DP109 | AUTOLOGOUS TRANSPLANT IN PLASMA CELL DISORDERS WITH END STAGE RENAL DISEASE. TEN YEARS EXPERIENCE AT "PROGRAMMA TRAPIANTI METROPOLITANO" P. NAGAI.

BACKGROUND. Autologous stem cell transplant (ASCT) is a well-established consolidation strategy for patients (pts) with Plasma Cell Disorders (PCD). However, its use in advanced chronic kidney disease (CKD) remains controversial due to increased risk of morbidity and transplant-related mortality (TRM). Patients with end-stage renal disease (ESRD) are often undertreated and frequently do not receive standard therapy. METHODS. In December 2014, we developed a PTM ASCT protocol for PCD with ESRD, integrating a fixed dialysis schedule. After standard induction, peripheral blood stem cells (PBSC) were mobilized with cyclophosphamide (CY) 1.5–2 g/m² and G-CSF 5 µg/kg/day starting on D+3. Patients received a reduced-conditioning regimen with melphalan 140–180 mg/m² on D-3, dialysis and hydration on D-2, hydration on D-1, and dialysis pre ASCT on D0. All pts received G-CSF starting from D+1. RESULTS. From December 2014 to December 2024 a total of 37 ASCT were performed in 28 multiple myeloma (MM) pts and 2 pts affected by light chain disease. Twelve pts (40%) had ESRD requiring dialysis two to three times per week. Median age at diagnosis was 61 ys (range 34-71); median age at transplant was 62 ys (range 37-72). Cytogenetic data, available for 18 pts, showed 16 standard-risk (89%) and 2 high-risk (11%) cases. Twenty-four pts (80%) underwent ASCT as consolidation after first-line therapy with either bortezomib-thalidomide-dexamethasone (VTD) (22 pts, 73%) or daratumumab-VTD (2 pts, 7%); 6 pts (20%) refractory to first-line, were transplanted after second or third-line therapy. Stem cell collection was successful in all the pts; 3 (10%) required plerixafor. Median PBSC collected was 6.9×10⁶ CD34+cells/kg (range 2.5–15). Median PBSC infused was 3.8×10⁶ CD34+cells/kg (range 2-10.1). Median neutrophil engraftment time was 10 days after ASCT (range 8-21). Tandem ASCT was performed in 4 pts (13%) while 3 pts (10%) received a second ASCT at relapse. Treatment-related mortality was 5.4% (2 cases) due to sepsis and cardiac arrest, both pts had ESRD. Median progression free survival (PFS1) was 29 months (mo) (range 8-104). Three pts (10%) underwent a second ASCT after relapse; median PFS2 was 18 mo (range 16-48). Median overall survival was 69.5 mo (range 11-189) with 19 pts (63%) still alive at data cutoff. Seven pts died of disease progression, and one of secondary acute myeloid leukemia. CONCLUSION. Our protocol is safe and enables standard therapy in PCD patients with ESRD.