The risk score based on the IRGs had similar sensitivity and specificity to a classifier proposed by Liu et al.17 Of 14 survival-associated IRGs, 5 have been reported in studies about osteosarcoma, such as a 2018 study by Han et al.18 CCL2 is an important chemokine that plays a critical role in cancer progression. The gene discussed is CCL2; the disease is osteosarcoma.