Allogeneic hematopoietic stem cell transplantation in patients with diffuse large B cell lymphoma relapsed after autologous stem cell transplantation: a GITMO study.

Patients who relapse after an autologous hematopoietic stem cell transplantation (SCT) have a very poor prognosis. We have retrospectively analyzed diffuse large B cell lymphoma patients who underwent an allo-SCT after an auto-SCT relapse reported in the Gruppo Italiano Trapianto di Midollo Osseo (GITMO) database. From 1995 to 2008, 3449 autologous transplants were reported in the GITMO database. Eight hundred eighty-four patients relapsed or progressed after transplant; 165 patients, 19% of the relapsed patients, were treated with allo-transplant. The stem cell donor was related to the patient in 108 cases. A reduced intensity conditioning regimen was used in 116. After allo-SCT, 72 patients (43%) obtained a complete response and 9 obtained a partial response with an overall response rate of 49%; 84 patients (51%) experienced rapid progression of disease. Ninety-one patients died, 45 due to disease and 46 due to treatment-related mortality. Acute graft-versus-host disease was recorded in 57 patients and a chronic GvHD in 38 patients. With a median follow-up of 24 months (2-144) after allo, overall survival (OS) was 39%, and after a median of 21 months (2-138) after allo, progression-free survival (PFS) was 32%. Multivariate analysis indicated that the only factors affecting OS were status at allo-SCT, and those affecting PFS were status at allo-SCT and stem cell donor. This retrospective analysis shows that about one-fifth of patients with diffuse large B cell lymphoma who experience relapse after autologous transplantation may be treated with allogeneic transplantation. Moreover, the only parameter affecting either OS or PFS was the response status at the time of allo-SCT.