Background: There are well-documented disparities in lung cancer outcomes across populations. Lung cancer screening (LCS) has the potential to reduce lung cancer mortality, but for this benefit to be realized by all high-risk groups, there must be careful attention to ensuring equitable access to this lifesaving preventive health measure. Objectives: To outline current knowledge on disparities in eligibility criteria for, access to, and implementation of LCS, and to develop an official American Thoracic Society statement to propose strategies to optimize current screening guidelines and resource allocation for equitable LCS implementation and dissemination. Methods: A multidisciplinary panel with expertise in LCS, implementation science, primary care, pulmonology, health behavior, smoking cessation, epidemiology, and disparities research was convened. Participants reviewed available literature on historical disparities in cancer screening and emerging evidence of disparities in LCS. Results: Existing LCS guidelines do not consider racial, ethnic, socioeconomic, and sex-based differences in smoking behaviors or lung cancer risk. Multiple barriers, including access to screening and cost, further contribute to the inequities in implementation and dissemination of LCS. Conclusions: This statement identifies the impact of LCS eligibility criteria on vulnerable populations who are at increased risk of lung cancer but do not meet eligibility criteria for screening, as well as multiple barriers that contribute to disparities in LCS implementation. Strategies to improve the selection and dissemination of LCS in vulnerable groups are described.

Vulnerable patients find lung cancer screening decision aids helpful and generally show increased knowledge after reviewing decision aids, particularly of harms. Our results can inform future implementation efforts.

Providers endorsed the benefits of lung cancer screening, but there are limitations in provider knowledge of key screening components. The most frequently reported barriers to screening represent a lack of clinical time or resources to address lung cancer screening in clinical practice. Facilitators for nodule management as well as point-of-care referral materials may be helpful in reducing knowledge gaps and the clinical burden of referral. These are all modifiable factors, which could be addressed to increase screening referral. Differences in attitudes and barriers by specialty should also be considered to optimize screening implementation.

ObjectivesThe prevalence of emphysema is higher among HIV-infected (HIV+) individuals compared to HIV-uninfected persons. While greater tobacco use contributes, HIV-related effects on immunity likely confer additional risk. Low peripheral blood CD4+ to CD8+ T-lymphocyte (CD4/CD8) ratio may reflect chronic inflammation in HIV and may be a marker of chronic lung disease in this population. Therefore, we sought to determine whether the CD4/CD8 ratio was associated with chronic obstructive pulmonary disease (COPD), particularly the emphysema subtype, in a cohort of HIV+ subjects.MethodsWe performed a cross-sectional analysis of 190 HIV+ subjects enrolled in the Examinations of HIV Associated Lung Emphysema (EXHALE) study. Subjects underwent baseline laboratory assessments, pulmonary function testing and chest computed tomography (CT) analyzed for emphysema severity and distribution. We determined the association between CD4/CD8 ratio and emphysema, and the association between CD4/CD8 ratio and pulmonary function markers of COPD.ResultsMild or greater emphysema (>10% lung involvement) was present in 31% of subjects. Low CD4/CD8 ratio was associated with >10% emphysema in multivariable models, adjusting for risk factors including smoking, current and nadir CD4 count and HIV RNA level. Those with CD4/CD8 ratio <0.4 had 6.3 (1.1–39) times the odds of >10% emphysema compared to those with a ratio >1.0 in fully adjusted models. A low CD4/CD8 ratio was also associated with reduced diffusion capacity (DLCO).ConclusionsA low CD4/CD8 ratio was associated with emphysema and low DLCO in HIV+ subjects, independent of other risk factors and clinical markers of HIV. The CD4/CD8 ratio may be a useful, clinically available, marker for risk of emphysema in HIV+ subjects in the antiretroviral therapy (ART) era.

Lung transplant recipients have an increased risk of lung cancer that is poorly understood. Prior studies are largely descriptive and single‐center, and have not examined risk factors or outcomes in this population. This registry‐linkage study utilized matched transplant and cancer registry data from 17 US states/regions during 1987‐2012. We used standardized incidence ratios (SIRs) to compare incidence with the general population, Poisson models to identify lung cancer risk factors, and Cox models to compare survival after diagnosis. Lung cancer risk was increased among lung recipients (SIR 4.8, 95% confidence interval [CI] 4.1‐5.5). Those with single lung transplant had 13‐fold (95% CI 11‐15) increased risk in the native lung. Native lung cancer risk factors included age, prior smoking, time since transplant, and idiopathic pulmonary fibrosis. Compared with cases in the general population, lung cancers in recipients were more frequently localized stage (P = .02) and treated surgically (P = .05). However, recipients had higher all‐cause (adjusted hazard ratio 1.90, 95% CI 1.52‐2.37) and cancer‐specific mortality (adjusted hazard ratio 1.67, 95% CI 1.28‐2.18). In conclusion, lung cancer risk is increased after lung transplant, especially in the native lung of single lung recipients. Traditional risk factors are associated with lung cancer in these patients. Lung cancer survival is worse among lung recipients despite earlier diagnosis.

