Abstract
Interstitial fibrosis with emphysema [also called smoking-related interstitial fibrosis (SRIF), or airspace enlargement with fibrosis] is increasingly recognised, described with co-existing lung cancer.
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We undertook a prospective clinical, radiological and pathological analysis of non-cancerous lung from lung cancer resections (n=20), assessing smoking history, fibrosis and small airway changes by histology (see Katzeinstein AL et al 2010) and by protocol-derived high resolution CT (HRCT).
Histological emphysema-associated interstitial fibrosis (SRIF) was found in 40%, distant to the lung cancer and associated with small airway changes.
Gender and age distribution was similar in both SRIF and non-SRIF subjects, with SRIF observed in 87.5% in the right lung, (62.5% in the right upper lobe), and associated with decreased forced expiratory volume in 1 second (p=0.0026). In all, SRIF had no HRCT correlate.
We assessed the histological findings in explanted lungs from radiologic emphysema subjects [n=20 chronic obstructive pulmonary disease (COPD), mean cigarette pack-years (PY)=45; n=20 alpha 1-antitrypsin deficiency (A1AT), mean PY=25]; SRIF was observed in 40% of COPD and 25% of A1AT (linear correlation with mean PY).
In summary, histologic fibrosis with emphysema is radiologically occult, highly prevalent, with a dose-response relationship to smoking, and independent of the cancer in the nearby lung.
- © 2014 ERS
