(OP 85) Donor Lymphocyte Infusion in Patients with Haematological Diseases

Donor lymphocyte infusion (DLI) after allogeneic haematopoietic transplantation (alloHT) is an effective therapy for some patients with recurrent haematological diseases; in high risk patients with mixed chimerism it has been used to prevent relapse. Delayed lymphocyte add-back after transplants with selection of CD34+ cells prevent graft failure, decrease risk of relapse and graft-versus-host disease (GVHD). The aim of this review was to study efficacy, toxicity and long-term outcome. We studied 54 patients(35 male/19 female) between 1994 and 2007; median age:32.5(7-59) years old. Diagnosis: Chronic Myeloid Leukemia(CML) 20/Acute Leukemia(AL) 20/Multiple Myeloma (MM) 6/others 8. Graft source: peripheral blood 46/bone marrow 9 (one also 2 blood cords); 4 donors unrelated. Conditioning regimen: myeloablative 38/reduced intensity 16. T-cell depletion of the graft: 25. GVHD prophylaxis: single agent 20/ double 34. Median CD34+ and CD3+ cells infused with the graft: 6.71(0.62-13.43) and 0.31(0.01-596) respectively. DLI was therapeutic in 42, pre-emptive in 5 and as T cell add-back in 7. Median CD3+ lymphocytes infused: 1 x 10 super(7) kg in 71% of DLI. Median interval transplant-first DLI: 8 months (1-60). Others therapies for relapse: imatinib-dazatinib 10/chemotherapy 9/second alloHT 6/others 3. Thirty-seven patients developed GVHD. Patients alive: 31 (22 complete remission/9 disease); main cause of death: disease progression. There was remission in 16 of therapeutic DLI (12/19CML; 2/2AL; 1/5MM; 1/2others), 5 months. This form of adoptive cell therapy is a therapeutic option in selected patients after alloHT, with better results in CML. Overall survival after 1st DLI was 50.4% ( plus or minus 8.2%) at 8 years. GVHD was the most frequent complication, otherwise it was well tolerated.