Background Emphysema is more prevalent in HIV-infected (HIV+) patients independent of smoking behavior. Nonetheless, health effects of emphysema in this population are poorly understood. We determined whether emphysema is associated with a greater burden of pulmonary symptoms and a lower six-minute walk distance (6MWD) in HIV+ compared to HIV-uninfected (HIV−) subjects. Methods We performed a cross-sectional analysis of 170 HIV+ and 153 HIV− subjects in the Examinations of HIV Associated Lung Emphysema (EXHALE) cohort study. Subjects completed a self-assessment of respiratory symptoms, pulmonary function testing, and 6MWD testing as well as a CT scan to determine emphysema severity. We used regression models to determine the association of emphysema with respiratory symptoms and 6MWD in HIV+ subjects and compared this to HIV− subjects. Results Models stratified by HIV status demonstrated an association between >10% radiographic emphysema and chronic cough and/or phlegm and 6MWD in HIV+ subjects. These associations persisted among the subset without airflow obstruction: those with emphysema had 4.2 (95% CI 1.3, 14) times the odds of chronic cough and/or phlegm and walked 60m (95% CI 26, 93) less distance than those without emphysema. There was no association between >10% emphysema and symptoms or 6MWD in HIV− subjects. Conclusions In our cohort, >10% radiographic emphysema was associated with chronic cough and phlegm and lower 6MWD in HIV+ but not HIV− subjects. These findings were robust even amongst HIV+ subjects with milder forms of emphysema and those without airflow obstruction, highlighting the clinical impact of emphysema in these patients.

Sclerostin domain containing 1 (SOSTDC1) protein regulates processes from development to cancer by modulating activity of bone morphogenetic protein (BMP) and wingless/int (Wnt) signaling pathways. As dysregulation of both BMP and Wnt signaling has been observed in breast cancer, we investigated whether disruption of SOSTDC1 signaling occurs in breast cancer. SOSTDC1 mRNA expression levels in breast tissue were examined using a dot blot. Affymetrix microarray data on SOSTDC1 levels were correlated with breast cancer patient survival using Kaplan–Meier plots. Correlations between SOSTDC1 protein levels and clinical parameters were assessed by immunohistochemistry of a breast cancer tissue microarray. SOSTDC1 secretion and BMP and Wnt signaling were investigated using immunoblotting. We found that SOSTDC1 is expressed in normal breast tissue and this expression is reduced in breast cancer. High levels of SOSTDC1 mRNA correlated with increased patient survival; conversely, SOSTDC1 protein levels decreased as tumor size and disease stage increased. Treatment of breast cancer cells with recombinant SOSTDC1 or Wise, a SOSTDC1 orthologue, demonstrated that SOSTDC1 selectively blocks BMP-7-induced Smad phosphorylation without diminishing BMP-2 or Wnt3a-induced signaling. In conclusion, SOSTDC1 mRNA and protein are reduced in breast cancer. High SOSTDC1 mRNA levels correlate with increased distant metastasis-free survival in breast cancer patients. SOSTDC1 differentially affects Wnt3a, BMP-2, and BMP-7 signaling in breast cancer cells. These results identify SOSTDC1 as a clinically important extracellular regulator of multiple signaling pathways in breast cancer.

Objective. Aging people living with HIV (PLWH) face an increased burden of comorbidities, including chronic obstructive pulmonary disease (COPD). The impact of COPD on mortality in HIV remains unclear. We examined associations between markers of COPD and mortality among PLWH and uninfected subjects.Design. Longitudinal analysis of the Examinations of HIV-Associated Lung Emphysema (EXHALE) cohort study.Methods. EXHALE includes 196 PLWH and 165 uninfected smoking-matched subjects who underwent pulmonary function testing and CT scans to define COPD and were followed. We determined associations between markers of COPD with mortality using multivariable Cox regression models, adjusted for smoking and the VACS Index, a validated predictor of mortality in HIV.Results. Median follow-up time was 6.9 years; the mortality rate was 2.7 per 100-person-years among PLWH and 1.7 per 100-person-years among uninfected subjects (p=0.11). The VACS Index was associated with mortality in both PLWH and uninfected subjects. In multivariable models, pulmonary function and CT characteristics defining COPD were associated with mortality in PLWH: those with airflow obstruction (FEV1/FVC<0.7) had 3.1 times the risk of death (HR 3.1 [95% CI 1.4-7.1]), compared to those without; those with emphysema (>10% burden) had 2.4 times the risk of death (HR 2.4 [95% CI 1.1-5.5]) compared to those with ≤10% emphysema. In uninfected subjects, pulmonary variables were not significantly associated with mortality, which may reflect fewer deaths limiting power.Conclusions. Markers of COPD were associated with greater mortality in PWLH, independent of the VACS Index. COPD is likely an important contributor to mortality in contemporary PLWH.