Missed and Interval Lung Cancers in an Academic Lung Cancer Screening Program

To analyze imaging features and pathology of missed and interval lung cancers within an academic lung cancer screening (LCS) program.

This retrospective study included patients who underwent LCS CT in our health care network between January 2015 and June 2023 and were diagnosed with lung cancer within one year. The most recent prior LCS CT was classified as "false negative" (Lung-RADS 1 to 2) or "true positive" (Lung-RADS 3 to 4). Cancer stage and pathology were compared between false-negative and true-positive groups in the lung cancer screening program. False-negative cases were retrospectively reviewed.

A total of 456 patients were diagnosed with lung cancer. Of these, 432 (95%) were true positive, while 24 (5%) were false negative. Of the 24 false-negative studies, 8 (33.3%) were missed lung cancers, 3 (12.5%) were interval cancers (ie, no nodule visible in retrospect), and 13 (54.2%) were slow-growing ground-glass or part-solid or cystic nodules categorized as Lung-RADS 2. Missed lung cancer locations were: paramediastinal (37.5%, 3/8), perihilar (12.5%, 1/8), and endobronchial (50%, 4/8). There was no statistically significant difference in cancer histology or stage between false-negative and true-positive cases.

Within an academic lung cancer screening program, sensitivity for lung cancer detection was 95%, yet missed and interval lung cancers still occur. Endobronchial lesions are one of the more important sources of misses that are potentially addressable by radiologists.

The findings of the present study provide insight into missed and interval lung cancers within a lung cancer screening program.