Can coronary artery calcium (CAC) score be calculated on radiotherapy planning computed tomography (CT) scans? (RO-CARDIAC)

Main Study The study is investigating whether coronary artery calcium (CAC) score can be measured on thoracic radiotherapy planning computed tomography (CT) scan. It is the first prospective study in which this will be investigated. Patients who are ineligible or choose not to enrol in the study will not have CAC scored. They will be counselled on cardiac risk by their treating doctor and if indicated referred to a cardiologist as standard processes. CAC scoring will not involve any additional procedure (including dye or tracer) or time for study participants above their standard radiotherapy planning CT which is completed as part of their normal care. Following the scan, the CT images will be provided to a central cardiologist who will measure the patient's CAC score. Following receipt of the CAC score, patients that are identified as high risk, defined as those with a CAC score of >0, will be referred to a CardioOncology clinic. When the CAC score is received, the participant's doctor will discuss the result with them and provide this referral. Following referral, participants will then be managed by the cardiologist as clinically required per normal cardiology practice. Participants will also continue with radiotherapy as per normal with their radiation oncologist. Participants with a CAC score of 0 are not considered high risk, and will therefore not be referred to the CardioOncology clinic. They will be managed by their treating radiation oncologist as per normal. Feasibility as defined by adherence to the recommended pathway and impact on patient quality of life will be observed. Participants will be asked to complete questionnaires assessing general quality of life, anxiety and patient experience at Baseline, following CAC scoring and approximately 3 months after completing their radiotherapy treatment. The research team will assess adherence to the treatment pathway by reviewing medical records for attendance at the 3 month follow-up. The duration of study participation for participants will be up to approximately 6 months, depending on the length of their radiotherapy treatment regimen Optional Sub-study (WA only) Patients who reside in WA will have the option to take part in an additional sub-study, coordinated by our colleagues at Edith Cowan University. Patients living outside of WA, or choose not to enrol in the sub-study will not have any procedures outlined in the sub-study completed. They will continue to take part in the main study. In addition to CAC measured in the coronary arteries, the abdominal aorta is another blood vessel in which calcium build up can be measured. The optional sub-study aims to measure abdominal aortic calcification (AAC) on Bone density scans (Dual-energy X-ray Absorptiometry, or DXA scans) to help identify patients who are at a higher risk of a heart attack in the future, as well as to measure bone density and body composition. Previous studies have measured AAC in the general population, but this study will be the first time AAC is being used to assess cardiovascular health in cancer patients. Risk of a future heart attack can be reduced by following dietary and physical activity guidelines. Therefore, the sub-study will also examine diet and physical activity behaviours. It will also assess the diet and physical activity support patients undergoing radiotherapy receive throughout their treatment. Patients that take part in the sub-study will have their weight and height measured, undergo four DXA scans to measure body composition and AAC, and complete two online questionnaires within 2 weeks of starting radiotherapy. These procedures are all completed specifically for the sub-study in addition to standard of care. DXA scan and AAC results will be provided to the patient’s GP who will discuss any abnormal results. Following completion of their radiotherapy, selected sub-study participants will complete an online interview with researchers to ask about their experiences receiving diet and physical activity support during treatment. All sub-study participants will complete a 12 month follow up visit after Baseline where the same study assessments will be completed again for comparison. The duration of study participation for all participants is therefore approximately 12 months.