Update on the Assessment of Glomerular Filtration Rate in Patients with Cancer

Kidney360. 2025 Feb 24. doi: 10.34067/KID.0000000736. Online ahead of print.

Abstract

Accurate assessment of glomerular filtration rate (GFR) is key in patients with cancer, to guide drug eligibility, adjust dosing of systemic therapy, and minimize the risks of undertreatment and systemic toxicity. Several aspects of GFR evaluation in patients with cancer have been unclear, such as the choice of the GFR estimating equation and the overall lack of data on the reliability of new filtration markers, such as cystatin C. This uncertainty has led to concerns that inaccurate GFR estimation may have a large impact on clinical practice and research. Recent data have brought important developments to the field. The new and timely KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease raised important considerations and provided guidance on key aspects of GFR evaluation in patients with cancer. The guidelines cover valid estimating equations, incorporation of cystatin C in GFR estimation, drawbacks of using race, and acknowledge that non-GFR determinants of filtration markers may be prominent in certain patients, reducing the accuracy of GFR estimating equations, prompting greater utilization of GFR measurement. The aim of this review is to summarize advances in GFR evaluation in patients with cancer, considering the new KDIGO guidelines and other recent data.