Statin Use, Heart Radiation Dose, and Survival in Locally Advanced Lung Cancer

Purpose: Patients with locally advanced non-small cell lung cancer (LA-NSCLC) have a high prevalence of pre-existing coronary heart disease and face excess cardiac risk after thoracic radiation therapy. We sought to assess whether statin therapy is a predictor of overall survival (OS) after thoracic radiation therapy. Methods and Materials: We performed a retrospective analysis of 748 patients with LA-NSCLC treated with thoracic radiation therapy, using Kaplan-Meier OS estimates and Cox regression. Results: Statin use among high cardiac risk patients (Framingham risk >= 20% or pre-existing coronary heart disease; n = 496) was 51.2%. After adjustment for baseline cardiac risk and other prognostic factors, statin therapy was associated with a significantly increased risk of all-cause mortality (adjusted hazard ratio, 1.39; 95% confidence interval [CI], 1.00-1.91; P = .048) but not major adverse cardiac events (adjusted hazard ratio, 1.18; 95% CI, 0.52-2.68; P = .69). Among statin-naive patients, mean heart dose >= 10 Gy versus <10 Gy was associated with a significantly increased risk of all-cause mortality (hazard ratio, 1.32; 95% CI, 1.04-1.68; P = .022), with 2-year OS estimates of 46.9% versus 60.0%, respectively. However, OS did not differ by heart dose among patients on statin therapy (hazard ratio, 1.00; 95% CI, 0.76-1.32; P = 1.00; P-interaction = .031), with 2-year OS estimates of 46.9% versus 50.3%, respectively. Conclusions: Among patients with LA-NSCLC, only half of statin-eligible high cardiac risk patients were on statin therapy, reflecting the highest cardiac risk level of our cohort. Statin use was an independent predictor of all-cause mortality but not major adverse cardiac events. Elevated mean heart dose (>= 10 Gy) was associated with increased risk of all-cause mortality in statin-naive patients but not among those on statin therapy, identifying a group of patients in which early intervention with statins may mitigate the deleterious effects of high heart radiation therapy dose. This warrants evaluation in prospective trials. (C) 2021 The Authors. Published by Elsevier Inc. on behalf of American Society for Radiation Oncology.

Automated summary

This study aimed to assess whether statin therapy is a predictor of overall survival in patients with locally advanced non-small cell lung cancer after thoracic radiation therapy. The results showed that statin use was associated with an increased risk of all-cause mortality but not major adverse cardiac events in these patients.