Enhancing prognostic guidance in renal light-chain amyloidosis: a new staging system incorporating pathological characters.

Abstract

Advancements in treatment regimens have led to improved outcomes in renal Immunoglobulin light-chain amyloidosis. Nevertheless, a subset of patients may still experience renal adverse events despite achieving hematologic very good partial response or better. This discrepancy may be attributed to the deposition pattern of amyloid in renal tissue. To enhance prognostic assessment, a staging system that incorporates both pathological characteristics and clinical indicators should be developed. Patients newly diagnosed through renal biopsy between January 1, 2017, and December 31, 2022, were included. The renal pathology of patients was evaluated according to amyloid score (AS). Risk factors for end-stage renal disease or renal progression were identified by thecompeting risk model, then to develop a renal staging system. The Concordance index (C-index), internal cross-validation and Decision Curve Analysis (DCA) were used to evaluate the performance of the new staging system. 74 patients were included, and 16 (21.6%) patients had end-stage renal disease or renal progression within 24.7 (11.9, 50.7) months. AS and estimated glomerular filtration rate (eGFR) were identified as independent risk factors and the staging system based on them, which the C-index was 0.81 (95%CI, 0.73-0.89), had greater improvement than previous staging systems. The internal cross-validation and DCA also confirmed its great clinical benefits. The AS demonstrated its prognostic significance in Chinese patients, and the novel renal staging system based on AS and eGFR may provide great prognostic guidance for these patients.