Frequency of Incidental Findings and Subsequent Evaluation in Low-Dose Computed Tomographic Scans for Lung Cancer Screening

Rationale: The U.S. Preventive Services Task Force recommends lung cancer screening with low-dose chest computed tomographic scans (LDCT) for a well-defined high-risk population. Data on the frequency and impact of incidental findings (IFs) based on LDCT scans performed within a centralized lung cancer screening program have not been reported.

Objectives: Researchers in previous studies have reported IFs in the setting of clinical trials. We present our findings in a real clinical setting where the decision to manage these findings may depend on factors that are not captured in a research trial such as disclosing IFs, patient preferences, severity of comorbidities, and physician expertise.

Methods: We conducted a retrospective chart review of participants in the Cleveland Clinic Lung Cancer Screening Program from April 1, 2015, to February 17, 2016. Lung Imaging Reporting and Data System categories and all reported findings were extracted from the structured radiology report. Downstream investigations that occurred as a result of the imaging findings were recorded. Medicare reimbursement rates were documented for all screening-related testing and treatment.

Results: A total of 320 LDCT-screened patients' records were reviewed. The most commonly reported IFs were pulmonary (69.6%), cardiovascular (67.5%), and gastrointestinal (25.9%). Fifteen percent of the scans had an IF that resulted in further evaluation. The majority of patients who underwent further testing had cardiovascular findings (10.3%); less frequently, they had thyroid or adrenal nodules (2.1%), hepatic lesions (0.9%), renal masses (0.6%), or pulmonary disease (0.6%). The most frequently ordered investigations were echocardiography (n = 9), cardiac stress test (n = 9), and CT angiography (n = 6). Reimbursement for the screening process, evaluation, and treatment of screening-detected findings averaged $817 per screened patient.

Conclusions: Clinically significant IFs on LDCT scans for lung cancer screening are common, and their potential impact should be included in the shared decision-making process. Screening program staff should develop a standard approach for the evaluation of these findings and consider the financial impact when seeking infrastructure support for screening program implementation.