This medication is different from the conventional MIBG, as it is produced by a much more refined process through a resin called Ultratrace.34 As a result, all molecules in the HSA-I-131-MIBG solution are radioactive, and the dose of radiation delivered to the tumor per dose is much higher than that of conventional MIBG (92.5 vs 1.59 MBq/μg).25 The latter is now referred to as low specific activity (LSA) I-131-MIBG.25 HSA-I-131-MIBG was only available in the United States. Here, ALB is linked to neoplasm.