Lung Cancer Screening Program Shifts the Stage of Lung Cancer at Diagnosis in Veterans

All veterans who were diagnosed with lung cancer after 3 years of participating in a screening program were found to be in stage I or II, according to a recent study that “illustrates that lung cancer screening shifts the stage of lung cancer at diagnosis.”

Dane Stewart, MD, of the University of Kansas Medical Center, and colleagues presented the study at the American Thoracic Society 2024 International Conference.

It was critical to offer the screening program because lung cancer, which “remains the leading cause of cancer-related death in the United States,” is estimated to cause the death of 15 military veterans each day, and “the majority of military veterans with lung cancer are diagnosed at stage III or IV,” Dr. Stewart and colleagues explained.

The National Lung Screening Trial showed that the implementation of low-dose computed tomography (CT) screening reduced lung cancer mortality by 20%, and in 2013, the US Preventive Services Task Force released lung cancer screening guidelines.

“Since the implementation of these recommendations, multiple studies have shown a decrease in stage at diagnosis, also known as stage shift, and overall mortality from lung cancer has decreased,” Dr. Stewart and colleagues explained.

However, these studies have not been conducted in populations of veterans, who are known to “have higher rates of lung cancer and additional occupational exposures,” according to the researchers. In addition, the Veterans Health Administration is currently implementing lung cancer screening on nationwide level.

Dr. Stewart and colleagues assessed if implementation of lung cancer screening for veterans resulted in a stage shift at time of lung cancer diagnosis. They conducted a retrospective analysis of patients enrolled in the Kansas City Veterans Administration Medical Center (KCVA) lung cancer screening program by extracting data from the automated National Data Warehouse and the KCVA lung cancer screening manual list. The lung cancer screening medical director and program director reconciled the 2 lists and at least 2 reviewers manually reviewed data from each patient.

The data abstracted included the stage at lung cancer diagnosis and the years in the screening program, with year 0 defined as the initial low-dose CT scan. The study excluded patients without staging or without tissue diagnosis.

At year 0 of screening, 72% of patients who had lung cancer were found to be in stages I or II, as opposed to stages III or IV. However, by year 2 of screening, the proportion increased to 86% of patients with lung cancer who were found to be in stage I or II. All patients diagnosed with lung cancer who reached 3 years in the screening program were found to be in stage I or II.

“Our data demonstrate that time spent in screening is associated with stage shift at diagnosis,” Dr. Stewart and colleagues concluded. “Veterans have higher rates of lung cancer than civilian populations and [lung cancer screening] is crucial in reducing mortality in this population. This study illustrates that lung cancer screening shifts the stage of lung cancer at diagnosis, which will lead to improved survival and cure from lung cancer.”

Reference

Stewart D, Evans S, and Covey A. Stage shift in military veterans enrolled in lung cancer screening programs. Presented at the American Thoracic Society 2024 International Conference; May 17-22, 2024; San Diego, California.