Upfront Allogeneic-Stem Cell Transplantation for Patients with Non-Localized Untreated Peripheral T-Cell Lymphoma: An Intention-to-Treat Analysis from a Single Center

Background. Peripheral T-cell lymphomas (PTCLs) are rare and heterogeneous diseases with dismal outcome when treated with chemotherapy alone. Because allogeneic stem cell transplantation (allo-SCT) can cure relapse-refractory patients, we hypothesised that upfront allo-SCT may be less toxic and provide a better outcome. Therefore, all patients that presented with advanced PTCL in our institution at diagnosis were scheduled to undergo upfront allo-SCT after induction chemotherapy.

Patients and methods. The aim of the present work was to assess the feasibility and toxicity of upfront allo-SCT. From 2004 to 2012, 49 newly diagnosed PTCL patients were scheduled to receive upfront allo-SCT. An HLA-matched donor was found for 42 patients: related to the patient in 15 cases, unrelated in 20 cases, and suitable cord blood units were used in seven cases.

Results. After induction chemotherapy, 17 patients reached complete remission and 29 (60%) proceeded to upfront allo-SCT. For all patients, the one and two-year overall survival (OS) rates were 59% (CI95%; 47-75) and 55 % (CI95%; 43-71), respectively. The most frequent reason we did not proceed to allo-SCT was disease progression or insufficient response after induction. For transplanted patients, the one- and two-year OS were 76% (CI95%; 62-93) and 72.5% (CI95%; 58-91), respectively. Toxicity related mortality one year after allo-SCT was only 8.2% (CI95%; 0-18.5). The two-year progression-free survival (PFS) rate of patients who did not proceed to allo-SCT (n= 20) was below 30%. The disease status at the time of transplantation was a strong predictive marker for both PFS and OS in transplant patients.

Conclusions. Upfront allo-SCT in PTCLs is feasible with low TRM, and it provides long-term disease control. However one third of patients remain chemo-refractory, and thus, new therapeutic approaches are warranted. The role of upfront allo-SCT compared to other therapeutic approaches in PTCLs requires investigation in randomized studies.