Introduction: Secondary sarcomas of bone are a rare group of usually high-grade malignant tumors developing over different pre-existing bone conditions, historically associated with worse prognosis than their primary counterpart. Purpose of this study was to investigate the factors affecting the outcome, with emphasis modern multi-modal management.

Methods: From approximately 30000 bone tumor cases filed at our Institution, 87 patients with secondary sarcoma were identified. Secondary chondrosarcomas were not included and all the patients had an high-grade lesion. Patients were divided in 3 groups: radiation induced sarcomas (29), sarcomas in Paget’s disease (34), and sarcomas in benign lesions (24). Of these patients, 67 were admitted for treatment while 20 were consultations; of the 67 patients admitted, 44 had stage II while 23 had stage III disease. There were 57 males and 30 females, average age was 52. Most common histotype was osteosarcoma (81). Treatment varied from none to combined multimodal management including chemotherapy and surgery.

Results: Cumulative survival is 37% at 10 years. Survival was affected by stage of disease (II=54%, III=0%; p< 0.00005), site (extremities 44%, pelvis-spine 0%; p< 0.00005), inclusion of surgery in the treatment plan (yes 51%, no 0%; p< 0.00005), and type of treatment (combined chemotherapy and surgery 56%, surgery 39%; p=0.07). No differences were noted between the 3 main etiologic groups.

Conclusions: Secondary sarcomas are a rare group malignant tumors with heterogeneous clinical features. While stage and site are still the most relevant prognostic factors, modern multimodal management including neoadjuvant chemotherapy and surgery seems to favourably affect the outcome.