Radiotherapy Dose Exposure Thresholds and Adverse Cardiac Events in Patients With NSCLC
Posted: Wednesday, March 10, 2021
For patients with locally advanced non–small cell lung cancer (NSCLC), the presence of preexisting coronary heart disease may impact the optimal cardiac dose constraints, according to a study published in JAMA Oncology. Patients with coronary disease and a left ventricular V15 Gray dose greater than or equal to 1% demonstrated an increased risk for major adverse cardiac events. However, the variation in identified constraints suggests additional research is necessary to identify risk-mitigation strategies, explained Katelyn M. Atkins, MD, PhD, of Dana-Farber Cancer Institute and Brigham and Women’s Hospital, Boston, and colleagues.
From 2003 to 2014, a total of 701 patients with locally advanced NSCLC were recruited for the study. All patients had received thoracic radiotherapy. The authors measured the major adverse cardiac events using operating curve and cut-point analyses and calculated the radiotherapy dose parameters.
The study findings revealed the optimal cut points for the left circumflex coronary artery V15 Gray dose greater than or equal to 14% (C-index = 0.64), left anterior descending coronary artery V15 Gray dose greater than or equal to 10% (C-index = 0.64), and left ventricle V15 Gray dose greater than or equal to 1% (C-index = 0.64). In addition, the C-index was 0.62 for the mean total coronary artery dose greater than or equal to 7 Gray. Furthermore, assessment of the major adverse cardiac events and all-cause mortality for the left anterior descending coronary artery V15 Gray dose greater than or equal to 10% revealed an increased risk for both, with hazard ratios of 13.90 and 1.58, respectively. Moreover, notable differences in major adverse cardiac events were identified for patients with and without coronary heart disease.
Disclosure: For full disclosures of the study authors, visit jamanetwork.com.
