by
Evgeny Klyuchnikov;
Ulrike Bacher;
Nicolaus M. Kroeger;
Parameswaran N. Hari;
Kwang Woo Ahn;
Jeanette Carreras;
Veronika Bachanova;
Asad Bashey;
Jonathon Cohen;
Anita D'Souza;
César O. Freytes;
Robert Peter Gale;
Siddhartha Ganguly;
Mark S. Hertzberg;
Leona A. Holmberg;
Mohamed A. Kharfan-Dabaja;
Andreas Klein;
Grace H. Ku;
Ginna G. Laport;
Hillard M. Lazarus;
Alan M. Miller;
Alberto Mussetti;
Richard F. Olsson;
Shimon Slavin;
Saad Z. Usmani;
Ravi Vij;
William A. Wood;
David G. Maloney;
Anna M. Sureda;
Sonali M. Smith;
Mehdi Hamadani
Purpose: Comparison of long-term outcomes in patients with refractory/relapsed grade 1-2 follicular lymphoma (FL) after allogeneic (allo-HCT) vs. autologous hematopoietic cell transplantation (auto-HCT) in the rituximab-era.
Methods: Adult patients with relapsed/refractory grade 1-2 FL undergoing 1st reduced-intensity allo-HCT or 1st autograft during 2000-2012 were evaluated.
Results: A total of 518 rituximab-treated patients were included. Allo-HCT patients were younger; more heavily pretreated, and more patients had advanced stage and chemoresistant disease. The 5-year adjusted probabilities, comparing auto- vs. allo-HCT groups for non-relapse mortality (NRM) were 5% vs. 26% (p<0.0001); relapse/progression: 54% vs. 20% (p<0.0001); progression-free survival (PFS): 41% vs. 58% (p<0.001) and overall survival (OS): 74% vs. 66% (p=0.05). Auto-HCT was associated with a higher risk of relapse/progression beyond 5 months post-HCT (RR=4.4; p<0.0001), and worse PFS (RR=2.9; p<0.0001) beyond 11 months post HCT. In the first 24 months post HCT, auto-HCT was associated with improved OS (RR=0.41; p<0.0001), but beyond 24 months with inferior OS (RR=2.2; p=0.006). A landmark analysis of patients alive and progression-free at 2-years post-HCT confirmed these observations, showing no difference in further NRM between both groups, but significantly higher risk of relapse/progression (RR=7.3; p<0.0001) and inferior PFS (RR=3.2; p<0.0001) and OS (RR=2.1; p=0.04) following auto-HCT. The 10-year cumulative incidence of second hematological malignancies following allo- and auto-HCT was 0% and 7%, respectively.
Conclusion: Auto- and RIC-allo-HCT as 1st transplantation approach can provide durable disease control in grade 1-2 FL patients. Continued disease relapse-risk following auto-HCT translates into improved PFS and OS following allo-HCT, in long-term survivors.