Allogeneic Stem Cell Transplantation (Allo-SCT) for Relapsed/Refractory T Cell Lymphomas in Adults: A Survey from the Société Française de Greffe de Moelle et de Thérapie Cellulaire (SFGM-TC).

Background: Adult mature T-cell and NK-cell neoplasms include several lymphomas entities. Taken together, T- and NK- cell lymphomas represent 10–15 % of non-Hodgkin’s lymphoma in adults, presenting with aggressive behaviour and poor outcome (except for ALCL ALK positif lymphomas). Despite intensive chemotherapy including or not autologous stem cell transplantation upfront, a majority of patients experience relapse. Therefore, allo-SCT is an attractive second-line strategy. We retrospectively analyzed T-cell lymphomas patients (lymphoblastic lymphomas were systematically excluded) reported to the SFGM-TC registry and transplanted from an HLA identical sibling donor with or without myeloablative conditioning regimen.

Results: In the present intermediate report, we analysed 24 patients. Because of misdiagnosis, we excluded two cases. Among the 22 remaining patients, there were peripheral T-cell lymphoma NOS (PTCL) in 5 cases, angioimmunoblastic T-cell lymphoma (AITL) in 3 cases, anaplastic large cell lymphoma (ALCL) in 10 cases (ALK positif in 3 cases; negative in 2 cases and unknown in 5 cases; respectively), hepatosplenic g/d lymphoma (HSL) in 2 cases, T-cell granular lymphocytic leukemia (GLL) in 1 case and localized nasal NK/T cell lymphoma (NK/L) in one case. There were 15 males and 7 females. Median age was 38.5 years (15.5–54). All patients have been considered eligible for allo-SCT because of poor prognosis factors: HSL diagnosis in 2 cases, relapsed/refractory disease in 16 cases (including all ALCL cases) and/or failure to reach CR in 8 cases. Disease status at the time of transplantation was CR in 9 cases, PR in 7 cases and PD/refractory in 3 cases; respectively. All patients but 2 underwent myeloablative conditioning regimen prior to transplantation (TBI/EDX in 70%). The majority of patients (86%) received BMSC graft from related HLA-matched sibling donor. Median overall survival (OS) was 70 months for the all cohort. Median OS was not reached in the ALCL subgroup compared to 20 months for the non-ALCL subgroup. According to disease status, 7 out of 9 patients in CR at the time of transplantation are alive and in CR at the time of the analysis compared to 6 out of 13 in non-CR patients. Cause of death was AGVH in 2 cases, bacterial or fatal infections in 4 cases and relapse in 2 cases, respectively.

Conclusion: these preliminary results show that allo-SCT is a treatment of choice for refractory/relapsed T-cell lymphomas. Results are very encouraging in relapsed/refractory ALCL patients and highlight the role of graft versus T-cell lymphoma effect. Further analysis are required to identify prognosis factors and additional cases will be analyzed at the time of the meeting.