TNF and cancer: C-reactive protein is an acute-phase protein synthesized in the liver in response to pro-inflammatory cytokines, primarily interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α).17Elevated CRP levels have been consistently associated with poor prognosis and increased metastatic potential in various cancers, including osteosarcoma.6, 18, 19, 20The significant association between elevated CRP levels and the presence of metastasis in the current study suggests that CRP may serve as a surrogate marker for the extent of systemic inflammation and tumor aggressiveness in osteosarcoma.