Immunoglobulin Light Chain Renal Amyloidosis Patients with t(11;14) Have Much More Possibility to be Present As Nephrotic Syndrome

Immunoglobulin Light Chain Renal Amyloidosis patients with t(11;14) have much more possibility to be present as nephrotic syndrome

Introduction：Systemic immunoglobulin light chain (AL) amyloidosis is a clonal plasma cell disorder characterized by organ dysfunction secondary to deposition of misfolded light chains. Approximately 70% of patients with AL amyloidosis have renal involvement presented with heavy proteinuria or nephrotic syndrome and can progressed to end-stage renal disease. We sought to explore the clinical characteristics and outcomes between patients presenting with or without nephrotic syndrome.

Methods:

A total of 37 patients of newly diagnosed AL amyloidosis with renal involvement between 2015/9/26 and 2023/11/30 were included in this single-center, retrospective observational study. The diagnosis of AL amyloidosis was confirmed by tissue biopsy. Exclusion criteria included known as prior AL amyloidosis related treatment, multiple myeloma, baseline end-stage renal disease, dialysis or renal transplant. Demographic and clinical characteristics, FISH results, along with outcomes including best hematologic response, renal response and overall survival (OS) were assessed. The definition of both hematological response and renal response was based on the International Myeloma Working Group (IMWG) criteria

Results：

37 participants were included for statistical analyses, including 24（64.9%）patients with nephrotic syndrome (AN group) and 13 patients（35.1%）without nephrotic syndrome (AM group). The two groups share a similar incidence rate of cytogenetic abnormalities, while the prevalence of t(11;14）was significantly higher in AN group than AM group (62.5% vs. 46.2%, p=0.027). Although the small number of patients with renal stage III (n=2) were enrolled, which were all classified in AN group.

Regardless of treatment regimen, there was no difference between the two groups in terms of hematologic remission. Compared with the AN group, a significantly higher proportion of deep renal remission （≥VGPR）were observed in AM group (53.8% vs. 20.8%, p＜0.001). Meanwhile, we classified the patients into four subgroups according to the different treatments, including bortezomib-based, melphalan-based, dara-based and others regimen groups. No statistical significance was found comparing different treatment groups due to the small sample size.

The median follow-up of the patients was 52.3 months. There was a tendency for the AM group to have longer OS compared with the AN group, but no statistical significance was achieved（75% vs. 61.5%，p =0.312），which needed to be confirmed in an cohort with expanded sample sizes.

Conclusions:

Nephrotic syndrome was more likely to be presented in AL amyloidosis patients with t(11;14), leading to a relatively poor organ response to chemotherapy.

No relevant conflicts of interest to declare.