Pb2440: autologous hematopoietic stem cell transplantation in lymphoma: a 10-year review of activity at the tunisian national bone marrow transplantation center

Topic: 22. Stem cell transplantation - Clinical Background: Intensive chemotherapy followed by autologous stem cell transplant (ASCT) is the treatment of choice for refractory and relapsed forms of lymphoma but can also be proposed as 1st line treatment in high risk non-Hodgkin’s lymphoma. Aims: We aimed to evaluate patients’ outcome after ASCT. Methods: We retrospectively analyzed the data from all lymphoma patients who underwent ASCT between 2012 and 2021. Results: A total of 162 lymphoma patients were included: Hodgkin’s Lymphoma (n=56) and Non-Hodgkin’s Lymphomas (n=106): Diffuse large B-cell lymphoma (DLBCL): n=76, T-Lymphoma: n=17, Mantle Cell Lymphoma: n=11 and Follicular Lymphoma: n=2. The median age at ASCT was 38 years (7 - 61). The sex ratio was 1.34. The median graft richness was 5.16 × 106 CD34/Kg (2.23-22.9). Median time to neutrophil engraftment after BEAM conditioning regimen, was d+11 (6-48) and median platelet engraftment was d+12 (8-56). The median length of hospitalization was 27 days (16 – 69). For Hodgkin’s lymphoma patients, the indication for ASCT was either refractory disease (n= 26) or relapse (n= 30). The median time between the last treatment and ACST was 50 days (21 days -7 months). Pre-transplant and 3months’ disease status was, respectively, complete response (CR) (27% vs 47%), partial response (PR) (58% vs 36%), and failure or progression (15% vs 17%). Overall survival (OS) was respectively 88.9% at 1 year, 82.3% at 2 years and 64.3% at 5 years. Event-free survival (EFS) was 73.6%, 69.8% and 57.2% at 1, 2 and 5 years. After a median follow-up of 15 months (10 days- 9.5years),, 11 patients (19.6%) died (NRM n=4, relapse n=7) within a median of 15 months (10 days - 59 months) after ASCT and 13 patients (23%) relapsed after a median of 6 months (2-41). Two patients had allogeneic stem cell transplantation. They are alive in complete remission. For patients with DLBCL, the ASCT was indicated in first-line in 59 patients (77.7%) and in second-line in 17 patients (refractory lymphoma: n=6, progression: n=2, relapse: n=9). The median time from last treatment to ACST was 2 months (14 days - 7 months). The pre-transplant and 3-months’ disease status was, respectively, CR (56% vs 54%), PR (37% vs 33%) and failure or progression (7% vs 13%). OS was respectively 90.1%, 88% and 80% at 1, 2 and 5 years. EFS was respectively 79.6%, 79.6% and 72.1% at 1, 2 and 5 years. After a median follow-up of 12 months (8 days-10years), 8 patients (10.5%) died (NRM n=3, relapse n=5), within a median of 5 months (14 days - 83 months) after ASCT and 12 patients (15.8%) relapsed within a median of 4 months (2-51). Conclusion: We observed survival rates comparable to those reported in the international data. Efforts must be made to improve pre-transplant disease status with the introduction of immunotherapies. Keywords: Autologous hematopoietic stem cell transplantation, Diffuse large B cell lymphoma, Hodgkin’s lymphoma