HIV-infected persons have a two-fold to five-fold increased unadjusted risk of lung cancer. In the National Lung Screening Trial (NLST), computed tomography (CT) screening was associated with a reduction in lung cancer mortality among high-risk smokers. These results may not generalize to HIV-infected persons, particularly if they are more likely to have false-positive chest CT findings.
We utilized data including standardized chest CT scans from 160 HIV infected and 139 uninfected Veterans enrolled between 2009 and 2012 in the multicenter Examinations of HIV Associated Lung Emphysema (EXHALE) Study. Abnormal CT findings were abstracted from clinical interpretations of the scans and classified as positive by NLST criteria vs. other findings. Clinical evaluations and diagnoses that ensued were abstracted from the medical record.
There was no significant difference by HIV in the proportion of CT scans classified as positive by NLST criteria (29% of HIV infected and 24% of HIV uninfected, P = 0.3). However, HIV-infected participants with CD4+ cell counts less than 200 cells/μl had significantly higher odds of positive scans, a finding that persisted in multivariable analysis. Evaluations triggered by abnormal CT scans were also similar in HIV-infected and uninfected participants (all P > 0.05).
HIV status was not associated with an increased risk of abnormal findings on CT or increased rates of follow-up testing in clinically stable outpatients with CD4+ cell count more than 200. These data reflect favorably on the balance of benefits and harms associated with lung cancer screening for HIV-infected smokers with less severe immunodeficiency.