Background: In 326 patients with Ewing's sarcoma family tumor (ESFT) and 628 extremity osteosarcoma (OS) treated with adjuvant and neo-adjuvant chemotherapy and event-free survivors 5 years from the beginning of treatment we evaluated outcome in the following years. Post 5-year follow-up for these patients was 9.7 years (5.5-29 years).
Patients and methods: Adverse events observed after 5-year follow-up were 73 (7.6%): 38 late relapses, nine leukemia, 14 second solid tumor, seven radioinduced sarcoma, three severe adriamycin-related cardiomyopathy, one suicide and one death by car crash.
Results: Of the patients who developed late events, 16 (22.5%) are alive and event free after 8 years from the last treatment (2-22 years).
Conclusion: We conclude that the high rate of late adverse events after 5 years in patients with OS and ESFT is noteworthy and indicates that these patients should be followed for >5 years.