Characteristics and Outcomes of Lung Cancer Screening Among Individuals With or Without Cancer History

Epidemiologic studies indicate that smokers with cancer history have a higher risk of developing lung cancer than smokers without cancer history. We analyzed prospectively collected data from our institutional lung cancer screening program. Comparing between the 2 groups, those with cancer history actually had a significantly lower rate of abnormal screening results than their counterparts. Background: Lung cancer screening with low-dose computed tomography (LDCT) can reduce mortality from lung cancer. Individuals with previous malignancy are at an increased risk of lung cancer but are often underrepresented in clinical trials. This study compares the outcomes of LDCT screening among individuals with and without cancer history. Materials and Methods: The study cohort included consecutive participants undergoing LDCT screening at a tertiary care cancer institution. Abnormal screening result was defined as having Lung-RADS 3 or 4 at baseline (T0). Participant information was prospectively collected and predicted risk of lung cancer was calculated per the PLCOm2012 model. Results: A total of 454 participants underwent LDCT screening. Abnormal screening result occurred in 57 (13.2%) participants at T0, and lung cancer was diagnosed in 11 (2.4%) participants. Among 153 individuals with cancer history, abnormal result occurred in 9.8%, compared with 15.4% among those without cancer history (P = .11). Lung cancer was diagnosed in 1.3%, compared with 3.5% (P = .22). The predicted risk of lung cancer at 6 years was higher among individuals with cancer history than those without: 4.8% versus 2.2% (P < .001). In a multivariable analysis, cancer history significantly reduced the likelihood of abnormal screening (odds ratio, 0.49; 95% confidence interval, 0.26-0.94; P = .03). We observed a higher proportion of participants who had a previous CT scan available for comparison at T0 among individuals with cancer history than those without: 43.1% versus 9.1% (P < .001). Conclusions: In this single-institutional study, individuals with cancer history were significantly less likely to have abnormal screening results than those without cancer history.