Abstract
BACKGROUND: Chemotherapy has improved the outcome of patients with newly diagnosed osteosarcoma, but its role in relapsed disease is unclear. METHODS: We reviewed the records of all patients who were treated for relapsed high-grade osteosarcoma at our institution between 1970 and 2004. Postrelapse event-free survival (PREFS) and postrelapse survival (PRS) were estimated, and outcome comparisons were made using an exact log-rank test. RESULTS: The 10-year PREFS and PRS of the 110 patients were 11.8% ± 3.5% and 17.0% ± 4.3%, respectively. Metastasis at initial diagnosis (14%), and relapse in lung only (75%) were not significantly associated with PREFS or PRS. Time from initial diagnosis to first relapse (RL1) ≥18 months (43%), surgery at RL1 (76%), and ability to achieve second complete remission (CR2, 56%) were favorably associated with PREFS and PRS (P ≤ 0.0002). In patients without CR2, chemotherapy at RL1 was favorably associated with PREFS (P = 0.01) but not with PRS. In patients with lung relapse only, unilateral relapse and number of nodules ( ≤ 3) were associated with better PREFS and PRS (P ≤ 0.0005); no patients with bilateral relapse survived 10 years. The median PREFS after treatment with cisplatin, doxorubicin, methotrexate, and ifosfamide was 3.5 months (95% confidence interval, 2.1-5.2), and the median PRS was 8.2 months (95% confidence interval, 5.2-15.1). CONCLUSIONS: Late relapse, surgical resection, and unilateral involvement (in lung relapse only) favorably impact outcome after relapse. Surgery is essential for survival; chemotherapy may slow disease progression in patients without CR2. These data are useful for designing clinical trials that evaluate novel agents.