This is a prospective non-blinded case series involving the acquisition of a pair production PET/CT as soon as possible after an already performed Y-90 Sirspheres treatment of hepatic malignancy. It will be performed in addition to the standard Brehmsstrahlung SPECT scan. The sequence of the two scans in each case (PET/CT vs SPECT) will be determined by availability of the scanners at the time. However, it is intended that both be acquired on the day of the Y-90 treatment.

The length of subject participation will be one year.

The measures used will be mostly qualitative in nature, and will include:

• Correlation with expected vs. achieved tumor coverage by the treatment
• Correlation between treatment distribution depicted by Brehmsstrahlung scans vs. the Internal Pair Production PET/CT scans, to.
• Detection of non-target embolization, where applicable, and qualitative comparison between the two modalities as to the conspicuity of the abnormality

Qualitative methods will be used by the analysis of the obtained PET/CT images and comparing them to the Brehmsstrahlung SPECT images as previously described.

Inclusion Criteria:

• Recipient of Selective Internal Radiation Treatment within 5 days.
• Anticipated ability to remain still for up to 40 minutes

Exclusion Criteria:

• Anticipated Inability to lie still for up to 40 minutes
• Severe claustrophobia
• Significant cardiovascular instability, or instability of other medical/surgical conditions, such that it would be deemed unsafe or technically not feasible to obtain a PET/CT, as determined by the any member of the investigative team
• Failed deployment of the planned Y-90 treatment for any reason
• Duration of time longer than 5 days since administration of the Y-90 treatment
• Age <18
• Known pregnancy

The initial number of patients that participated in the study is 9. However, one patient elected not to return for the PET/CT scan after Y-90 delivery, therefore the total number of participants analyzed is 8 patients.