Ethnic Disparities in Imaging Utilization at Diagnosis of Non-Small Cell Lung Cancer

Rustain L. Morgan, MD, MS; Sana D. Karam, MD, PhD; Cathy J. Bradley, PhD


J Natl Cancer Inst. 2020;112(12):1204-1212. 

In This Article

Abstract and Introduction


Background: Prior research demonstrated statistically significant racial disparities related to lung cancer treatment and outcomes. We examined differences in initial imaging and survival between blacks, Hispanics, and non-Hispanic whites.

Methods: The linked Surveillance, Epidemiology, and End Results-Medicare database between 2007 and 2015 was used to compare initial imaging modality for patients with lung cancer. Participants included 28 881 non-Hispanic whites, 3123 black, and 1907 Hispanics, patients age 66 years and older who were enrolled in Medicare fee-for-service and diagnosed with lung cancer. The primary outcome was comparison of positron emission tomography (PET) imaging with computerized tomography (CT) imaging use between groups. A secondary outcome was 12-month cancer-specific survival. Information on stage, treatment, and treatment facility was included in the analysis. Chi-square test and logistic regression were used to evaluate factors associated with imaging use. Kaplan-Meier method and Cox proportional hazards regression were used to calculate adjusted hazard ratios and survival. All statistical tests were two-sided.

Results: After adjusting for demographic, community, and facility characteristics, blacks were less likely to undergo PET or CT imaging at diagnosis compared with non-Hispanic whites odds ratio (OR) = 0.54 (95% confidence interval [CI] = 0.50 to 0.59; P < .001). Hispanics were also less likely to receive PET with CT imaging (OR = 0.72, 95% CI = 0.65 to 0.81; P < .001). PET with CT was associated with improved survival (HR = 0.61, 95% CI = 0.57 to 0.65; P < .001).

Conclusions: Blacks and Hispanics are less likely to undergo guideline-recommended PET with CT imaging at diagnosis of lung cancer, which may partially explain differences in survival. Awareness of this issue will allow for future interventions aimed at reducing this disparity.


In 2018, there were an estimated 234 030 new cases of lung cancer, with 158 770 estimated deaths.[1] Despite improvement in survival of patients with lung cancer, it remains the leading cause of cancer death.[1] Although the lung cancer survival rate for all patients remains low,[1] blacks have worse outcomes with a 5-year all-stages survival rate of 15% compared with 18% for non-Hispanic whites.[1] Both blacks and Hispanics are often advanced stage at diagnosis relative to non-Hispanic whites.[1,2] Numerous factors that contribute to lung cancer disparities, including early detection, smoking, biology, environmental, and societal factors, have been described.[3] Recent medical innovations provide new therapeutic options and are improving outcomes, but the optimization of such treatments depends on the patient's stage. Appropriate imaging is imperative for improving the accuracy of staging and optimizing the choice of therapeutic interventions.[4]

Current NCCN guidelines recommend a CT of the Chest and upper abdomen with contrast for initial evaluation of non-small cell lung cancer (NSCLC).[5] A 18F-fludeoxyglucose positron emission tomography (PET) with computerized tomography (CT) imaging is then recommended for stage I to stage IV NSCLC patients. In addition, the European Society for Medical Oncology, the Pan-Asian adapted Clinical Practice Guidelines, and the American College of Radiology Appropriateness Criteria all support a role for PET imaging in cases of newly diagnosed NSCLC.[4,6–8] The national and international level of support for PET imaging is due to numerous prior studies demonstrating both prognostic and management improvement in patients who receive a PET exam. One recent study showed PET serves as an independent prognostic factor for disease recurrence for early-stage IA NSCLC.[9] A prospective multicenter randomized trial found combining PET with conventional workup reduced futile thoracotomies by 51%.[10] A second prospective multicenter trial found PET imaging resulted in a change of management in 72% of cases.[11] Although the benefits PET offers in staging and patient management have been reported,[10,11] the inequity of its use for patients with newly diagnosed NSCLC has not been evaluated in a national Medicare population. Given the impact of PET on patient management and outcomes, this study examines differences in imaging use of blacks, Hispanics, and white patients with newly diagnosed lung cancer and the impact on patient survival.