Glass or Resin: The Ends Justify the Means?

Currently, one of the hottest topics in Yttrium-90 radioembolization is how to optimize particle number and specific activity to maximize therapeutic effects. In this context, glass microspheres and resin microspheres are at opposite ends of the spectrum [1]. Should we use glass microspheres to deliver high specific activity with minimal embolic effect, or should we use resin microspheres to enhance tumor coverage and promote homogeneous particle uptake within the tumor? Finding a sweet spot that leverages the advantages of both for different tumor types is a field ripe for further research. In this regard, the study by Kim et al. [2], analyzing around 200 patients and reporting on the treatment outcomes of glass-based and resin-based radioembolization for hepatocellular carcinoma (HCC), is noteworthy. The dosimetry approach differed between the two groups. For glass-based radioembolization, the MIRD method was used, delivering higher specific activity (mean, 3.91 GBq), while for resin-based radioembolization, the partition model was used, delivering relatively lower specific activity (mean, 2.4 GBq). Despite the heterogeneity of the patient population, the different dosimetry approaches for each group, and the lengthy 10-year patient inclusion period given the rapid advancements in radioembolization dosimetry, the nearly equivalent treatment outcomes between the two groups suggest that appropriate use of each device can yield similar results. …