Lack of Adherence to Guideline-Based Imaging Before Subsequent Radiation in Patients with Non–Small Cell Lung Cancer: Impact on Patient Outcomes

Abstract

Lung cancer is the leading cause of cancer death within the United States, yet prior studies have shown a lack of adherence to imaging and treatment guidelines in patients with lung cancer. This study evaluated the use of 18F-FDG PET/CT imaging before subsequent radiation therapy (RT) in patients with non–small cell lung cancer (NSCLC), as recommended by National Comprehensive Cancer Network guidelines, and whether the use of this imaging modality impacts cancer-specific survival. Methods: This was a retrospective study of the National Cancer Institute’s Surveillance, Epidemiology, and End Results program of Medicare-linked data in patients with NSCLC. Hazard ratios and 95% CIs for overall and cancer-specific survival were estimated for patients diagnosed between 2006 and 2015 who underwent either 18F-FDG PET/CT–based or CT-based imaging before subsequent RT. Results: Significant improvement in cancer-specific survival was found in patients who underwent 18F-FDG PET/CT imaging before subsequent RT, compared with those who underwent CT (hazard ratio, 1.43 [95% CI, 1.32–1.55; P, 0.0001]). Although the National Comprehensive Cancer Network recommends 18F-FDG PET/CT before subsequent RT, 43.6% of patients were imaged with CT alone. Conclusion: Many patients with NSCLC are not being imaged according to national guidelines before subsequent RT, and this omission is associated with a lower cancer-specific survival.