The major findings included that (1) OS patients had significantly higher serum EFEMP1 levels than the healthy controls, (2) an increase in the serum EFEMP1 levels was associated with lung metastasis in OS patients, (3) an increase in the serum EFEMP1 levels was associated with tumor progression in the animal model, and (4) there was a correlation between the serum EFEMP1 level and Enneking staging of OS. Here, EFEMP1 is linked to neoplasm.