Combined pulmonary fibrosis and emphysema syndrome: clinical research progress

Combined pulmonary fibrosis and emphysema (CPFE) is a distinct radiological–clinical syndrome defined by the coexistence of upper-lobe emphysema and lower-lobe fibrosis. It predominantly affects elderly heavy smokers and exhibits a hallmark physiological paradox: preserved lung volumes with severely impaired gas exchange and exertional hypoxaemia. This review synthesises current evidence on CPFE pathogenesis, diagnosis, and management, focusing on challenges arising from its unique pathophysiology. We critically examine the diagnostic implications of the pulmonary function “dissociation phenomenon” and the limitations of quantitative imaging. Persistent ambiguity in diagnostic criteria, variable geographic recognition, and the practical applicability of current definitions are also addressed. Management remains largely extrapolated from idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD). High-quality, CPFE-specific evidence is lacking, and no dedicated therapeutic framework exists. This review identifies key research gaps and underscores the urgent need for prospective studies to establish robust diagnostic and treatment strategies for this complex syndrome.