Allogeneic Stem Cell Transplantation (Allo-SCT) Following a Reduced-Intensity Conditioning (RIC) Regimen in Relapsed Peripheral T-Cell Lymphomas (PTCL): Results at 4 Year of Median Follow-up.

Abstract 875 Conventional therapies and autologous stem cell transplantation lead to disappointing results in relapsed PTCL, therefore allo-SCT has been investigated in the last years. There are evidence supporting the existence of a “graft-versus-PTCL” effect, but the majority of the studies have a limited number of patients with a short follow-up. We conducted a retrospective analysis on 53 patients (pts) affected by relapsed/refractory PTCL who received a RIC regimen followed by allo-SCT. The main histopathological subtypes were PTCL-not otherwise specified (PTCL-NOS, n=24), anaplastic large-cell lymphoma (ALCL, n=11), and angioimmunoblastic (AILD, n=6). The remaining cases were rare subtypes (n=12). Median age was 47 years (range, 15-64 years). Patients were allografted from matched related siblings (n=34, 64%) or alternative donors (n=19, 36%). The majority of pts had chemosensitive disease (n=39, 74%), received allo-SCT more than 12 months from diagnosis (n=38, 72%) and were treated with only 1 or 2 lines of therapy before transplantation (n= 37, 70%). At last follow-up (median 49 months, range 6-118), 29 pts are alive (55%, 26 in CR) and 24 died [n=20 for disease progression, n=4 for non-relapse mortality (NRM)]. The majority of relapsing patients (20 of 25, 80%) died at median time of 7 months after allo-SCT. The crude cumulative incidence (CCI) of relapse was 32% and 50% at 6 months and at 4-year after allo-SCT. The CCI of relapse was influenced by status of disease [chemosensitive versus chemorefractory: 41% versus 77% at 4 years (p 2: 40% versus 70% at 4 years (p Disclosures: No relevant conflicts of interest to declare.