Personalizing Veterans' Lung Cancer Screening and Diagnosis

Annual lung cancer screening with low-dose computed tomography (LDCT) is recommended by the U.S. Preventive Services Task Force (USPSTF) for individuals aged 50-80 years with a ≥20 pack-year smoking history who currently smoke or quit within the past 15 years. However, USPSTF eligibility criteria identify only an estimated 45-65% of lung cancers that are ultimately diagnosed. Veterans face an increased risk of lung cancer due to higher rates of tobacco use and additional service-related exposures, including Agent Orange, asbestos, burn pits, and ionizing radiation.

This proof-of-concept, non-inferiority prospective cohort study aims to evaluate a personalized lung cancer screening protocol tailored to the Veteran population. We will enroll 1,400 Veterans across seven VA medical centers (Nashville, Denver, Louisville, Chicago, Kansas City, Salisbury, and Seattle). Eligible participants will be 50-80 years old, have any history of cigarette smoking, and possess at least one additional lung cancer risk factor (COPD diagnosis, prior tobacco-related cancer, family history of lung cancer, or the above service-related exposures). Participants will undergo annual LDCT screening interpreted using standard-of-care Lung-RADS criteria.

The primary non-inferiority analysis will determine whether this expanded, Veteran-specific screening eligibility (experimental group) detects at least the same proportion of lung cancers as the historical cohort screened under USPSTF criteria within Lung Precision Oncology Program sites. A non-inferiority margin of 0.5% was selected based on clinical significance.

Because broader eligibility will increase the number of indeterminate pulmonary nodules, the investigators will also assess whether a combined biomarker strategy can improve diagnostic efficiency. Among 520 Nashville Veterans with positive LDCT results, the investigators will test whether pairing image-based biomarkers with blood-based biomarkers reduces invasive procedures and shortens time to diagnosis compared with the Brock Model.

We hypothesize that the Veteran-specific screening criteria will be non-inferior to USPSTF criteria in lung cancer incidence detected and that a combined biomarker approach will reduce unnecessary procedures and accelerate diagnostic timelines for Veterans with positive screening findings. This study will provide proof-of-concept evidence supporting personalized lung cancer screening for Veterans and the integration of biomarker-guided management for screen-detected indeterminate pulmonary nodules.

This study also includes a Community Advisory Board (CAB) composed of Veterans, members of Veteran organizations, and Veteran family members (n=15). The purpose of the CAB is to incorporate Veteran perspectives on study progress. The CAB will also inform dissemination of all study results to the community, including any lay written report and presentations to the community. We will conduct semi-structured interviews (n=60 or until thematic saturation is reached) with Veterans who have undergone lung cancer screening as part of expanded criteria and usual screening criteria (USPSTF). These interviews will assess Veteran preferences for lung cancer screening outreach and engagement.

Inclusion criteria

• Date of birth and sex recorded
• Active user of VA (at least 1 primary care encounter in prior 2 years) at Nashville, Denver, Louisville, Chicago Jesse Brown, Kansas City, Salisbury or Seattle VAMC
• Tobacco Use: Self-reported tobacco use of at least 100 cigarettes in lifetime
• Additional Risk Factor

• Self-reported history of military service exposure: direct contact with asbestos- containing material, agent orange, ionizing radiation or burn pit
• Chronic obstructive pulmonary disease (COPD) defined as one of the two definitions below:

1.Forced expiratory volume during the first second/forced vital capacity (FEV1/ FVC) ratio of below 70% predicted 2.FEV1/FVC greater than 70% predicted or pulmonary function test (PFT) unavailable plus respiratory symptoms (chronic cough, sputum production, shortness of breath, chest tightness, wheezing) plus any one of the following functional abnormalities on PFTs or structural abnormalities on imaging:

• Functional abnormalities on PFTs:

I.FEV1 below the lower limit of normal II.Gas trapping defined as residual volume greater than upper limit of normal III.Hyperinflation defined as two out of three lung volumes (total lung capacity, functional residual capacity, residual volume) that are greater than the upper limit of normal IV.Reduced diffusion capacity of the lungs for carbon monoxide (DLCO) defined as DLCO lower than the lower limit of normal V.Rapid FEV1 decline defined as greater than 60ml/year or greater than or equal to 15% decline in FEV1

• Structural abnormalities on imaging:

I.Emphysema II.Air trapping/mosaicism

• Self-reported prior history of tobacco-related cancer (oral cavity and pharynx, esophagus, stomach, colorectal, liver and intrahepatic bile duct, pancreas, larynx, lung and bronchus, cervix uteri, kidney and renal pelvis, urinary bladder, and acute non-lymphocytic leukemia) and without evidence of disease for at least 5 years based on chart review
• Self-reported family history of primary lung cancer in a first degree relative 5.No exclusion criteria at study screening

Exclusion criteria

• Self-reported, family-reported or electronic health record (EHR) diagnosis of dementia via chart review or failure of 3-word recall from Mini-cog during study screening
• Self-reported or EHR documented thoracic imaging surveillance for cancer or chronic lung disease
• Self-reported or EHR diagnosis of severe illness on chart review defined as:

• Hospice
• End Stage Pulmonary disease or continuous supplemental oxygen use
• Heart Failure with ejection fraction (EF) less than 25%
• Transplant of any organ or bone marrow
• Active cancer currently being treated except non-melanoma skin cancer
• Condition that precludes lung cancer screening due to limited ability to undergo treatment as deemed by study PI
• Pregnancy in the second or third trimester
• Inability to give informed consent; no minors, prisoners, or incapacitated
• Inability to complete computed tomography (CT) scan