Idiopathic pulmonary fibrosis as a prognostic factor in non-small cell lung cancer

We investigated the postoperative mortality and long-term survival of lung cancer patients with underlying idiopathic pulmonary fibrosis (IPF). The data of 387 primary lung cancer patients treated by surgical resection at our hospital between 1995 and 2008 were retrospectively reviewed. Clinicopathological characteristics such as age, gender, survival, presence/absence of underlying IPF, atypical adenomatous hyperplasia (AAH), and the associations among these factors were examined. Among the 387 patients, 65 (16.8 %) had underlying IPF as detected by histopathology of the resected specimen (IPF group). The percentages of men and squamous cell carcinomas were significantly higher in the IPF group. None of our patients showed concomitant presence of AAH and IPF. Four of the 65 patients showed acute exacerbation of the IPF postoperatively, and all 4 of these patients died in hospital. In patients with non-small cell lung carcinoma, the postoperative survival tended to be lower in the IPF group than in the non-IPF group. Analysis using a Cox proportional hazards model by disease stage revealed that presence of underlying IPF was a risk factor for postoperative mortality in patients with pathological stage I/II but not for stage III/IV. Respiratory failure was the second main cause of death in the stage I/II lung cancer patients of the IPF group. Histopathological evidence of IPF was a risk factor for postoperative mortality and poor long-term survival, especially in patients with stage I/II non-small cell lung cancer, with postoperative respiratory failure representing the major cause of death.