Metastasectomy of Pulmonary Metastases from Osteosarcoma: Prognostic Factors and Indication for Repeat Metastasectomy

Purpose. To identify prognostic factors for metastatic osteosarcoma patients and establish indication for repeat metastasectomy. Methods. Data from 37 patients with pulmonary metastasis from osteosarcoma who underwent metastasectomy in our institute from 1979 to 2013 were retrospectively reviewed. Results. Prognostic factors analyzed were age, sex, maximal diameter of the tumor at first pulmonary metastasectomy, total number of resected pulmonary metastases at first metastasectomy, number of surgeries, and disease free interval. In our analysis, characteristics associated with an increased overall survival were age > 15 years and fewer metastases (≤3). Of the 37 patients, 13 underwent repeat metastasectomy after the first metastasectomy. Of the 7 patients that underwent only two metastasectomies, three remained disease-free. In contrast, all six patients that underwent three or more metastasectomies died of relapse. Patients who had five or less lesions at second metastasectomy showed better survival compared to those who had six or more lesions. Conclusion. Age > 15 years and number of metastases at first metastasectomy were independent prognostic factors. Metastasectomy may provide curative treatment even in cases requiring repeat surgery. The number of metastases at second metastasectomy may be a potential predictor of the need for repeat surgery.