Osteosarcoma as a second or later malignancy: Presentation, treatment, and survival of 198 patients from the Cooperative Osteosarcoma Study Group
Year: 2026
Type: article
Study design: Observational Study
Abstract: BACKGROUND: More cancer survivors face secondary malignant diseases, including osteosarcoma. Due to its rarity, data on prognostic factors and outcomes are scarce. METHODS: We analysed the Cooperative Osteosarcoma Study Group database (1980-2022) for patients with osteosarcoma as a second or later malignancy (OS-SMD). To limit immortal-time bias, achievement of macroscopic complete remission (CR) was modelled as a time-dependent exposure in a Cox proportional hazards model adjusted for age, tumour site, and metastatic status at diagnosis. Postsurgical disease-free survival (DFS) in patients achieving CR was analysed in a competing-risks framework. RESULTS: Of 198 patients, 93% had osteosarcoma as a second malignancy; 6% and 1% had it as a third or fourth malignancy, respectively. Tumour locations included extremities (43%), trunk (35%), and craniofacial (22%). Median follow-up was 6.5 years (95%CI 5.2-8.2), and 93/198 patients died. The median overall survival was 5.5 years (95%CI 4.1-10.7). Five- and 10-year overall survival were 52.6% (95%CI 45.3-61.1) and 40.5% (95%CI 32.7-50.2), respectively. Achievement of CR was strongly associated with lower mortality (HR 0.33; 95%CI 0.19-0.56; P < 0.001), as was extremity versus trunk localisation (HR 0.49; 95%CI 0.29-0.84; P = 0.009). Metastatic disease at diagnosis was associated with higher mortality (HR 2.17; 95%CI 1.22-3.86; P = 0.008). A sensitivity analysis with surgery as a time-dependent exposure produced concordant results (HR 0.47; 95%CI 0.23-0.98; P = 0.045). Among 144 CR achievers with evaluable DFS time, the cumulative incidence of recurrence was 41.4% (95%CI 32.9-49.7) at 3 years and 47.0% (95%CI 38.1-55.4) at 5 years. CONCLUSIONS: Achieving CR is strongly associated with long-term survival in OS-SMD, supporting curative-intent treatment despite high recurrence risk. Residual confounding from the observational design cannot be excluded.
Source: European Journal of Cancer
Authors: Alexandru A. Sabo, Stefanie Hecker-Nolting, Stefan S. Bielack, Matthias Kevric, Benjamin Sorg, Mihnea P. Dragomir, Thekla von Kalle, Leo Kager, Michaela Nathrath, Claudia Rossig, Florian Babor, Reinhard Windhager, Judith S. Hecker, Christoph K.W. Deinzer, Peter Reichardt, Markus Metzler, Martin Benesch, Gerda Hofmann-Wackersreuther, Martin Ebinger, Claudia Blattmann
Institutions: Olgahospital, Klinikum Stuttgart, University of Tübingen, University Hospital Münster, German Cancer Research Center, Humboldt-Universität zu Berlin, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Freie Universität Berlin, Charité – Universitätsmedizin Berlin, St Anna Children's Hospital, St. Anna Children's Cancer Research Institute, Medical University of Vienna, TUM Klinikum, Klinikum Kassel, Technical University of Munich, University of Münster, Düsseldorf University Hospital, Universitätsklinikum Tübingen, Helios Hospital Berlin-Buch, Universitätsklinikum Erlangen, Medical University of Graz, Nuremberg Hospital, University Children's Hospital Tübingen
Language: English
Subfield: Oncology
Field: Medicine
Domain: Health Sciences
Open Access status: hybrid
Estimated APC paid: $4,270
OpenAlex ID: W7224785380