MO135: Efficacy and Safety of Bortezomib Combined with Autologous Stem Cell Transplantation in the Treatment of MGRS

Abstract

Abstract BACKGROUND AND AIMS To evaluate the efficacy and safety of bortezomib combined with autologous stem cell transplantation (ASCT) in the treatment of monoclonal gammopathy of renal significance (MGRS). METHOD The clinicopathologic data of 16 patients with non-AL MGRS who received bortezomib combined with ASCT in Jinling Hospital of Nanjing University School of Medicine from February 2012 to June 2021 were retrospectively analysed. RESULTS Twelve patients were male and four were female, with a median age of 49 years, a median serum creatinine was 1.71 mg/ dL (1.45, 2.09) and a median eGFR wad 42.1 mL/min/1.73 m2 (29.0, 51.6). Renal pathological types included seven patients were light chain deposition disease, two patients were heavy chain deposition disease, one patient was light and heavy chain deposition disease, five patients were light chain proximal tubulopathy and one patient was proliferative glomerulonephritis with monoclonal immunoglobulin deposition. Sixteen patients received bortezomib-based induction therapy with a median three courses before transplantation. Stem cells were successfully collected from all patients and CD34 + cell counts were 4.4–13.55 × 106/kg (8.77 ± 3.29 × 106/kg). All patients had successful haematopoietic reconstitution, and a median time of achieving granulocyte count of 500/L was 10 (9, 10) days, and a median time of achieving platelet count of 20 000/L was 12 (11, 13) days. The major treatment complications during transplantation were mucositis (87.5%), diarrhoea (62.5%), fever (56.3%), and nausea and vomiting (18.8%); the other rare complications were acute kidney injury, skin rashes and liver function damage. Haematologic responses were achieved in 15 patients (93.8%), with 10 patients (62.5%) achieved complete responses, 3 patients (18.8%) achieved very good partial responses, 2 patients (12.5%) achieved partial responses, and 1 patient had no haematologic responses. Before treatment with ASCT, seven patients (43.8%) achieved partial response, of which four achieved complete response after ASCT, and one patient did not achieve hematologic response but achieved complete response after ASCT. A total of 12 patients (75%) achieved renal response before ASCT and 14 patients (87.5%) achieved renal response after ASCT. The median follow-up time was 43.5 months. One patient died during the follow-up due to infection, and one patient developed end-stage renal disease during the follow-up. Three patients relapsed, with a median time of 49 months. CONCLUSION Our data demonstrated that ASCT is a safe and effective treatment for rigorously selected non-AL MGRS patients, with few serious treatment complications and high haematological and organ response rates.