Risk of Acute Exacerbation of Interstitial Pneumonia After Pulmonary Resection for Lung Cancer in Patients with Idiopathic Pulmonary Fibrosis Based on Preoperative High-Resolution Computed Tomography

Purpose. In patients with lung cancer accompanied by idiopathic pulmonary fibrosis (IPF), acute exacerbation of the IPF often occurs after pulmonary resection; however, few studies have been done to identify its preexisting risk factors. Methods. We analyzed the high-resolution computed tomography (HRCT) findings of IPF to identify the radiological characteristics of IPF susceptible to acute exacerbation after lung cancer surgery. We reviewed retrospectively 28 lung cancer patients with IPF who underwent pulmonary resection. Clinical data, respiratory function, HRCT findings, and historical features were compared between the acute exacerbation (n = 9) and nonexacerbation (n = 19) groups. The classification of radiological findings of IPF on HRCT was done using a scoring system of seven factors related to the interstitial shadow, including fibrosis, ground-glass opacity, and low-attenuation area. Results. There were no significant differences in clinical background, respiratory function, composite physiologic index, or pathological features between the groups; however, the degree of fibrosis on preoperative HRCT was significantly higher in the exacerbation group (P < 0.003). The fibrosis score was higher on the opposite side to the lung cancer in the exacerbation group (P < 0.05). Conclusion. Although it is difficult to predict postoperative acute IPF exacerbation, the degree and laterality of co-existing fibrosis seem to be predictors.