Coronary artery calcification in thoracic cancer radiotherapy: A scoping review.

Coronary artery calcification (CAC) on computed tomography (CT) is a well-established marker of atherosclerosis, but its role in risk stratification for radiation-induced cardiovascular toxicity (RICT) remains unclear. This scoping review evaluates the current evidence on CAC in patients undergoing thoracic cancer radiotherapy (RT) and identifies key knowledge gaps. A systematic search of six databases was conducted up to December 2025, addressing six CAC-related domains: baseline prevalence, assessment methods, prognostic value for clinical outcomes, progression following RT, guideline or consensus recommendations, and clinical practice. Of the 5167 records identified, 82 studies and 15 guidelines or consensus documents met the inclusion criteria. The reported median baseline prevalence of CAC was 26 %, 66 %, and 71 % among patients with breast, esophageal, and lung cancers, respectively. CAC assessment methods varied considerably, with the Agatston score from planning CT most commonly used. Evidence supporting the prognostic value of CAC for cardiovascular outcomes was strongest in breast cancer patients receiving adjuvant RT, whereas findings in lung and esophageal cancers were inconsistent. Data on CAC progression after RT was heterogeneous, with approximately half of the studies reporting significant progression. Although several cardio-oncology societies endorse CAC-based cardiovascular risk stratification in cancer patients, it has not yet been formally adopted by RT specialty societies, and its integration into routine oncologic practice remains limited. Overall, CAC is a promising biomarker for RICT risk stratification, particularly in breast cancer patients; however, methodological variability, inconsistent findings, and limited clinical adoption highlight important knowledge gaps requiring further investigation.