Modified GAP index for prediction of acute exacerbation of idiopathic pulmonary fibrosis in non-small cell lung cancer

Background and objective: Predicting the incidence rate of acute exacerbation (AE) of idiopathic pulmonary fibrosis (IPF) and its prognosis in patients with non-small cell lung cancer (NSCLC) and IPF is difficult. The aim was to study the incidence of IPF-AE during the clinical course of the disease and its prognosis in patients with both NSCLC and IPF. Methods: In this retrospective study, we compared the incidence rate of AE during the clinical course of the disease as well as the 1-year survival rate and overall survival (OS) of patients with NSCLC and IPF using a modified gender, age and physiology (mGAP) staging system based on gender, age and percent predicted forced vital capacity. Results: Of 43 patients with NSCLC and IPF included in the final analysis, 17 patients (40%; 95% CI: 26-54%) experienced AE during the clinical course of the disease. One-year survival and median OS were 41.9% (95% CI: 28-57%) and 9.4 months, respectively. Further analysis showed that the incidence of IPF-AE gradually increased and that the 1-year survival rate and median OS gradually decreased with increasing mGAP index score and stage. Conclusion: Our study suggested that mGAP index score and cancer stage may predict IPF-AE and its prognosis in patients with NSCLC and IPF.