Frontline Allogeneic and Autologous Hematopoietic Cell Transplant for Peripheral T-Cell Lymphomas (PTCLs): A Comparison Study Between Conventional Chemotherapy and Hematopoietic Cell Transplant from a Chinese Center
Authors: Huang Haiwen , Wang Qiangli , Xu Ting , Chen Xiaochen , Jin Zhengming , Depei Wu 
Published: October 2019

Abstract
Purpose
We present the result of a comparison study between conventional chemotherapy and HCT for Peripheral T-cell lymphomas (PTCLs) in our center, especially the comparison between allo-HCT and auto-HCT.
Patients and Methods
From July 2007 to July 2014, 112 cases were analyzed retrospectively. All 112 patients were high risk group (IPI®3-4), 52 patients received conventional chemotherapy alone and 60 patients underwent HCT. In HCT group, Twenty-one (36.5%) patients received allo-HCT and thirty-nine patients (63.5%) received auto-HCT. Before receiving transplantation, 40 patients were in complete remission (CR), 2 patients were in partial remission (PR) and 18 patients were in refractory or relapse (NR). In the 18 NR patients, 11 patients accepted allo-HCT and 7 patients accepted auto-HCT. Patients¡¯ baseline characteristics were listed in Table 1 and Table 2.
Results
In this study, the longest follow-up time was 76 months and the shortest follow-up time was only two months. After chemotherapy, 31/52 patients achieved complete remission (CR)£¬5/52 patients achieved PR and 16/52 patients were not remission£¡§NR). The overall response rate was 69.2%. However, 14 patients suffered relapse in 36 responding patients, the recurrence rate was close to 50%. In allo-HCT group, 19/21 patients achieved CR and 2/21 patients died of severe infection within 100 days after HCT. In auto-HCT patients, 35/39 patients achieved CR and 4/39 patients were in NR. 7 patients experienced relapse after auto-HCT.
After a median follow-up of 33.5 months, the K-M analysis showed that the 5-year PFS for HCT and chemotherapy were 60% and 30% (p =0.006), the 5-year OS were 65% and 33% (p =0.007). The difference between the two groups was significant The 5-year PFS for auto-HCT and allo-HCT were 61% and 60% (p=0.724). The 5-year OS were 62% and 61% (p=0.724). In transplant group, the 5-year OS for patients who were CR or NR before transplantation were 81% and 53% (p=0.303). The one-year cumulative TRM of allo-HCT and auto-HCT were 22.5% and 7.8% (p=0.250). For patients whose ages are below 50, the 2-year PFS for HCT and chemotherapy were 62.7% and 34.8% (p=0.017), the 3-year OS were 71.2% and 36.7% (p=0.033). The one-year TRM of HCT and chemotherapy were 15.5% and 12.4% (p=0.203). For patients more than 50 years old, the 1-year OS for HCT and chemotherapy were 85.7% and 66.5% (p=0.384). And the one-year TRM of HCT and chemotherapy were 28.6% and 33.3% (p=0.352).
Conclusion
The majorities of PTCL patients are at high risk and have a high recurrence rate after conventional chemotherapy alone. Our results suggest that HCT is superior to conventional chemotherapy in long-term survival for PTCLs and HCT is feasible for high-risk patients with low TRM, especially in the young patients. Therefore, HCT should be considered to be the first-line therapy in high risk PTCL patients. As to PFS and OS, there seems to be no difference between auto-HCT and allo-HCT. While before transplantation, there are more NR and relapsed patients in allo-HCT group, we recommend allo-HCT for refractory and relapsed patients.
Table 1. Patient characteristics Parameters Chemotherapy HCT p value Number 52 60 Gender(female/male) 16/36 16/44 0.521 Median Age 45 29 0.003 Histological subtypes N PTCL-NOS 9 17 ALK-negative ALCL 15 15 AITL 15 17 NK/T 13 11 High risk factors B-symptoms 27 25 0.436 IPI score ®3 52 60 1.000 Ann Arbor III-IV stage 40 40 0.376 Evaluated LDH 40 42 0.546 Response to chemotherapy N CR 31 40 PR 5 2 NR 16 18 Responses to transplantation N N CR 54 PR 0 NR 4 Uncertain 2
Table 2. Patient characteristics of transplantation group Parameters Auto-HCT Allo-HCT Number 39 21 Histological subtypes PTCL-NOS 12 4 ALK-negative ALCL 13 4 AITL 7 9 NK/T 7 4 Conditioning regimen BEAM 39 0 BUCY 0 11 TBI+BUCY 0 10 Donor source N Matched unrelated donor 8 Matched sibling donor 4 Haploid donor 8 Cord blood 1 Disease status before HCT CR 30 10 PR 2 0 NR 7 11 Disease status after HCT CR 35 19 PR 0 0 NR 4 0 uncertain 0 2

Disclosures
No relevant conflicts of interest to declare.