CST3 and cancer: It was observed that versions including serum creatinine (1−P30: 10.0 [8.3%–11.7%]) and combining creatinine and cystatin C (1−P30: 5.3 [4.1%–6.4%]) presented optimal performance.39 Although this study did not assess the effect of removing race on drug dosing or eligibility, these results support the KDIGO recommendations of removing race from GFR estimation in patients with cancer.