A European treatment protocol for bone sarcoma in patients older than 40 years

Abstract

10516 Background: EUROpean Bone Over 40 Sarcoma Study (EURO-B.O.S.S.) is the first prospective multicenter international study for patients 41 - 65 years old with high-grade bone sarcoma. Methods: Patients with HG Osteosarcoma (OS), HG sarcoma NOS (S), Fibrosarcoma, MFH, Leiomyosarcoma, Dedifferentiated Chondrosarcoma (DCh) were included. Chemotherapy: Combinations of cisplatin/doxorubicin (CDP 100mg/m2/ADM 60mg/m2), ifosfamide/CDP(IFO 6g/m2/CDP 100mg/m2) and IFO/ADM (IFO 6g/m2/ADM 60mg/m2) were repeated three times (9 cycles). Surgery was planned after 3 cycles. Methotrexate (8g/m2) was postoperatively added in poor responders. Immediate surgery was allowed and 9 cycles with CDP, ADM, IFO were postoperatively given. Results: In December 2007, 140 patients were registered (median age 51 years). OS (51%), S (16%), and DCh (11%) were the more frequent histotypes. Synchronous metastases in 30 (21%) patients, central location of tumor in 45 (32%). Surgical complete remission (SCR) was achieved in 84% of patients, (localized 91%, metastatic 37%) without difference among the histology groups. One surgical-related and one chemotherapy-related death were reported. Grade 4 WBC and PLT incidence was 55% and 17%.Renal toxicity and peripheral neurotoxicity were reported in 16% and 20% of patients. With a median follow-up of 25 months (4–68) 3 year OS was 58% (95%CI 48–68%) [7% (95%CI 0–19%) without SCR]. In patients with SCR, 3 year OS and EFS were 46% (95%CI 9–83%) and 0% in case of synchronous metastases and 69% (95%CI58–80%) and 45% (95%CI33–57%) for localized patients; 50% (95%CI 29–71%) and 40% (95%CI 20–59%) for patients with central tumor, 73% (95%CI61–85%) and 44% (95%CI31–57%) for those with extremity tumor; 68% (95%CI 52–83%) and 46% (95%CI 32–54%) for OS, 64% (95%CI 42–85%) and 48% (95%CI 25–71%) for S, 48% (95%CI 13–82%) and 27% (95%CI 1–54%) for DCh. Conclusions: The protocol is feasible, but the chemotherapy-related toxicity is remarkable. Surgical complete remission is the main factor influencing survival. Central location and synchronous metastases are negative prognostic factors, but 50% 3-year OS can be achieved with aggressive local and systemic treatment. Osteosarcoma and high-grade sarcoma NOS benefit from chemotherapy more than patients with dedifferentiated chondrosarcoma. No significant financial relationships to disclose.