Use of 68 Ga-labeled Macroaggregated Albumin Particles for Selective Internal Radiation Therapy (SIRT) Dosimetry and Treatment Planning.

In October 2024, Europe again experienced a period of shortage of technetium-labeled tracers. In order not to delay time-critical treatments of liver tumors, we turned to 68 Ga-labeled macroaggregated albumin particles ([ 68 Ga]Ga-MAA) as already used for lung perfusion PET imaging for selective internal radiation therapy (SIRT) dosimetry and treatment planning. Labeling was performed under GMP conditions and could be applied for SIRT planning in one patient. Post-therapy dosimetry based on [ 90 Y]microsphere PET/CT demonstrated excellent agreement. Dosimetry and treatment planning with [ 68 Ga]Ga-MAA should be considered as a viable alternative to [ 99m Tc]Tc-MAA SPECT/CT and could be considered for routine use.