Prognosis of Primary Osteosarcoma in Elderly Patients: A Comparison between Young and Elderly Patients

Objectives: Osteosarcoma is the most common malignant bone tumor in childhood. Although a poorer prognosis has been described in older patients, few reports have focused solely on primary osteosarcoma. We evaluated the clinical features of elderly patients with primary osteosarcoma. Materials and Methods: Ninety-four patients were included in this retrospective study, and we divided them into 2 groups (older patients and younger patients) based on a cut-off age of 40 years. The patients' information, including age, tumor type, location, presence of metastasis, American Joint Committee on Cancer (AJCC) stage, treatment-related factors, local and distant relapse, and outcome, was collected. We compared the clinical courses between the 2 groups in all and only deceased patients. Results: In all patients, the frequency of chemotherapy in the older group was significantly lower than in the younger group (p < 0.001), and tumors were more frequent in axial bone in the older patients (p = 0.041). Only in patients with surgical treatment, histological effectiveness after chemotherapy in the older group was lower than in the younger group (p = 0.041). The older patients showed a poorer prognosis (p = 0.031). However, the 5-year overall survival rate in the older patients was more favorable than that in the younger patients only among deceased patients (p = 0.032). Only the existence of metastasis affected the prognosis in older patients (p = 0.012). Conclusion: Primary osteosarcoma in elderly patients showed a high incidence of axial bone involvement, a low rate of chemotherapy, and resistance to chemotherapy. Although the final life prognosis is poor, survival may be relatively prolonged. (C) 2019 The Author(s) Published by S. Karger AG, Basel