Identification of Early Pathologic Markers of Interstitial Lung Diseases
LM Sholl, IE Fernandez, IO Rosas, RF Padera. Brigham and Women's Hospital, Boston, MA
Background: The absence of longitudinal pathologic data in patients with developing interstitial lung disease (ILD) limits our understanding of the pathogenesis of these diseases. We retrospectively examined surgically resected “uninvolved lung” taken from patients with stage I non small cell lung carcinoma (NSCLC) in an attempt to discover early features of ILD, particularly usual interstitial pneumonitis, in this susceptible population. We correlated the pathologic findings at the time of surgical resection with the subsequent clinical and radiologic outcomes.
Design: Microscopic slides of uninvolved lung for 66 sequential patients who underwent surgery for stage I NSCLC in 2000 were evaluated by two pulmonary pathologists. None of the patients had clinical or radiologic evidence of ILD at the time of surgical treatment. Follow-up chest radiology and clinical features were extracted from the medical record.
Results: Mean patient age at time of surgery was 70, with 38 (58%) women and 54 (82%) smokers. Mean follow-up was 5 years and median survival was 7.8 years. 57 (86%) had at least mild emphysema, 22 (33%) had respiratory bronchiolitis, 19 (29%) had at least focal interstitial fibrosis, and 20 (30%) had at least moderate vascular disease. Two patients (3%) were subsequently radiologically diagnosed with ILD during follow-up; neither patient had received adjuvant therapy. One patient who developed bilateral lower-lobe predominant honeycomb change after 3 years had patchy subpleural interstitial fibrosis with small scattered fibroblast foci and minimal architectural distortion on the original biopsy. The other patient who developed bilateral subpleural reticular opacification and honeycombing after 8 years showed NSIP/DIP-like changes on the original biopsy.
Conclusions: Retrospective pathologic review of surgical lung cancer resections is a feasible approach to identifying the early lesions of ILD before they become clinically or radiologically manifest. Further study of these early lesions by molecular genetic techniques may provide insight into the early stages of development of these diseases. In our initial study, smoking-related changes were common findings in the lungs of patients with early stage NSCLC. These findings warrant a larger study to identify specific histologic features that predict which patients may go on to develop bona fide ILD.
Tuesday, March 23, 2010 1:00 PM
Poster Session IV # 255, Tuesday Afternoon