The Predictive Value of Preoperative Coronary Artery Calcium Score for Long-term Survival in Elderly Patients with Lung Cancer After Surgery

BACKGROUND: A large proportion of elderly lung cancer patients have coronary atherosclerosis. However, it remains unclear which coronary artery indicators provide optimal prognostic value for elderly patients with lung cancer after surgery. METHODS: This study retrospectively analyzed the clinical data of elderly patients with lung cancer who underwent surgery between September 2013 and September 2021. Three coronary artery indicators including the severity of coronary artery stenosis, coronary artery calcium score (CACS), and computed tomography-derived fractional flow reserve (CT-FFR) and clinical data were evaluated. The Cox proportional hazards model and competing risk model were used to identify independent prognostic factors for all-cause death and non-lung cancer death, respectively. Based on these factors, a nomogram was developed and validated to predict the overall survival of elderly patients with lung cancer after surgery. The performance of the nomogram was evaluated using the concordance index, receiver operating characteristic curve, calibration curve, and decision curve analysis. RESULTS: The study finally included 896 elderly patients with lung cancer, randomly divided into training group (n=627) and validation group (n=269) in a 7:3 ratio. Among the three coronary artery indicators, only CACS >40 affected the long-term survival of elderly patients with lung cancer after surgery, especially for those who underwent lobectomy, but had no effect on those undergoing sublobar resection. Age, smoking, %dynamic diffusion lung capacity of carbon monoxide (DLCO), CACS >40, surgical procedure, pathological stage, and pathological type were identified as independent prognostic factors for all-cause death. Smoking and CACS >40 were identified as independent risk factors for non-lung cancer death. The nomogram incorporating CACS exhibited robust predictive performance. CONCLUSION: This study shows that CACS has a significant predictive value for all-cause death and non-lung cancer death in elderly lung cancer patients after surgery. For elderly lung cancer patients with high CACS, sublobar resection may improve their survival compared to lobectomy.