Autologous stem cell transplantation for relapsed/refractory diffuse large B-cell lymphoma: efficacy in the rituximab era and comparison to first allogeneic transplants. A report from the EBMT Lymphoma Working Party.

In the era of chemoimmunotherapy, the optimal treatment paradigm for relapsed and refractory diffuse large B-cell lymphoma has been challenged. We reviewed the outcome of standard salvage therapy with an autologous stem cell transplant (autoSCT) over the last two decades and the outcome of allogeneic SCT (alloSCT) in the most recent decade. AutoSCT recipients diagnosed between 1992 and 2002 (n=2737) were compared with those diagnosed between 2002 and 2010 (n=3980). Patients diagnosed after 2002 had a significantly lower non-relapse mortality (NRM) and relapse incidence (RI) and a superior PFS and overall survival (OS). A total of 4210 patients diagnosed between 2002 and 2010 underwent either an autoSCT or an alloSCT as their first transplant procedure. Two-hundred and thirty patients received an alloSCT (myeloablative (MACalloSCT) n=132, reduced intensity (RICalloSCT) n=98). The 4-year NRM rates were 7%, 20% and 27% for autoSCT, RICalloSCT and MACalloSCT, respectively. The 4-year RI was 45%, 40% and 38% for autoSCT, RICalloSCT and MACalloSCT, respectively (NS). The 4-year PFS were 48%, 52% and 35% for autoSCT, RICalloSCT and MACalloSCT, respectively. The 4-year OS was 60%, 52% and 38% for autoSCT, RIC alloSCT and MACalloSCT, respectively. After adjustment for confounding factors NRM was significantly worse for patients undergoing alloSCT whilst there was no difference in the RI.

Tracking and evaluation of dendritic cell migration by cellular magnetic resonance imaging.

Cellular magnetic resonance imaging (MRI) is a means by which cells labeled ex vivo with a contrast agent can be detected and tracked over time in vivo. This technology provides a noninvasive method with which to assess cell-based therapies in vivo. Dendritic cell (DC)-based vaccines are a promising cancer immunotherapy, but its success is highly dependent on the injected DC migrating to a secondary lymphoid organ such as a nearby lymph node. There the DC can interact with T cells to elicit a tumor-specific immune response. It is important to verify DC migration in vivo using a noninvasive imaging modality, such as cellular MRI, so that important information regarding the anatomical location and persistence of the injected DC in a targeted lymph node can be provided. An understanding of DC biology is critical in ascertaining how to label DC with sufficient contrast agent to render them detectable by MRI. While iron oxide nanoparticles provide the best sensitivity for detection of DC in vivo, a clinical grade iron oxide agent is not currently available. A clinical grade (19) Fluorine-based perfluorcarbon nanoemulsion is available but is less sensitive, and its utility to detect DC migration in humans remains to be demonstrated using clinical scanners presently available. The ability to quantitatively track DC migration in vivo can provide important information as to whether different DC maturation and activation protocols result in improved DC migration efficiency which will determine the vaccine's immunogenicity and ultimately the tumor immunotherapy's outcome in humans.