Prognosis of extremity osteosarcoma in patients aged 40–60 years: A cohort/case controlled study at a single institute

BackgroundThe outcome of older osteosarcoma patients with multi-disciplinary management has not been clearly defined.MethodsWe conducted a cohort (n = 375) and a case–control (n = 78) study on 26 older age patients (40–60 years) with localized osteosarcoma of extremity. In the case–control study, controls were matched for location and initial tumor volume.ResultsCompared to 349 younger patients, older age patients showed an osteolytic pattern on plain radiographs (P = 0.05), fibroblastic subtype (P < 0.01), and poor histologic response (P = 0.03). Multivariate analysis revealed that a large absolute tumor volume (P < 0.01), a tumor location in the proximal humerus (P = 0.02), and a poor histologic response to preoperative chemotherapy (P < 0.01) independently predicted poorer metastasis-free survival. However, an older age showed marginal significance (P = 0.09). A case–control study showed a higher proportion of the fibroblastic subtype and poor histologic response in the case group. Five-year metastasis-free survival rates for the 26 cases and 52 controls were 40.1 ± 10.1% and 61.5 ± 6.8%, respectively (P = 0.02).ConclusionsOlder age osteosarcoma patients showed an unfavorable histologic response to chemotherapy and lower survival than younger patients. Nevertheless, a further larger-scale study is required to confirm our observations.