Autologous Stem Cell Transplantation as First-Line Therapy in Peripheral T-Cell Lymphomas. A Prospective Multicenter Study.

Peripheral T-cell lymphomas (PTCL) are rare diseases representing only 10–15% of all non Hodgkin’s lymphomas and show a poor outcome following conventional chemotherapy. Long-term remissions are achieved in only 15 to 35% of patients following conventional chemotherapy. However, the impact of more aggressive therapeutic approaches such as high-dose therapy with autologous stem cell transplantation (ASCT) as first-line therapy is poorly defined mainly due to the lack of prospective PTCL-restricted studies. Therefore, in 2000 we initiated the first prospective PTCL-restricted multicenter study in PTCL. The results of the first 30 patients (pts) have recently been published. Here we update our data on all pts. entering the study.

Study design: Pts. < 65 years with PTCL of all subtypes without primary cutaneous lymphoma and ALK1+ anaplastic large cell lymphoma were included. Treatment consisted of 4–6 courses of CHOP followed by DexaBEAM or ESHAP regimens before collection of stem cells. Subsequently, pts. underwent total body irradiation (TBI) and high dose cyclophosphamide (60 mg/kg body weight) chemotherapy with ASCT.

Patient characteristics: From 6/00 to 7/05 75 pts. (65% male) with a median age of 50 years were enrolled. Main subtypes were Peripheral T-cell lymphoma not otherwise specified (NOS, 41%) and Angioimmunoblastic T-cell lymphoma (AIL, n= 31%). According to the Ann Arbor classification, 75% of the pts had stage III/IV disease. The International Prognostic Index (IPI) was low/low intermediate in 51% and high intermediate/high in 49% of pts, respectively.

Results: So far 65 pts are eligible for evaluation. Forty pts could be transplanted (62%). After a median follow-up of 10 months post-transplant 22 pts (42%) are in sustained remission and 8 pts (15%) have relapsed. Treatment-related mortality was 2/65 (3%, one secondary AML, one multiorgan failure). Twenty-five pts (38%) did not proceed to ASCT mainly due to progressive disease (n= 18). Treatment-related toxicity was comparable to other high-dose studies in B-cell lymphomas. The IPI does not seem to have a significant impact on response to therapy, progression during CHOP therapy, or relapse rate following ASCT.

Conclusion: Our data confirm the feasibility and efficacy of first line ASCT following myeloablative radiochemotherapy in PTCL. A sustained remission seems achievable for a significant proportion of pts. However, additional treatment strategies are required to prevent early progression before myeloablative therapy. Longer follow up is necessary to confirm long term remission rates.