Autologous Peripheral Blood Stem Cell Transplant for Relapsed or Refractory T-Cell Non-Hodgkin's Lymphoma Results in Inferior Long Term Survival when Compared to Relapsed or Refractory B-Cell Non-Hodgkin's Lymphomas.

Abstract

Autologous transplant has emerged as the standard of care for the treatment of relapsed B-cell non-Hodgkin's lymphomas (NHL). However, for the treatment of T-cell NHL, the role is not as clear. We report our experience with 24 patients with T-cell NHL who underwent autologous transplantation at time of first relapse. Lymphoma types were varied (peripheral T-cell = 8, lymphoblastic = 6, anaplastic large cell = 5, not otherwise specified = 5). All patients received CHOP as primary therapy, except one patient who received ProMACE/CytaBOM, one who received Stanford V, and two who received HyperCVAD. Patients had either relapsed disease (14 patients) or primary refractory disease (9 patients). One patient underwent autologous transplant as consolidation therapy. Mobilization regimens varied, consisting of dexamethasone, ifosphamide, etoposide, and cisplatin (DICE, 12 patients), dose intensive cyclophosphamide, etoposide, cisplatin (DICEP, 5 patients), cyclophosphamide/etoposide (3 patients), cyclophosphamide (2 patients), or other regimens (2 patients). Adequate collection of stem cells was seen in all but one case, which required bone marrow collection. The conditioning regimen used was BVAC (BCNU 600 mg/m2, etoposide 1600 mg/m2, cytarabine 24 g/m2, and cyclophosphamide 90 mg/kg) in 23 patients. One patient received melphalan conditioning. For the entire group, the overall survival at 3 years was 50%. This compares favorably with 336 relapsed B-cell NHL patients who underwent autologous transplant with the identical conditioning regimen (BVAC) in the same period of time (OS = 52%). At 5 years, the overall survival of the B-cell lymphoma group was stable at 49%. However, the overall survival for the T-cell NHL group declined to 30%. The primary cause of death post transplant was disease relapse. When divided among specific lymphoma subtypes, 3 of 8 patients with peripheral T-cell lymphoma, 4 of 5 patients with anaplastic large cell lymphoma, 3 of 6 patients with lymphoblastic lymphoma and 3 of 5 patients with other T-cell lymphoma subtypes remain alive. Although there are too few patients to draw any definite conclusions, it appears that autologous stem cell transplant for relapsed or refractory T-cell NHL results in similar 3-year overall survivals when compared to B-cell NHL using the same conditioning regimen. However, T-cell NHL appear to be associated with a higher late relapse rate which is reflected in the lower overall survivals at 5 years. Although there may be a benefit to autologous transplant in relapsed anaplastic large cell lymphomas, relapsed/refractory T-cell NHL had inferior long term overall survival compared to their B-cell counterpart transplanted with the same regimen. Novel approaches should be considered in the treatment of relapsed or refractory T-cell NHL.