Radio-opaque Contrast Agents for Liver Cancer Targeting With KIM During Radiation Therapy

* Sites will collect image files from the Cancer Radiation Therapy Systems and the medical records of eligible participants. For patient who do not have implanted markers, research personnel (a radiation oncologist, medical physicist or radiation therapist) will manually outline the visible contrast mass. This outline is considered the 'ground truth' of the location of the contrast mass. To ensure its accuracy, the ground truth contrast mass location will be checked by research personnel from another study site. * Image and ground truth data collected from 80% of participants will be used by University of Sydney researchers to develop the KIM algorithm to detect and track the radio-opaque contrast agents with sufficient robustness to provide justification for the prospective use of KIM as a real-time image guided radiation therapy tool for liver cancer patients. * The developed KIM software will be applied by site Medical Physicist(s) to the treatment imaging data from the remaining 20% of participants the images. Tumour positions produced by KIM will be compared with a 'ground truth' manual delineation.