Patients with double-hit lymphomas (DHLs) and double-expressor lymphomas (DELs) have inferior outcomes after undergoing autologous stem cell transplantation (ASCT), according to a new study published in the Journal of Clinical Oncology.
The worst outcomes were observed in patients with concurrent DELs and DHLs, and this “supports the concept that the double-hit/double-expressor biology appears to render DLBCL resistant to and less likely to be cured by chemotherapy,” write Alex Herrera, MD, an oncologist at the City of Hope, Duarte, Calif., and his colleagues.
But that said, a significant proportion of patients with relapsed/refractory DEL did experience durable remissions following ASCT, particularly those with isolated DEL without DHL.
This suggests that “the presence of DEL alone should not be considered a contraindication to ASCT,” the authors wrote (J Clin Oncol. 2016 Oct. 24. doi: 10.1200/JCO.2016.68.2740).
DHLs and DELs are subtypes of diffuse large B-cell lymphoma (DLBCL), and while they are associated with poor outcomes after standard chemoimmunotherapy, data remain limited as to outcomes of patients with relapsed or refractory disease who undergo ASCT.
The retrospective multicenter study included 117 patients with chemotherapy-sensitive relapsed/refractory DLBCL who underwent ASCT and had archival tumor material available. DEL with MYC/BCL2 coexpression was observed in 52 patients (44%) while 15 patients expressed MYC-R (13%), of whom 12 (10%) had DHL.
The median follow-up time was 45 months for survivors, and the 4-year progression-free survival (PFS) and overall survival (OS) were 54% for the entire cohort.
The 4-year PFS and OS in patients with DHL was worse as compared to those without DHL; 28% vs. 57% (P = .013), and 25% vs. 66% (P less than .001), respectively.
Those with DHL had poorer PFS (28%) and OS (25%), compared with patients with DEL but not DHL (PFS, 53% and OS, 61%) as well as patients with neither DEL nor DHL (PFS, 60% and OS, 70%; three-way P value for PFS, P = .013; OS, P = .002).
Patients with concurrent DEL and DHL had the poorest outcome, with a 4-year PFS of 0%.
After researchers adjusted for clinical characteristics, the only factors that remained significantly associated with PFS were DEL (hazard ratio, 1.8; P = .035) and DHL (HR, 2.9; P = .009). Factors that were significantly associated with OS were DHL (HR, 3.4; P = .004) and remission status at ASCT (HR for partial response, 2.4; P = .007).
Overall, patients with DHL were less likely to achieve a complete response following salvage therapy, and those with DEL and patients with DHL had a shorter time to relapse after induction therapy.
“Although some patients with relapsed/refractory DHL had long-term remission after ASCT (isolated DHL without DEL), the low survival rate in this group argues that alternative transplantation strategies, including allogeneic hematopoietic stem cell transplantation or peri-ASCT relapse prevention strategies should be studied,” they concluded.