Prognostic factors for patients with sarcomas of the pelvic bones.

BACKGROUND: Treatment of malignant tumors of the pelvis represents one of the most difficult problems in musculoskeletal oncology. However, factors that influence the local and systemic control of the disease remain ill-defined.
METHODS: One hundred and two patients with localized pelvic sarcomas who underwent a surgical excision of the tumors were analyzed. The tumor diagnosis was chondrosarcoma in 49 patients, osteosarcoma in 26 patients, Ewing's sarcoma in 20 patients, and other tumors in 7 patients. The tumor was located in the ilium in 65 patients, the pubis in 21 patients, the ischium in 8 patients, and the sacrum in 8 patients. Eighty-three patients underwent a limb-sparing surgery and 19 patients underwent hemipelvectomy. Prognostic factors for local recurrence, metastasis, and survival were analyzed.
RESULTS: At last follow-up, 47 patients were disease free, 7 were alive with disease, and 48 had died. The 5-year survival rate was 55% (chondrosarcoma: 65%, osteosarcoma: 47%, and Ewing's sarcoma: 52%). Inadequate surgical margin emerged as the only independent adverse prognostic factor for local recurrence. For distant metastasis, surgical stage remained as an independent prognostic factor. Patients who underwent a hemipelvectomy and those who had an inadequate surgical margin had significantly poorer survivals.
CONCLUSIONS: Pelvic sarcomas remain diseases with a poor prognosis. Independent prognostic factors are few; an adequate surgical margin is critical to prevent local recurrence, and the surgical stage is related to the risk of distant metastasis. Surgical margins and hemipelvectomy were predictors of survival, but the patients who underwent hemipelvectomy also tended to have the largest, most advanced tumors. Hemipelvectomy should be considered when there is sacral involvement.