15 for nonsurgery group) confirmed the better results for the surgical patients, which was consistent with the results from the Mayo Clinic with an even greater significance (P < 0.002).

This study demonstrates that surgery plus chemotherapy and radiation therapy is helpful for treating patients with pelvic Ewing's sarcoma so long as the tumor is limited to a single pelvic bone.