Lung metastases pattern in limb osteosarcoma: A population-based study from 2010 to 2018

Osteosarcoma (OS) is one of the most prevalent malignant bone tumors. The proportion of limb OS is relatively high, and lung metastases (LM) are one of the most prevalent metastatic types. A total of 1694 new cases of limb OS were identified in the surveillance, epidemiology and end results (SEER) database from 2010 to 2018. Cox regression analyze was performed to identify prognostic factors for limb OS with LM, and univariate and multivariate logistic regression analyses were used to assess risk factors for LM. Kaplan-Meier analysis was performed to calculate overall survival for LM, and a log-rank test was used for comparison. A total of 287 patients (16.94%) were diagnosed with limb OS with LM. 25 to 59 years old (odds ratio, OR 0.68; 95% confidence interval, CI: 0.46-0.99), larger than 100 mm tumors (OR 3.65, 95% CI: 1.54-8.64), telangiectatic osteosarcoma type (OR 0.24, 95% CI: 0.07-0.81), central osteosarcoma type (OR 0.44, 95% CI: 0.19-0.99), T2 stage (OR 2.59, 95% CI: 1.18-5.69), N1 stage (OR 7.79, 95% CI: 3.90-15.56), presence of bone metastases (OR 4.58, 95% CI: 2.43-8.63) and surgical treatments of primary site (OR 0.22, 95% CI: 0.14-0.33) were significant correlations with lung metastases. Elderly age, black race and absence of surgery were harmful for survival. Age between 25 and 59 years, telangiectatic osteosarcoma and central osteosarcoma were identified as high-risk factors in limb OS patients with LM, and surgical treatment of the primary site significantly increased the survival rate of LM in these patients.