Postmetastasis survival in high-grade extremity osteosarcoma: A retrospective analysis of prognostic factors in 126 patients.

BACKGROUND AND OBJECTIVES: Prognostic factors predictive of postmetastasis survival (PMS) in metastatic osteosarcoma are poorly understood. Our aims were to evaluate PMS in patients with high-grade osteosarcoma in extremities, and to identify prognostic factors related to PMS.

METHODS: A retrospective review of data for 126 patients with metastatic osteosarcoma was conducted. The study population consisted of 70 men and 56 women, with a mean age of 21 years (range: 4-75 years). The mean postmetastasis follow-up period was 37 months (range: 1-245 months).

RESULTS: The 5-year PMS rate was 31% and median PMS duration was 22 months. In the multivariate analyses, no metastasectomy (P < 0.001), local recurrence prior to metastasis (P = 0.016), extrapulmonary metastasis (P = 0.006), and poor histologic response to preoperative chemotherapy (P = 0.047) were significant poor prognostic factors. The 5-year PMS without any negative prognostic factor was 60.2%; with one factor, 31.6%; and with more than two factors, 3.6%.

CONCLUSIONS: PMS in osteosarcoma patients was influenced by primary tumor-related factors such as histologic response to chemotherapy, as well as metastasis-related factors such as complete metastasectomy and metastasis site. A certain group of patients without such poor prognostic factors could be cured even after the development of metastasis.