FDG PET for Assessment of Autologous Stem Cell Transplantation

The appropriate selection of patients to undergo hematopoietic stem cell transplant (HSCT) is critical due to the risk of treatment-related morbidity and mortality. The prognostic value of FDG-PET/CT in response assessment in hematologic malignancies is well-established and has led to numerous investigations into the role of FDG-PET/CT in the evaluation of patients in the setting of HSCT. This article discusses the most common indications for autologous stem cell transplant (autoSCT) in which FDG-PET/CT has been evaluated, including for lymphoma and multiple myeloma. For relapsed/refractory Hodgkin lymphoma, achieving a negative FDG-PET/CT scan, regardless of the number of the regimens, prior to autoSCT is an important prognostic factor for posttransplant outcome. The data in the pretransplant setting are more variable for non-Hodgkin lymphoma. For both Hodgkin and non-Hodgkin lymphoma, studies have primarily used a visual assessment for FDG-PET/CT interpretation, with the Deauville score the current standard criteria. Optimization of thresholds for specific regimens pretransplant as well as integration of additional semiquantitative parameters to assess response remain active areas of research. For multiple myeloma, FDG-PET/CT has emerged as the recommended imaging modality of choice for assessing response to treatment. Data suggest that FDG-PET/CT may provide prognostic and predictive value for assessing outcome after autoSCT.