Integrating coronary artery calcium scoring into radiotherapy planning CT scans to guide cardio-oncology referral in cancer patients: a multicentre prospective feasibility study

As cancer survival rates improve, focus has moved toward managing long-term treatment-related toxicities such as cardiovascular disease (CVD). Radiation is an important modality of treatment for many cancers; however, its use can lead to cardiovascular disease by accelerating the formation of coronary artery atherosclerosis. Coronary artery calcium (CAC) scoring from computed tomography (CT) scans offer a non-invasive method to assess CVD risk. Cancer patients undergoing thoracic radiotherapy require a CT scan of the chest for planning purposes. The primary aim of this study was to assess the feasibility of using radiotherapy planning CT scans to calculate CAC scores in cancer patients and establish a cardio-oncology referral pathway. Secondary aims were to evaluate the impact of CAC scoring on anxiety and quality of life (QoL); and assess adherence to cardio-oncology referral pathway. A multicentre, prospective observational study recruited 101 eligible cancer survivors (predominantly women with breast cancer) undergoing thoracic radiotherapy. CAC scores were calculated from planning CT scans, and participants with CAC > 0 were referred to cardio-oncology. QoL and anxiety were measured at baseline, shortly after CAC disclosure, and three months post-radiotherapy. Adherence to cardio-oncology referrals was recorded. CAC scores were successfully calculated for all participants; 31% had a CAC score > 0. Of those, 87% were referred to cardio-oncology and 96% of referred participants attended their appointments. Survivors with CAC > 0 had lower QoL at all timepoints, but disclosure of CAC scores did not significantly affect anxiety or QoL over time. Anxiety decreased post-disclosure in both groups. CAC scoring from radiotherapy planning CT scans is a feasible method to identify cancer survivors at elevated CVD risk. High adherence to follow-up and stable anxiety and QoL outcomes support its integration into routine cancer care. Future studies are needed to determine whether early cardiac intervention improves long-term outcomes. Ethics approval was granted by St Vincent’s Hospital (Sydney) Human Research Ethics Committee (HREC) (Project number 2021/ ETH11847). Regulatory review approval was granted by GenesisCare, and governance approval was granted by the Edith Cowan University HREC (202203326DALLAVIA). Governance approval was granted by GenesisCare and the trial was registered with Australian New Zealand Clinical Trials Registry (registration number ACTRN12621001343897p), registration date 7th October 2021.