Outcome of postradiation osteosarcoma does not correlate with chemotherapy response

Postradiation osteosarcoma is a rare tumor with a historically poor prognosis. Recent reports concerning the prognosis of the disease have been conflicting. We ascertained the long-term outcome of patients with this disease treated in the era of contemporary chemotherapy. Twenty-seven patients diagnosed with postradiation osteosarcoma and treated with chemotherapy and surgical resection from 1980-2003 were identified. Demographics, anatomic location, stage, chemo- therapy, necrosis rate, recurrence and metastatic rates were recorded; Kaplan-Meier survival rates were estimated. The median age was 54 years (range, 12-86 years). Nineteen patients were female and eight patients were male. Median followup was 39.2 months (range, 0-218 months). Twenty-two patients received induction chemotherapy for a mean of four cycles (range, 2-6 cycles). Mean tumor necrosis was 63.5%. Seven patients had 90% necrosis; four of these patients died of their disease. The mean survival was 23 months, and the 5-year disease free survival estimate was 27.2%. Histologic response to chemotherapy did not correlate with survival. Patients who had a latency of greater than 10 years after radiation had a better prognosis. Unlike conventional osteosarcoma, response to chemotherapy (necrosis) did not have prognostic significance. Current chemotherapy regimens fail to impact survival in postradiation osteosarcoma.

Therapeutic study, level IV (retrospective comparative study).