Radiation Oncology Opinions and Practice on Cardiotoxicity in Lung Cancer: A Cross-sectional Study by the International Cardio-oncology Society.

Aims: Symptomatic radiation cardiotoxicity affects up to 30% patients with lung cancer and several heart substructure doses are associated with reduced overall survival. A greater focus on minimising cardiotoxicity is now possible due to advancements in radiotherapy technology and the new discipline of cardio-oncology, but uptake of emerging data has not been ascertained. A global cross-sectional analysis of Radiation Oncologists who treat lung cancer was therefore conducted by the International Cardio-Oncology Society in order to establish the impact of recently published literature and guidelines on practice.

Materials and methods: A bespoke questionnaire was designed following an extensive review of the literature and from recurring relevant themes presented at Radiation Oncology and Cardio-Oncology research meetings. Six question domains were retained following consensus discussions among the investigators, comprising 55 multiple choice stems: guidelines, cardiovascular assessment, cardiology investigations, radiotherapy planning strategies, primary prevention prescribing and local cardio-oncology service access. An invitation was sent to all Radiation Oncologists registered with ICOS and to Radiation Oncology colleagues of the investigators.

Results: In total 118 participants were recruited and 92% were consultant physicians. The ICOS 2021 expert consensus statement was rated as the most useful position paper, followed by the joint ESC-ESTRO 2022 guideline. The majority (80%) of participants indicated that a detailed cardiovascular history was advisable. Although 69% of respondents deemed the availability of cardiac substructure auto-segmentation to be very/quite important, it was implemented by only a few, with the most common being the left anterior descending coronary artery V15. A distinct cardio-oncology service was available to 39% participants, while the remainder utilised general cardiology services.

Conclusion: The uptake of recent guidelines on cardiovascular optimisation is good, but access to cardiology investigations and consultations, and auto-segmentation, represent barriers to modifying radiotherapy practices in lung cancer to reduce the risk of radiation cardiotoxicity.