Impact of mediastinal lymph node enlargement on the prognosis of idiopathic pulmonary fibrosis

Abstract

BackgroundMediastinal lymph node enlargement (LNE) is common in idiopathic pulmonary fibrosis (IPF) and is known to be associated with the severity of lung fibrosis. However, the relationship between mediastinal LNE and the prognosis of IPF has not been determined to date.MethodsThis study included patients with IPF from the interstitial lung disease registry at Seoul National University Bundang Hospital, from January 2012 to March 2016. Two thoracic radiologists independently reviewed mediastinal LNE and lung parenchymal fibrosis and ground glass opacities in chest computed tomography scans of each patient, which were obtained upon diagnosis. Mortality and admission rates were analyzed.ResultsIn total, 132 patients (104 [78.8%] male; median age, 72 years; range, 51–84 years) were enrolled and 73 (55.3%) patients had mediastinal LNE (short axis ≥ 10 mm in diameter). Mortality was significantly higher among patients with LNE than among those without LNE (hazard ratio 2.26 [95% confidence interval 1.20–4.23], p = 0.011). Of the patients with LNE, 24.7% experienced acute exacerbation and 43.8% experienced hospital admission for respiratory causes, in comparison with 16.9% and 40.0% of patients without LNE respectively. Although patients with LNE had a tendency to have increased rate of acute exacerbation, it was not statistically significant.ConclusionMediastinal LNE in IPF is associated with increased mortality and its occurrence may be considered a poor prognostic factor in patients with IPF.

Mediastinal lymph node enlargement in idiopathic pulmonary fibrosis: relationships with disease progression and pulmonary function trends

“…In our cohort, a "diffuse" lymph node involvement -as de ned by 3 or more enlarged mediastinal lymph nodes -was strongly associated with lower survival rates, in line with previous ndings. Sin and coworkers [22] demonstrated the impact of mediastinal LNE on survival in an equally-sized IPF cohort with comparable size and similar proportion of patients showing lymph node enlargement on CT. Notably though, the large majority of patients in our study received anti brotic treatment after diagnosis, suggesting that the presence of multiple mediastinal lymphadenopathies may predict poorer prognosis despite treatment.…”

“…Assuming a survival rate of 70% in the group without mediastinal LNE over a follow up period of 2 years, a sample of 148 patients was calculated as required to provide the study with 90% power to detect a 2.26-fold increased mortality risk in the group with mediastinal LNE with a two-sided signi cance level of 5%. The effect size was chosen based on a previous study investigating the impact of mediastinal LNE on survival in IPF [22].…”

“…Mediastinal lymph node measurements were provided using electronic calipers. Lymph nodes with a short-axis diameter ≥ 10 mm were reported as enlarged, as previously described in papers focused on ILD [22,23].…”

“…The frequency of this nding has been reported in up to 70% of patients with a usual interstitial pneumonia pattern [18] [19], and in up to 58% of IPF patients [20] [21]. Although the biology underpinning mediastinal lymph node enlargement in these patients has never been clari ed, the presence of LNE on chest CT scans has been associated with increased all-cause mortality in IPF and other ILD [22,23], suggesting a role as useful prognostic factor in brotic lung disease. An ongoing randomized clinical trial currently exploring the e cacy of a human monoclonal antibody directed against the BAFF receptor on B cells in IPF patients (clinicaltrials.gov identi er NCT03287414) recognizes the presence of hilar/mediastinal lymphadenopathies on HRCT as one of the key inclusion criteria, based on the hypothesis that lymph node involvement may identify IPF patients with pronounced immune activation and who are therefore more likely to respond to the investigational treatment.…”

Spectrum of HRCT findings in interstitial lung diseases and their correlation with mediastinal lymphadenopathy

“…Sin S et al, hypothesized that lymphadenopathy in IPF could be related to disease severity and could be a predicting factor in disease prognosis. 12 Attili AK et al, concluded that intrathoracic lymphadenopathy is common in UIP and NSIP with an increase in lymphadenopathy over time which is associated with the progression of fibrosis. 13 Recent studies have attempted to establish a correlation between disease severity and the enlarged lymph node diameter.…”