Glomerular Filtration Rate Estimation Using β2-Microglobulin and β-Trace Protein in Adults With Solid Tumors: A Prospective Cross-Sectional Study

Verônica T Costa E Silva; Luiz A Gil Jr; Lesley A Inker; Renato A Caires; Elerson Costalonga; George Coura-Filho; Marcelo T Sapienza; Gilberto Castro Jr; Maria Dp Estevez-Diz; Dirce Maria T Zanetta; Leila Antonângelo; Lia Marçal; Hocine Tighiouart; Shiyuan Miao; Paul Mathew; Andrew S Levey; Emmanuel A Burdmann

doi:10.1053/j.ajkd.2024.01.532

Glomerular Filtration Rate Estimation Using β₂-Microglobulin and β-Trace Protein in Adults With Solid Tumors: A Prospective Cross-Sectional Study

Am J Kidney Dis. 2024 Mar 25:S0272-6386(24)00684-X. doi: 10.1053/j.ajkd.2024.01.532. Online ahead of print.

Authors

Verônica T Costa E Silva¹, Luiz A Gil Jr², Lesley A Inker³, Renato A Caires⁴, Elerson Costalonga⁴, George Coura-Filho⁵, Marcelo T Sapienza⁶, Gilberto Castro Jr⁷, Maria Dp Estevez-Diz⁷, Dirce Maria T Zanetta⁸, Leila Antonângelo⁹, Lia Marçal⁹, Hocine Tighiouart¹⁰, Shiyuan Miao³, Paul Mathew¹¹, Andrew S Levey³, Emmanuel A Burdmann¹²

Affiliations

¹ Serviço de Nefrologia, Instituto do Câncer do Estado de São Paulo, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, BR; LIM 16, Serviço de Geriatria, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, BR. Electronic address: veronica.torres@hc.fm.usp.br.
² LIM 66, Serviço de Geriatria, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, BR.
³ Division of Nephrology, Tufts Medical Center, Boston, Massachusetts, United States of America.
⁴ Serviço de Nefrologia, Instituto do Câncer do Estado de São Paulo, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, BR.
⁵ Serviço de Medicina Nuclear, Instituto do Câncer do Estado de São Paulo, Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, BR.
⁶ Radiology and Oncology Department, Instituto do Câncer do Estado de São Paulo, Faculdade de Medicina da Universidade de São Paulo, São Paulo, SP, BR.
⁷ Serviço de Oncologia Clínica, Instituto do Câncer do Estado de São Paulo, Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, BR.
⁸ Department of Epidemiology, School of Public Health, University of São Paulo, São Paulo, SP, BR.
⁹ LIM 03, Division of Clinical Pathology, University of São Paulo Medical School, São Paulo, SP, BR.
¹⁰ Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, Boston, Massachusetts, Tufts Clinical and Translational Science Institute, Tufts University, Boston, Massachusetts, United States of America.
¹¹ Division of Hematology-Oncology, Tufts Medical Center, Boston, Massachusetts, United States of America.
¹² LIM 12, Faculdade de Medicina da Universidade de São Paulo, São Paulo, SP, BR.

PMID: 38537905
DOI: 10.1053/j.ajkd.2024.01.532

Abstract

Rationale & objective: β_2-microglobulin (B2M), and β-trace-protein (BTP) are novel endogenous filtration markers that may improve the accuracy of estimated glomerular filtration rate (eGFR) beyond creatinine and cystatin C (eGFR_cr-cys), but they have not been assessed in patients with cancer.

Study design: Cross-sectional analysis.

Setting & participants: Prospective cohort of 1,200 patients with active solid tumors recruited between April 2015 and September 2017.

Exposure: CKD-EPI equations without race combining B2M and/or BTP with creatinine with or without cystatin C (2-, 3- or 4-marker panel eGFR).

Outcomes: Performance of equations compared to eGFR_cr-cys. Non-GFR determinants of serum B2M and BTP (S_B2M, and S_BTP, respectively). mGFR was determined using the plasma clearance of ⁵¹Cr-EDTA.

Analytical approach: Bias was defined as the median of the differences between mGFR and eGFR. 1-P₃₀ was defined as the percentage of estimates that differed by more than 30% from the mGFR (1-P₃₀). Linear regression was used to assess association of clinical and laboratory variables with S_B2M, and S_BTP after adjustment for mGFR.

Results: Mean (SD) age and mGFR were 58.8 (13.2) years and 78.4 (21.7) ml/min/1.73 m², respectively. Performance of the 3-marker and 4-marker panel equations was better than eGFR_cr-cys (lesser bias and 1-P₃₀). Performance of 2-marker panel equations was as good as eGFR_cr-cys (lesser bias and similar 1-P₃₀). S_B2M and S_BTP were not strongly influenced by cancer site.

Limitations: Participants may have had better clinical performance status than the general population of patients with solid tumors.

Conclusions: B2M and BTP can improve the accuracy of eGFR and may be useful as confirmatory tests in patients with solid tumors, either by inclusion in multi-marker panel equation with creatinine and cystatin C, or by substituting for cystatin C in combination with creatinine.

Keywords: cancer patients; estimating equations; β(2-)microglobulin (B2M); β-trace-protein (BTP) glomerular filtration rate (GFR).