Cumulative Incidences of Lung Cancer in Various Interstitial Lung Diseases

Background Interstitial lung disease (ILD) patients often develop lung cancer. However, previous studies on the incidences of lung cancer in ILD patients focused on specific aetiologies, such as idiopathic pulmonary fibrosis (IPF). The lung cancer incidences in these patients have not been investigated, and thus, we aimed to evaluate them here. Methods ILD patients at our hospital were retrospectively reviewed. The cumulative incidences of lung cancer in patients with various ILDs were estimated with Kaplan-Meier curves and compared between ILD groups using log-rank tests. The association between several variables at initial diagnosis and lung cancer development was assessed with Cox proportional hazards regression analysis to identify predictors. Results In all, 606 ILD patients, including 161 with IPF, 133 with non-IPF idiopathic interstitial pneumonias, 160 with chronic hypersensitivity pneumonitis, 87 with connective tissue disease-related ILDs, 19 with pulmonary sarcoidosis, and 46 with other ILDs, were included. Twenty-eight patients developed lung cancer. The cumulative incidences of lung cancer at 1, 3, and 5 years were: 1.9, 5.7, and 12.3% with IPF, respectively; 0.8, 0.8, and 4.0% in non-IPF idiopathic interstitial pneumonias; 2.0, 4.6, and 11.0% in chronic hypersensitivity pneumonitis; and 1.1, 1.1, and 2.9% in connective tissue disease-related ILDs. IPF patients had a higher incidence of lung cancer than non-IPF idiopathic interstitial pneumonia patients (p = 0.036). A radiological usual interstitial pneumonia pattern, forced vital capacity value, and pack-years were associated with lung cancer development (hazard ratios 2.959, 1.031, 1.011; 95% confidence intervals 1.257–6.963, 1.006–1.057, 1.002–1.020, p = 0.013, 0.017, 0.020, respectively). Conclusions The lung cancer incidence is higher in IPF patients than in non-IPF idiopathic interstitial pneumonia patients and is equally high in patients with chronic hypersensitivity pneumonitis and IPF.

Impact of bronchoalveolar lavage lymphocytosis on the effects of anti-inflammatory therapy in idiopathic non-specific interstitial pneumonia, idiopathic pleuroparenchymal fibroelastosis, and unclassifiable idiopathic interstitial pneumonia

Background Idiopathic non-specific interstitial pneumonia (iNSIP), idiopathic pleuroparenchymal fibroelastosis (iPPFE), and unclassifiable idiopathic interstitial pneumonia (IIP) are IIPs with chronic fibrotic phenotypes, and unlike idiopathic pulmonary fibrosis, they have often been treated with anti-inflammatory drugs, including corticosteroids and immunosuppressants. However, the impact of bronchoalveolar lavage (BAL) lymphocytosis on the effects of anti-inflammatory therapy has never been evaluated. This study aimed to elucidate whether BAL lymphocytosis can be used to predict the efficacy of anti-inflammatory drugs for iNSIP, iPPFE, and unclassifiable IIP. Methods Japanese patients diagnosed with iNSIP, iPPFE, and unclassifiable IIP by multidisciplinary discussion were identified using the nationwide registry. Eligible patients were stratified into four groups with and without BAL lymphocytosis and anti-inflammatory therapy to compare overall survival (OS) and changes in lung function. BAL lymphocytosis was defined as a lymphocyte differential count > 15%, and the cut-off was corroborated by survival classification and regression tree analysis. Results Overall, 186 patients (37 iNSIP, 16 iPPFE, and 133 unclassifiable IIP) were analyzed. Limited to patients treated with anti-inflammatory drugs (n = 123), patients with BAL lymphocytosis had a better prognosis [hazard ratio (HR), 0.26; 95% confidence interval (CI), 0.11–0.63; P = 0.003], higher slope of forced vital capacity (FVC) % predicted for 2 years, and longer OS (log-rank test, P = 0.012) than those without BAL lymphocytosis. On multivariate analysis, BAL lymphocytosis (HR 0.31; 95% CI 0.13–0.75; P = 0.009) was a prognostic factor for OS, along with age and FVC % predicted. Conversely, for patients managed without anti-inflammatory therapy (n = 63), the presence or absence of BAL lymphocytosis had no prognostic value. Conclusions BAL lymphocytosis is associated with good outcomes in patients treated with anti-inflammatory drugs, but has no prognostic value when anti-inflammatory drugs are not used. BAL lymphocytosis may provide a predictive biomarker for identifying patients with iNSIP, iPPFE and unclassifiable IIP who are likely to benefit from anti-inflammatory drugs.

Interstitial Score and Concentrations of IL-4Rα, PAR-2, and MMP-7 in Bronchoalveolar Lavage Fluid Could Be Useful Markers for Distinguishing Idiopathic Interstitial Pneumonias

Idiopathic interstitial pneumonia (IIP) entails a variable group of lung diseases of unknown etiology. Idiopathic pulmonary fibrosis, nonspecific interstitial pneumonia, interstitial lung diseases related to connective tissue disease (CTD-ILD), and hypersensitivity pneumonitis (HP) can manifest with similar clinical, radiological, and histopathological features. In a differential diagnosis, biomarkers can play a significant role. We assume that levels of specific cyto- or chemokines or their receptors can signal pathogenetic processes in the lungs. Eighty patients with different types of idiopathic interstitial pneumonia were enrolled in this study. Cell counts and concentrations of tumor necrosis factor (TNF)-α, interleukin-4 receptor α, proteinase-activated receptor (PAR)-2, matrix metalloproteinase (MMP)-7, and B cell-activating factor were measured in bronchoalveolar lavage fluid using commercial ELISA kits. High resolution computer tomography results were evaluated using alveolar and interstitial (IS) score scales. Levels of TNF-α were significantly higher in HP compared to fibrosing IIP (p < 0.0001) and CTD-ILD (p = 0.0381). Concentrations of IL-4Rα, PAR-2, and MMP-7 were positively correlated with IS (p = 0.0009; p = 0.0256; p = 0.0015, respectively). Since TNF-α plays a major role in inflammation, our results suggest that HP is predominantly an inflammatory disease. From the positive correlation with IS we believe that IL-4Rα, PAR-2, and MMP-7 could serve as fibroproliferative biomarkers in differential diagnosis of IIP.