Abstract: SA-PO1249
Kidney Biopsy in the Era of Immune Checkpoint Inhibitors: Safety, Diagnostic Heterogeneity, and the Case for a Biopsy-First Strategy
Session Information
- Onconephrology: Epidemiological Trends, Risk Stratification, and Clinical Outcomes
October 24, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Onconephrology
- 1600 Onconephrology
Authors
- Brito, Germana Alves, A C Camargo Cancer Center, São Paulo, SP, Brazil
- Pereira, Benedito J., A C Camargo Cancer Center, São Paulo, SP, Brazil
- Malheiros, Denise M., Universidade de Sao Paulo, São Paulo, SP, Brazil
- Fernandes, Lizieux Matos, A C Camargo Cancer Center, São Paulo, SP, Brazil
- Imanishe, Marina Harume, A C Camargo Cancer Center, São Paulo, SP, Brazil
- Baptista, Aline Lourenco, A C Camargo Cancer Center, São Paulo, SP, Brazil
- Andrade, Luis Andre, A C Camargo Cancer Center, São Paulo, SP, Brazil
- De Barros e Silva, Milton José, A C Camargo Cancer Center, São Paulo, SP, Brazil
Background
Kidney immune-related adverse events from immune checkpoint inhibitors (ICIs) are commonly attributed to acute interstitial nephritis (AIN), and biopsy is frequently deferred in severe AKI, leading to empiric immunosuppression without histologic confirmation
Methods
Retrospective, single-center observational study at AC Camargo Cancer Center (São Paulo, Brazil) including adults receiving ICIs who underwent native kidney biopsy (April 2023–January 2026). Indications: KDIGO stage ≥2 AKI, proteinuria >1g/day, or recurrent/refractory AKI despite empiric corticosteroids. We assessed biopsy safety, histopathologic diagnosis, management change, renal response (as defined as return of serum creatinine to within 25% of baseline value) and ICI rechallenge outcomes
Results
Twenty-one patients underwent biopsy (median baseline eGFR 75 mL/min/1.73 m2); two-thirds presented with KDIGO stage 3 AKI. Median time from ICI initiation to AKI was 22 weeks (range 2–270). Regimens: monotherapy (33%), ICI+chemotherapy (33%), dual ICI (19%), ICI+targeted therapy (14%). AIN was the most frequent diagnosis (57%); however, 43% had non-AIN pathology—acute tubular necrosis (19%), glomerular disease (podocytopathy, immune-complex GN), pyelonephritis, and diabetic nephropathy. Biopsy changed management in 11 (52%) patients, predominantly among combination regimens (73%), most commonly ICI+chemotherapy, table. No biopsy-related complications occurred. Objective renal response was achieved in 86%. Median corticosteroid duration was 6 weeks (range 2-16). ICI rechallenge occurred in 33% and was less frequent when biopsy had changed management (18% vs 50%)
Conclusion
Kidney biopsy was safe, practice-changing in over half of cases and revealed substantial diagnostic heterogeneity. Rechallenge rates differed markedly based on whether biopsy altered management, underscoring its role in oncologic decision-making. These findings support an early biopsy-driven strategy to guide immunosuppression and rechallenge decisions