(AR P3) Y-90 PET Dose verification for Liver Cancer Y-90 Radioembolization Personalized Dosimetry

Objective: To develop personalized dosimetry algorithm for liver cancer yttrium-90 (Y-90) transarterial radioembolization and quantitative dose verification post treatment. One of the major challenges is the lack of reliable methods for dose prediction and verification. We are developing patient-specific dosimetry for personalized treatment planning using fluid dynamics (CFD) simulations of the microsphere transport combined with Y-90 physics modeling. The ultimate goal is the development of a software to optimize the amount of activity and injection point for optimal tumor targeting.

Methods: We present a proof-of-concept of CFD dosimetry based on a patient’s cone-beam CT (CBCT) performed in standard-of-care planning. The hepatic artery was segmented from the CBCT to predict the microsphere transport and calculate the dose distribution with a Y-90 dose kernel. The patient, previously diagnosed with hepatocellular carcinoma with a lesion between segments 7 and 8, received two injections of Y-90 microspheres in the right hepatic lobe: one selective injection, and one lobar injection. The Y-90 distribution was imaged with positron emission tomography (PET) scan 2 hours after radioembolization, using 15-minute scans and two bed positions.

Results: The predicted microsphere distribution using flow analysis showed that the selective injection delivered 82% of the dose to the tumor. In contrast, the lobar injection delivered microspheres to segments 5,6, 7, and 8. The radioactive absorbed dose in the liver was found to be consistent with the Y-90 PET images and the radiology report (125 Gy and 137 Gy, respectively).