Background: To investigate whether the better prognosis of interstitial pneumonias associated with collagen vascular disease (CVD) compared with idiopathic interstitial pneumonia (IIP) is due to higher frequency of the nonspecific interstitial pneumonia (NSIP) pattern in CVD, we compared the outcomes of patients from these two groups with the same histopathologic pattern. Subjects: The clinical features and survival of 362 patients (269 with IIP and 93 with CVD) diagnosed using surgical lung biopsy were analyzed. Results: The mean survival of the CVD group (131.0 mo) was longer than that of the IIP group (80.5 mo) (p < 0.0001). The patients with usual interstitial pneumonia pattern among the CVD group (n = 36) was younger, female, and predominantly nonsmoking compared with the IIP group (n = 203). Although baseline lung functions were not significantly different, the CVD group survived longer (mean, 177.0 mo) than the IIP group (mean, 66.9 ± 6.5 mo; p = 0.001). By multivariate analysis, younger age, better pulmonary function, and the presence of a CVD were independent prognostic factors. In NSIP pattern, no significant differences in survival, clinical features, or lung function were found between the two groups. Conclusion: Our data suggest that the better prognosis of patients in the CVD group is not solely due to the predominance of the NSIP pattern. The prognosis of patients with the usual interstitial pneumonia pattern in CVD is better than in those with idiopathic pulmonary fibrosis, despite the same pathologic pattern. In contrast, in those with an NSIP pattern, the prognosis is similar in both groups.

Although acute exacerbations of idiopathic pulmonary fibrosis are well recognised, there are no studies documenting their prevalence or identifying pre-existing risk factors.This study analysed the clinical, radiological and pathological data of 11 patients who satisfied the criteria for acute exacerbation among 147 patients with biopsy-proven idiopathic pulmonary fibrosis. There were five additional patients who had similar demographics, radiology and surgical lung biopsy pathology, but had clinically less severe disease, and so were not included. The 2-yr frequency of acute exacerbation was 9.6% after the diagnosis. Most exacerbations were idiopathic, although two cases presented after surgical lung biopsy and one after bronchoalveolar lavage.No significant risk factor was found by univariate proportional hazard analysis. Imaging revealed diffuse bilateral ground-glass opacification superimposed on subpleural reticular and honeycombing densities. The biopsies of four patients taken during acute exacerbation exhibited diffuse alveolar damage superimposed upon usual interstitial pneumonia.The findings of this study demonstrate that acute exacerbation of idiopathic pulmonary fibrosis is rather common and this exacerbation is likely to have a spectrum of severity.

Idiopathic pulmonary fibrosis (IPF) was reported to be associated with increased risk of lung cancer as a result of the occurrence of atypical or dysplastic epithelial changes in fibrosis which progressed to invasive malignancy. In that situation, the cancer will develop in the area of major fibrosis. To investigate the direct relationship between fibrosis and cancer development, the real concordance rate of the two lesions in the chest computed tomography (CT) was analysed and compared to the histological types of lung cancer.The subjects included 63 patients with combined lung cancer and IPF (IPF-CA), 218 patients with lone IPF, and 2,660 patients with primary lung cancer. All patients were diagnosed at Asan Medical Center during the same period.The age, percentage of smokers, and the male sex were significantly higher in IPF-CA compared with lone IPF. The odds ratio of smoking was 2.71 compared to nonsmoking IPF controls. In IPF-CA, 56% of the cancer was located in the periphery of the lung and 52% in the upper lobe. The majority of the cancers (64%) were found in the nonfibrotic area at chest CT. The most frequent cell type was squamous cell carcinoma (35%), and there was no significant difference in the cancer cell type between IPF-CA and total lung cancer population.These findings suggest that in combined lung cancer and idiopathic pulmonary fibrosis patients, the features of the lung cancer are similar to the total lung cancer population.

The overall safety of surgical lung biopsy in patients with idiopathic interstitial pneumonia (IIP) remains controversial. This study was performed to investigate the mortality and complication rate and identify the risk factors for surgical lung biopsy in patients with IIP. A total of 200 patients with IIP who underwent surgical lung biopsy at the Asan Medical Center, Korea, from April 1990 to August 2003, were enrolled. Complications and mortality were analyzed retrospectively. (1) The mortality rate 30 days after the surgical lung biopsy was 4.3%, which was significantly higher than the control group. Biopsy performed at the time of acute exacerbation (AE) resulted in higher 30-day mortality (28.6%) compared to non-AE (3.0%; p<0.05). AE was followed by biopsy itself in three cases. (2) Univariate analysis indicated that lower FVC, lower DL(CO), and presence of AE were significant risk factors for 30-day mortality (p<0.05). However, multivariate analysis revealed that only AE (OR: 11.334, 95% CI: 1.727-74.365, p=0.011) was an independent risk factor. (3) The patients with low DL(CO) (<50% predicted) had higher mortality and complication rate than high DL(CO) group. Our data suggested that the presence of acute exacerbation at the time of biopsy and lower DL(CO) were predictors of higher mortality after the surgical lung biopsy.

Shin TR, et al. J Korean Med Sci. 2015 Oct;30(10):1459-1465. https://doi.org/10.3346/jkms.2015.30.10.1459