A single center's experience using four different front line mobilization strategies in lymphoma patients planned to undergo autologous hematopoietic cell transplantation.

In an otherwise eligible patient with relapsed lymphoma, inadequate mobilization of hematopoietic stem cells (HSCs) is a limiting factor to proceeding with an autologous hematopoietic cell transplantation (auto-HCT). Multiple strategies have been used to mobilize an adequate number of HSCs with no obvious front-line strategy. We report a single institutional experience mobilizing HSCs using four different approaches in lymphoma patients. We prospectively collected mobilization outcomes on patients planned to undergo auto-HCT at Ohio State University. We report results of first mobilization attempts for all relapsed or refractory lymphoma patients between 2008 and 2014. We identified 255 lymphoma patients who underwent mobilization for planned auto-HCT. The 255 lymphoma patients underwent the following front line mobilization strategies: 95 (37%) G-CSF alone, 38 (15%) chemomobilization (G-CSF+chemotherapy), 97 (38%) preemptive day 4 plerixafor, and 25 (10%) rescue day 5 plerixafor. As expected, there were significant differences between cohorts including age, comorbidity indices, histology, and amount of prior chemotherapy. After controlling for differences between groups, the odds of collecting 2 × 106/kg HSCs on the first day of collection and 5 × 106/kg HSCs in total was the highest in the cohort undergoing chemomobilization. In conclusion, our experience highlights the effectiveness of chemomobilization.

The Epstein-Barr Virus (EBV) in T Cell and NK Cell Lymphomas: Time for a Reassessment.

While Epstein-Barr virus (EBV) was initially discovered and characterized as an oncogenic virus in B cell neoplasms, it also plays a complex and multifaceted role in T/NK cell lymphomas. In B cell lymphomas, EBV-encoded proteins have been shown to directly promote immortalization and proliferation through stimulation of the NF-κB pathway and increased expression of anti-apoptotic genes. In the context of mature T/NK lymphomas (MTNKL), with the possible exception on extranodal NK/T cell lymphoma (ENKTL), the virus likely plays a more diverse and nuanced role. EBV has been shown to shape the tumor microenvironment by promoting Th2-skewed T cell responses and by increasing the expression of the immune checkpoint ligand PD-L1. The type of cell infected, the amount of plasma EBV DNA, and the degree of viral lytic replication have all been proposed to have prognostic value in T/NK cell lymphomas. Latency patterns of EBV infection have been defined using EBV-infected B cell models and have not been definitively established in T/NK cell lymphomas. Identifying the expression profile of EBV lytic proteins could allow for individualized therapy with the use of antiviral medications. More work needs to be done to determine whether EBV-associated MTNKL have distinct biological and clinical features, which can be leveraged for risk stratification, disease monitoring, and therapeutic purposes.

An effective mobilization strategy for lymphoma patients after failed upfront mobilization with plerixafor.

In an otherwise eligible patient, inadequate mobilization of PBSCs is a limiting factor to proceeding with an auto-ASCT. In such situations, plerixafor is commonly added to improve PBSC collection yields along with cytokine (G-CSF alone) or chemomobilization (chemotherapy+G-CSF). Individually, both strategies are proven to be safe and effective. Here we report six patients who underwent successful mobilization with combination chemomobilization plus plerixafor after upfront failure of cytokine mobilization plus plerixafor. The median CD34(+) cell yield after chemomobilization was 2.48 × 10(6)/kg (range 0.99-8.49) after receiving one to two doses of plerixafor. All patients subsequently underwent ASCT without major unforeseen toxicities and engrafted successfully. No significant delays in time to neutrophil recovery were observed. Our experience highlights the safety and effectiveness of chemomobilization with plerixafor after G-CSF plus plerixafor (G+P) failure and suggests this is a viable salvage strategy after initial failed G+P mobilization.