IL10 and renal cell carcinoma: In 69 patients with advanced RCC receiving first‐line ICI, those with baseline serum IL‐10 >4.3 ng/mL (n = 9) had significantly shorter mPFS (5.2 months vs. not reached at 30 months) and mOS (13.9 months vs. not reached at 30 months) than patients with levels <4.3 ng/mL (n = 60) in multi‐variate analyses, underscoring IL‐10 as an independent prognostic factor of survival.34