Allograft for myeloid malignancies in the year of 70 years old and beyond: No impact of pre-graft immune, nutritional and inflammatory status on outcome.

Abstract Background: The applicability of allogeneic stem cell transplantation (Allo-SCT) in elderly patients is debated and remains challenging. Beyond age and comorbidities, nutritional and inflammatory status has been poorly studied in these patients (Miyazaki, TCT 2024). Material and Methods: This was a retrospective monocentric study aiming to describe the overall survival (OS) of patients allografted during or after their 70th year (y) of life. Secondary objectives were progression free survival (PFS), GVHD free-relapse free survival (GRFS), non-relapse mortality (NRM), relapse incidence (RI), the number of days hospitalized for complications during the first post-transplant year (excluding rehabilitation stays), as well as the impact of the pre-graft immune, nutritional and inflammatory status. For immune status, we considered total lymphocytes, monocytes, CD3+, CD4+ and CD8+ T cells as well as B and NK cells and gamma globulin rate. Albumin was considered for the nutritional status at transplant. For the inflammatory status, we considered three markers (ferritin, C Reactive Protein CRP and fibrinogen) and four composite scores : CAR (CRP/albumin), CFA (CRP x fibrinogen/albumin), Glasgow prognostic score (GPS) and modified GPS (mGPS). GPS and mGPS were scored 0 to 2 based on CRP ( 1 mg/dL) and albumin ( 3.5 g/dL) levels, as previously described (Shibasaki, Clin Transplant 2017). Pre-transplant blood samples were obtained routinely within 1 month before initiation of the conditioning regimen. Data were recorded up to June 2025 and all living patients gave non opposition informed consent. The study was approved by the Ethic Review Board of our institution. Statistical analyses were performed in July 2025 using R version 4.2.2. Results: Between January 2013 and December 2023, 58 patients with a median age of 70.3y (IQR 69.9-71.0) were identified. Age at transplant was 69y for 16 (all ≥69.5y), 70 for 26, 71 for 6, 72 for 7 and 73 for 3. Most were transplanted for AML (n=24), followed by MDS (n=17), MPN (n=9) and MDS/MPN (n=8). Nineteen underwent upfront transplant while 22 and 17 had prior intensive and non-intensive chemotherapy, respectively. Among pre-treated patients (n=39), 32 were in CR at time of transplant. Most donors were MUD (n=36), followed by haploidentical (n=13), sibling (n=7), and other (n=2). With a median follow up of 66.5 months (95%CI: 44.9-81.8), 2y OS, PFS, GRFS, NRM and RI were 64% (52-77), 57% (45-71), 43% (32-58), 29% (18-42) and 14% (6.5-24), respectively. At 5 years it was 47% (35-64), 42% (31-59), 29% (19-45), 39% (26-53) and 18% (9.2-30), respectively. Day-100 acute grade 2-4 and 3-4 GVHD and 2-year extensive chronic GVHD were 29% (18-41), 14% (6.4-24) and 21% (11-33) respectively. Nutritional status was good, with only one patient with hypoalbuminemia. Most patients had elevated ferritin (83%), while elevated CRP and fibrinogen were observed in 45% and 28% of patients, respectively. Median CFA and CAR were both 0.00; and GPS and mGPS scores were 0 in 80% and 81% of patients. None of these markers influenced OS, PFS, GRFS, NRM or RI. All patients had at least one immune marker below normal; lymphopenia was observed in 71%, B cell and NK cell lymphopenia in 74% and 52%; and hypogammaglobulinemia in 7%. None of the immune markers impacted post-transplant outcomes. The median number of days spent in hospital for complications during the first post-transplant year was 9.5 (IQR 0-27.25; range 0-226). In multivariate analysis, AML (vs. other myeloid neoplasms) was the only factor associated with better OS (HR 0.38, 95%CI:0.16-0.91, p=0.031). Use of a non-matched donor was associated with longer hospitalization for the transplant procedure, while non-CR status predicted longer cumulative hospitalization for complications during the first post-transplant year (OR 11.87, 95%CI:1.74-94.44, p=0.007). Older age was associated with fewer hospital days during that time (OR 0.62, 95%CI:0.42-0.96, p=0.049), suggesting a selection bias towards fitter elderly patients. Conclusion: This retrospective monocentric study showed encouraging survival in patients transplanted in their seventies for myeloid malignancies, suggesting that age up to 75 years should not be considered an exclusion criterion for such procedure. However, the uniformly good nutritional status reflects in part a selection for transplant eligibility. Finally, pre-transplant immune deficiency and systemic inflammation had no impact on outcomes.