CD40 and synovial sarcoma: In contrast, elevated levels of CD40L receptor (OR = 0.85, 95% CI = 0.74–0.97, p = 0.019), Cystatin D (OR = 0.75, 95% CI = 0.59–0.96, p = 0.022), Monocyte chemoattractant protein-3 (OR = 0.79, 95% CI = 0.66–0.95, p = 0.011), Tumor necrosis factor (OR = 0.76, 95% CI = 0.61–0.95, p = 0.017), Tumor necrosis factor ligand superfamily member 14 (OR = 0.86, 95% CI = 0.74–0.99, p = 0.043), and Interleukin-2 (OR = 0.71, 95% CI = 0.52–0.98, p = 0.039) were associated with a reduced risk of SS, as demonstrated by the IVW method (Table S7).