Prospective CT Screening for Lung Cancer in a High-Risk Population: HIV-Positive Smokers

Abstract

Background Epidemiological evidence suggests HIV-infected individuals are at increased risk of lung cancer, but no data exist since large CT screening trials routinely exclude HIV-infected participants. Methods From 2006–2013, we conducted the first lung cancer screening trial of 224 HIV-infected current/former smokers to assess the CT detection rates of lung cancer. We also used 130 HIV-infected patients with known lung cancer to determine radiographic markers of lung cancer risk using multivariate analysis. Results Median age was 48 years with 34 pack-years smoked. During 678 person-years, one lung cancer was found on incident screening. Besides this lung cancer case, eighteen deaths(8%) occurred, but none were cancer-related. There were no interim diagnoses of lung or extrapulmonary cancers. None of the pulmonary nodules detected in 48 participants at baseline were diagnosed as cancer by study end. The heterogeneity of emphysema across the entire lung as measured by CT densitometry was significantly higher in HIV-infected subjects with lung cancer than in those without (p≤0.01). On multivariate regression, increased age, higher smoking pack-years, low CD4 nadir, and increased heterogeneity of emphysema on quantitative CT imaging were all significantly associated with lung cancer. Conclusions Despite a high rate of active smoking among HIV-infected participants, only one lung cancer was detected in 678 patient-years. This was probably due to the young age of participants suggesting that CT screening of high-risk populations should strongly consider advanced age as a critical inclusion criterion. Future screening trials in urban American must also incorporate robust measures to ensure HIV patient compliance, adherence, and smoking cessation.

HIV-Associated Lung Cancer

“…In view of the high risk profile of smoking HIV-positive individuals, 2 studies tested the survival benefit using routine LDCT scans in PLWHIV. The results of the first study screening 224 heavily smoking PLWHIV did not show a clinical advantage, finding only 1 LC case per 678 person-years, which was markedly below the results of an earlier study [61]. The younger age (median 48 years) of the participants might have contributed to this outcome, but given the described younger age at LC onset in PLWHIV, this explanation seems rather unsatisfactory.…”

Lung cancer in persons with HIV

“…Two lung cancer screening clinical trials using chest CT in HIV infected smokers have been published to date[74, 75]. The first study was conducted in Baltimore between 2006 and 2013, and enrolled a cohort with significant smoking history (median 34 pack-years) but was younger than the NLST (median age 48) [74].…”

“…The first study was conducted in Baltimore between 2006 and 2013, and enrolled a cohort with significant smoking history (median 34 pack-years) but was younger than the NLST (median age 48) [74]. Baseline screen positivity (a general measure of harms associated with screening, as most positive screens are false-positives) was broadly similar to NLST (14%).…”

Cancer screening in women living with HIV infection

“…20 In total, 224 HIV-infected (current or former smokers) underwent LDCT screening to assess the computer tomography (CT) detection rate for lung cancer. 21 None of the pulmonary nodules detected in 48 participants at baseline were diagnosed as cancer by study end, and only one cancer was detected in 678 patient-years. This may have been because of the young age of the screened population.…”