cs.CVMar 16, 2026

A Comprehensive Benchmark of Histopathology Foundation Models for Kidney Digital Pathology Images

Authors: Harishwar Reddy Kasireddy, Patricio S. La Rosa, Akshita Gupta, Anindya S. Paul, Jamie L. Fermin, William L. Clapp, Meryl A. Waldman, Tarek M. El-Ashkar, +7 more

Organizations: Department of Electrical and Computer Engineering, University of Florida, Gainesville, FL, USA · Seed Production Innovation, Crop Science Division, Bayer Company, St. Louis, MO, USA · Division of Medicine – Quantitative Health, University of Florida, Gainesville, FL, USA · Department of Health Outcomes and Biomedical Informatics, University of Florida, Gainesville, FL, USA · Department of Pathology, Immunology and Laboratory Medicine, University of Florida College of Medicine, Gainesville, FL, USA · Kidney Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA · Indiana University School of Medicine, Indianapolis, IN, USA · Departments of Medicine, Washington University School of Medicine, St. Louis, MO, USA · Universidade de Coimbra, Coimbra, Coimbra District, Portugal · Department of Pathology and Laboratory Medicine, University of California at Davis School of Medicine, Sacramento, CA, USA · Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA · Department of Pathology, University of Michigan, Ann Arbor, MI, USA

Abstract

Histopathology foundation models (HFMs), pretrained on large-scale cancer datasets, have advanced computational pathology. However, their applicability to non-cancerous chronic kidney disease remains underexplored, despite coexistence of renal pathology with malignancies such as renal cell and urothelial carcinoma. We systematically evaluate 11 publicly available HFMs across 11 kidney-specific downstream tasks spanning multiple stains (PAS, H&E, PASM, and IHC), spatial scales (tile and slide-level), task types (classification, regression, and copy detection), and clinical objectives, including detection, diagnosis, and prognosis. Tile-level performance is assessed using repeated stratified group cross-validation, while slide-level tasks are evaluated using repeated nested stratified cross-validation. Statistical significance is examined using Friedman test followed by pairwise Wilcoxon signed-rank testing with Holm-Bonferroni correction and compact letter display visualization. To promote reproducibility, we release an open-source Python package, kidney-hfm-eval, available at https://pypi.org/project/kidney-hfm-eval/ , that reproduces the evaluation pipelines. Results show moderate to strong performance on tasks driven by coarse meso-scale renal morphology, including diagnostic classification and detection of prominent structural alterations. In contrast, performance consistently declines for tasks requiring fine-grained microstructural discrimination, complex biological phenotypes, or slide-level prognostic inference, largely independent of stain type. Overall, current HFMs appear to encode predominantly static meso-scale representations and may have limited capacity to capture subtle renal pathology or prognosis-related signals. Our results highlight the need for kidney-specific, multi-stain, and multimodal foundation models to support clinically reliable decision-making in nephrology.

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