Allogeneic Stem Cell Transplantation in Angioimmunoblastic T-Cell Lymphoma (AITL): A Retrospective Survey from the Lymphoma Working Party (LWP) of the European Group for Blood and Marrow Transplantation (EBMT).

AITL is a rare peripheral T-cell lymphoma characterised by an aggressive behaviour, which primarily affects the elderly. Chemotherapy regimens fail to alter the high relapse rate and overall survival hardly exceeds 25% at 5 years. To date, there is no information on the potential role of allogeneic stem cell transplantation (allo-SCT) in the management of AITL. We report the outcome of 39 patients with a median age of 47 years (24–68), who underwent an allo-SCT between 1995 and 2004 for AITL, and were reported to the EBMT registry. The median time from diagnosis to transplant was 10 months (4–72). Thirty-four patients (87%) had previously received two or more treatment lines, and 16 patients (41%) a previous autologous SCT. Fifteen patients (38%) had a primary refractory disease, 13 (33%) were transplanted in partial remission and the remaining patients were in complete remission (CR) (mostly in 2^nd and 3^rd CR). Twenty-four patients were transplanted from an HLA-identical sibling and 15 from a matched unrelated donor. A myeloablative conditioning regimen (MAC) was used in 21 patients (cyclophosphamide + total body irradiation in 14), while 18 patients received fludarabine-based reduced intensity conditionings (RIC). Peripheral blood was the source of stem cells in 35 patients (90%). Three patients failed to engraft (one patient in the RIC group). Twenty-one patients (54%) developed acute graft versus host disease (grade I-II, n=16; grade III-IV, n=5). Twenty-eight patients (72%) achieved a CR after the allogeneic procedure. Nine patients died from transplant related mortality (TRM) and 5 patients from disease progression. The cumulative incidence of TRM at 12 months was 19% for the MAC and 26% for the RIC group. After a median follow-up for the surviving patients of 20 months (6–74), 25 patients are alive. Relapse rates at 1 and 3 years were estimated at 10% and 18% for the MAC and 16 and 20% for the RIC patients. Progression free survival rates at 3 years were 67% and 50% and the overall survival at the same time 71% and 56% for the MAC and RIC group of patients, respectively. Although follow up is rather short, these data suggest that allo-SCT results in good overall response and is associated with a low relapse rate in this group of poor risk heavily pre-treated and rather elderly group of AITL patients. Allo-SCT could be considered a therapeutic option for eligible high-risk AITL patients. Nevertheless, the impact of this approach should be further explored in prospective collaborative studies.