Comparison of Yttrium-90 Absorbed Doses Using PET/CT Versus PET/MR Imaging for Hepatic Malignancies

Comparison of Yttrium-90 Absorbed Doses Using PET/CT Versus PET/MR Imaging in Patients Undergoing Selective Internal Radiation Therapy for Hepatic Malignancies

The purpose of this study is to compare the results of positron emission tomography/computer tomography (PET/CT) to positron emission tomography/magnetic resonance imaging (PET/MRI) to help determine any added advantage of one over the other in relation to a tumor which might assist in further management plans.

Participants in this study will undergo PET/CT (standard imaging) and PET/MR (additional imaging), within 6 hours after SIRT with Y-90 for palliative treatment of the liver malignancy. Patients will be randomized to receive either of the imaging modalities first, based on the availability of the imaging device, and less than 1 hour apart. Upon acquirement and construction of PET/CT and PET/MR images, a software (MIM SurePlan LiverY90) would be utilized for semi-automatic determination of the liver/tumor contours and calculation of the Y-90 absorbed doses (Gy) in the regions of interest (including within tumor and background liver outlines) using the Local Deposition Method.

The primary objective of this study is to assess the agreement between post-Y-90 RE absorbed doses (Gy) in the liver tumor tissues based on PET/CT versus PET/MR imaging. This would permit the comparison of Y-90 tumor absorbed doses, acquired from PET/MR, with the current standard of care PET/CT imaging to verify the data consistency and to validate its application for the prediction of tumor response to treatment.

The secondary objective of this study is to assess the agreement between post-Y-90 RE absorbed doses (Gy) in the background liver tissues (surrounding tumors), based on PET/CT versus PET/MR imaging. This would permit the comparison of Y-90 background liver absorbed doses, acquired from PET/MR, with the current standard of care PET/CT imaging to verify the data consistency and to validate its application for the prediction of dose toxicity.

Inclusion Criteria:

• The patient has a liver malignancy and is scheduled for SIRT with Y-90; AND
• The patient is an adult, self-competent, and able to provide informed consent to participate in the study

Exclusion Criteria:

• The patient loses competence, has a condition that questions their ability to provide informed consent independently (e.g. cannot communicate in English), or withdraws consent to participate within any time in the study period; OR
• The patient is not eligible to undergo MRI due to the presence of metal devices or implants in their body; OR
• Both imaging modalities cannot take place within 6 hours after Y-90 RE; OR
• Both imaging modalities cannot take place within 1 hour apart from each other