Imaging diagnosis of combined pulmonary fibrosis and emphysema

Combined pulmonary fibrosis and emphysema (CPFE) was advocated by Cottin V et al. in 2005. They defined CPFE by clinical and radiological features ; pulmonary emphysema in the upper lung and various patterns of interstitial fibrosis, and most frequently the UIP pattern. CPFE shows characteristic pulmonary function tests (normal FEV₁% and decreased DL_CO despite severe emphysema) and imaging features. We will describe the imaging and pathologic features of CPFE. Imaging characteristics of CPFE include emphysema in the upper lung and pulmonary fibrosis in the lower lungs. The most striking imaging feature is multiple large thick walled cysts ; sometimes in subpleural regions in the upper lungs and within foci of fibrosis in the lower lungs. Lung cancer is frequently seen in CPFE patients. Pathologically, the UIP pattern is the most frequent pattern ; however, bronchocentric fibrosis is also frequently seen suggesting a deep relationship with smoking. We will discuss feature issues in the progressive clinical investigation concerning CPFE.