Outcome of rare primary malignant bone sarcoma (RPMBS) treated with multimodal therapy: Results from the EUROpean Bone Over 40 Sarcoma Study (EURO-B.O.S.S)
Mené sur 113 patients atteints d'un sarcome osseux primitif rare traité par chirurgie en combinaison avec une chimiothérapie (âge : 40 à 66 ans ; âge médian : 52 ans ; durée médiane de suivi : 6,4 ans), cette étude évalue le taux de survie à 5 ans et la toxicité des traitements reçus
Background : Rare primary malignant bone sarcomas (RPMBS) account for 5%–10% of primary high-grade bone tumors and represent a major treatment challenge. The outcome of patients with RPMBS enrolled in the EUROpean Bone Over 40 Sarcoma Study (EURO-B.O.S.S) is presented. Methods : Inclusion criteria were as follows: age from 41 to 65 years and a diagnosis of high-grade spindle cell, pleomorphic, or vascular RPMBS. The chemotherapy regimen included doxorubicin 60 mg/m2, ifosfamide 9 g/m2, and cisplatin 90 mg/m2; postoperative methotrexate 8 g/m2 was added in case of a poor histologic response. Version 2.0 of the Common Terminology Criteria for Adverse Events, Kaplan–Meier curves, log-rank tests, and univariate Cox regression models were used. Results : In total, 113 patients were evaluable for analysis. The median patient age was 52 years (range, 40–66 years), and 67 patients were men. Eighty-eight tumors were categorized as undifferentiated pleomorphic sarcomas (UPS), 20 were categorized as leiomyosarcomas, three were categorized as fibrosarcomas, and two were categorized as angiosarcomas. Eighty-three of 113 tumors were located in the extremities. Ninety-five of 113 patients presented with no evidence of metastases. After a median follow-up of 6.8 years (interquartile range [IQR], 3.5–9.8 years), the 5-year overall survival rate for patients with localized disease was 68.4% (IQR, 56.9%–77.5%), and it was 71.7% (IQR, 58.1%–81.6%) for patients with UPS and 54.9% (IQR, 29.5%–74.5%) for patients with leiomyosarcoma. Grade III–IV hematologic toxicity was reported in 81% patients; 23% had grade II–III neurotoxicity, and 37.5% had grade I–II nephrotoxicity. Five-year overall survival was significantly better for patients with localized disease, for patients who obtained surgical complete remission, and when the primary tumor was located in the extremities. Conclusions : The survival of patients who had RPMBS in the current series was similar to that of age-matched patients who had high-grade osteosarcoma treated according to the same protocol. An osteosarcoma-like chemotherapy may be proposed in patients who have RPMBS.
Cancer 2023